Day 11 - working on the new fuselage (and more):

So...back to CorelDraw (CAD) to make a few changes. Thought about a way to make it jig a little better without twisting. This isn't a difficult build but since I was doing it I figured I'd try something "different". I added long tabs to the top of the fuselage that create a straight datum line from the wing-saddle back. The tabs will be glued into a block that echos the shape of the back of the fuselage and the whole thing will sit, inverted, on a flat surface.

Here's the fuselage parts being assembled using a straight-edge to keep the parts in line along the jig tabs:

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The second big change was to extend the pockets for the former tabs all the way through the doublers and part way into the fuselage sides themselves. The idea is to use the formers as alignment pins for the doublers:

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With everything assembled it all seems to work pretty nifty. I spent some time adding the doublers and 1/8" longerons to the sides. All the parts are there to finish assembling the fuselage as I get to it.

Also cut the 1/8" ribs at the poly break (4 total) and assembled the right side wing-tip.

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Day 12 - Wednesday

Assembling the second fuselage with the jig and long tabs concept. It seems to work. Everything seemed to have turned out dead square with no effort. The tail end of the fuselage mated perfectly with no fiddling.

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Gluing the bottom on was uneventful. The smaller tabs aligned it pretty well. Put a large flat weight on the middle over the wing saddle and taped the tail jig down. Everything still stayed straight and square. Fingers crossed it'll be like that tomorrow once it's all dry:

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Then back to the easy stuff - left wingtip panel done framed up and done except for trimming and sanding the ends.

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After a short delay, construction continues slowly. Wingtip leading edges are shaped and finished. Inboard section leading edges are roughed in to be finished after sheeting. Gussets installed. Will get to the joiner tubes/rods eventually.

Now on to joining the two inboard sections. The ply braces are a reasonably tight fit. Decided the best way to approach it was to use 30 minute epoxy and do one side first, one brace at a time, working from front to back while joining the two sides using the rear brace to make sure everything is aligned. The fit is good enough that it pretty much self aligns but I didn't want to chance it.

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All three braces glued up to the left wing panel. The right panel slides on reasonably well with no fiddling, so gluing it up shouldn't be a big deal.

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Joined the center panels. Everything was a good fit so it slid together easily and straight - used a lot of clamps to put it together:



Soon after started sheeting




Finished sheeting and started on the wingtip joiners. Scrounged up a couple pieces of matching music wire and tubing to make the joiner as per the plans. Got it all together and tacked the wire and tube with epoxy. CG calls for wrapping the two with fiberglass then epoxying. That seemed to work ok on my first GL so I'll probably go with it here too.

Finished the cross-grain sheeting on the bottom of the fuselage. Put a long straight-line on a piece of masking tape stuck to a heavy plate of glass then taped the fuselage down to the glass using centerline reference marks on the front former and building-jig plate. Clamped the tail-end of the fuselage together with a 1/8" spacer and verified it was on the center-line. To firm it all up the middle of the fuselage was weighted down. With everything appearing square I went ahead and glued up the cross-grain all the way to the tail and let it dry for a couple hours. Checked everything with a bubble-level and it appeared to be parallel with the glass, and the sides pretty much square.

Flipping everything over I installed the insert/spacer in the tail, with that dry I finalled trimmed off the building-jig plate. Everything still seemed straight - or at least a ton better than what I'd done before! Installed the top sheeting, let it dry, and sanded everything flush. Seems ok! Just need to do the cross-grain on the top and start wrapping up the details on the fuselage.

Back to the wing... got the tip-joiners done on both sides. Ended up with about a 1/16" difference in polyhedral between the two sides. Close enough for me.

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Suggested modification ( was suggested to me back in 1983) discard the wing mounting dowels, as per the plan, and add dowels across the fuselarge, one in front of leading edge and one behind the trailing edge. Sticking out of the fuselage about 10mm (3/8”) per side.
Allows 2 rubber bands fore to aft and 2 rubber bands diagonally - much safer and more secure wing mounting.
Have Just converted my 35 yr old GL to electric.

Too late for this one, but that's a relatively easy mod to keep in mind.

Closed up the front of the fuselage and finished the hatch.

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Now to get started on the nose-block. Made an outline of the side-profile to match the parts I'd made previously. Glued the outline down and used a band-saw to cut the nose block. Also hollowed it out on the drill-press prior to doing the shaping and opened the front former in case nose-weight is needed later.

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Glued it up and rough cut the top-view profile. I'll probably start in on the heavy sanding when I'm waiting for the tail parts to dry.

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Finished the rudder today except for the final shaping/sanding. Got silly with the CAD/CNC stuff though - made a little pocket for the gusset. It worked.

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While I was designing/cutting the 3/16" stuff I went ahead and cut the dorsal. Usually I find they just complicate the covering, but I thought I'd make one anyway. I was really happy that it fit perfectly without any sanding or effort. Hopefully I won't twist it up while covering.

Also modified the bottom of the vertical a little. The plans/kit call for a wedge to fill the gap between the bottom of the vertical and the fuselage/stabilizer. Instead I cut the bottom 3/16" block to fit around the front of the stabilizer and butt up directly onto the fuselage. Another gamble but it seems to fit ok:

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Finally - added the wingtip blocks. The tip-blocks were cut into 1"x1" with a 45° slant from some 1"-thick stock I had left over from my Sagitta project. I think the original design and kit use a more shallow angle so the tips end up being wider...the end result looks ok though:

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That completes the basic construction. Still need to 'glass the center section, do a lot of sanding, then finish sand for covering.

Covering... one tip done, tail done. So far I've only used Ultracote left over from other projects.











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I used pull-pull "cables" on my Spectra and they've worked great over the years:





I thought they'd also save weight in the tail on the GL so I planned to use them on this build too. When designing the fuselage parts I also planned in the servos, location for the "cable" exits, and location in the rear bulkhead for fairleads. On paper it looked good but I needed to make sure before I start covering.

For fairleads I used a couple pieces of nyrod, carefully cut so the interior didn't have any burrs. The holes for the two fairleads were cut into the plywood doubler prior to building the bulkhead:



The "cable" exits were marked with two holes. In the computer the slope of the "cable" was pretty shallow. I've opened both slots up, I'll probably just cut a small slit in the covering when I'm done as a final "exit":



No pictures yet, but - I put both pull-pull cables in and checked their location against the dorsal, fin, and rudder. Everything seems like it'll work!

Spent an afternoon sanding the fuselage to get ready for cover. Then realized I needed to think about a switch, and a few other things. I borrowed the switch-bracket design I made for my Mini-Antic and modified it for a smaller switch. Should do the job:






Then on to covering: was toying with doing something fancy on the fuselage and...no. Red. I'll add trim later. Now I really just want to get it done.

I haven't covered a glider nose in a long time so I kept things simple with four pieces. Based on my last couple of experiences I think I might have been able to wrap one piece from the top to around the two sides, but... nope, just keeping it simple. Started with one piece on the bottom that I wrapped a bit around the sides, then the two sides, then the top. It doesn't look horrible.

Originally Posted by vulturetec

Scratch building a Gentle Lady. Trying to make it a "quick build" project over Thanksgiving. We'll see!

Yes, it is an old thread, but thank you for sharing, and giving us the insight on CNC . The modern way of scratch building from wood..

Martin

Thanks Martin!

Hi Vulturetec, nice build, I want for some time to build a GL with a small 2,5cc glow engine with a limited amount of run time. I have the PDF's from OZ but I do not know to build from paper plans..... Is there a posibility to share the Cad files ? I know there was a lot of work involved.... Thanks