PAR

This is one of the newer acrylic LPU's on the market. It can go over epoxy directly, though the manufacture only suggests going over it's primers or a tie coat (naturally). It will work well over the System Three primer. Over regular or Silver Tip epoxy, provide a good tooth and make sure the epoxy is well cured (at least a week), so shrinkage doesn't cause issues. This particular paint has very good gloss retention, but isn't as tough as the more traditional solvent based LPU's. The advantage of a primer is you can smooth the surface and provide a good tie coat for the finish coats. If straight over epoxy, you have to smooth the epoxy and provide sufficent tooth, which is tough to do on a clear epoxy coating.

Using a brush to apply epoxy is not a very effective way, of laying down a uniformly even coating and it's pretty wasteful. Applying epoxy with a brush, even with the bristles cut down 50% (the only way they work reasonably well), usually just leaves a pool where the brush first hits and tapered streaks, of ever decreasing film thickness, in the direction of each stroke. Admittedly, there are occasions where only a brush will do, but for the most part, you don't need them very often.

The Mass air flow sensor is part of a series of monitoring devices, to optimize the air fuel charge in the cylinders. Technically, the MAF senses volume, not density, but other devices in concert with the MAF can offset altitude changes. The engine still has to work with a decreased air density, but at least it can regulate the air/fuel mixture to compensate as much as practical.

 

A turbo is a fine way to make a little engine produce bigger engine power, but the draw backs can be considerable. For the HP you're looking for, a turbo would be a great way to cook a little motor, that's trying to be bigger than it really is. With the exception of high output engines, where forced induction is desirable for some reason, normally aspirated engines are decidedly the better way to go.

 

If you expect high altitude use frequently, select a bigger engine and learn to throttle back when lower. It's a difficult set of conditions to ask of any engine, so you'll probably need to make a hard choice as to which way you go - convenience adjusting mixture settings or a more high tech approach with it's related costs and temperament. If you go the high tech route, it may be possible to have a button that re-maps the EMC, one setting for altitude, the other for sea level. This will mean some aftermarket devices or possible a swap out for the EMC for each situation. Check with the engine manufacture to see what's available for high altitude operation.

A good way to rough in the fair, is by making a big sanding board to fit on a sander/buffer. Make an 1/8" plywood the same size as a sheet of sand paper, rounding the corners so it does dig in. Glue a flush mount arbor to the back of it, then spray mount sand paper to it's face. This will knock down the high spots quickly, while bridging the lows effectively. If you dust the surface with a misting of primer first, the lows will be easy to identify. One by one, wipe the primer out with solvent and fill the lows with a fairing mix and knock these down with "whirlly gig" and you'll be close enough for long boards.

Yeah, we've had a warm winter down here. The low last light was 59. I haven't had the heat or A/C on except for a few hours in two months.

I use the belt sander and DA most of the time. I have several different belt sander, some home made. I use them to rough shape spars, grind a plank edge back to the pencil line, knock down drips, you name it, though again, it takes some practice to use it precisely. If you want to roll a plank seam for fabric, the belt sander work fast. I make my own belts too, which is a lot cheaper then buying them. A little super glue and precise cuts is all it takes. I've made a jig for the various lengths I use.

Yes, they make power long boards that can conform to surfaces, but they're not cheap and of dubious ability. Most of these tools are strictly professional use and takes a good bit of experience to master, as they can remove a lot more then you want, very quickly. I have a home made power long board, which is a 1/2" sheet sander body and a piece of 1/4" okoume plywood screwed to the bottom plate. It's set to inline sand and works well on large surfaces. I have different size plates I can screw on to suit the job, some shorter, some more flexible, etc.

One tool that also gets used a lot, is the buffer/grinder. It's like an angle grinder on steroids. They come in 7" and 9" or 10" sizes and can remove material very quickly. In the right hands, they can fair things up to a degree. Get a variable speed version so you have some options on different materials.