2nd 100cc APS build

[Peter Jack]

"advanced tinkerer" ...................... Mike I think you've just come up with a term that fits most of us in many ways. Well done!!!!! 

Pete

[sofadriver]

Had one of those days where I did a whole lot of work but don't have a lot to show for it.

I got the left lower mid panel cut & mounted and put on my first pieces of foam. Man, does this stuff sand easy! Even hand sanding needs a light touch. I made a sanding pad from a 3x21" piece of 1/16" bender board and use 21" sanding belts. It seems to work great. This thing's going to be as round and smooth as Kim K's backside. (and about the same size )

It looked like room to work on the bottom of the belly pan was going to be a problem so I raised the bike 10" off the lift. I cut a triangle of plywood and bolted it on across the rear axle adjusting bolts at the proper height and set the front tire on a cinder block. Both tires are resting on the same straight 2x4 so I can check my clearance. Lots of room to play now!

[bones]

Hey Sofa
 How did you determine the the shape of the front of the fairing?
Gut feeling--- most of mine is done that way
I haven't been able to come up with a shape that looks like it would be good and be within the rules.

cheers    Bones

[sofadriver]

Bones, check page 6 of this thread

[sofadriver]

After a busy week, and a minor body design change just above the fork tree, I'm making progress. I've been experimenting (not intentionally) with glues to hold my foam blocks in place. Traditional brush-on contact cement in a can seems to work best. Since I can't mate the sides of the blocks perfectly to the wood ribs I've cut them back a little (notice the gaps) and will fill them with spray foam from a can. That will fill any gaps and firm everything up, too. I need to get the horizontal center section in place before I start doing any real shaping.
 
Speaking of shaping, I found that you can remove the ends from two cheapie Harbor Freight contour gauges ($4.95 ea.) and attach them together. That gives a full 10" gauge. Most of the more expensive 10" models only give a useable 8".  Very handy.

[donpearsall]

Mike, I tried many glues too and have decided that a hot glue gun with the low melting glue sticks works best. It hardens pretty fast so you can just hold a piece of foam in place for a few seconds and it holds OK. THEN fill in with the spray foam.
Don

[bones]

Hey Sofa
  When I asked about the shape I was meaning how you cut the fairing to give the correct clearences to meet the rules
   for the front wheel visability.
   I have thought of a few different ways to meet the rules but all have compromises
 
    I like the BMST rules best---   dustbin fairings are legal
   Have you seen Tom Mellor's triumph?
   
   The body is coming along nicely-- I can't wait to see it finished.

    cheers     Bones

[sofadriver]

Hey Sofa
  When I asked about the shape I was meaning how you cut the fairing to give the correct clearences to meet the rules
   for the front wheel visability.
   I have thought of a few different ways to meet the rules but all have compromises

Bones I'm going to forward an e-mail to you that may be of interest. Watch for it from "knuhcsm".


"progress pics"..............

The seating (laying?) area is done. Most of that flat surface won't be there when done but it's an easy way to get the body even with the frame. I plotted out the shape on particle board and attached it to the bottom of the top frame rails. Since the frame is all 1'' tube all I had to do was glue 1" foam insulation board on top of that and trim to shape. Everything's nice and level. Eeeeeezy-peezy. It's also easy to sand for the rounded corners. I've covered it all with aluminum duct tape since the resins like to eat that kind of foam. Before the glass goes on I'll cover the entire buck with aluminum tape. Fortunately, it's cheap.

2nd pic; with the middle section filled in I can actually start to see where this is going. I'm going to hold off on the final shaping until all the basic shapes are in place to assure everything looks right and flows together. I only have one chance to get it right.

[tauruck]

You're doing a great job.

It looks pro.

A word of advice, Epoxy resin doesn't eat any kind of foam.
Polyesters have Styrene which eats stuff.

All in all, that is a really neat piece and looks right.
For someone tackling what is not your day job I applaud you.

[sofadriver]

Thanks. I know it would be stronger and lighter with epoxy but then I couldn't use mat. I'm not skilled enough to use cloth over all these compound curves. All the light colored foam I'm using isn't eaten by epoxy but the pink 1" stuff is. Either way, I still have to cover it all with the alum. tape so it will release.

[sofadriver]

finally realized why this bike looks so familiar..........

https://www.youtube.com/watch?v=cXLPFqdLPKY

[tauruck]

I hear you and understand your sentiments.
Remember that you don't have to use cloth in one big piece.
You can cut manageable size pieces. Do a little test on the flat areas.
If you're worried about the ends unraveling/fraying just spray some
3M 77 adhesive along the cut line before.

If weight is the enemy then cloth/Epoxy is your friend.

From the photos your skill is way better than you think.
Trust me, I say you can do it.

Mike.

[sofadriver]

Got the right side belly shaped up today. I'll wait to get the other side shaped before I do the final sanding and alum. tape skin.
I guess I made a (bad) decision at some point not to use ribs to establish the bottom shape. I'm paying for it now.

[tauruck]

Mike, make a great investment in a plastic contour gauge.
Eastwood sells them.
Mine is a blue one but I don't see it on their site.
I bought it in 97.

If you're working with composites I don't care what you buy,
this tool will be the best by far.

It will change your life. Get the longest one if possible.

[sofadriver]

You're right. Ive got one. Dont think I could do this without it. I'd sure like to find one that was deeper, though.