Tonight I measured and cut my 1 1/4 inch x 1/8 inch thick steel angle in 4 pieces, each 13 inches long. I used the recprocating saw with the metal cutting blade - the same one I used to bevel the corners of the wing stands. This was like cutting through butter compared to the 1/4 inch thick wing stands, so it went fairly quickly.
The widest part of the wing spars is about 7.75 inches wide, so a one foot long piece of angle would allow the spar to just fit nicely on the entire support. Since 4 inches are aligned with the inside edge of the wing stand, that leaves 9 inches for the spars to rest on, which should be plenty. I opted to cut them a little longer than necessary, mostly to allow for the 1/4 to 1/2 inch adjustment that may be needed to level each angle after attaching them to my wing stands.
I also measured and marked the 4 support angles for the first of two holes that need to be drilled in each support bracket - one for the attachment bolt to the post, and the other to accept the bracket that will hold the 5/16 inch threaded rod. I expect to be drilling most of the remaining holes tomorrow after work.
No pics tonight, but I did manage to visit Aaron Miller's build log to check up on his progress since we got the wing stands welded together. This post shows some pics he took of me "in action" with a welder in my hand. Dangerous stuff for sure! Looks like he is up and running with both his wings. I envy the room he has in his basement. Before long he will be wheeling his entire airplane out of the basement and onto his taxi way where he will taxi all the way to the runway for his first flight.
ON another note - Looks like Van's has officially indicated on their facebook page that they have reached a new milestone of 8000 flying RVs! What an amazing accomplishment, considering that they were already the most popular flying kit airplane manufacturer when they only had 6500 of them flying not so long ago. Guess I better get busy and finish this thing!
And finally, looks like friend and fellow builder Ron Duren made the big move to KBJC last weekend. Congrats to him - he really put in a lot of work to get things to this point, and I think he is well on his way to a probable first flight some time this coming spring.
Tuesday, February 5, 2013
Monday, February 4, 2013
....And for tonight's math lesson........
....We will perform a variety of calculations to arrive at the measurement for the the desired height for the shelving brackets that will support the wing spars. There are a couple of things to consider here:
1. What is the comfortable standing height that I can easily rivet the skins to the spar and ribs?
2. Do I need to leave enough room at the bottom of the stand to position the control surfaces (ailerons and flaps) from the trailing edge, and if so, how much room do I need to leave?
A couple of general measurements were taken of the main ribs, the leading edge ribs, the wing spar flanges, and the overall width of the entire wing assembly.
Overall width of the wing according to the wing tip: Approx 60 inches, or 5 feet
Main rib: 26.5 inches
Leading edge rib: 17.5 inches
Total of main and leading edge ribs: Approx 44 inches, plus about 1/16th inch for the thickness of the spar and another 1/16th for the trailing edge spar.
60-44 leaves 16 inches. This is the amount of space I would need to leave on the bottom if I wanted to be able to attach the finished control surfaces to the TE of the wing while they are still in the stands. I think most folks are attaching these when the wing is removed from the stands and placed inthe wing cradle so that the TE is now facing up, making the hinge attach points a bit easier to manage. So I don't think that leaving enough space for the control surfaces on the bottom is a major consideration.
Another aspect of this to consider is that if I do decide to leave enough room on the bottom, a jack will have to reach up that far to support the middle of the wing that naturally starts to sag in the middle when everything is attached to the wing spar until the wing skins are riveted into place. The higher the gap the longer the jack needs to reach to support the rear spar.
When I stood in front of the wing stands, I found that my arm comfortably supports the rivet gun and drill at about 48-50 inches from the floor. Aaron told me that he positioned his support brackets at about 55 inches, but he is also notably taller than I am, so I would naturally expect that from a standing position my brackets would probably be a bit lower than his.
Here is a pic, courtesy of Sean Thomas' RV-7 project, that shows the relative height of his wing stands:
Although I did not measure the height of his support brackets, they also appear to be more along the 48 inch high range. One other consideration for this is a comfortable sitting height when the time comes to rivet the skins on one side of the wing. You want to be able to sit in a chair and comfortably reach from the highest to lowest rivets along each rib while you rivet the skins together.
A few more calculations:
16 + 26.5 (gap for control surfaces plus main rib length) = 42.5.
The leading edge skins will be attached to the nose ribs using the LE cradle, so I won't need to worry so much about a height that makes it easy to rivet the nose ribs in place, only for the attachment of the LE skins to the main wing spar.
So for now, I think I will settle for a placement of the support brackets somewhere between 48 to 50 inches, or perhaps a bit lower. I will sleep on it and decide tomorrow, and then mark and drill some more holes for the support bracket hardware.
1. What is the comfortable standing height that I can easily rivet the skins to the spar and ribs?
2. Do I need to leave enough room at the bottom of the stand to position the control surfaces (ailerons and flaps) from the trailing edge, and if so, how much room do I need to leave?
A couple of general measurements were taken of the main ribs, the leading edge ribs, the wing spar flanges, and the overall width of the entire wing assembly.
Overall width of the wing according to the wing tip: Approx 60 inches, or 5 feet
Main rib: 26.5 inches
Leading edge rib: 17.5 inches
Total of main and leading edge ribs: Approx 44 inches, plus about 1/16th inch for the thickness of the spar and another 1/16th for the trailing edge spar.
60-44 leaves 16 inches. This is the amount of space I would need to leave on the bottom if I wanted to be able to attach the finished control surfaces to the TE of the wing while they are still in the stands. I think most folks are attaching these when the wing is removed from the stands and placed inthe wing cradle so that the TE is now facing up, making the hinge attach points a bit easier to manage. So I don't think that leaving enough space for the control surfaces on the bottom is a major consideration.
