Wings
Strut attachment brackets (fix), is at the end of this section
5 Feb 2012 The first thing I did was build a flat table 16' long out of fabricated I-Joists, 2x4's, and 4x8' sheets of MDF. It should be a great surface to work on, and then it can be used to start the Bearhawk fuselage someday.Hours: 1.0
6 Feb 2012 Began constructing the wings. First I cut a small piece off each end of the spars to ensure a flat end (not sure how flat the ends come from the store). I then measured, marked and cut the small notches on one end (the inboard side) of each and the cut the ends (outboard side) with the dimensions called out in the plans. I used my electric mitre saw at the end of the table, with the spar ends going straight in and positioned for the cut. I was careful to get very accurate cuts, even though it appears by the plans, these need not be accurate, as the covering will traverse from the last rib to the outside (1" x 1") piece, but I wanted to be as accurate as possible.Hours: 1.0
15 Feb 2012 I jigged up my table saw and ripped a small edge off the top of the rear spar for the right wing. The ribs were just a bit tight. This now allows them to just slide on and the small angle I trimmed off is in keeping with the small angle on the top of the ribs.Hours: 1.0
6 Feb 2012 Began constructing the wings. First I cut a small piece off each end of the spars to ensure a flat end (not sure how flat the ends come from the store). I then measured, marked and cut the small notches on one end (the inboard side) of each and the cut the ends (outboard side) with the dimensions called out in the plans. I used my electric mitre saw at the end of the table, with the spar ends going straight in and positioned for the cut. I was careful to get very accurate cuts, even though it appears by the plans, these need not be accurate, as the covering will traverse from the last rib to the outside (1" x 1") piece, but I wanted to be as accurate as possible.Hours: 1.0
15 Feb 2012 I jigged up my table saw and ripped a small edge off the top of the rear spar for the right wing. The ribs were just a bit tight. This now allows them to just slide on and the small angle I trimmed off is in keeping with the small angle on the top of the ribs.Hours: 1.0
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26 Feb 2012 Cut and glued some 3/16" Finnish birch plywood to the inside ends of the right wing spars, as per plans. When the epoxy dried, I sanded these in prep for the inside ribs.Hours: 1.0
29 Feb 2012 Drilled the 3/16" and 1/4" holes in the spars. I moved the inboard most 3/16" hole approximately 3/4" to the side, so as not to interfer with the rib. The reason for this is because the original rib design did not call for a vertical piece where the spar comes thru, however the full size plans calls for a piece there. I like the vertical pieces on the ribs so I included those, and moved the hole to accomodate the rib.Hours: 0.5 8-14 March 2012 Using the template for the longer center wing spar support brackets, I cut out 4130, .08 steel brackets. I epoxied plywood plates to each side of the spars in the center and then, using the brackets, drilled the holes to accomadate these. I then started working on trimming the ribs as required to fit over the brackets and trimmed the tail pieces off the ribs using a very solid jib, which resulted in very consistent tail ends on the ribs. Hours: 2.0
15-19 March 2012 Began sliding the ribs on and fitting as necessary. The center rib and inboard end rib had to be notched to accomodate the plywood on both sides of the spar. I notched these ribs and fit them in place. Then it was just a matter of sliding the other ribs on. The ribs on the inside were a tight squeeze over the inside plywood, but with a little trimming they all fit. I then spent a few evenings spacinging the ribs so the cross wires would not hit any ribs and rub. I used twine in palce of the wire. The spacing is coming out very close to the plans. Hours: 2.0
29 Feb 2012 Drilled the 3/16" and 1/4" holes in the spars. I moved the inboard most 3/16" hole approximately 3/4" to the side, so as not to interfer with the rib. The reason for this is because the original rib design did not call for a vertical piece where the spar comes thru, however the full size plans calls for a piece there. I like the vertical pieces on the ribs so I included those, and moved the hole to accomodate the rib.Hours: 0.5 8-14 March 2012 Using the template for the longer center wing spar support brackets, I cut out 4130, .08 steel brackets. I epoxied plywood plates to each side of the spars in the center and then, using the brackets, drilled the holes to accomadate these. I then started working on trimming the ribs as required to fit over the brackets and trimmed the tail pieces off the ribs using a very solid jib, which resulted in very consistent tail ends on the ribs. Hours: 2.0
