Vacuform Canopy bank- or sharing

[mldixon]

Originally Posted by CMDRTED

I would sand that baby butt smooth. any wrinkles or imperfections will show up on your plastic. Have you guys considered sculpey clay? I have molds I used 5 years back and still going strong. No mixing carves with xacto and sands with 400 grit down to 600 grit. Hardens in 15min at bakeing temperature, there is a down side..... You have to follow the directions on the package, not exactly Man friendly!!!

HMMMM? My experience is quite the oppisite. I use a lower vacuum setting and make the pull. I have not had any imperfections show at this point. I use this method because the plaster flows into the plastic mould and takes the shape quite nicely. The plaster is easy and quick to work with. It sands and repairs very nicely. The problem with the clay is that you have to build the shape up and become the sculpture, not that I am opposed to this, but I like to capture the shape that the designer makes and it goes pretty fast. But heck if we all did the same methods the world would get dull pretty quick

[rbeach84]

I believe the Sculpey only has much odor, if any, when over-cooked. I have used a two part epoxy for years that is made for taxidermists. Never tried the Steel Putty (steel reinforced? that would be hard on the files ) but it sounds promising.

Just about anything will work for a master, especially if you recast in another material (such as carving from balsa wood coated with CA, then casting a mold using P-of-P.) Just must be rigid, able to resist the vac forces and the heat.

Key to good quality canopies is a super-smooth surface on your plug and sufficient heat. If you can't get that with P-of-P right off, use coatings that allow for polishing. Waxing the plug doesn't hurt as long as it doesn't react with the plastic - which will be hot!

Fun part is experimenting with the basics until you get something that works for you.

[Zathros]

The Steel Putty has a really long ( long enough to make a nice looking cockpit glass mold) working time. It isn't hard on files at all. Machinist files are far harder. You just have to hit them with a fine brass brush to clean the file, but the steel epoxy files great.

[Zathros]

Originally Posted by mldixon

Issac
Here's how I make my plugs in plaster. Just thought I would share.

I don't think I would go the steel putty route for something that big. Maybe concrete? Or a strong balloon to take up most of the space and just put putty on the mold surface? It would dry out and you could then "pop" the balloon, maybe fill it with great stuff?

That is one big a$$ canopy!!

[mldixon]

Originally Posted by Zathros

I don't think I would go the steel putty route for something that big. Maybe concrete? Or a strong balloon to take up most of the space and just put putty on the mold surface? It would dry out and you could then "pop" the balloon, maybe fill it with great stuff?

That is one big a$$ canopy!!

Yes 1:16 scale is getting a little big at times, but I am still in love with it for the moment.

[Zathros]

What is it that you are making? If I may be so bold?

[mldixon]

Originally Posted by Zathros

What is it that you are making? If I may be so bold?

You know what I am making Corsair

[Isaac]

Can an ink jet printer print on clear transparency? Is that done so i does not stick to the plaster?

I just printed it on card and use it as the mold and then just tear it off and sand it.


Isaac

[mldixon]

Originally Posted by Isaac

Can an ink jet printer print on clear transparency? Is that done so i does not stick to the plaster?

I just printed it on card and use it as the mold and then just tear it off and sand it.


Isaac

Sure they make overhead transparency film for Inkjet printers.

I use the plastic because the paper soaks up the water from the plaster and sometimes this results in a collaspe of the mold. You should move to the wet sponge technique for final sanding and try to get the sponge on before the plaster is completely dry, that is why I included the clock times on the photos. Also when you use the plastic you can see the plaster and work out air gaps etc. I also did this in card at the start, but moved on to plastic as I progressed.

But I spend a lot of time outside of the box looking all the time at new materials and techniques.

[Isaac]

Here is the positive mold that I case with Plaster of Paris. I had to fill in some areas and smooth it to match. I used the Sqadron Thermaform clear plastic ( which is no longer sold ). Heat over a candle and "smash over the mold.


I was never really happy with this plastic since it was never truely clear.



Zathros, I really want to see your method. Please post some pictures.


Cheers

Isaac