![]() |
It's composite time...
and despite having literally read every post of every thread in the -10 forum in the last two years to get prepared for my build, I find sometimes there are more questions than answers. Until you actually hold the parts in your hands, it's not always clear what the answers and advice mean, or what the questions/difficulties were to begin with.
I did all the composite work on my 6A two decades ago, and I'm sure I did it "wrong" compared to best practices, but somehow I powered through and made something that worked well enough for me. I want to do my best this time. I can't put it off any longer, having run out of non-composite tasks I can do on the build for now :p Last night I pulled the cabin top out of the corner, brushed off the shop dust and cobwebs, and studied it in some detail, picking out scribe lines, cross-referencing the plans, looking at some VAF threads about how to scribe and cut and rout things to fit. Lots of heat but a disappointing amount of light and clarity -- seems like I'll have to jump in and figure most of this out as I go, hoping that having read the VAF archives will be like a med student taking gross anatomy: you won't possibly remember much of it, but you'll be a better builder for having been immersed in it at one time. The scribe lines are there on my specimen, which is a relief. They aren't very straight, and they disappear altogether in places, but I think I can eyeball it closely enough. When I settle on a way to do the door seals, I am hoping I'll have the beginnings of a clue how to trim the door opening. Some of the better threads are missing photo links that probably would have answered a lot of questions. I plan to buy a carbide perma-grit type blade at Lowe's aviation tonight for my 20v oscillating cutter tool, and have a HF pneumatic 3/8" belt sander for inside corners. Still lack a lot of good composite tools in the shop. That brings up a bigger question for the guru's like DanH: What shopping list would you recommend for a guy starting over with nothing in the way of composite tools and materials? I need to purchase some of everything I'm likely to want for the cabin, cowl, tips, pants and fairings. Resin, hardener, scales, cups, sticks, spreaders, fabric, peel-ply, cutters, mat, brushes, fillers and thickeners, release agents, foam, clay, sanding and shaping tools and supplies, personal protective equipment - the whole shebang. I'll figure out a way to get the order past the CFO, but I want to outfit the shop to the level of no-regrets from the outset of the composite phase. If this has been answered elsewhere, forgive my waste of our bandwidth - and shoot me the link :D |
Bill--- to start the shopping list, good dust masks is a must.
I really like the pizza cutter style rolling knife (no idea what the correct name is) for cutting the glass cloth. http://www.staples-3p.com/s7/is/imag..._sc7?$splssku$ Resin------West systems epoxy works, may not be the pinnacle of things in the epoxy world, but works just fine for our needs. Ditto for the proportioning pumps they sell. If you want to be really precise get the scale and measure that way. Get micro, flox, and cabosil. each one has a specific purpose, micro is a lightweight filler, and does virtually nothing to add strength to the matrix, and may even weaken it. It is a filler. Cabosil thickens the viscosity and makes the resin stay where you put it. Flox makes the matrix strong. You can mix the various stuff together, to get the needed properties for what you are attempting at the moment. Spend the extra $$ for quality sandpaper. Get lots of throw away mixing containers, paper ice cream dishes work well, wider is better than deeper IMHO. Also lots of throw away stir sticks ----- I really like the bamboo paint stirring sticks some paint stores have---you can cut them in half to get a workable size. Popsicle sticks break too easy -------specially when mixing dry micro etc. Get lots of throw away cheap 1" paint brushes to. Sometimes you will need to cut the bristles down by 2/3 or so, this makes the brush good for stippling. When doing the big layup at the base of the windshield consider adding black tint to the resin-------will make the inside look much better when you are in the plane. Good luck. |
Quote:
|
Since you brought it up
Mike, what is the quality sandpaper and where's the best place to get it?
I plan to treat myself to a few perma-grit sanding blocks, but OTOH not going to buy one of everything at that store. |
Thanks!
I will check the local WalMart for rotary cutters. Maybe they will have the mat, too.
|
Quote:
Unlike yourself, this is my first build, and with no composite experience at all, I was very intimidated when I got to the glass/cabin top stage. I'm actually enjoying this stage for the most part. It is true, as I've read before, that this is where there is just as much thinking, planning, and researching as building - at least in my case. Between the scribe lines, on/off of fitting the top, bonding/trimming the doors, finishing the cabin top interior, door seals, door handles, door safety latches, etc, there is a lot going on! Mike's list pretty much hits what I currently own to a T - some West 105 and 205/206, their pumps, some cabo/flox/micro from A.S., a bit of uni and bid, shears and a pizza cutter, and plenty of gloves, stir sticks, and cups. I also bought a bunch of damaged dacron covering from AS to use for peel ply. I will repeat what he said about the widest, shallowest cup you can find. The ones I bought are a bit narrow and deep which tends to make a larger batch exotherm too quickly. It really doesn't take much to be able to continue/progress through the -10 glass stage. I continue to get tips here and from others' build logs, and, of course, I have some DanH threads book marked for periodic review. This one is one of my favs - http://www.vansairforce.com/communit...ad.php?t=44856 |
Aircraft Spruce
Aircraft Spruce will have all the stuff you will need.
Safety Equipment: Butyl Rubber Gloves (with cotton liners)Mixing equipment Gram scale (buy that somewhere else)Surface Preparation Aluminum Oxide sandpaper in 36 and 80 gritApplication equipment Pizza cutterI can't speak to the type of epoxy that Vans recommends, but whatever you use needs to be stored near room temperature along with the cloth. Epoxy usually has a one-year expiration so don't buy too much at one time. You will need a clean area to store and cut the glass cloth. |
pick up a couple boxes of gloves, 5 mil seemed to work well for me, the blue ones.
|
Home Depot sells acetone by the gallon.
Dollar store has 3 packs of paint brushes, and packs of paper cups (without wax!!!). Harbor Freight has 3 packs of paint brushes cheap also. Basically one time use. Used a variable temp heat gun quite a bit. Amazon has some good ones for cheap. A 5" orbital sander was indispensable for me. Bosch was my choice. 120-360 grit paper. As said before, the better ones you can find. Home Depot. +1 for the rotary cutter wheel. Spruce for a nice one, or Walmart or craft store for a plastic one. Get an extra wheel too. A burr on the wheel will drive you crazy when you make a nice cut and it misses occasional fibers😡. A good straight edge for cutting cloth. Aluminum yard stick works well so you have measurements also. A pack of silicone?? mini putty blades, or squeegee. Harbor freight has some yellow ones that work well, and cheap. West Systems worked well for me. The "calibrated" pumps got the job done. Repurpose all your worn out good drill bits for fiberglass. Face mask, and gloves were mentioned. I'll add, arm protection also. Wash as needed to keep the inside clean. As little exposure of the dust on your skin the better. The body can build up reactions to the glass dust from repeated exposure. |
On the door and window scribe lines, it is critical to verify the measurements before cutting. Personally, I would recommend re-drawing those lines based on the flange dimensions given in the plans. My scribe lines were off and I'm going to have to invest some time to re-trim some areas and scarf in more material in others.
I'd have saved a lot of time by investing the 15 minutes to draw the lines myself. |
| All times are GMT -6. The time now is 05:53 AM. |