GlasairProject.com TD to FT conversion

TD to FT Conversion: (click here for newest entries)

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05/8/2005 Task Hours: 10.0: I had the rest of the weekend to apply the laminates to the firewall nose-gear reinforcements. It's a good thing too. Each of these laminates are 23" by 9". Ten of them get laminated to each reinforcement rib. I spent 2 hours on Friday and another 5 hours on Saturday completing these laminations. Those ribs are stout! While doing this, I paid very close attention to the saturation of the cloth, keeping it as thin as possible in the 40lb foam areas. Overall, the spacing on the ribs came out to 6.12". This is about as perfect as I could get for the nose gear trunnion width.

Sunday was spent cutting the openings in the wing for the landing gear brackets and legs to mount in. Then I cleaned up the openings and jigged the B-rib mounts in place to check for clearance. I had to remove quite a bit of material in the area where the gear leg clamps mount to the B-rib jigs. After trimming I measured the remaining lower B-rib reinforcement thickness to verify that I had over the minimum 1" thickness. They both measured at 1.1" through this area. Again, it's about as perfect as I could get it.

When had them jigged in place and the clearances trimmed, I mounted the gear legs to the B-rib brackets and measured the center, A-rib, mount for clearance and gear leg alignment. Both axle positions lined up within .1" in height and setback.

I did find one problem. The A-rib mount was about 3/8" further from the right side B-rib bracket than the left side. I traced this problem to a mistake I made about 5 years ago. The first part I assembled was the wing. When I installed the A-rib, I managed to get the lower part of it tilted about 3/16" toward the left side of the plane. This causes the sliding portion of the A-rib bracket to sit almost 5/16" off the end of the gear leg. I'm working on a fix for this.

I may be able to lengthen the clamp portion of the inboard gear leg bracket with some more metal welded around the outside. This would retain the strength and add negligible weight. I would have to fill the extra space with a little more milled fiber, but I think it will work. I'll have to ask some qualified people.

Stay tuned....

05/15/2005 Task Hours: 9.0: Today I cut the slots in the firewall for the nose gear trunnion attach plates to pass through. After getting them sized correctly, I temporarily clamped them into place and measured for the nose gear trunnion attach bolt location. The spec is 7 1/8" from the fuselage bottom and 3/4" forward of the firewall. The 3/4" dimension worked perfectly, however the 7 1/8" dimension was another story. Again, the Subaru engine mount I fabricated introduced a minor issue. After much moving around of the nose gear, I was able to get everything to line up with the engine mount and only had to lower the bolt location by 1/4". I'll be able to match this change with the main gear, so I'll have a Glasair that will sit 1/4" higher than normal.

The next half of the day I decided it was time to destroy my beautiful Subaru engine mount. I started by locating where the new cross support tubes would pass through the existing tubing and attach to the lower cross-member. I clamped a piece of flat steel over the existing engine mount holes on the right side of the mount. On that plate I marked where the new tube would mount to the firewall. From there, I marked the trajectory that the tube would take through the existing tube. I attached an 18" long 1/4" drill bit to my drill. I have a unique hole saw mandrel that clamps to a 1/4" bit. I slid it half way up the drill bit and installed a 3/4" hole saw. I started a pilot hole in the first side of the existing tubing. After it was about half way though the first wall, I aimed the drill and bit towards the point on the lower cross tube where I had marked as the point where I wanted the new tube to interconnect. It was a slow process, but when it was complete, I had a snug hole to slide the new tubing through. The last picture here is the neat little tool I used to mark the end of the tube so that I could cut it to fit it's mounting location on the lower cross tube.

To finish the day, I cleaned the paint off of the underside of the lower cross tube where the upper shock mount plate will attach to the mount. I trimmed the shock mount tabs and the mount to fit together properly. Finally, I cut the four pivot weldments for the top of the upper shock mount plate.

05/20/2005 Task Hours: 8.0: I spoke with Cliff Faber Thursday about my gear leg length issue between the "A" and "B" rib mounting points. He came up with what appears to be a perfect solution that beats the modified "A" rib bracket idea I had.

He suggested applying additional 40lb foam between the "B" rib and attach bracket. I figure that 3/8" will do. Applying it to both "B" ribs will keep the gear symmetrical and give me plenty of gear leg remaining to trim at the "A" rib bracket.

The final 2-layer laminates will be applied over the added 40lb foam shim to tie them together with the upper and lower UNI rib reinforcements.

Thanks again Cliff!

05/22/2005 Task Hours: 5.0: Saturday I continued updating the engine mount for the nose gear upper shock bracket. I tack-welded the right cross tube into place, cut the tube to length and welded the tubing for the firewall bolt to go through. I proceeded to attempt to recreate my success on the left side. After accomplishing that, I welded the new upper shock mount together. I used the assembled shock mount to jig the lugs in position on the bottom of the engine mount. Once everything lined up, I welded the lugs to the engine mount. The next step was to weld the remainder of the engine mount modifications. Last I installed the engine mount and drilled the holes through the new tubes and firewall. I jigged the nose gear and upper shock mount plate into place and drilled the pivot holes through the shock mount and lugs. I officially have an operating nose gear leg!!

