Still working the cowling-windscreen interface problems. The problems seem to stem from the configuration of the Polini Thor 303. The engine has its electric starter mounted on the forward port side of the engine slightly below the crankcase. this causes an interference problem with the front ring of the nice fiberglass bubble cowling such that there is little or no clearance for the prop. I purchased and modified a 30mm prop extender (Miniplane-USA, $65). This alleviates the clearance problem BUT moves the cowling forward on the air-frame such that the "Cheeks: do not extend to the welded fuselage mounting tabs. I can fix this problem by adding fiberglass extenders. HOWEVER, the aft cowling ring" which should meet the curve of the windscreen is about 3" too far forward leaving significant gap. I've been fighting (positioning, re-locating , etc.) for several days to little avail.
Engine with 30mm prop extender.
I have a local source of 3/32" polycarbonate sheet (~$40). The plan is to cut the new material into a shape that will provide the proper curve to meet the cowling and to trim the existing windscreen to accept ("bond") the new curved section in place. As of tonight, I am in the process of laying out and trimming the 3/32" sheet for the required 40" (curve dimension) to fit the cowling. I hope to complete the layout, cutting, trimming, and trial installation tomorrow (Saturday). Will post a report and more pictures then.
Kurt, would it be possible to cut the cowl left/right about 4 to 5 inches from the rear side edges? Then move the window section back where it needs to be and build a fiberglass filler to fill the cut section, basically making the cowl longer. Would that also work?
Todd presents a good option to correct your issue, but it may require a fair amount of finesse to then line the windshield end of the cowl back up with the rest of it.
You may want to consider backtracking a bit instead. How much of an overlap is there between the starter and the cowl lip? If it's not that much, it might be worth not using the prop extension plate and going back to square one. As I recall from one of your pictures, the prop was just touching the cowl without the adapter plate. Is that correct? If so, I would consider recutting the holes you already cut to move the cowl back to the windscreen, and cutting the lip to clear the starter. I have a feeling it would actually be a pretty cool look.
Then, assuming the holes you already cut are NOT compound curves, patch over the excess hole. I've done this in the past by taking a flat piece of material (aluminum, sheet plastic, anything that's not porous and thin enough to be flexible), and taping it down over the outside. Apply fiberglass, resin and cloth to the inside of the cowl, overlapping the existing material (or existing hole) by an inch or so. Once it ru==cures, trim the hole back to size and sand the outside, which should already be mostly smooth. The trouble spots will be the edges where the old fiberglass meets the new. If you work the resin in on application, you shouldn't have any bubbles in the fiberglass to deal with. You can finish it by skimming with Bondo or another filler material.
Prime and paint, and call it done.
(On a side note, might it be worth holding off on cowl fitment until you've completed the covering, etc, and done a weight and balance? Depending on where you end up, the engine might need to move, or other adjustments might need to be made that may once again affect the cowl fitment. Just a thought.)
Pretty much committed now to the new windscreen. I could only get a 4'x4' sheet locally (at a reasonable price) so it is about 5" short of reaching the rear L-angle mount on top of the cabin. The fit up forward looks very good.
I just came in from laminating up the starboard cowl cheek extension and did a test of super-gluing an edge-to edge polycarbonate joint. It was quite strong but I will probably add a 0.16" aluminum strip for additional strength (possibly strips inside and out). Bad picture ... ceiling light reflection ...
I actually like the look. The rake of the windshield looks more laid back, more streamlined. That was one of my pet peaves about some of the kits that have regular windscreens, is that they were almost vertical. The Badlands aren't bad but still more than I would care to have. I like that raked back look.
Todd
PS> Funny my spell/grammar checker found the first windscreen and said "British Word" and changed it to windshield, but it didn't care about it when I used windscreens. I guess the Brit's don't use the word plurals.
I have to agree with Todd - the rake looks good. My kit came with the material and a pattern printed on it, and I had to cut my own windscreen. It gave a few options in terms of the rake (how wide you fanned out the edges of the windshield itself). I cut the inside track and regretted it after the fact. Yours is going to look fantastic when complete, I have a feeling.
Question about the top where the front of the wings connect. If I remember correctly, there was mention about leaving a little clearance for the wing to clear the top edges of the windshield. I see on Kitfox's and other folding wing aircraft a rubber type seal between the wing and windshield edge. Is there something like that on the Badland? Or is it an open gap?
(1) I measured the circumferential length of the mating curve of the bubble cowling. It was 40". So the "pattern distance" of the widest portion of the polycarbonate had to match this length. That length is measured directly from the bottom of the straight portion of the screen that fits into the "trailing edge" channel mounts on either side. I'll do a diagram later today.
(2) if I understand the windscreen-front spar cut-outs question correctly, there is nothing in that area but the gap created by raising the butt rib to provide clearance for the root rib in folding/unfolding. I do have some leftover rubber edging material that I hope to use on the "flailing edge" channel. I will try and get a picture of that later today also.
Still no word on my Fokker Red Oratex. My color scheme is Sky Blue fuselage, major wings, vertical stabilizer & rudder. The flaperons, wing leading edge, and horizontal stabilizer are red. Chris says he has the blue and some PDF files with materials patterns for the various components. Looking forward to that.
Still a lot of cosmetic work on tidying-up the engine protrusions holes in the cowling.
Here's the windscreen-front spar mating. The cut-out allows access to the AN5 spar pin for folding. (Note the top portion of the windscreen has not yet been screwed to the butt rib.
Here's the u-channel weather stripping I hope to use on the trailing-edge channel. I have some similar material, albeit smaller, that I may use on the inside edges. This should remedy the sharp edges scraping against the polycarbonate.
I also plan to run a length of anti-shafe tape on the inside of the cowling curve so that the rough fiberglass does not scratch against the bottom of the wind screen.
The sides of the windshield are looking good and I like your idea on rubber on the inside and outside. If I understand correctly this makes a rubber channel or guide for where the wing slips into position. Good protection for all the components. Also good to hear Chris is getting together patterns to make the material cuts easier.
