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View Full Version : Newbie Newbie starting from square one with big project



SMichelsen
02-05-2009, 10:49 AM
Greetings,
I am a complete newbie at vacuforming, but I --believe-- that it may the best answer for my project. I have discussed this project at yahoo's casting group, and some folks there have steered me towards vacuforming. Here is what I am up against:

After years of looking for one, I have a large vinyl item, a "rear panel lining" for my classic car, a Honda 600 Coupe. Please see the links below for some pictures. It is about 10” x 45” x 6". I have no experience in vacuforming but am interested in reproducing this rare, thin, brittle item. I am concerned that the one I have won't survive long!

My idea is to make a one-sided mold (that would hold up under multiple uses), and then use vacuforming to create reproductions. Only one side needs to look good (with vinyl’s texture, shine and color) as the other side faces into the back wall of the car. From what I have read of vacuforming, my negative "buck" will be mostly female shaped, with the plastic being pulled into the cavity. Fortunately the item has two large holes at what would be the bottom of the negative. I am hesitant to drill additional holes; I hope that will not be necessary.

I would really appreciate some direction as to materials and techniques to use to make the mold and set up a vacuforming table, and how to not destroy the original in the process! Any input here is much appreciated.

Here is a question: Is it possible to use VINYL as the plastic to be heated and pulled? I have read of thermoplastics, ABS, etc, but I am concerned that vacuforming may not reproduce the texture of the original vinyl across the whole item, so using vinyl itself would certainly fix that! Then I could make a mold of the bottom of the original, which is smooth, yet has all the contours of the top, and vacuform the vinyl with the texture face up.

OR, is the original not really vinyl, but another plastic impressed with a vinyl texture? If that is the case, can one find "proper" vacuforming plastics with that texture in place?

Here is the item in question.
http://www.honda600coupe.com/photos/panel_lining_project/

Here is the car it goes into.
http://www.honda600coupe.com/

This is certainly NOT the project that most folks would want to start out with when learning vacuforming, but it's the project I have set myself to. If anyone thinks a different direction makes more sense I would love to hear of it.

Thanks much!

spektr
02-18-2009, 08:27 AM
I think, this is a poor idea. I thermoform parts and I see a fairly complex tool, a fairly large part and a parts run of a dozen parts at most. I really think that you would be better off doing this in fiberglass and having it covered with vinyl sheet afterwards. It would be simpler, and more cost efefective for you. I wouldn't put this on my machines with a low part run and the tuning a new tool requires. You might find a shop hungry enough to do it, but nobody I know would touch it........ You will never get this made on a home style machine using a shop vac................ Scott.

svenakela
02-21-2009, 05:29 AM
Of course it's possible to do it with vacuum, but it's far from cost effective and require a big table and a complex mold.
I agree with spektr, do it with fibreglass. Either recreate the shape with a wood/MDF mold or make a new mold directly on the original part with fibreglass and epoxi.

Cool car by the way! :)

High Seas
02-21-2009, 06:53 PM
I agree with the guys - Fiberglass and not thermoforming. Chances are Honda did the theirs under high pressure and had a textured mold and stamped them out in minutes -- or less.
I'd suggest you look at using vacuum assisted resin infusion. Better control of resin to matrix than an open layup-- and you get to use a vacuum! - if you want one of those anyway. Using a textured surface it is possible to imprint a finish in the resin.
Product wont be as fragile as plastic - chances are thats why the original broke anyway.
Not a cheap set up - but some nice results.
Cheers - Jim