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Okay guys, some help needed here. I have been using T-88 for four years, only had a couple of failures until about six months ago. In those cases I knew what I had done wrong, corrected and moved on. About six months back I started to have about 50% failure rate, assumed it was old epoxy, replaced with new but am still having problems. No matter what I do I experience failure. When I first started using T-88 to hold delrin in ebonite, I used to wait eight hours before working the stem, never had any problems. I have now moved the untouchable time up to 24 hours and am still having problems. I haven't changed my method of scoring at all. I score the delrin both horizontal and vertical, score the inside of the ebonite, mix the T-88 in equal amounts. Nothing I do has changed but I'm having way too many failures. I either need some help at figuring out what I'm doing wrong or a new epoxy brand. bob

I believe the resident epoxy expert is Mike Messer...

Hey Bob,
Sorry to hear about your troubles. Perhaps you just received a bad batch of product. Sounds to me like you've followed all the correct guidelines so it must be the epoxy. About a year ago I tested T-88 24 hour epoxy against the 5 minute and also against a generic brand and tried a little destructive testing to compare. There was no difference in the results. I could not pull any of the Delrin tenons loose; at least not in a sense that a pipe smoker would experience. I ended up just using the generic stuff and have never had any issues. Hope this helps and it was good to see you again at the Chicago Show!

Best Regards,
Kevin

Staff, I've only had T-88 fail on me once, my fault. I'm cheap and I new it was old and should have been replaced....live and learn. One thing I haven't done in a long time, is mix equal parts. This is a tip I picked up on their website. I use a little less of the hardener, yes you heard right. They offer up an explanation, been so long I don't remember what it was. Check it out:
http://www.systemthree.com/
Dan
Gabrieli Pipes

Bob,
I have found that inserting the Delrin, as the final process, works best.
If you work the ebonite, with the Delrin tenon in place, the heat softens the epoxy.
Try to do all your drilling and shaping and, as the last process, insert the delrin tenon.

Huh. I never considered, Bruce. I always drill and turn the ebonite prior to inserting the delrin - which is always drilled through. I've never had a problem, and I suppose that could be a reason. Heat will destroy epoxy in very short order - it's one of the reasons why I use a very heat resistant epoxy when mating metals that need to be sanded or shaped after the fact (when I don't silver solder).