15-19 March 2012 Began sliding the ribs on and fitting as necessary. The center rib and inboard end rib had to be notched to accomodate the plywood on both sides of the spar. I notched these ribs and fit them in place. Then it was just a matter of sliding the other ribs on. The ribs on the inside were a tight squeeze over the inside plywood, but with a little trimming they all fit. I then spent a few evenings spacinging the ribs so the cross wires would not hit any ribs and rub. I used twine in palce of the wire. The spacing is coming out very close to the plans. Hours: 2.0
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20-25 March 2012 Once again the ribs had to come off (now that the spacing was correct), in order to trim the ribs which sit over the steel hardware. I had to wait until I knew exactly where the center rib would be located so a notch could be cut out to accomodate the bracket. Once I had significantly suffered enough cuts to my fingers, I threw the ribs back on and started epoxying. Meanwhile I fashioned a jig to drill the trailing edges of my ribs. After contemplating for a long time, I had finally decided to attach the trailing edges with the dowel and expoxy method. For the trailing edge itself, I plan to use the molding pieces I bought at Home Depot, and sand them accordingly. I felt the dowel system would be one of the strongest, lightest and most inexpensive way to go, but mostly the strongest. My researched (and experience) has always indicated, the dowel attachment method is extremely strong. The only problem is drilling extremely straight holes. Again, my expeience is that home made jibs are far superior over expensive store bought models. Those do a good job on very standard demention type wood, however, when it comes to the odd sizes on the Piet, its time to make our own. I grabbed a pices of hard wood, measured and cut out the jig. I then drilled a very straight hole and inserted a hollow brass dowel. The holes it drilled are extrememly accurate and should work fine for the trailing edge.For the leading edge, I plan to use 14' pieces of hand rail I've purchased at HD. In preparation, I forgot I needed to prepare the backside of the leading edges for the 8-32 bolts and nuts which will be attached, I purchased a small sanding disk which I put in my ordless drill. The backs of the leading edge were done in about 5 mins. Hours: 4.0
3 April 2012 Made for inside wing spar brackets out of .08 Chrome Moly. I drilled an fit all bolt holes except the connecting hole for the center section. I will drill these later when the CS is complete. Hours: 1.0
Shop Snacks have been resuppplied! Long live the Twizzlers!
3 April 2012 Made for inside wing spar brackets out of .08 Chrome Moly. I drilled an fit all bolt holes except the connecting hole for the center section. I will drill these later when the CS is complete. Hours: 1.0
Shop Snacks have been resuppplied! Long live the Twizzlers!
Trammeling the right wing...
20 June In order to trammel the right wing, I purchase an 8' long piece of aluminum channel molding and welded up a couple of trammeling pointers (not sure what they are really called). I also took off all the brackets from the right wing and powder coated them with white paint. I also put two coats of varnish where the brackets will go. Next I will reattach the brackets and start fashioning the cables, loosely on the inside of the right wing, in preparation for trammeling.Hours: 3.0
20-24 June I replaced the brackets on the right wing and got some help from my buddy Liam Albricht to help me make cables out of 3/32", Stainless Steel (SS), 7/19 cable. I attached AN115-21 shackles to the outboard end of each cables, and AN130-16S turnbuckles to the ends meeting in the middle, a total of four of each were needed. I then tightened up the turnbuckles until they were tight and made a solid "thump" when thumbed. I checked the trammeling measurements, still all good.Hours: 2.0
20-24 June I replaced the brackets on the right wing and got some help from my buddy Liam Albricht to help me make cables out of 3/32", Stainless Steel (SS), 7/19 cable. I attached AN115-21 shackles to the outboard end of each cables, and AN130-16S turnbuckles to the ends meeting in the middle, a total of four of each were needed. I then tightened up the turnbuckles until they were tight and made a solid "thump" when thumbed. I checked the trammeling measurements, still all good.Hours: 2.0
Right Wing Trailing Edge...