Another aspect of this to consider is that if I do decide to leave enough room on the bottom, a jack will have to reach up that far to support the middle of the wing that naturally starts to sag in the middle when everything is attached to the wing spar until the wing skins are riveted into place. The higher the gap the longer the jack needs to reach to support the rear spar.
When I stood in front of the wing stands, I found that my arm comfortably supports the rivet gun and drill at about 48-50 inches from the floor. Aaron told me that he positioned his support brackets at about 55 inches, but he is also notably taller than I am, so I would naturally expect that from a standing position my brackets would probably be a bit lower than his.
Here is a pic, courtesy of Sean Thomas' RV-7 project, that shows the relative height of his wing stands:
Although I did not measure the height of his support brackets, they also appear to be more along the 48 inch high range. One other consideration for this is a comfortable sitting height when the time comes to rivet the skins on one side of the wing. You want to be able to sit in a chair and comfortably reach from the highest to lowest rivets along each rib while you rivet the skins together.
A few more calculations:
16 + 26.5 (gap for control surfaces plus main rib length) = 42.5.
The leading edge skins will be attached to the nose ribs using the LE cradle, so I won't need to worry so much about a height that makes it easy to rivet the nose ribs in place, only for the attachment of the LE skins to the main wing spar.
So for now, I think I will settle for a placement of the support brackets somewhere between 48 to 50 inches, or perhaps a bit lower. I will sleep on it and decide tomorrow, and then mark and drill some more holes for the support bracket hardware.
Sunday, February 3, 2013
Mounted Wing Stands to the concrete floor
Well the day finally came to drill some holes in the concrete and bolt the wing stand down. What better day then Super Bowl Sunday to work out in the shop, especially with the weather at a balmy 60 degrees. What you won't see in the pics is the large amount of time spent yesterday forming a large number of flat metal shims out of 1/8 inch thick strips of steel. This proved to be avery challenging exercise, and as I have mentioned in previous posts I pretty much figured that it would be, since my concrete floor in the garage is less than acceptable for doing anything that requires a "flat" surface.
I literally had to trial fit each stand, measure the distance between them, and check the wobble of each one and then figure out the best method of shimming each one up to remove the wobble. That process really sucked, but I managed to get it done. The only thing I was concerned about was ensuring that the 114 inches of space between the inside edges of both stands for each wing was retained. I quickly found that without the shims in place that each stand was leaning inward bit, so I was losing my 114 inch distance the higher up the stand that I measured. Anyway, I cut out several pieces of metal for 3 out of the 4 stands. One of them did not need much shimming at all, so that was good. Only problem was that it still required shimming on one side only, but the 1/8 inch shims were too thick for what I needed. I ended up using a piece of .032 aluminum from my trim bundle that I had used as a test piece for the 2 part epoxy primer I started using on the wings a long time ago. This seemed to do the trick.
Anyway, it all started with determining general placement of the stands. This involved clearing the refrigerator and freezer door travel, and, most importantly, allowing enough room for getting both cars in the garage with both wings on both stands. After this general placement was figured out, I snapped some straight lines with a chalk line, as shown below:
The stands in front of my work benches were the most challenging, because there is a separation or relief line where additional sections of garage floor were added by the previous owners of this house when they decided to make the garage larger than originally designed. I am glad that they decided to make the garage a bit larger, but I just wish that they would have re-poured the entire floor after they did it. As it is, the position of the wing stands straddles both sides of this stress relief line, so I am mounting one of the stands on two separate pieces of concrete. What a pain, not to mention a shimming nightmare.
Here is shot of the line I am talking about. The stands pretty much needed to go in this position because I needed enough room in front of the work bench to allow for working on ailerons and flaps and other work, and at the same time I had to position them so I could still get the cars in the garage. So that is why they ended up where they did. The best position for allowing other work on the benches and gettting the cars int he garage turns out to be about the worst position one might choose to mount something like this. Oh, well, par for the course for me I guess. Nothing is easy.
After the positioning and the chalk line, I used a sharpee with a thick tip to draw the outline or at least the critical lines for marking the position of each stand so that it would meet the 114 inch spacing per the plans.
Here are some tools of the trade used for the above tasks. I used the square to draw the sharpee lines so that they were exactly perpendicular to the snap line.
And here is the line for the stands along the right side of the garage. Yes, with this setup, I can still get both cars in the garage.
And here is just one example of the wacked out shimming job I had to perform. Note that the only thing I was concerned about was stability of the stands after being bolted to the floor so that they would maintain the 114 inch distance between the posts. I was much less concerned about the "level" attitude of the stands along the other plane, since the shelf assembly will be adjustable for level, so I can offset any leaning of the posts by adjusting the screw bolt so that the shelf will be level. At its worst the posts are about 1/4 inch to 3/8 inch off level, and I think the threaded rod will take care of that with no problem. Had I decided I wanted the posts perfectly level in all planes of existance I would certainly not be here writing about the experience now, because I would still be out in the garage trying to get everything perfectly level. Sometimes you just have to settle for less.
The above pic shows the anchors installed and the nuts torqued down to spec. The process I used to drill the holes was to use a rotary hammer drill with a six inch long 3/8 inch cobalt bit that I rented from HD. I drilled the holes with the stands in place, thanks to my trusty son Adam who held them in place while I drilled the holes. This was largely a non event, and I was quite surprised at how easily the drill cut through the concrete. Only problem is that for some reason one out of the 16 holes I had to drill either did not get cleaned out properly, or the concrete failed underneath, or the bolt anchor got messed up, or something, but it would not seat in the hole and would not grab the concrete. SO as a result I have one anchor that is unable to secure anything on one of the stands, so I will ahve to rely on the three good bolt anchors to keep that stand in place.
