Originally Posted by RPOL68
Butyl ribbon is easier and less messy than urethane sealer that is used on later vehicles. I'll avoid the butyl vs urethand debate here.
This debate really bugs me.
It is no debate among professionals and AGSS ANSi Standards.
I have posted info on another ongoing post.
I was a Certified LOF Installer for 15 years back in the early 70's and 80's. Have kept up with it ever since.
All C3's used Thiokol or Urethane from there inception.
Here is the product data sheet from 3M.
It says it all.
It is to be used as a supplement with urethane. Shear strength of Window Weld butyl is 15 PSI shear strength of cured urethane is 550 PSI.
How much energy do you think your body has in a front end collision or roll going 70 MPH? It is as important as seat belts to keep your body in the car.
Tacky, solid sealers designed for use with structural urethane adhesive to bond automotive glass to the car
body in full cut installation procedures. It may be used for installing windshields, backlites and bond to
primed metal and glass. Compatible with urethane, polysulfide and butyl sealants.
Directions for Use
1. Remove all old sealant.
2. Prime bare metal with appropriate primer system (urethane primer if products used with a urethane
Clean glass with 3MTM 3. Glass Cleaner-P.N. 08968.
4. Position windshield or backlite on pinchweld.
5. Be certain sealer makes complete contact between glass and pinchweld.
6. Use hand pressure on glass to insure a good seal.
7. Back fill with liquid sealant.
8. Water test using a gentle spray of water on roof.
For installation of stationary glass when used as supplementary sealer/bonding material with urethane
Directions for Use
3M glass products are intended for use as part of the repair process outlined in service manuals provided
by automotive manufacturers. For detailed instructions by car model, refer to information available from
the automobile manufacturer.
3MTM Windo-WeldTM Ribbon Sealer is designed and intended for use as a replacement to original
equipment butyl installations or as a supplementary sealant when installing stationary glass with urethane
** 3MTM WINDO-WELDTM RIBBON SEALER IS NOT INTENDED FOR A WINDSHIELD OR
BACKGLASS WHERE OEM URETHANE WAS ORIGINALLY USED.
For urethane set glass, refer to
and follow 3M Auto Glass Replacement Urethane directions. In some urethane set applications, use of
this product may be appropriate as a supplementary sealant.