New Glue Gun

I was watching the Home Repair channel and saw them using a hot glue gun for gluing 2x4 together. It was hot melt urethane. The benefit of it was the ease of use of a hot glue gun, but the strength of urethane glue. It had 3 types of glues that could be used, depending on set time 10sec, 30 sec, or

60 sec. I was wondering if anybody knew something about them and if they were good to use in our hobby. I thought it would be great for people that have a CA allergy, because of it's quick set time.
Reply to
Normen Strobel
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I wouldn't want to live in THAT house! No glue; CA, urethane, or epoxy; will hold unless it can bond with the material being glued; either mechanically or chemically. I'd give the same caution words I've learned from building many "Pacific Ring" ARFs. The hot melt glue sets too quickly to soak into the wood fibers enough to create a strong bond. It's like 5 minute epoxy. If it's used on smooth wood, it will pull apart under load. Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

Sounds like a product review is in order. mk

Reply to
mk

It's not just hot melt EVA adhesive or the like, it is a urethane compound that cures via atmospheric moisture once applied. In other words, it cross links after application through a latent mechanism activiated by moisture. I found the physical data on the manufacturer's website*, but I'm still hunting for the MSDS to determine what if any isocyanate content is present, since people with a propensity for allergic sensitization will want to watch very carefully for that.

(* I believe it is Hysol urethane hot melt or a competitor's analog - Hysol's three available grades match the quoted fixture times)

Mike D.

Reply to
M Dennett

I have a lot of experience (although 20 years ago) with industrial hot melt glues. We used polyamine hot glues to glue speaker cabinets together. If the cabinet is designed properly, this stuff was stronger than any other method we tried. You wouldn't use it in small hand-held guns though!. It was fed from a heated pot through heated hoses. You wore a thick heat-proof glove and leather jacket ro protect yourself from this stuff. It came out very thin ut held station until the parts were pushed together.

Reply to
Paul McIntosh

Good idea, you guys all chip in and buy me the gun, I'll build a plane with it and write a review. :)

Reply to
Normen Strobel

As many ribs as I have seen fall out of broken arf wings with hot melt on the rib and no sign of what it was attached to I think I'll pass.

Tomb

Reply to
Thomas Buehrer

All that proves is that the manufacturer was using a cheap poor quality glue combined with poor workmanship. Also they are probaby using a low heat cheap glue guns. There are hot gun glues and guns that are designed for industrial use that can produce a bonded wood joints that are not going to fall apart. The question is who make a reasonable priced glue gun and sticks capable of doing the job for modelers?

Bob Ruth AMA 720565

Reply to
BobAndVickey

Don't blame the glue for a piss-poor usage of it. Even CA can't make up for improper prep and use.

Reply to
Paul McIntosh

It's HEAVY and not as strong as CA or epoxy; ask any ARF flyer!

Reply to
Lyman Slack

Bingo!!!

I've seen as much improper use of CA as anything else.. I deal with it constantly at work. Proper selection of an adhesive, and proper use thereof to extract the benefits is an art and a science.

That said, it is understandable how negative impressions of the hot melt glue concept exist, since people's experience is typically with hardware store or craft store type glue guns with low cost EVA based thermoplastic adhesives. That's about all that's on the retail market.

Despite that, I can't understand why anyone would glue in wing ribs with a hot melt glue gun. It's a good way to use way too much of an adhesive not suited for the job. I don't even use CA for that except to tack parts bonded with aliphatic glue. The wing still goes together plenty fast.

Mike D.

Reply to
M Dennett

I have owned several ARFs and I have never seen hot melt glue in the wings. In the fuselage, yes! The main problem I have seen with wings is NO glue. The parts are just set in place and a few parts tacked to hold everything together until the sticky paper was applied.

Reply to
Paul McIntosh

ROFLOL!

Not disagreeing with you, but I recently acquired an ISC Sean Tucker bipe sort of ARC. The only evidence of glue I can find is where someone forgot to turn the gun off in the wing. There is a trace coming out of the spar assembly, but none visible anywhere else. I have added my own since I intend to put a larger engine on it and would rather the wings stay together. I guess I am too picky. . . .

Jim Branaum AMA 1428

Six_O'clock_High Target snipped-for-privacy@Guns.com

thermoplastic

Reply to
Six_O'Clock_High

When hot glue guns first became available to the general public, there was an article in one of the model magazines about what a good product this was. Many people tried it, and the models tended to fall apart. I don't know what specific type of glue was available at that time.

Reply to
John R. Agnew

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