This is Anne of All Trades and I’m back with the workshop renovation I’m completing this week. This project is sponsored by 3M and I am working in partnership with the 3M experts on this forum to complete my build. It’s time to tackle the windows on the other side of the shop but in a different way. The no-weld window frames with the sliding acrylic were a perfect option for the front of the workshop because I needed the ventilation but on the back of the shop sits a busy road and I don’t want those windows to open. I also wanted to add some privacy so I sanded down the acrylic that I would be using and asked the 3M engineers what the best way of attaching these to my workshop would be.
They got back to me and suggested that using 3MTM Scotch-WeldTM Polyurethane Reactive (PUR) Adhesive to attach the acrylic directly to the studs in the wall would be the best solution to my problem. I can then also use the PUR Adhesive to attach the trim for the windows on top of the acrylic. This will save me 1,000 headaches trying to drill and screw the acrylic to the studs as it’s such a brittle material and I didn’t want to risk damaging it.
The first task was the prepare both the applicator and the adhesive, which meant hooking up the applicator to an air compressor set to 80 PSI. Next, add the tube of adhesive and let it warm up for 45 minutes, take it out and let it sit for 60 seconds, remembering to wear gloves. After letting it sit, pierce the tip of the tube with a nail punch, attach the applicator tip, put it back in the applicator and ready to go.
There are a couple of questions I have for the 3M engineers:
- How long can I leave the adhesive after it has heated up before application?
- What is the setting time? The acrylic can be heavy and I’d like to know how long it needs to be pressed against the wooden frames before it is safe to leave it.
Thanks for the questions. Open time and set time are definitely important to know before you try to use any liquid adhesive.
Open time (also called “pot life”, “work life”, or “working time”) is the maximum time you have between dispensing an adhesive and sticking the substrates together. A longer open time allows you to dispense a longer bond line.
Setting time (also called “handling time” or “clamp time”) is defined as the time between attaching the parts and the bond being strong enough to handle. For a PUR, we use 5 psi strength as our benchmark.
3M™ Scotch-Weld™ PUR Adhesive TS230 has an open time of 4 minutes and a set time of 2 1/2 minutes. That means you have 4 minutes to dispense along the perimeter, and then you only have to hold the window in place for 2 1/2 minutes while it sets.