The Mad Dash begins...

[mikeschn]

Gary,

The WW is on the back burner while I do some more experimenting with different foamie techniques.

The current profile is something I created with a spline, trying to minimize the amount of sharp bends. Once I glue on the tails, I'll show you the profile.

Oh, btw, here are the tails...



Mike...

[RAYVILLIAN]

Mike
after I said that I hit me that you've got another 2 to 3 feet behind the wheels so it won't have a flat back end.

Gary

[mikeschn]

Whew! I got those hard edges cut. Now I'm too tired to glue them to the foam.

But I promised you guys a picture, so here it is. I took the foam outside, and set the hard edges in place. You get the idea.



Mike...

[KCStudly]

Nice.

That's one of the things I wish I had done from the beginning. Should have included a hard edge along the full profile. I don't think it is 100/ct necessary, but would go a long way to avoiding damages and easier to hold the profile during construction.

[Fred Trout]

What is your hard edge made of ?

[mikeschn]

Fred,

That's 1/2" sandy ply from HD. I don't think it's moisture resistant, so I am relying on the protective properties of of canvas and epoxy paint.

@KC, it gets better. I will be attaching the spars directly to the hard edges. The notches in the foam are strictly for locating the spars!

Mike...

[Fred Trout]

Thanks Mike.

Very clever design married with your mad skills router table. I assume the 1/2 ply is inlaid into the rabbits you cut in the foam & does not stick out proud ? You could always pentrating seal the plywood with "the mix" before you cover with canvas - I would. When I did that, no trouble with TB II sticking at all although I did sand it and the foam as well. No real choice since my foam edges were all crooked and needed fairing or even GS to fill gaps. Might slow down your build a day or so since you want to let the mix air out a bit. Don't think that would hurt much.

[mikeschn]

LOL Fred, I see you've figured it out...

Yep, the ply is inlaid, and the spars go into the notches like shown here:



and the foam goes on top of the spars!!!



Something similar (but different) happens on the bottom!

Mike...

[GPW]

Don't mean to be critical , but the love of epoxy paint has cost a few people their roofs .. (remember) It doesn't penetrate all the tubes , like the Mix does ...
We don't trust any wood in a trailer unless it's "treated' ... But then we're probably a bit more HUMID than you are ...

[mikeschn]

Oh, I am definitely going to use "the mix". I want to seal up the end grain before gluing it to the foam. I will also seal up the faces, since the glueup is going to be gg to foam, Also going to glue up the spars with gg, and reinforce it with a screw. Yea, I like double redundancy. Or is that triple redundancy after the canvas is glued on?

Mike...

[GPW]

just curious ... I can understand planned obsolescence ( don’t like it) But why can’t they make a sheet of plywood that doesn’t fall apart ? ... We can land on a comet , fly by Pluto , but can’t make a sheet of plywood that survives a little water..

[mikeschn]

Wouldn't that be coroplast?

[GPW]

Coroplast would be fine if it held a screw , and had some real strength ,glued easily , didn’t decompose in the Sun in 5 years ... Maybe a thicker wall material ..
OSB , (the waterproof kind) seems to be a better choice for some things trailer (although it is very HEAVY ) and cheaper too .. And not that cheap -arse stuff they make RV floors out of ... One whiff of moisture , it turns to oatmeal ... We found we could even save that “stuff” (G. Carlin) with the mix , it soaked in the mix like a sponge ... once saturated , wouldn’t take any more ....Done !!! Mix worked a treat keeping water out and oatmeal contained .. Figure if it can waterproof plain cardboard then what else ...

[todd432]

Mike have you thought of using pressure treated (PT) for the spars? Home Cheepo has 1 x pt or even 5/4 pt ripped down to size.
No rot worry .
I know they make PT plywood but it's not to flat so not so good for the hard edges but .... might work on the floor.

I too plan on using my CNC to cut foam and wood for my Tear. looks like the bit melted the foam.
When I cut plastic on mine I have to slow the bit way down, my router could not go slow enough.
Now I have a spindle and can slow the bit speed down to 5000 rpm and still have the torque.
If your router is variable speed try the slowest setting and see what happens ( may have to slow your feed as well?)

Todd

[mikeschn]

Glenn,

There's always tradeoffs... if you were a scientist and could invent the perfect material, what would it be?

just for fun, here's a couple of my thoughts...
no wood, all those capillaries are so destructive
foam, while nice and light, has no density to speak of
aluminum has a nice density, but gets heavy fast
what if we combine foam molecules with aluminum molecules?
oh wait, there's also plastic
home depot sells a shed that is strong, light and plastic, but it"s not glueable
what if you combine wood molecules with plastic molecucles?
how about aluminum molecules and plastic molecucles? okay, that's my pick!!! Lets call it aluplastic
I'll bet you like alufoam better!!!
Lets design a teardrop around this stuff!!!

Mike

Coroplast would be fine if it held a screw , and had some real strength ,glued easily , didn’t decompose in the Sun in 5 years ... Maybe a thicker wall material ..
OSB , (the waterproof kind) seems to be a better choice for some things trailer (although it is very HEAVY ) and cheaper too .. And not that cheap -arse stuff they make RV floors out of ... One whiff of moisture , it turns to oatmeal ... We found we could even save that “stuff” (G. Carlin) with the mix , it soaked in the mix like a sponge ... once saturated , wouldn’t take any more ....Done !!! Mix worked a treat keeping water out and oatmeal contained .. Figure if it can waterproof plain cardboard then what else ...