Talked to George Happ today and learned that the Matco A8 axel http://www.matcomfg.com/AXLEASSEMBLYA8-idv-2555-1.htmlwhich is 9" long is meant to be cut to length depending on the installation. So that's $150 that can be spent on something else. Now i can arrange a firm time to get the brackets welded on and the new gear installed!
Bungees and hardware just arrived. One step closer to having the brackets welded on and getting this girl on her new legs. Still have to save some pennies for the wheels, brakes and axels. I was hoping to use the axels i have but the link George Happ at Matco sent me were for 9" axels and the ones I have are 6.5-7". I'm also building a plywood deck for the trailer to mitigate some of the risk of the tailwheel jumping the track again and doing further damage to the plane.
it looks like you've got a hose support clamp holding the fairing over the springs? Any brands that are better than others? How did you mount that spinner over the cabane? I'm trying to come up with ideas how to fair my gear.
Also got the top half of the cowling marked and trimmed. I was actually surprised how well it fit after trimming.you can see the trim line on the bottom, between 1/4-3/8" on the aft end tapering to nothing at the front.
Next project started, fairing the outboard leading edge strut attachments. Living at 4500 Msl where the density altitude can go over 7000 in the summer and reading all the comments about how fairings help with climb rate i decided to start working on that as well. VG's are in the plans as well. That's the same white foam under the duct tape that i used on the cowl. It bends nicely when it's warm but cracks when it's cold. I'm going to use drywall mud and sand it smooth before i glass it.
This is the video. At about 4:40 he starts talking about fairing design and about 8:00 he shows how he bent the sheet metal to make his mold. I thought he layed up the fiberglass on the inside ( female mold) making the exterior surface of the part smooth but he used a male mold. A guy in my EAA chapter showed me how to use plastic sheet over the surface of the layup to make it nice and smooth. These techniques ought to reduce the amount of work considerably.
I'm looking for it in the Mike Arnold videos but he made his landing gear strut fairings by bending sheet metal into roughly the right shape but open enough he could lay the fiberglass up inside it and then he just riveted the trailing edge together. The smooth surface of the sheet metal meant he didn't have to do any surface finishing.
I finally split the cowling again. not shown was making fastener locations and using 3/4" lathe screws to hold the top to the bottom. Ive stripped out most of the mold and marked the flange for trimming. My prep and cleaning must not have been enough because about 6" of the flange peeled off with moderate pull. I'll have to re epoxy thathere you can see all the lathe screws holding the top and bottom together. I was smart enough to mark the camloc locations in the lower cowling so reattaching was fairly painless although at least one on the other side is in the wrong place, you can tell as the cowling wants to bulge out until the fastener is released then it sits down nice and flat. I made amistake making the mold. You can see the cowling drops below the bottom of the fuselage a couple inches. The stock cowling doesn't. I'm wondering if I'm going to blank my radiator and have to lower it. I was hoping to reduce drag with this cowling not increase it.you can see the cowling is definitely peaked on top, kinda like me. The flat parts either side of the peak are very flimsy so i think i'll build it up with dry micro for a better contour and then lay another layer of glass over that to stiffen it up.Not sure how visible it is but there's about 3/8" between the cowling and the top of the firewall. This happened because the white foam used to make the mold was 3/16" thick, so the camlocs are pulling the cowling tight to the side of the plane and so the middle is being pushed up aggravating the fact that the 3/16" foam that wrapped around the firewall also isn't there.Again not sure how easy this is to see but I pulled out all the lathe screws except the front one and let the cowling settle at the back end and it hangs down about 3/8" below the original parting line, so I'll trim it tapering from that 3/8" at the back to nothing at the front. Probably still have to do something to seal the firewall but at least it'll be a much smaller gap to seal paying more attention to little details while prepping and laying up the fiberglass would have saved me a lot of work right now fixing all the bubbles and other imperfections but all in all I guess it's not too bad for my first real foray into composites.
The problem is i have a KF1 and most 4 bangers are flat out too heavy as is the yamaha. I'm not interested in 200 horses I'd be happy with a more reliable 80 hp if i didn't have to worry as much about seizing the engine. The only reason I'm looking at the 100+ hp options is that's what a huge percentage of the sled market is.
Like i said quick and dirty, but yeah any idea to cut weight down is welcome. I know I started the thread talking about high power engines but since i have a KF1 and winning the stol drags is just a fun little exercise but not something I'm serious about, finding a good engine is. And it would be nice to have a lightweight alternative to the rotax 582 with maybe a little more power, that could use an adapter like the above to mount a rotax c gearbox. If i were to decide to convert a sled engine these are things i would look for: 1. Obviously lightweight 2. Large production run with good parts support 3. Known reliable engine that makes 100-120 hp, Hopefully doesn't have the seizing issues rotax has. 4. Not alot of electrical work to do on it, ie minimal sensor and ecu/ wire harness problems to deal with. I don't know much at all about snowmobiles so can any of you suggest a make/ model/ year sled that would fill the bill? Any other requirements to go on that list? It would be nice to come up with a package that some enterprising individual could sell in kit form or even create a conversion manual that could be bought. If i had the machining skills it would be tempting but i don't.
okay here's a quick and dirty concept. The red thing is the engine the grey thing is the bed mount plate and the purple thing is Psru mount plate. Ok guys shoot it full of holes, any reason this couldn't work?