After all the bolts were torqued down, I check each stand for security, and I am not concerned at all about any of them ever moving so much as a muscle. They are all solidly mounted to the floor. Now I just have to drill the holes for the shelf hardware, threaded rods, and bottom trailing edge supports, adn cut the 1 1/4 inch angles to size and drill some more holes in those. As the saying goes, 90% done and 90% left to go.....
Here is the drill I used and the air tool I used to clean out each hole after it was drilled.
Many thanks to son Adam for his assistance today. While I am discouraged by the amount of time and effort I have had to expend on just meer fixtures, I am pleased that things finally look like they will be in place to allow me to meet or exceed my goal of getting both the wings about 95% done by the time Oshkosh 2013 rolls around.
I literally had to trial fit each stand, measure the distance between them, and check the wobble of each one and then figure out the best method of shimming each one up to remove the wobble. That process really sucked, but I managed to get it done. The only thing I was concerned about was ensuring that the 114 inches of space between the inside edges of both stands for each wing was retained. I quickly found that without the shims in place that each stand was leaning inward bit, so I was losing my 114 inch distance the higher up the stand that I measured. Anyway, I cut out several pieces of metal for 3 out of the 4 stands. One of them did not need much shimming at all, so that was good. Only problem was that it still required shimming on one side only, but the 1/8 inch shims were too thick for what I needed. I ended up using a piece of .032 aluminum from my trim bundle that I had used as a test piece for the 2 part epoxy primer I started using on the wings a long time ago. This seemed to do the trick.
Anyway, it all started with determining general placement of the stands. This involved clearing the refrigerator and freezer door travel, and, most importantly, allowing enough room for getting both cars in the garage with both wings on both stands. After this general placement was figured out, I snapped some straight lines with a chalk line, as shown below:
The stands in front of my work benches were the most challenging, because there is a separation or relief line where additional sections of garage floor were added by the previous owners of this house when they decided to make the garage larger than originally designed. I am glad that they decided to make the garage a bit larger, but I just wish that they would have re-poured the entire floor after they did it. As it is, the position of the wing stands straddles both sides of this stress relief line, so I am mounting one of the stands on two separate pieces of concrete. What a pain, not to mention a shimming nightmare.
Here is shot of the line I am talking about. The stands pretty much needed to go in this position because I needed enough room in front of the work bench to allow for working on ailerons and flaps and other work, and at the same time I had to position them so I could still get the cars in the garage. So that is why they ended up where they did. The best position for allowing other work on the benches and gettting the cars int he garage turns out to be about the worst position one might choose to mount something like this. Oh, well, par for the course for me I guess. Nothing is easy.
After the positioning and the chalk line, I used a sharpee with a thick tip to draw the outline or at least the critical lines for marking the position of each stand so that it would meet the 114 inch spacing per the plans.
Here are some tools of the trade used for the above tasks. I used the square to draw the sharpee lines so that they were exactly perpendicular to the snap line.
And here is the line for the stands along the right side of the garage. Yes, with this setup, I can still get both cars in the garage.
And here is just one example of the wacked out shimming job I had to perform. Note that the only thing I was concerned about was stability of the stands after being bolted to the floor so that they would maintain the 114 inch distance between the posts. I was much less concerned about the "level" attitude of the stands along the other plane, since the shelf assembly will be adjustable for level, so I can offset any leaning of the posts by adjusting the screw bolt so that the shelf will be level. At its worst the posts are about 1/4 inch to 3/8 inch off level, and I think the threaded rod will take care of that with no problem. Had I decided I wanted the posts perfectly level in all planes of existance I would certainly not be here writing about the experience now, because I would still be out in the garage trying to get everything perfectly level. Sometimes you just have to settle for less.
The above pic shows the anchors installed and the nuts torqued down to spec. The process I used to drill the holes was to use a rotary hammer drill with a six inch long 3/8 inch cobalt bit that I rented from HD. I drilled the holes with the stands in place, thanks to my trusty son Adam who held them in place while I drilled the holes. This was largely a non event, and I was quite surprised at how easily the drill cut through the concrete. Only problem is that for some reason one out of the 16 holes I had to drill either did not get cleaned out properly, or the concrete failed underneath, or the bolt anchor got messed up, or something, but it would not seat in the hole and would not grab the concrete. SO as a result I have one anchor that is unable to secure anything on one of the stands, so I will ahve to rely on the three good bolt anchors to keep that stand in place.
After all the bolts were torqued down, I check each stand for security, and I am not concerned at all about any of them ever moving so much as a muscle. They are all solidly mounted to the floor. Now I just have to drill the holes for the shelf hardware, threaded rods, and bottom trailing edge supports, adn cut the 1 1/4 inch angles to size and drill some more holes in those. As the saying goes, 90% done and 90% left to go.....
Here is the drill I used and the air tool I used to clean out each hole after it was drilled.
Many thanks to son Adam for his assistance today. While I am discouraged by the amount of time and effort I have had to expend on just meer fixtures, I am pleased that things finally look like they will be in place to allow me to meet or exceed my goal of getting both the wings about 95% done by the time Oshkosh 2013 rolls around.
Sunday, January 27, 2013
Primed and painted the Wing Stands
I managed to get the wing stands scuffed, re-cleaned, primed and painted. A long time ago, way back when I began this project, I had completed Van's Tool box kit after receiving my tools from Cleaveland Tools to acclamate myself to them in preparation for the larger task ahead. When the toolbox was completed I purcchased some spray paint to match the colors that had grabbed my attention at the time - a bright blue and an aircraft gray. I had planned to use them on the toolbox, but I never did. So it has remained primed with Napa 7220 gray primer ever since.