2 Jul 2012 For the wing trailing edges I purchased several 8' long pieces of very straight molding from HD in the shape I could use for the last few inches of the trailing edge. On the table saw I made a fence and ripped a straight edge along the front side. The piece in the picture shows a before and after. The before also show the edge with a crack on the end. This was a very straight piece and the last few feet will be cut off anyway, so the crack, which is only about a 1/4-1/2" deep anyway, will not be a factor.Hours: 1.0
10 Aug 2012 Sanded the right wing trailing edge bottom side a little more. **I measured with a flat ruler again and found the trailing edge not quite flat on the bottom, so another 30-40 minutes of sandings and the entire bottom was a lot more flat, and no gaps when a straight wedge was laid across the bottom side of ribs onto the trailing edge.Hours 1.0
10 Aug 2012 Sanded the right wing trailing edge bottom side a little more. **I measured with a flat ruler again and found the trailing edge not quite flat on the bottom, so another 30-40 minutes of sandings and the entire bottom was a lot more flat, and no gaps when a straight wedge was laid across the bottom side of ribs onto the trailing edge.Hours 1.0
Right Wing Aileron...
15 July 2012 - 31 July 2012 Took a small break for Brodhead and Oshkosh 2012. Worked on the right wing aileron section. Prepped, cut and glued in the small spar for the forward side of the aileron. Placed the small pieces of capstip across the top (I used 1/4" x 1/2" to match the small spar width). I made a template then cut a piece of 1/16' plywood for the inside rib next to the aileron and glued in place.Hours: 4.0
1 Aug 2012 - 6 Aug 2012 Finished sanding the small aileron rear side. Made a template exactly like the end plate above. Cut out pieces and glued them to make the end cap for the right aileron, for the inboard end. This apparently gives the aileron more rigidity and surface area for the covering material down the line.Hours: 2.0
20-25 Aug 2012 Epoxied on the aileron trailing edge. Sanded the top side thoroughly to conform as closely as possible to the wing trailing edge. For the trailing edge I would use a pencil and scribble evenly alone the top or bottom side, so when I went to sand, I could see where I had sanded, which gave me good consistent surfaces.Hours: 2.08-11 Oct 2012 Worked on the aileron spars. For the front spar, I cut a beveled angle at the plans recommended angle and will glue spacer pieces on top and bottom to match. This way, when cut off the hinges will fit flat.Hours: 2.0
1 Aug 2012 - 6 Aug 2012 Finished sanding the small aileron rear side. Made a template exactly like the end plate above. Cut out pieces and glued them to make the end cap for the right aileron, for the inboard end. This apparently gives the aileron more rigidity and surface area for the covering material down the line.Hours: 2.0
20-25 Aug 2012 Epoxied on the aileron trailing edge. Sanded the top side thoroughly to conform as closely as possible to the wing trailing edge. For the trailing edge I would use a pencil and scribble evenly alone the top or bottom side, so when I went to sand, I could see where I had sanded, which gave me good consistent surfaces.Hours: 2.08-11 Oct 2012 Worked on the aileron spars. For the front spar, I cut a beveled angle at the plans recommended angle and will glue spacer pieces on top and bottom to match. This way, when cut off the hinges will fit flat.Hours: 2.0
Compression braces...
5 Aug 2012 I had looked at the wing plans and thought they called for one 3/4" x 3/4" compression brace from the front spar to the rear spar where the center cross brace wires connect to the spars in the middle. Later I discovered there were supposed to be two braces (one on top and one on the bottom).....just like the picture I had overlooked. Oh well, another lesson learned. I chose to leave the extra piece in place as it won't add much weight, and ripping it out would have caused my damage then I wanted to risk. I then started to epoxy in the upper and lower braces.Hours: 0.524-25 Oct I cut support braces for the right wing, to the in-board rib. To provide support for the braces, I first cut some pywood and epoxied to the inside of the rib. Then I cut three braces out of 1/2" x 1/2" spruce and a support piece out of plywood, where the three braces would come together on the rib.Hours: 0.5
Wing Leading Edge (right)...
