It’s been a while since this was discussed. I’ve been scouring the cyberverse without much success and just wanted to see what the consensus is these days.
Is there a glue that hotwires reasonably well?
If not, what glues are you currently using for EPS? I remember someone posting a link to some blue stuff a long time ago that they liked.
I would like to get the ball rolling on another stringerless EPS board with the remainder of my block of 2 lb EPS. However, I’d prefer to have a simple glue-line to use for reference and would prefer to do it before hotwiring if possible.
foaming pu glue is real strong and sands great. add the glue to one side and a light mist of water to other and it’s expands deep into the eps (quite surprising actually)
… sorry don’t know how it goes with hot wire.
… I got some time, Back soon with hot wire test result (on scraps)
Gorilla Glue white or Roo Glue White. I would think that you could put a drop of pigment in it to make it more visible. My personal “Fav” is the Roo. It is a glue that was developed for laminates.
Yorky use the shellys version, the one pictured let’s go as it gets older and if you leave your board in the car in the heat. Had a few board glue ups delam with Sika but none with the shellys version.
There was a can of 3M #78 at work so I made a couple test pieces. They went through the hot fire fine. The adhesive takes longer to set than I expected, it needs several hours at room temperature. The can has an adjustable spray pattern. I can’t say it’s better than this or that but it did work. Quality of the cut on the edges being glued is more important with #78 than with foaming PU.
Out of curiosity, did you apply it to one surface or both (in the case of the 1.5 lb sample)? Did the pieces stick to each other aggressively or did it feel like you could reposition them at all before the adhesive set (say, in the case of lining up matched cut halves)?
NSB- I did each surface. The can says spray, wait 2-3 minutes, then bond-and gives a two-surface tack range from 2 to 15 minutes. I split one sample apart by accident later in the day and once I pushed it back together and waited a few more hours all was fine. Part of that day the samples were in a below-freezing car which probably extended the open time of the adhesive.
During tack time, can the freshly bonded surfaces be shifted for adjusting alignment while still in contact with one another?
Have you tried sanding the 3M 78 adhesive seam line? If so, how well did it sand? When I called 3M a while back, the customer service rep said, “Sure it can be sanded” – questionable wheter he really knew.
Have you tried using it for bonding foam to another surface like wood or cured resin/FG?
I have a can of the 3M 78. Waiting for the weather to warm up some before using it.
The second set of pieces I tried with 3M #78 were re-positionable up until about 15 minutes after application. I took a one foot by two inch section apart 10 or so times and it went back together, getting more difficult to separate as time progressed. It also seems to bond wood to EPS and sanded FR4 to EPS. It’ll be a day or so until I can try taking some tools to the samples.
Wire will burn right thru. But I don’t use a Hotwire for outlines etc. I don’t think there is a better glue for EPS than Roo glue. Made in Oregon of course.
