tonneau cover & fabrication thereof

[sidcharles]

anyone have a tried & true way of fabrication of a cockpit cover?

AMT '29 Ford. no windshield or factory seat to contend. roll bar will be body mounted aft of dzus snaps.

i'd like to cover the entire cockpit, and then cut out the section for the steering wheel & driver's shoulders/ head.

to add to the challenge, i'd like to remove it in one piece.

it's not a compound curve as i can see, just a curl with a separate piece to snap over the dashboard.

would acetone soften and not melt a sheet of .010 styrene?  i might use a couple of layers for stability holding its shape.

tissue w/ thinned matte medium or canopy adhesive or micro-clear?

vacuum form [ grrr - would require a male buck]

a pickup bed would be flat, so that would be much easier.

the curve is corkscrewing me into the pavement.

ideas?

thx

[mcs1056]

Perhaps fabric (or tissue paper) hardened with white glue diluted with water would work. I did this to replace the plastic sails on a ship I'm working. Came out OK. I've seen videos where folks use this method to make tarps & stuff. You could make a form out of anything (Play-Doh?) & use waxed paper or mold release. Then some Mr Surfacer to make things smooth. 

Just a thought, as I will be trying this for a convertible top boot in the near future.

EDIT: I know...its not tried & true.  

Edited Friday at 06:27 PM by mcs1056

[sidcharles]

yeah; but we're all about breaking new ground here. certainly worth a try.

[Ace-Garageguy]

I've done it several ways.

One way was starting with a tonneau from something else, and adding styrene strips, then filling the whole mess...

...glassing the underside for strength while handling it...

...then pulling a mold from that (similar work on a different model)...

...and laying up a fiberglass part in the mold.

Trimmed and righteous.

Edited Friday at 11:38 PM by Ace-Garageguy

[Ace-Garageguy]

Another method, starting from nothing.

Tonneau is mocked up in aluminum tape, then a mold is pulled from that, and a full fiberglass tonneau is laid up in the mold.

(Sorry...all the previous pix in the Jag thread disappeared years ago due to a forum glitch when I edited text, NOT a Photobucket problem).

The weave of the cloth shows through, above, but disappears with enough coats of high-build primer. Using a finer weave cloth can impart a very realistic texture, too (I was out of the really really fine stuff when I made this one).

Then just cut the hole where you want it.

This method gives you a tonneau that fits perfectly, has rolled edges like you'd get from a soft one that snaps on, and realistic fabric wrinkles and droop.

Pinheads, scale rivets, or very small beads of solder can be used for the snaps.

 

Edited Saturday at 12:05 AM by Ace-Garageguy

[sidcharles]

interesting. the resin does not attack the styrene?

i have some West System resin & hardener in the workshop. along with fiberglass cloth & even a tub of brown micro balloons.

we'll see what sunday brings.

 

thanks

 

s.e.

[Ace-Garageguy]

36 minutes ago, sidcharles said:

interesting. the resin does not attack the styrene?

i have some West System resin & hardener in the workshop. along with fiberglass cloth & even a tub of brown micro balloons.

we'll see what sunday brings.

 

thanks

 

s.e.

West System is epoxy and does NOT attack styrene.

If you want a source for the ultra fine aircraft cloth I use, let me know and I'll PM it.

EDIT: I used West System epoxy and white microballoon to build this backdated bare-metal version of Micky Thompson's Challenger 1 

Build thread here if you're interested.

 

Edited Saturday at 01:32 AM by Ace-Garageguy

[Straightliner59]

13 hours ago, sidcharles said:

tissue w/ thinned matte medium or canopy adhesive or micro-clear?

vacuum form [ grrr - would require a male buck]

That's what I'd use. Well, I like kitchen parchment and diluted white glue. I would put a wire framework together to sit atop the cockpit area, and use that to form the paper--you know, so it could drape over a support? Once it's dry, trim it and paint it, and don't glue it on. You should be able to figure a way to align it with the cockpit, simply--a couple of small tabs, or such.

Just for the record--all bucks are males!😂

[sidcharles]

oh, deer . . . 

[sidcharles]

6 hours ago, Ace-Garageguy said:

West System is epoxy and does NOT attack styrene.

If you want a source for the ultra fine aircraft cloth I use, let me know

Build thread here if you're interested.

 

looks like some good reading.

i got this thought yesterday that for an initial foray into this field, i will probably use a piece of worn handkerchief. it's only going to be about 2" square when trimmed {actual - not scale!] with a 1" square hole in the middle.

appreciate the offer; maybe i'll take you up on the next one. thanks

Edited Saturday at 08:01 AM by sidcharles

[stitchdup]

1 hour ago, sidcharles said:

looks like some good reading.

i got this thought yesterday that for an initial foray into this field, i will probably use a piece of worn handkerchief. it's only going to be about 2" square when trimmed {actual - not scale!] with a 1" square hole in the middle.

appreciate the offer; maybe i'll take you up on the next one. thanks

the hankerchiefs work great. if you soak them in pva and let it dry its much easier to work and will hold its shape on edges. it prevents the edges fraying too. this tarp is a hanky and pva

 

[Chris V]

How about covering the opening and surrounding area with cling film/Saran Wrap, and a cover it with a dried-out wet wipe soaked in either diluted acrylic clearcoat or wood glue thinned with water?

Or perhaps it’s better to tape the dried out wet wipe/tissue paper down and apply the setting solution?

[sidcharles]

since i don't want to compromise the body, i think my first step will be two layers [applied individually] of aluminum foil over the whole thing. i believe if the cover gets to be oversize, trimming once dry will be an easy task.

then [after foil] i'm such a fogey, and no compound curves in sight, i'll use waxed paper to isolate the foil from the resin. yes; i've decided to use it - cautiously - and the fabric layer is still being decided.

more as the saga unfolds . . . .