Here are some pictures of the leading edge production (right wing only). I made the leading edge from a 16' piece of stair rail I purchased from HD. I found the straightest piece I could find. I made a template of the leading edge I wanted to use, then I set about making jigs on the table saw to cut it to shape.
10 - 19 Nov 2012 Building the leading edge continues, very slowly after missing a week or two with other commitments. A lot of time was alloted to figuring out the best way to drill straight, and consistant hole through the leading edge. I made a couple of jigs and one seemed to work the best (and of course it was the simplest as is usually the case). The holes came out great and my SS screws fit nicely. After a few practice fits, I turned to cutting a groove for the 1/16" plywood for the leading edge. I rigged up several jigs on the table saw and ran the leading edge thru, making a notch for the leading edge of the plywood. This will give a "ledge" for the plywood to sit on and be epoxied. There was a lot of work involved in this, for what seems like very little result, but I think this was an important aspect of the leading edge.
Wing Tip...
Jan 1 - Jan 4 Form a jig for the right wing tip. Over the course of a few days I cut 1/4' x 1" spruce, steamed and placed in the jig I had made using a spare rib. The tip was formed to have the same arc/camber as the ribs.Hours: 2.0
16 Jan 2013 Happy New Year! After the wing tip lamination set up, I took it out of the jig and started sanding, mostly by hand. I did use a belt sander on the inside of the bow (which will be inside the covering), however for the outside I made a small template and decided to sand by hand to the shape I wanted. A friend (Mic) stopped by last weekend and did a bit of sanding on the wing tip, giving me time to start sanding the leading edge to shape. I made a template (I forgot to get a picture) out of a piece of 1/8" plywood I used to ensure I got a symetrical front edge and it came out pretty nice I think.Hours: 8.0
22 Jan 2013 This weekend I finished sanding the wing tip bow, drilled hole for some SS 8-32 bolts which I counter sunk into the wood and attached the wing tip. Mickey had notched out the bow where it attached to each wing spar, this ensured it fit tightly up against each of the aileron spars in the back. I epoxied on the wing tip, let it dry over night then began sanding again. I formed the rear and front of the wing tip to the shape I wanted, on the top side. I will have to flip the wing to sand the bottom side. I also cut and glued in the supporting braces. On each of these I like to make small blocks out of 1/8" plywood so they seat a little firmer. I then filled the holes on the wing tip where the two screws were counter sunk and sanded these when dry. On the top front of the wing I had also applied some epoxy with filler, and sanded the contour into shape to make a smoother transition to the wing tip.Time to flip the wing again and begin sanding the bottom.Hours: 6.0
3 Feb 2013 Quick update. Its Super Bowl Sunday!! Flipped the wing over and got ready to sand the bottom of the wing, then I remembered I needed to add cap strip along the leading edge of the aileron. So I cut cap strip and epoxied it all in, using a bunch of Bronze weights to hold them on place. Once dry I will start sanding the bottom of the wing.Hours: 1.0
7 Feb 2013 Not much new to post, I just sand another section each night. Last night Mic stopped by and put a few hours in sanding off the burrs and edges off the bottom. Tonight I finished sanding the aileron outer and front edge capstrips. I probably over analiysed this, but where the clothe covering would attach over the front edge of the aileron I wanted to ensure a smooth transition from the last inside capstrip to the outside wingtip bow. The last picture here shows my highly technical tool I made to simulate how the clothe would touch and sanded until it was the way I wanted.Hours: 1.0
8-11 Feb 2013 Sanding, Sanding, Sanding. On Saturday, Mickey stopped by to help again with the sanding. He formed the leading edge of the wingtip and worked a lot of the ribs, taking off sharp edges and removing drips of epoxy. I faired the trailing edges on the bottom side and the leading edge. On the aileron and on some of the rib bottoms where it met the leading edge, I used some epoxy mixed with west system micro balloons fairing powder (brown) and filled in some spots which didn't join perfectly. I put this stuff on pretty thick (a lesson learned from putting on thin coats only to sand off and have to repeat several times). Anyway, it looks awful at first, but with the fairing powder mixed in, it sands very easily, and I only use to fill low spots, not for anything structural (although it doesn't loose much strength with the powder). I then sanded these areas smooth. On the leading edge, I first sprayed on sandable primer, so when I take my sanding block to the leading edge, I can tell where I am sanding. I transitioned from a small block to a 12" block, then to a three foot contoured block. The leading edge came out extremely straight and consistent.Hours: 4.0
Aileron Hardware...
