Vacuform Canopies - How do you make your bucks?

General Discussion General Modeling Discussion
1

I am looking for advice on making bucks for Vac Canopies.

I have a Micro Mark Vacuform machine that has been basically gathering dust since I bought it 8 or 8 years ago and I want to pull it out of moth balls. Any advice would be appreciated. Thanks.

2

I haven’t done it in some time, but when I did, I cut profiles, x-sections, and plan views from sheet styrene and assembled them to make a sort of “egg crate.” I then filled the spaces with Milliput and sanded everything to shape once the Milliput had cured. I then primed it and sanded it again, repeating it as necessary until it was smooth.

The old-fashioned alternative is to carve a master from balsa or basswood and apply several coats of sanding sealer, sanding between coats until satiny smooth.

3

Please excuse my ignorance, but what’s a “buck” in the context of vacuforming? I’ve never heard the term before. Is it the master, the form you use to shape the piece?

4

Baron, your assumption is correct.

To the OP, don’t use CA glue to seal wood bucks, as it will scorch when the hot plastic is pulled over it. I had that happen to me.

5

Note that the vac part will pick up the tiniest imperfections in the master, or “buck”.

I’ve never owned a vac form machine, just have done some plunge molding.

But for instance, if you are using a craked canopy as a master, the crack will show unless you sand it out.

Useful skill, show how it comes out.

Bill

6

Thanks, G! The context suggested it, but like I said, I’d never heard the term before.

To the question, I’ve used 2-part epoxy putty to make my masters, so far.

7

Hello!

For vacforming I found it fastest to make masters out of plaster of paris blocks (they sand pretty easily when still fresh) and then soak them with CA for hardness and final finish. Making them out of wood is also pretty fast and easy, too - it’s good to cut a few “gauges” out of cardboard to see if you got the final shape yet - a kind of approach inverse to what Space Ranger proposed. In case of wood you need to watch for grain - if you’re not careful with sanding it may show on the vacforms… One cool thing I found is to cover your master with a thin layer of liquid soap - do it one time and it takes care of separating the master from the formed canopy for many runs on.

Good luck with your canopies and have a nice day

Paweł

8

Sorry Baron, That’s a term I have heard used. I supposed I should have said master or template–or all three …

9

Thanks for all the ideas guys.

I guess I should have stated that I was looking for a method that utilizes and existing once-piece kit canopy. My idea was to press the kit canopy into a blob of 2-part silicone mold putty and fill the resulting mold with resin. The part that I remember giving me issues the one time I tried this was the bottom edge areas not being well defined.

Also, is using the existing canopy as master a viable option with a vac machine like the micro-mark version? I guess it would not be very smart, if you mess the thing up and did not get a good result…

10

I carve my patterns from basswood. I sand with increasing grits of sandpaper. At 600 grit, I spray clear lacquer over it, then a final sanding with 800 or 1000.

11

Oh, no need to apologize! I learned a new term! [;)]