Vac U Forming

[Mark]

I've almost finished my mold for my Hummingbird cowling. I wanted to know if it is possible to Vac form the mold myself using 0.5mm plastic sheet (which the supplier says is good for Vac forming) using a normal household vacum and oven.

I was going to pre-heat the mold a little as well to give the Vac process a little more time to take the shape. Call it a copy of an SG Eagle or whatever you want but I think the SG cowling looks great and haven't seen or thought of a better shape yet.

 

[rhomodel]

It can be done but it is better to use a 2-stage vacuum, first the household en second stage a pump build-in the vacuform machine.

But why don't you buy the SG-cowl instead of copying it?

Julius

 

[Mark]

Rhomodel,

I would be surprised if the SG cowl would fit. I want it to fit like it was made for the boat, that means a return edge that runs to the shape of the tub which is a bit curved. I may be a bit fussy but it looks good and doesn't take much work or money to make a mold that fits the hull exactly right.

 

[rhomodel]

As long as you do not have to much undercut with the masterpart you can vacuform it. Do not overheat the plastic as it will become brittle. warming the masterpart will help you as it allows more time. Be sure to make a good frame to suspend the plastic in, th e more it has the countour of the cowling ( with about a 1/4 inch margin at all sides each) the easier it will be.

Julius