16-17 Feb 2013 Finished sanding most of the bottom of the wing, where I had touched up with some filler. I turned my sights to the remaining aileron metal parts. First I looked at the outter aileron pully. I really did not like the small tabs which are brazed on to hold the 2" pully wheels. Instead I decided to make two brackets, one slight smaller then the other, which in effect hold the wheel the same, but once welded should be much much stronger. I will wait the weld these later and drill the holes, but only after finishing the aileron horn, so I can adjust the angle of the pully brackets first. For the metal, again it was 4130 chrome molly @ .06"Next I started on the aileron horn. I made a template and cut two horns out of .032 4130 sheet metal. I then pinched them in a vice along with a solid piece of rod, and hammered the leading edges over by eye, and also bent the attachment flanges out 90'. Once these are finished I will go ahead and weld them up.Hours: 2.0
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23-24 March: To install the right aileron horn and the associated pulleys, first I spent an inodinate amount of time alligning both, so the cable would run out of the pulleytraight back. Holding the bracket in place with the wheel offset, and the horn level perpendicular, etc, I got good positions, marked and drilled both. I then made small adjustments to the angle of the pulley bracket so the wheels pointed exactly level with the horn attachment holes. Finally, after this was done, I made a tab for the back of the aileron horn and will weld that up.Hours: 2.0
Left Wing
Working the left spar
1-15 Feb 2017 - Finished varnishing the first (right) wing.Hours: 2.0
1-15 March 2017 - LEFT WING!!I put together/rebuilt the second table in my shop and started laying out room for the left wing. I had previously trimmed the ends of the spars (when I did the right wing), so all they needed was to have the top/bottom trimmed a fraction to allow the ribs to slide on easily (the same technique I used successfully for the right wing). But befor doing this, I cut and glued on the center brace support plywood pieces. This should have been done after trimming the spar, but I did not have my shop ready to run the spar across the table saw, and wanted to accomplish something this week end. It was not a problem when I went to trim the spar. I simply set up stands at the same height as the table saw, then carefully run it thru, only taking off a fraction at a time, until a few ribs slipped on nicely. I tried a few ribs, in case the one sample I grabbed was the odd ball.Hours: 1.0
1-15 March 2017 - LEFT WING!!I put together/rebuilt the second table in my shop and started laying out room for the left wing. I had previously trimmed the ends of the spars (when I did the right wing), so all they needed was to have the top/bottom trimmed a fraction to allow the ribs to slide on easily (the same technique I used successfully for the right wing). But befor doing this, I cut and glued on the center brace support plywood pieces. This should have been done after trimming the spar, but I did not have my shop ready to run the spar across the table saw, and wanted to accomplish something this week end. It was not a problem when I went to trim the spar. I simply set up stands at the same height as the table saw, then carefully run it thru, only taking off a fraction at a time, until a few ribs slipped on nicely. I tried a few ribs, in case the one sample I grabbed was the odd ball.Hours: 1.0
Adding ribs...
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Oct and Nov 2017 Fitted the ribs and glued. After the ribs were added, we began our move back to Maryland.Hours: 3.0
Left wing Wire Bracing...