Fast forward to today. I knew that I needed to properly preserve the steel wing stands by priming them and painting them once they were ready, and that day finally came. I used a wire bristle brush in my electric drill to rough up the surfaces of all four stands, and then re-cleaned them with acetone. I also used a tapered grinding bit that fits in my drill to debur each of the mounting holes in the bases. I then primed all four stands them with about 1.5 cans of Napa 7220.
Then finally, holding true to my nature to act, think, speak, and do things differently than most others, I did not paint them all with just one solid pretty color. Instead, I remembered that I still had the blue and gray paint on the shelf, and decided to have some fun. I decided to emulate the top and botton color scheme as seen on the photo at the top of my blog. I used the aircraft gray paint on the bottom of each stand, and the blue paint on the top. I also chose not to make any clean, crip lines that separate the two colors. Since one of my absolute passions in life is WW II aircraft, I wanted to try my hand at using paint from spray can to create the airbrushed non-linear blended look of the two colors, similar to the way that WWII aircraft were painted as part of their camoflage schemes. Here are some shots of the results:
I have to say I like the results. Others will probably look at this and have other opinions, and I really don't care. Just one of the pleasures of living in a free country where I can choose to use whatever colors I want to build my own airplane! An interesting thing about this ceramic blue hight temp engine block paint that used. It seems to have a multi-color characteristic to it. It turns a light turqois in the sunlight, and is a much darker blue tone in the shade. Here is another shot of all of them side by side. Just imagine this is the paint line of my fuselage :)
With the help of my son I also repositioned the hanging bracket for my HS so that it would be a little bit easier than where I had it before, but the refrigerator has proved to make it just as difficult to hang, so no matter what I try this task is still a bit difficult, but do-able.
Now my work table is free again, and I can start match drilling ribs to the wing spars by clamping one spar to the table and the other one to the work benches. Next steps are also to mark the final locations for both sets of wing stands, rent the rotary hammer drill, drill the 16 mounting holes in the concrete floor, and then finish installing the remaining hardware for the angle cross members that will actually support each wing spar at a good working height. I am still concerned about the un-evenness of my concrete floor, but since the angle supports will be adjustable for level, regardless of the less level attitude of the wing stands due to the unneven floor, I am not terribly concerned about it. as long as the centerlines of each stand are relatively close aligned with each other, I can adjust the angle supports for leveling the spars with no problem.
One thing that I still have to resolve is that I need to ensure that there is enough room in front of the work benches so that I can use them to build the flaps and ailerons that also come with the wing kit. The only problem is that my concrete floor has a relief line between two separate slabs of poured concrete, and in order to preserve the spacing in front of the work benches and still be able to get both cars in the garage I will need to position the wing stands in such a way that the mounting brackets will straddle both slabs of concrete. Since the slabs are at least 20 years old, I think this will be OK, but it might make lining up the stands on both ends a bit of challenge.
I will need to snap some chalk lines once I have made my final decisions as to the pacement of the stands, and then I get to try my hand at a rotary hammer drill for the first time. Lucky me!
Fast forward to today. I knew that I needed to properly preserve the steel wing stands by priming them and painting them once they were ready, and that day finally came. I used a wire bristle brush in my electric drill to rough up the surfaces of all four stands, and then re-cleaned them with acetone. I also used a tapered grinding bit that fits in my drill to debur each of the mounting holes in the bases. I then primed all four stands them with about 1.5 cans of Napa 7220.
Then finally, holding true to my nature to act, think, speak, and do things differently than most others, I did not paint them all with just one solid pretty color. Instead, I remembered that I still had the blue and gray paint on the shelf, and decided to have some fun. I decided to emulate the top and botton color scheme as seen on the photo at the top of my blog. I used the aircraft gray paint on the bottom of each stand, and the blue paint on the top. I also chose not to make any clean, crip lines that separate the two colors. Since one of my absolute passions in life is WW II aircraft, I wanted to try my hand at using paint from spray can to create the airbrushed non-linear blended look of the two colors, similar to the way that WWII aircraft were painted as part of their camoflage schemes. Here are some shots of the results:
I have to say I like the results. Others will probably look at this and have other opinions, and I really don't care. Just one of the pleasures of living in a free country where I can choose to use whatever colors I want to build my own airplane! An interesting thing about this ceramic blue hight temp engine block paint that used. It seems to have a multi-color characteristic to it. It turns a light turqois in the sunlight, and is a much darker blue tone in the shade. Here is another shot of all of them side by side. Just imagine this is the paint line of my fuselage :)
With the help of my son I also repositioned the hanging bracket for my HS so that it would be a little bit easier than where I had it before, but the refrigerator has proved to make it just as difficult to hang, so no matter what I try this task is still a bit difficult, but do-able.
Now my work table is free again, and I can start match drilling ribs to the wing spars by clamping one spar to the table and the other one to the work benches. Next steps are also to mark the final locations for both sets of wing stands, rent the rotary hammer drill, drill the 16 mounting holes in the concrete floor, and then finish installing the remaining hardware for the angle cross members that will actually support each wing spar at a good working height. I am still concerned about the un-evenness of my concrete floor, but since the angle supports will be adjustable for level, regardless of the less level attitude of the wing stands due to the unneven floor, I am not terribly concerned about it. as long as the centerlines of each stand are relatively close aligned with each other, I can adjust the angle supports for leveling the spars with no problem.
One thing that I still have to resolve is that I need to ensure that there is enough room in front of the work benches so that I can use them to build the flaps and ailerons that also come with the wing kit. The only problem is that my concrete floor has a relief line between two separate slabs of poured concrete, and in order to preserve the spacing in front of the work benches and still be able to get both cars in the garage I will need to position the wing stands in such a way that the mounting brackets will straddle both slabs of concrete. Since the slabs are at least 20 years old, I think this will be OK, but it might make lining up the stands on both ends a bit of challenge.
