 |
www.TK560.com
Vacuum Forming, Movie Prop, Sci-fi and GIjOE Forum
|
|
|
| View previous topic :: View next topic |
| Author |
Message |
mr2monster
Newbie
Joined: 05 May 2007
Posts: 22
|
 Posted: Fri May 11, 2007 7:25 pm Post subject: Here's a good question for all you veteran vacu-formers.... |
 |
|
I've got a great product idea that i want to make. It's going to require that the plastic panel that I'm wanting to vacuum form be quite a bit thicker than what I'm able to melt...
My question is this:
Is there a way to laminate pieces of plastic together so that I can create a thick panel?
Here's what I'm thinking. Let's say (for simplicities sake) that I'm going to make a skateboard out of plastic with a relatively complex curve structure (I know the obvious flaws of this, I'm just using it as an example). I would probably create a mold that produced the size/shape result i wanted for the underside of the board... then, I would take the mold and plastic off, trim it but not pull the plastic from the plug and then vacuum form another layer over the top thus giving me a slightly larger mold so that it stacked correctly. (As opposed to making 10 pulls and then trying to stack them later).
At this point I'm unsure of what would happen... would the plastic stick well to the last pull? Would it need an alternative form of lamination (fiberglass resin, epoxy, etc) between coats to make sure that it would ahere properly?
Basically... how do i do this?
_________________
making stuff is cool. |
|
| Back to top |
|
 |
jegner
Site Admin
Joined: 30 May 2003
Posts: 2144
Location: Texas, USA
|
| Posted: Fri May 11, 2007 8:52 pm Post subject: |
|
|
Good question. I never considered doing such a task.
research time. |
|
| Back to top |
|
|
drcrash
Guru
Joined: 04 Sep 2006
Posts: 705
Location: Austin, Texas
|
| Posted: Sat May 12, 2007 11:13 am Post subject: |
|
|
Another possibility, for some things, is to vacuum form an outer shell, or an inner shell if it's the inside that needs to be nice, and then reinforce it on the other side with laid-up fiberglass.
That's how some bathtubs and hot tubs are made.
The nice thing about doing it that way is that the layup of fiberglass can be pretty easy if it doesn't show and have to be pretty. You can selectively use more layers of fiberglass where it needs to be strong, and fewer (maybe none) where it needs less reinforcement. If it's a bit raggedy, and lumpy where layers overlap, and with some little bubbles rather than having a perfect gel coat layer, it doesn't matter.
_________________
Paul (a.k.a. Dr. Crash)
Tired of buying cheap plastic crap? Now you can make your own! www.VacuumFormerPlans.com |
|
| Back to top |
|
|
mr2monster
Newbie
Joined: 05 May 2007
Posts: 22
|
| Posted: Sat May 12, 2007 4:07 pm Post subject: |
|
|
hrm, well i thought of that except my idea needs to have both sides "finished"
I'm still working this out in my head. I haven't been able to find much on google that answers my question... maybe I'll just have to try it. Any info you found helpful Jim?
_________________
making stuff is cool. |
|
| Back to top |
|
|
drcrash
Guru
Joined: 04 Sep 2006
Posts: 705
Location: Austin, Texas
|
| Posted: Sat May 12, 2007 5:58 pm Post subject: |
|
|
| mr2monster wrote: | | hrm, well i thought of that except my idea needs to have both sides "finished" |
Sounds like you don't want to give away the idea itself, but can you tell us more about the structural and appearance/finish requirements?
I can vacuum form stuff out of 1/4" plastic that's strong enough to stand on, using my little homemade vacuum former with 2-stage plumbing.
But it sounds like you need something you can not only stand on but jump up and down on, like a skateboard.
One way to do that might be to laminate 2 or 3 vacuum-formed layers, in a funny way...
One of the problems with laminating thickish vacuum-formed stuff is that you need mating surfaces to fit. Given the funny slight distortions you get from thinning and maybe from shrinkage, an exact fit might be hard.
On the other hand, if each of the mating pieces is basically flat where they mate, and each is slightly flexible before mating them, there may be no problem.
For example, I'm considering making RC plane wings in 3 layers, where the upper and lower surfaces are vacuum formed, and you sandwich them around a corrugated middle layer, which effectively gives you ribs. The corrugations go from the top of the bottom panel to the bottom of the top panel and back.
Before gluing, each of these three pieces would be rather flexible, but after gluing they'd be way, way more rigid. (Essentially, each corrugation would be turned into a box beam along the short axis of the wing, and the upper and lower surfaces, once glued to the corrugated layer, would suddenly be a lot like an I-beam the long way.) That would let you finesse the fit issues by flexing the pieces until they fit together in the right shape, then let the glue set to make a rigid structure in that shape.
_________________
Paul (a.k.a. Dr. Crash)
Tired of buying cheap plastic crap? Now you can make your own! www.VacuumFormerPlans.com |
|
| Back to top |
|
|
Fredo
Master
Joined: 21 Mar 2007
Posts: 251
Location: Kingdom of Nye Area 51
|
| Posted: Sat May 12, 2007 6:22 pm Post subject: |
|
|
How about bag lamination after each pull. I don't know what glue you would use. There is a site that describes bag lamination and I think I got there from here but I don't remenber where or how. If anyone knows how to get there it would probably be Dr. Crash. He seems to know something about every thing, and I mean that in a good way......... Fredo
Last edited by Fredo on Sun May 13, 2007 8:44 am; edited 1 time in total |
|
| Back to top |
|
|
drcrash
Guru
Joined: 04 Sep 2006
Posts: 705
Location: Austin, Texas
|
| Posted: Sun May 13, 2007 8:21 am Post subject: |
|
|
| Fredo wrote: | | How about bag lamination after each pull. I don't know what glue you would use. There is a site that describes bag lamination and I think I got there from here but I don't remenber where or how. |
There's some instructions for making a vacuum bagging setup on joewoodworker.com; those seem to be the most-linked-to vacuum bagging plans.
There's also a really simple setup using a FoodSaver-type kitchen vacuum sealer over on rcgroups.com. Here's an article with videos showing how to do it: http://www.rcgroups.com/forums/showthread.php?t=411348
A Food Saver can handle things up to about 10 inches wide and any length. (The "bags" come in a roll, and the machine chops off and seals as long a bag as you need.)
Vacuum bagging is easiest to do for laminating flat or simply-curved stuff, or stuff where the curves are not compound in a complicated or tight way. (With a rubbery bag you can do funkier stuff; a Food Saver bag isn't rubbery enough.) People use it for putting veneers on furniture, laminating skateboard decks, and putting balsa sheeting and/or fiberglass skins on foam cores for surfboards and model planes. (Among other things. (It's also used for full-sized composite planes, and the occasional spaceship, too. I think Spaceship One's hull was mostly made that way.)
_________________
Paul (a.k.a. Dr. Crash)
Tired of buying cheap plastic crap? Now you can make your own! www.VacuumFormerPlans.com |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Log in to check your private messages
Log in
Register