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Dec 2017 - Jan 2018 New Years! Manufactured and installed left wing cross brace metal pieces and bracing wires.Hours: 4.0
Left Wing: trailing edge and Aileron...
an 2018 - Repeating the procedures from the right wing, I drilled the holes for the trailing edge of the left wing, using the same jig. I then started on the aileron while I waited on my wood order from ACS and my wood I needed from HD for my trailing edge. I sanded off the inside of the ribs to accept the back edge stringer of the wing. Lots of extra epoxy was removed, then it slid right into place. I clamped and epoxied it.Hours: 2.0
March 2018 Have not been keeping up with blogging, so some pictures may be out of order. Worked on left wing trailing edge and aileron some more. Pictures show a few of my techniques. For sanding trailing edge, I use priming sander to get good even sanding results. For the trailing edge piece I use my second drilling jig. I show it here just that it matches the end of the ribs. I temporarily hold attahce the trailing edge and scribe the small line on top of the end of each rib, onto the trailing edge. I then use the drilling jig and easily align it to each line on the trailing edge and simply drill the hole. On the jib I have also placed a mark to calibrate how deep to drill each hole. I then cut lengths of appropriate sized dowels, slightly smaller then both holes total, to allow space for the expoy. Then simply epoxy the trailing edge on. When it dries, again I use sanding primer to sand the trailing edge to conform with the ribs.Hours: 6.0
March 2018 Have not been keeping up with blogging, so some pictures may be out of order. Worked on left wing trailing edge and aileron some more. Pictures show a few of my techniques. For sanding trailing edge, I use priming sander to get good even sanding results. For the trailing edge piece I use my second drilling jig. I show it here just that it matches the end of the ribs. I temporarily hold attahce the trailing edge and scribe the small line on top of the end of each rib, onto the trailing edge. I then use the drilling jig and easily align it to each line on the trailing edge and simply drill the hole. On the jib I have also placed a mark to calibrate how deep to drill each hole. I then cut lengths of appropriate sized dowels, slightly smaller then both holes total, to allow space for the expoy. Then simply epoxy the trailing edge on. When it dries, again I use sanding primer to sand the trailing edge to conform with the ribs.Hours: 6.0
Working on left wing: Finishing leading edge. Leading edge plywood. Wing tip bow...
May - July 2018 - Worked periodically on the left wing leading edge. Finished sanding both top and bottom. I then drilled the holes for the leading edge bolts. There is not much room to work with, even with a 90' drill, so I started with a short bit, got the hole started, then the longer bit would fit it and I completed each hole. On the outside, leading edge front face, I counter sunk enough to allow for the bolt head to be recessed. **I first incerted a dowel, so the tip of the fosner bit would have sort of a guide, and it worked pretty good. Prepared the plywood for the to p of the leading edge. Used a simpilar approach to holding it on while gluing, I simply used clamps this tim, seemed to work fine. I then prepared the four pieces of plywood, gluing each one by one (one per night), and trimming off any extra epoxy so they would meet up on respective ribs and be flush together. I sanded these and feathered them onto the leading edge. I then turned to the wing tip bow. I once again used four pieces of 1/4" spruce, but left them all the same size preportionally, steamed them to about 25% over the camber I wanted (for spring back), then glued them all at once. It came out vey nice. **INstead of sanding this one first before attaching, I decided to attach first and the mirror the right wing bow. I epoxied the bow on then drill holes for later. I then made a hand made caliper so as I started sanding I could check the size with the right wing tip bow, to get fairly close to the same dimensions.Hours: 10.0
Strut attachments/addition
Note: When constructing the wings, I read where several builders made this wing attachment brackets without welding on the top tab (across the spar). At first this seemed reasonable, it doesn't seem to add any strength, while at the same time could be very hard to weld, possibly even weakening the metal or hurting the wood (if rounded or rubbing etc). Anyway, I also decided to fashion the brackets without welding the top tab.
Later on in my build, when I got ready to put the wings on, I researched this a bit more. I cam to the conclusion, this tab could possibly add some risidual strength. Even is there was a slight possibility, I thought it would be worth fixing this. So I made some additional brackets that attach to the same bolts (slightly longer) and it now provides the same structural integitry as is the tabs were weded on. In fact, I think my tabs are a much better way to approach this and only cost an ounce or two.
Later on in my build, when I got ready to put the wings on, I researched this a bit more. I cam to the conclusion, this tab could possibly add some risidual strength. Even is there was a slight possibility, I thought it would be worth fixing this. So I made some additional brackets that attach to the same bolts (slightly longer) and it now provides the same structural integitry as is the tabs were weded on. In fact, I think my tabs are a much better way to approach this and only cost an ounce or two.