I will need to snap some chalk lines once I have made my final decisions as to the pacement of the stands, and then I get to try my hand at a rotary hammer drill for the first time. Lucky me!
Tuesday, January 22, 2013
Drilling holes in Wing Stand Supports
Last night I finally managed to finish drilling all the mounting holes in the base of the wing stands. It all starts with the measurements - 1/2 inch round bolt holes for each 3/8 inch wedge bolt and washer that will be placed in the concrete, spaced at approximately 14 inch centers, 2 inches in from the outer edge of each angle, with centers at 7/8 inches from the sides as shown by the sharpee marks:
Next comes a pilot hole using a 1/4 inch titanium coated drill bit with a pilot bit on the end for drilling in metal: (sorry for the blurry pic)
And next are the 1/4 inch pilot holes. I used some boe-lube to lubricate the bit ocassionally:
The process of drilling all these holes took me a while. It seemed that in some cases the bits would dull after the first use and would not cut as well for subsequent holes, and other times....well, lets just say I found a way to break "titanium" with relative ease a few times! Notice the slight bend in one of the bits in the following pic. This was a 7/32 bit - slightly smaller than the 1/4 inch bit, but apparently a whole lot less rigid. I found that there is a technique involved where as the drill but starts to get close to exiting out the other side, you need to ease off the pressure being applied on the bit. That seemed to help some.
It seems that when the bit starts to penetrate the far side of the metal, it tends to grab quite hard - probably due to my 3/8 inch electric drill not having enough RPM to do this correctly - and the keyless chuck that kept coming loose every so often did not help much either. Fortunately the 1/2 inch drill bit never faltered on me, so those holes all went fairly well:
And finally, I am going to use Red Head 2 1/4 inch x 3/8 inch concrete anchors to secure each wing stand to the concrete. My plan is to use a rotary hammer drill with a 3/8 inch carbide bit, place and draw the outline of the angles and the mounting holes with a sharpee, and got to town with the hammer drill. These anchors require a minimum depth of 1 1/2 inches, and the instructions say to drill another 1/4 inch deeper - so 1 3/4 inches deep is all that is needed. After you account for the 1/4 inch depth of the angle and the washer and nut, it leaves about 1/8 of an inch to torque down the nut to secure the stands to the anchors.
No, this is not going to be the final resting place of this wing stand, right over one of many cracks in my floor! I just took this to show the alignment of the holes in the flanges after they are drilled to size. I did trial fit one of the 3/8 inch anchors into the 1/2 inch hole, and I have to agree with Aaron that having a bit of wiggle room for the bolt is a good idea. The washer and nut feels like it will securely attach the stand to the floor, and I am not concerned about the over-sized mounting holes for the bolts I am using. These suckers are extremely heavy, so positioning and marking the locations for the stands on the floor will be a 2 person job. The last thing I want is for one of these things toppling over on me - that would be a very bad day in the airplane shop indeed.
One more step done......
Next comes a pilot hole using a 1/4 inch titanium coated drill bit with a pilot bit on the end for drilling in metal: (sorry for the blurry pic)
And next are the 1/4 inch pilot holes. I used some boe-lube to lubricate the bit ocassionally:
The process of drilling all these holes took me a while. It seemed that in some cases the bits would dull after the first use and would not cut as well for subsequent holes, and other times....well, lets just say I found a way to break "titanium" with relative ease a few times! Notice the slight bend in one of the bits in the following pic. This was a 7/32 bit - slightly smaller than the 1/4 inch bit, but apparently a whole lot less rigid. I found that there is a technique involved where as the drill but starts to get close to exiting out the other side, you need to ease off the pressure being applied on the bit. That seemed to help some.
It seems that when the bit starts to penetrate the far side of the metal, it tends to grab quite hard - probably due to my 3/8 inch electric drill not having enough RPM to do this correctly - and the keyless chuck that kept coming loose every so often did not help much either. Fortunately the 1/2 inch drill bit never faltered on me, so those holes all went fairly well:
And finally, I am going to use Red Head 2 1/4 inch x 3/8 inch concrete anchors to secure each wing stand to the concrete. My plan is to use a rotary hammer drill with a 3/8 inch carbide bit, place and draw the outline of the angles and the mounting holes with a sharpee, and got to town with the hammer drill. These anchors require a minimum depth of 1 1/2 inches, and the instructions say to drill another 1/4 inch deeper - so 1 3/4 inches deep is all that is needed. After you account for the 1/4 inch depth of the angle and the washer and nut, it leaves about 1/8 of an inch to torque down the nut to secure the stands to the anchors.
No, this is not going to be the final resting place of this wing stand, right over one of many cracks in my floor! I just took this to show the alignment of the holes in the flanges after they are drilled to size. I did trial fit one of the 3/8 inch anchors into the 1/2 inch hole, and I have to agree with Aaron that having a bit of wiggle room for the bolt is a good idea. The washer and nut feels like it will securely attach the stand to the floor, and I am not concerned about the over-sized mounting holes for the bolts I am using. These suckers are extremely heavy, so positioning and marking the locations for the stands on the floor will be a 2 person job. The last thing I want is for one of these things toppling over on me - that would be a very bad day in the airplane shop indeed.
One more step done......
Sunday, January 20, 2013
Wing Stands Work Cont'd
Over this weekend I finally got to do some more work on the wing stands. They are still not to the point where I am ready to clamp the wing spars on them, but as with so mnay other things about this project - you just have to keep doing all the little things that need to be done, and one day you will have a completed airplane. Just ask Ron Duren, who just announced after a long, extremely focused work ethic on his RV-7 project, recently announced that he is ready for the big move from the garage to the hangar at the airport. Usually once that is done it is not too much longer afterward that ingeine first starts and first flights are performed.
