Recent Topics
OEM-Sized Filter Comparison
by dlundblad
4 minutes 41 seconds ago
How important is DRY air? How to get it.
by SumpChump
12 minutes 19 seconds ago
DIY and your vehicle warranty
by Volv04Life
19 minutes 12 seconds ago
Dorco enters the DE market
by opus1
22 minutes 26 seconds ago
Favorite place to buy bulk copper wire?
by Ed_Flecko
Today at 06:40 AM
Great Timing!
by The Critic
Today at 02:05 AM
Tesla P85D insane launch reactions
by Nick R
Today at 01:40 AM
Who Calculates/ How is MPG Calculated?
by Nick1994
Yesterday at 11:29 PM
5w20 or 0w20 in racing
by Camprunner
Yesterday at 10:12 PM
Motor oil sale at O'reilly and Costco
by dothedrew1202
Yesterday at 09:56 PM
Cracking Bathroom Paint - Calling Bob Vila Types
by SumpChump
Yesterday at 09:46 PM
MT shifting into reverse by accident?
by FirstNissan
Yesterday at 08:44 PM
Newest Members
OliveH5, leafblower, JacobH, ElGeneral, partsguy1
52654 Registered Users
Who's Online
100 registered (A_Harman, Andrei, anl0109, AandPDan, 2010_FX4, 4wheeldog, 11 invisible), 1257 Guests and 167 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
52654 Members
66 Forums
225736 Topics
3592128 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG
Topic Options
#3331803 - 04/02/14 09:38 PM Solvent welding advice needed
sipman Offline


Registered: 05/27/12
Posts: 11
Loc: philly
Hi,
I have a 83 vw rabbit that some of my trim pieces have cracked. I experimented with Solvent welding using PVC Cleaner. This cleaner is Acetone and M.E.K. It worked great! I used metal Duct tape to hold the two pieces together. The nice side of the trim has a leather like texture molded into the plastic. The solvent went through the crack, and it appears it dissolved some of the adhesive and redeposited it onto the plastic.
SO needless to say, the crack is still visible. Do you think if I used a hot glue, or perhaps silicone caulk, I could seal the nice side so that the solvent doesn't find the adhesive? Will the Acetone and M.E.K. dissolve the hot glue or the silicone?

Top
#3331840 - 04/02/14 10:19 PM Re: Solvent welding advice needed [Re: sipman]
JimPghPA Offline


Registered: 08/22/09
Posts: 2852
Loc: Pittsburgh,PA U.S.A.
To weld plastic with a solvent use THF.

To glue plastic use Loctite E-20HP or E-20NS. The NS stands for no sag, meaning it will not run. You will require the dispensing gun. You can get the epoxy and dispensing gun from McMaster-Carr.

To heat weld plastic use a hot welding set made for plastic.
_________________________
Boy will I be happy when ALL vehicles on public roads are autonomous.


JimPghPa


Top
#3331846 - 04/02/14 10:23 PM Re: Solvent welding advice needed [Re: sipman]
robshelton Offline


Registered: 07/10/09
Posts: 450
Loc: Winston-Salem, NC
I've had good luck using pvc/cpvc pipe cleaner and solvent weld cement. But you need to be sure and not get any that has a color on the label. Not purple, etc. Sometimes you will need to bond a small piece of flat plastic behind the break to help support it if the material is thin. That is if there is room for it.
_________________________
1993 Camry 2.2 AT 415k - How far will it go?
1999 F150 4.2
2000 Camry 2.2 AT

Top
#3331852 - 04/02/14 10:28 PM Re: Solvent welding advice needed [Re: sipman]
sipman Offline


Registered: 05/27/12
Posts: 11
Loc: philly
What would brand name for THF be? I like using stuff I can walk out a store with, vs having to start an account with.

Top
#3331860 - 04/02/14 10:43 PM Re: Solvent welding advice needed [Re: sipman]
JimPghPA Offline


Registered: 08/22/09
Posts: 2852
Loc: Pittsburgh,PA U.S.A.
THF is sold in big drums. Any decent plastic molding company will have it. It is hard to keep in small bottles because it evaporates way to easy. It also has very low surface tension so it is easy to spill. I got some from a local plastic factory that does vacuum molding. I was there to discuss a project and we got to talking about glues, they gave me a little bottle of it for free, but they first gave me a print out of the MSD for it. I did a test by using it to weld two pieces of plastic together and then put the plastic in a clear oil. Those pieces have been sitting in that clear jar of oil for about a year now and they are still well joined.

Other than getting THF from some plastic factory I don't know where to send you to get some. I did not see the drum but they said they buy it by the drum. Probably 55 gallons.
_________________________
Boy will I be happy when ALL vehicles on public roads are autonomous.


JimPghPa


Top
#3331861 - 04/02/14 10:45 PM Re: Solvent welding advice needed [Re: sipman]
JimPghPA Offline


Registered: 08/22/09
Posts: 2852
Loc: Pittsburgh,PA U.S.A.
BTW even with the cap on correctly, the small amount of THF I had managed to evaporate.
_________________________
Boy will I be happy when ALL vehicles on public roads are autonomous.


JimPghPa


Top