Next I worked on the modification that Cliff suggested for my gear leg problem. I cut two 40lb foam pieces to fit between the B-rib brackets and the B-rib. I sanded the front and rear edges to provide a smooth transition from the face of the rib onto the face of the foam for the final four-layer laminates. I bonded these in place with a medium mill-fiber mixture and clamped them to the B-rib. While they were curing, I mixed a thick q-cell batch and radiused the edges in all the rib laminate areas.

06/12/2005 Task Hours: 3.0: I spent a few hours Sunday cleaning up my 40lb foam laminations and q-cell edges and laminating the four-layer laminates to the "A" and "B" ribs as well as the two-layer laminates on the backside of the "A" rib. The front 5" of the laminations were rather difficult to do because of the holes for the control sick pivot, aileron push-rod and vent lines. I've decided that I will add another couple laminates to each of these areas from the main spar and completely over the 40lb foam added for the "B" rib brackets. For now I'm out of time.

06/18/2005 Task Hours: 8.0: After spending my evenings during the week refinishing the completed engine mount and nose gear hardware, I spent Saturday installing them. The first photo shows the mount and radiator reinstalled along with the coolant hoses in position. Next is a close up of the attaching hardware for the nose gear leg. Then another close up from a different angle. Photo four is the back side of the fire wall trunnion attach brackets. The white bracket in this photo is to attach the rudder cable springs. The last photo shows that we are definitely going back together... finally!

07/02/2005 Task Hours: 5.0: I started today by trimming the laminates around the rib attach brackets. Then I cleaned the gear legs with acetone and a drill-mounted scrubber to remove grease and flaking paint. I also had to clean the original bolt holes with acetone and then fill them with a resin and milled fiber mixture. Next I mounted the rib brackets and clamped them into place. Once the milled fiber was tacky, I mounted the legs in the brackets and aligned them per the instructions. Once aligned I tightened the clamps and filled all the voids with a resin and milled fiber mixture. The last thing I did today was drill four of the B-rib attach bracket holes and slip some screws into place so things won't move before I get the rest of the holes drilled. The photos were taken after the above steps were complete.

07/04/2005 Task Hours: 12.0: I spent Sunday and Monday finishing drilling the brackets, measuring for bolt lengths and reassembling the wing. Nothing was really exciting enough to take pictures of so I just took a bad picture of the wing before I left for the day Monday.

07/17/2005 Task Hours: 10.0: It was too warm this weekend to spend much daytime at the hangar. I did manage to squeeze in about seven hours after 8pm Saturday and another three hours early Sunday morning after catching a few hours sleep at home. Saturday I fabricated the lower wing skin stiffener channels and the main feed and return fuel lines for the new design fuel delivery system. Sunday morning I cleaned the mess behind the firewall and started reinstalling the brake lines. Then I put together my next list of items to purchase for my next building session.

08/07/2005 Task Hours: 12.0: I got up early Saturday morning and worked until 1pm. I managed to get the remainder of the fuel lines installed and finished fabricating my new positive battery cables for the upgraded EFI backup power system. Before going home I installed the rudder pedals and dual battery tray. Sunday was another early morning. This time I installed the batteries with the new cables and, finally, reinstalled the wing. Once the wing was in place, I installed the nose gear fork with the tire, finished drilling the holes for the main gear brackets and started replacing the temporary bolts in the B-rib brackets with the final assembly bolts.

08/14/2005 Task Hours: 6.0: Yet another hot weekend here in Oregon. Temps hit around 90deg Saturday and 94deg Sunday in Hillsboro. I managed to get up early Saturday and get to the airport before it was too hot to work. I finished installing the B-rib bracket and main gear bracket bolts. Then I installed the lower wing skin stiffener angles. The main gear legs were then set into place with temporary bolts and the axles with wheels installed. Once it was ready to stand on it's own, I remounted the engine.

08/21/2005 Task Hours: 12: It's always interesting to compare the amount of time it takes to disassemble something with the time to reassemble. It was a total of seven hours to remove the instrument panel, engine, wing and rudder pedals. As of today, I'm going on at least thirty-four hours to reassemble these parts, not including the gear conversion portion.

Saturday I reassembled the elevator trim, pitot static tubing and fuselage wiring. Sunday I managed to get all of the engine plumbing and electrical back in place.

Items remaining are to modify the exhaust to fit around the nose gear and properly install the axles with regards to the splice plates and final alignment.

From this point forward, I'm considering the conversion complete and will continue to update in the builders log.

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