First pic is of the bottom of the wing stands. Note how the welds have been ground down so they are flush with the bottom of the flanges. Since one of the two welds performed on each angle bracket was on the bottom, these welds have to be ground down so that the stand will sit level on the concrete floor of the garage.
Aaron had already done a great job grinding down 3 of the four stands while they were still at his house before I loaded them up in the car for the ride home several weeks ago. The last one still needed to be done as shown in the pic below:
In addition to grinding down the bottom welds, Aaron had told me to cut wedges in the flanges of the angles to avoid catching your foot on them. Since his Dad's plasma cutter was not cooperating with the generator on the day they were welded to the posts, we resolved to use a reciprocating saw with a metal cutting blade to do the job. This, in addition to the grinder and an abrasive 3M wheel to clean the weld joint and remove corrosion, were the tools utilized this weekend as shown below:
The abrasive wheel is chucked in the drill. The metal blade in the recip saw really worked well to trim the flanges. It was a little bit of a trick to figure out how to hold the saw blade to trim only one flange at a time. Even more amazing was how this saw blade basically cuts through 1/4 inch thick steel with relative ease. I have used the recip saw for a variety of projects over the years, and I sort of have a love/hate relationship with the thing. In some instances it has almost broken my arm, and in other instances it works just fine with no problems whatsoever. Luckily the latter was the result on this particular project.
Here is a shot of the finished cuts from the saw. Basically I am just cutting a 45 degree angle or so on each vertical flange of each angle. Not shown yet is that I then took the grinder and removed all the sharp cut edges on each cut. The hope is that I will not catch my foot or cut myself on these while I work around the wing.
I then marked the positions for the mounting holes on the bottom of each flange, and per information from Aaron as to how he did this, I purchased a set of titanium bits with a pilot tip (DEwalt) that are 2 inches in from the edges of each angle, centered at 7/8 inches from the edge. Keep in mind that the angles are 2x2 inches wide, and 18 inches long. So you might think that the holes need to be centered at 1 inch centers. However, you alos ahve to keep in mind that they are 1/4 inch thick, and that 2x2 inch measurement is from the outside edge of each angle, so it does not account for the 1/4 inch thickness of each flange. So you need to measure the center point for the mounting bolt hole based on the inside distance of the angle, or 1 and 3/4 inches. This puts the centers at 7/8 inches from the outer edge. I then drilled a pilot hole with the 1/4 inch drill bit and was amazed again at how well the bit drilled through the still flange. I used some boe lube wax to help lubricate the bit. I then followed up with a 1/2 inch bit. Even though the anchor bolts I am using are only 3/8 inch bolts, Aaron suggested that I drill 1/2 inch wide bolt holes in the angles to allow some wiggle room in case the anchors are misaligned slightly from perfect 14 inch centers, which is highly likely.
I got the mounting holes drilled in 2 of the four wing stands, so I have eight more holes to drill in the two remaining stands (4 per stand), and then comes the priming and painting. Guess I also forgot to mention that I cleaned them up with acetone to remove this really dirty coating on the posts that must be from some sort of packing oil or something. That seemed to do a pretty good job of removing the residue. Looks like we get some good warm weather here for a change this week so I expect to complete the priming and painting, and perhaps even get them mounted to the floor by next weekend.
So no glaring posts about completing major airplane parts this week, but I am getting the small steps done to blast these wings out as quickly as possible. One step at a time.......
First pic is of the bottom of the wing stands. Note how the welds have been ground down so they are flush with the bottom of the flanges. Since one of the two welds performed on each angle bracket was on the bottom, these welds have to be ground down so that the stand will sit level on the concrete floor of the garage.
Aaron had already done a great job grinding down 3 of the four stands while they were still at his house before I loaded them up in the car for the ride home several weeks ago. The last one still needed to be done as shown in the pic below:
In addition to grinding down the bottom welds, Aaron had told me to cut wedges in the flanges of the angles to avoid catching your foot on them. Since his Dad's plasma cutter was not cooperating with the generator on the day they were welded to the posts, we resolved to use a reciprocating saw with a metal cutting blade to do the job. This, in addition to the grinder and an abrasive 3M wheel to clean the weld joint and remove corrosion, were the tools utilized this weekend as shown below:
The abrasive wheel is chucked in the drill. The metal blade in the recip saw really worked well to trim the flanges. It was a little bit of a trick to figure out how to hold the saw blade to trim only one flange at a time. Even more amazing was how this saw blade basically cuts through 1/4 inch thick steel with relative ease. I have used the recip saw for a variety of projects over the years, and I sort of have a love/hate relationship with the thing. In some instances it has almost broken my arm, and in other instances it works just fine with no problems whatsoever. Luckily the latter was the result on this particular project.
Here is a shot of the finished cuts from the saw. Basically I am just cutting a 45 degree angle or so on each vertical flange of each angle. Not shown yet is that I then took the grinder and removed all the sharp cut edges on each cut. The hope is that I will not catch my foot or cut myself on these while I work around the wing.
