ConcoursMustang Forums

Restoring - General discussions that span across many different groups of years and models => Processes, Products & Techniques => Topic started by: Paperback Writer on April 06, 2014, 06:00:15 PM

Title: Gluing Plastic Pieces
Post by: Paperback Writer on April 06, 2014, 06:00:15 PM
One of my '67 Deluxe Seat moldings was broken, and I've been having a very hard time gluing it back together.  Over the past few months, I've tried a couple of different "super glues" and some JB Weld, but the piece still keeps snapping in two...

Any suggestions on the best adhesives and techniques for gluing these type of plastics together would be most appreciated!

Thanks!!
Title: Re: Gluing Plastic Pieces
Post by: jwc66k on April 06, 2014, 07:07:25 PM
About that same time period, a chemical called a mold release was included in the raw plastic material. It made the molding process easier and cheaper. As a result no "normal" glue will work to make repairs. I had a similar problem with a 69 Fastback rear quarter window trim piece many years back. I went to a local plastics store, TAP Plastics http://www.tapplastics.com/ The guy behind the counter knew exactly what the problem was and said - "Use This." They are a West Coast operation and if you don't have a similar type of store, you will have to contact them to find out what "This" is and place an order.
Jim
Title: Re: Gluing Plastic Pieces
Post by: Paperback Writer on April 07, 2014, 07:06:22 PM
Thanks Jim,

It just so happens that one of the two TAP Plastics stores in Oregon is about 5 miles from my house - so I'll definitely have to pay them a visit this week!
Title: Re: Gluing Plastic Pieces
Post by: 67gtasanjose on April 07, 2014, 07:39:05 PM
I used a product called PLASTEX. Used it on the console and deluxe seat backs. I  bought it on the Bay. It works very well on this plastic and and is MOLDABLE! They include a molding bar that can be heated up to form even missing parts of the item being fixed. Here is a video (including info-mercial) that demonstrates how to use it.
http://www.youtube.com/watch?v=oZHP6fE-BNU
Title: Re: Gluing Plastic Pieces
Post by: 1967 eight barrel on April 08, 2015, 10:07:18 AM
Mold release has nothing to do with those plasti-glass parts. They are not plastic in the traditional sense. Permatex Perma-poxy worked outstanding on the interior quarter trim and a to make up missing edges on my '67 deluxe seat backs. Make sure you clean parts throughly, use some sandpaper on the inside of the trim. You'll want to leave a little extra for reinforcement. Part number 84115.  It's about 5.50.
Title: Re: Gluing Plastic Pieces
Post by: 1967 eight barrel on April 08, 2015, 10:11:40 AM
 I tried the same product. It didn't bond well. I did use the moldable block with the Permatex product. I pulled the grain of the seat onto the block and used the Permatex 84115. Absolutely perfect results and the bond was permanent.
Title: Re: Gluing Plastic Pieces
Post by: Bossbill on October 31, 2018, 08:48:55 PM
I'm also replacing pulled through and totally missing sections of the side seat plastic.
I'm using Devcon plastic welder (actually an epoxy) which goes for around $7 a twin tube. You don't get a lot, but it works.

(https://cdn-tp3.mozu.com/24645-37138/cms/37138/files/6b33ef36-6803-4fe2-a00a-efe1181732ed?quality=50&_mzcb=_1541009222975)

This stuff actually sticks to plastic! While rebuilding where the deluxe seat side plastic attaches to the rear of the seat frame I've drilled and sanded on this stuff and it hasn't come loose. I'm building it up layer by layer with 100 grit in between coats.

When the midsection screw pulled through it took with it the standoffs. By using a small section of heat shrink tubing I re-created the standoff and filled in the front to be ready for texture. Did the same with the rear section where a large chunk was missing.

The only step prior to what you see here was to create the basic shape with gaffers tape and spread in a layer of epoxy. The standoffs came next. Not near done, but thought you'd like to see this part.

[on edit]
This is some of the most potent smelling stuff around. It also appears to be a huffer's dream. I wear my paint mask when using it. It has almost no smell after it dries, unless you sand it, at which time a faint version of the smell returns.
Title: Re: Gluing Plastic Pieces
Post by: JKWilson on November 03, 2018, 11:59:54 AM
Agree with Bill 100% on this. The Devcon plastic welder is the way to go. I discovered this about 7 years ago and have done all of my plastic repairs with it. I had tried several other products prior but they failed, either immediately or eventually. It's usable across a broad range of plastic types too.