best plastic adhesive/filler?

sohr · 06-16-2004, 04:31 PM

I'm cutting my lilliput frame and the top half of a double-din stereo frame bezel to meld together to form a single frame for my LCD.

At first, I thought I would use bondo to cover over the seam, sand, and then paint. But based on a recent thread, I read that Bondo is not the best filler for use on plastic (such as the lilliput frame). I visisted a local FinishMaster and asked for some plastic repair putty, and they looked at me kinda strange.

Eventually, I walked out with small bottle of Fusor #114... but I'm still not sure this is the right product. What does everyone else use for the plastic filler/adhesive? And is there a large chain store that might carry these products?

Snootch · 06-16-2004, 06:01 PM

The Fusor stuff should be good for what you are trying to do, if you are applying it to the right kind of plastic. I think that there are different models of Fusor are for different types of plastic, just like the "Duramix" product. Look on the back of your trim piece, there should be a code stamped into the back as to what kind of plastic it is made of. "PE" would be Polyethelene, or "PP" would be Polypropolene, there are several types of plastic. make sure that the filler you picked up is for the right type of plastic. Link discussing it:
http://www.fbodyaudio.com/cgi-bin/ya...num=1087323117
View the 6th and 7th posts down.

sohr · 06-17-2004, 01:16 AM

Thanks Snootch...

One question I have is that at the store, they told me the Fusor adhesive was for cosmetic use only... not for structure. Does these mean it won't do a good job of holding my two pieces together?

I did a google search on plastic repair putty, and found this:

http://www.idigpig.com/index.jsp?pageid=1087449223398

This seems much easier to apply (the Fusor is more liquidy and must be mixed on a mixing board first), is cheaper ($25 versus $13), and sounds like it should be stronger. Have you used any repair putty like this in the past? How does it compare to the Fusor stuff?

dag · 06-17-2004, 06:28 AM

sohr, I'm in the same boat as you. I was thinking to lay down some epoxy on the seams, then apply a then coat of bondo over it to create that smooth look'n'feel, then paint it.

I made a first attempt at this with fiber glass resin, but it just cracked after being in the heat for some time...i could have used too much hardener in the mixture as well. Turns out that .5 inch (thick) of fiber glass resin is actually pretty weak. So now i'm thinking about that alternative. My only concern is if bondo will adhere to the epoxy very well...

Pokey · 06-17-2004, 08:32 AM

Fiberglass, Its your best friend

Snootch · 06-17-2004, 09:16 AM

Quote: Originally Posted by sohr

Thanks Snootch...

One question I have is that at the store, they told me the Fusor adhesive was for cosmetic use only... not for structure. Does these mean it won't do a good job of holding my two pieces together?

I did a google search on plastic repair putty, and found this:

http://www.idigpig.com/index.jsp?pageid=1087449223398

This seems much easier to apply (the Fusor is more liquidy and must be mixed on a mixing board first), is cheaper ($25 versus $13), and sounds like it should be stronger. Have you used any repair putty like this in the past? How does it compare to the Fusor stuff?

For cosmetic use only. Yep, that's what your'e doing. That just means don't try to epoxy any type of load-bearing piece that has a good amount of stress placed on it.

excerpt from the website: "Bonds to most rigid or semi-flexible household plastics including PVC, CPVC and ABS. " I don't see why that wouldn't work IF your dash piece was made from any of those types of plastics.

i haven't used any putty like that. The Fusor stuff seems to be the ticket, if it's compatible with your plastic.

Dag- Fiberglass resin by itself is pretty brittle, you have to use the fiber glass to make it strong. If your using an Epoxy resin (most fiberglass resins are polyester) you can use carbon fiber fabric instead of fiberglass, but epoxy resins and carbon fiber are $$$. Don't worry about the fiberglass resin adhering to the bondo, it will, I would be more worried about the bondo adhering to the plastic. It might look good now, but in several months with the interior of the car heating and cooling down, the different expansion rates of the two materials can cause cracking at the seam. I think it would be a whole lot better to just use a plastic epoxy that is compatible with the plastic the dash piece is made out of to begin with. Here are common plastic types and their codes:

Code Plastic
ABS Acrylonitrile Butadiene Styrene
ABC/PC Polymer alloy of above
PA Polyamide (nylon)
PBT Polybutylene Terephtalate (POCAN)
PC Polycarbonate
PE Polyethylene
PP Polypropylene
PP/EPDM Polypropylene/Ethylenediene Rubber
PUR Polyurethane (Not all PUR is weldable)
PVC Polyvinyl Chloride
GRP/SMC Glass Fibre Reinforced Plastic

sohr · 06-19-2004, 01:34 PM

Thanks, Snootch, for your hour help.

Here is my progress with the goo so far:

First pass with the plastic paste:

Second pass with the plastic paste:

After sanding:

I suppose aftert sanding and making sure everything is smooth, I need to prime it before painting, right? Are there any good techniques on priming? Or do you simply spray as evenly as possible, and let dry?

moltensilver · 06-19-2004, 06:44 PM

I have a good link for you about primering and painting.

http://www.carsound.com/cgi-bin/UBB_...=001140#000000

Pokey · 06-19-2004, 11:23 PM

Take your time, its tedious. But it will be worth it.

SuperDave01 · 06-20-2004, 09:47 PM

I used Bondo on ABS plastic, and I am started to see where the pieces are shifting apart. Nothing is cracked yet, but I'm sure I will have to redo the whole dash piece. Keep us posted on how well this stuff holds.

mykolJay · 06-22-2004, 10:54 AM

I'm about to use "Rigid Filler" from Dominion. I got it off one of the fabrication links hear. It was recommended by a guy named Time Basille from hzemall.com. He is supposedly some supper pro in the custom audio world. I'll tell you how it comes out next week when i get my lilliput. Supposedly a hell of lot better than bondo.

Snootch · 06-22-2004, 02:28 PM

Please, post pics when you are done with it. I've read the threads concerning it by Tim Ballie, and am interested on how well it works.