I then marked the positions for the mounting holes on the bottom of each flange, and per information from Aaron as to how he did this, I purchased a set of titanium bits with a pilot tip (DEwalt) that are 2 inches in from the edges of each angle, centered at 7/8 inches from the edge. Keep in mind that the angles are 2x2 inches wide, and 18 inches long. So you might think that the holes need to be centered at 1 inch centers. However, you alos ahve to keep in mind that they are 1/4 inch thick, and that 2x2 inch measurement is from the outside edge of each angle, so it does not account for the 1/4 inch thickness of each flange. So you need to measure the center point for the mounting bolt hole based on the inside distance of the angle, or 1 and 3/4 inches. This puts the centers at 7/8 inches from the outer edge. I then drilled a pilot hole with the 1/4 inch drill bit and was amazed again at how well the bit drilled through the still flange. I used some boe lube wax to help lubricate the bit. I then followed up with a 1/2 inch bit. Even though the anchor bolts I am using are only 3/8 inch bolts, Aaron suggested that I drill 1/2 inch wide bolt holes in the angles to allow some wiggle room in case the anchors are misaligned slightly from perfect 14 inch centers, which is highly likely.
I got the mounting holes drilled in 2 of the four wing stands, so I have eight more holes to drill in the two remaining stands (4 per stand), and then comes the priming and painting. Guess I also forgot to mention that I cleaned them up with acetone to remove this really dirty coating on the posts that must be from some sort of packing oil or something. That seemed to do a pretty good job of removing the residue. Looks like we get some good warm weather here for a change this week so I expect to complete the priming and painting, and perhaps even get them mounted to the floor by next weekend.
So no glaring posts about completing major airplane parts this week, but I am getting the small steps done to blast these wings out as quickly as possible. One step at a time.......
Monday, January 14, 2013
Wing spars relocated back on the work bench
As part of my ongoing major re-organization effort of the garage, I managed to clear off enough space from the work benches to allow me to move the spars from the shelf on the wall to the benches. I had not seen them for a while, and it felt good to get them down from "storage" so I can start match drilling ribs and skins and such.
The only problem I encountered whne attempting to move them from the shelf to the bench was that all of the parts that were stored on the shelf had been buried by almost 1 inch of shingle remnant when the jerks put my new roof on the house. THey did a great job cleaning up around the perimeter of the house but nobody even mentioned anything about checking and cleaning up my garage. This really pissed me off, but at the same time I realized that this was mostly my fault for leaving them "in harms way" adn not covering them with a tarp or something. I guess I just did not expect to ahve that much crap fall down into the garage.
IN any event, it looks like I was able to vacuum up most of the stuff, but this kind of thing always makes me nervous when I start thinking about all the little pieces tht may still be buried underneath the metal that will not show their ugly face until the vibration from the finished plane finally jars them loose, adn then who know what crevace they may find to deposit themselves into that end up affecting a critical flight control or something.
Here is the first of several pics - lovely shingle crap and sawdust all over my left elevator, and most certainly inside the bay where the electric servo and linkage goes - the one place that I really don't want to have any of this crap in my airplane, where it can be fatal if something goes wrong.
Edit - and a happy new year to me!! Turns out that blogspot has had problems with uploading images apparently since clear back on January 4. Smells like a virus or even better a ploy to push users away from IE and onto Google chrome or Firefox browsers. Having recently had problems at work with Firefox's latest release, I am now leary of downloading anyone's browser. That said, it does seem that Firefox v 17.0.1 does not have the problem that IE does (do NOT under any circumstances install Firefox v 18.0 - very bad!).
Anyway, to continue - here is the pics of my roof debris covered airplane parts, starting with the left elevator:
Next is the rear spar:
And on a happier note, here are the main wing spars back on the bench. Unfortunately, my HS is still on the table in front of the bench, and I need to finish up some touch up work on the HS so I can hang it back up on the wall to free up the table so I can start attaching ribs - it just never ends.
Still dealing with another deep freeze that has put the stops on anything in the garage. Now working on the cleanup of the benches in the basement - getting tired of living in the junk heap of a house. Almost ready to break out the two fire pits that I own and start some serious burning!
And finally, this is better late than never I guess. A couple of weeks ago I attended a hangar party up at KBJC for a gathering of RV folks across the state. Compliments to Bob Market, who owns this awesome hangar which will soon house Ron Duren's RV-7. I met several people that I had never met before, and made some new friends along the way. Here is a list of things that happened up there:
1. Got a close up view of Sean Thomas' Metal Wing stands. I will post some additional pics of that in another post, but here is a teaser pic for now. Sean is doing a great job.
2. Finally got to see Sean B, who had some very bad luck last summer after his house, and nearly completed RV7 were lost in a large fire near Colorado Springs. It was really great to see him and to find out that he is actually back to building another 7 again and doing his best to put the fire behind him. Kudos to you Sean. I admire your intestinal fortitude! KPR my friend.
3. I got to meet Jim Gray, owner and builder of the 2010 grand champion homebuilt award at Oshkosh for his beautifully finished RV-8, which was finished in the colors of the Jolly Roger Squadron seen in so many movies, including Top Gun and GI Jane. I took a ton of pics and got to pick Jim's brain for some building tips for such things as the forward baggage door, etc.
4. As if that was not enough, I then got a chance to talk with Bob Markert, who is now working on his fuselage. Get ready for alot of green - I just love the color of the primer he is using:
Note the mockup of the instrument panel - alot of Garmin goodies going in this one. He also has a rear seat throttle that I am also considering putting in the back as a safety feature more than anything else. I am NOT going to put the rear rudder pedals in mine - too many stories from other folks about ineffective control and uncomfortable foot position for the rear seat occupant. here is the forward throttle quadrant - very similar to what I am going to do.
And the rear throttle:
And here is shot of an improvement over the stock landing gear provided by Vans - Grove lnding gear struts are made from one piece leaf spring steel (I think), and they are designed to carry the hydraulic brake fluid inside the actual strut instead of from a separate brake line that is typically strapped to the the landing gear strut. These also serve to eliminate the need to make fairings for the landing gear legs since they already come aerodynamically shaped.
