A Customer with some older Tolex adhesive requested information on shelf life and how to tell if it is still good. Here are some thoughts on this:
While the rated shelf life of the Tolex glue is 1 year, realistically, it can often be used (if stored correctly) for longer time periods than that. Doing a test bond with some scrap material provides the answer we need. First, check if the adhesive is still in a uniform solution. If the adhesive is lumpy or inconsistent, the adhesive solids will not go correctly "back into solution" with agitation. Consequently, if the adhesive is separated or lumpy it is no longer usable. Second, if it is still consistent, the next step is to do the test bond. The fastest way to test is to use the traditional "two sided" adhesive method rather than the alternative Tolex single sided application method. Spread the adhesive on a test piece of Tolex and plywood (or MDF or particle board). Allow the water to flash off for 20-40 minutes until dry. Put the substrates together and smooth out. If you get good initial grab and the Tolex sticks well, then long term performance will be fine as well. If you find that you need to purchase more product instead, Antique Electronic Supply offers quart containers that may be a better size for you. 480-820-5411 is their number and www.tubesandmore.com is their web address.