And finally a shot of one of the auxiliary fuel tanks that fit at the tip of each wing. These are from SafeAir and are very expensive (about 1500.00 for the pair), and they give you about an hour of extra fuel. I plan on getting the bungle kit which is simply the fuel line fitting that is added to the main fuel tank which connects to the fuel line coming from the aux tank shown below. I will simply cap this off for potential future use shold I decide to add the aux tanks at a later time. Part of the tank fits inside the wing tip (bottom of pic), and the rest of it (long tube) fits inside the lightening holes of the outer wing ribs. It was very cool to see these up close.
Then Bob showed me a custom windscreen that he ordered from the same company that makes the canopies for Vans. The stock canopy comes molded as one full unit that must be cut and trimmed to create the wind screen and the separate bubble canopy. I had no idea that you could order just the wind screen by itself. I learn something every day.
So it was one hangar, good friends, good food, good conversation, and a mind blowing awesome experience to see flying RVs and RVs under construction all in the same place. It certainly had an airplane factory feel to it. Now I just need to get back to pounding some rivets! All for now.
The only problem I encountered whne attempting to move them from the shelf to the bench was that all of the parts that were stored on the shelf had been buried by almost 1 inch of shingle remnant when the jerks put my new roof on the house. THey did a great job cleaning up around the perimeter of the house but nobody even mentioned anything about checking and cleaning up my garage. This really pissed me off, but at the same time I realized that this was mostly my fault for leaving them "in harms way" adn not covering them with a tarp or something. I guess I just did not expect to ahve that much crap fall down into the garage.
IN any event, it looks like I was able to vacuum up most of the stuff, but this kind of thing always makes me nervous when I start thinking about all the little pieces tht may still be buried underneath the metal that will not show their ugly face until the vibration from the finished plane finally jars them loose, adn then who know what crevace they may find to deposit themselves into that end up affecting a critical flight control or something.
Here is the first of several pics - lovely shingle crap and sawdust all over my left elevator, and most certainly inside the bay where the electric servo and linkage goes - the one place that I really don't want to have any of this crap in my airplane, where it can be fatal if something goes wrong.
Edit - and a happy new year to me!! Turns out that blogspot has had problems with uploading images apparently since clear back on January 4. Smells like a virus or even better a ploy to push users away from IE and onto Google chrome or Firefox browsers. Having recently had problems at work with Firefox's latest release, I am now leary of downloading anyone's browser. That said, it does seem that Firefox v 17.0.1 does not have the problem that IE does (do NOT under any circumstances install Firefox v 18.0 - very bad!).
Anyway, to continue - here is the pics of my roof debris covered airplane parts, starting with the left elevator:
And on a happier note, here are the main wing spars back on the bench. Unfortunately, my HS is still on the table in front of the bench, and I need to finish up some touch up work on the HS so I can hang it back up on the wall to free up the table so I can start attaching ribs - it just never ends.
Still dealing with another deep freeze that has put the stops on anything in the garage. Now working on the cleanup of the benches in the basement - getting tired of living in the junk heap of a house. Almost ready to break out the two fire pits that I own and start some serious burning!
And finally, this is better late than never I guess. A couple of weeks ago I attended a hangar party up at KBJC for a gathering of RV folks across the state. Compliments to Bob Market, who owns this awesome hangar which will soon house Ron Duren's RV-7. I met several people that I had never met before, and made some new friends along the way. Here is a list of things that happened up there:
1. Got a close up view of Sean Thomas' Metal Wing stands. I will post some additional pics of that in another post, but here is a teaser pic for now. Sean is doing a great job.
2. Finally got to see Sean B, who had some very bad luck last summer after his house, and nearly completed RV7 were lost in a large fire near Colorado Springs. It was really great to see him and to find out that he is actually back to building another 7 again and doing his best to put the fire behind him. Kudos to you Sean. I admire your intestinal fortitude! KPR my friend.
3. I got to meet Jim Gray, owner and builder of the 2010 grand champion homebuilt award at Oshkosh for his beautifully finished RV-8, which was finished in the colors of the Jolly Roger Squadron seen in so many movies, including Top Gun and GI Jane. I took a ton of pics and got to pick Jim's brain for some building tips for such things as the forward baggage door, etc.
4. As if that was not enough, I then got a chance to talk with Bob Markert, who is now working on his fuselage. Get ready for alot of green - I just love the color of the primer he is using:
And the rear throttle:
And here is shot of an improvement over the stock landing gear provided by Vans - Grove lnding gear struts are made from one piece leaf spring steel (I think), and they are designed to carry the hydraulic brake fluid inside the actual strut instead of from a separate brake line that is typically strapped to the the landing gear strut. These also serve to eliminate the need to make fairings for the landing gear legs since they already come aerodynamically shaped.
And finally a shot of one of the auxiliary fuel tanks that fit at the tip of each wing. These are from SafeAir and are very expensive (about 1500.00 for the pair), and they give you about an hour of extra fuel. I plan on getting the bungle kit which is simply the fuel line fitting that is added to the main fuel tank which connects to the fuel line coming from the aux tank shown below. I will simply cap this off for potential future use shold I decide to add the aux tanks at a later time. Part of the tank fits inside the wing tip (bottom of pic), and the rest of it (long tube) fits inside the lightening holes of the outer wing ribs. It was very cool to see these up close.
Then Bob showed me a custom windscreen that he ordered from the same company that makes the canopies for Vans. The stock canopy comes molded as one full unit that must be cut and trimmed to create the wind screen and the separate bubble canopy. I had no idea that you could order just the wind screen by itself. I learn something every day.
So it was one hangar, good friends, good food, good conversation, and a mind blowing awesome experience to see flying RVs and RVs under construction all in the same place. It certainly had an airplane factory feel to it. Now I just need to get back to pounding some rivets! All for now.
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