Electric glue gun suitability

[Fordulike]

Could someone who has used one of these glue guns, tell me if the glue can be softened and removed, by reheating the set glue with a heat gun or hair dryer.

I'm replacing one of my hall sensors attached to a tiny pbc inside the motor.
The pbc and sensors are currently held in place with a resin that can be heated and removed quite easily.

I need to be able to fix the pcb back in place securely, but not so much that it cannot be removed again, in case of another hall sensor failure.

 

[Scimitar]

Could someone who has used one of these glue guns, tell me if the glue can be softened and removed, by reheating the set glue with a heat gun or hair dryer.


I'm replacing one of my hall sensors attached to a tiny pbc inside the motor.
The pbc and sensors are currently held in place with a resin that can be heated and removed quite easily.

I need to be able to fix the pcb back in place securely, but not so much that it cannot be removed again, in case of another hall sensor failure.

Yes, it can be softened and removed again. That's a generalisation - there are many types of glue in sticks, but the ones I've used, that's true for them. In fact, some of the ones I've used the glue was so useless it just cracked off later when it got a bit colder.
Problem with these general packs of gluesticks, you don't know what you're getting.

 

[Deleted member 4366]

Be careful about hot melt glue. It'll melt if your motor gets too hot, and anything that was held down with it will move. There's some tutorials about replacing halls on ES. I think they use epoxy.

 

[Fordulike]

Be careful about hot melt glue. It'll melt if your motor gets too hot, and anything that was held down with it will move. There's some tutorials about replacing halls on ES. I think they use epoxy.

I did wonder that, but wasn't sure how hot these guns melt the glue.
The only epoxy I've ever used is Araldite, and that's way too strong in my opinion.
Any suggestions on an epoxy product to use that I can buy in the UK?

Or is there a way of removing Araldite without resulting to brute strength?

 

[johnc461165]

I have used a soldering Iron to soften the glue with no problems plus the heat is localised. I would also try the Iron on epoxy not to melt it but use it to cut it away.

 

[neptune]

One thing to be aware of with hot glue is the waterproof issue. The glue I use, from Wickes, says on the packet that it is not suitable for use in damp/wet conditions. Having said that, I immersed a glued joint in water for 3 days as a test, and the joint held.

 

[Fordulike]

One thing to be aware of with hot glue is the waterproof issue. The glue I use, from Wickes, says on the packet that it is not suitable for use in damp/wet conditions. Having said that, I immersed a glued joint in water for 3 days as a test, and the joint held.

Luckily, waterproofing the area wont be an issue, it'll be more of a heat issue.
The pcb and sensors are likely to encounter large heat fluctuations.
I have no idea how hot, but the motor can get warm on the outside, so inside must be toasty.
I think things may hot up a little too much for the glue gun method, but epoxy might be overkill, especially if I've got to remove the sensors again at some stage.
With the immense range of adhesives out there, there must be something that is heat resistant, but doesn't require King Kong to remove the stuff.

 

[Deleted member 4366]

Instant Gasket is high temperature silicone sealant - should hold it in place. Get it from a car spares shop.

 

[Fordulike]

Instant Gasket is high temperature silicone sealant - should hold it in place. Get it from a car spares shop.

Will grab some of that and give it a go, cheers Dave

 

[Scimitar]

Will grab some of that and give it a go, cheers Dave

Get the non-acetic cure one, if you can. The ordinary stuff gives off acetic acid as it cures, and that attacks circuit boards, wires, joints.

 

[sdrio]

A normal glue gun, like the ones they sell in Homebase, doesn't get particularly hot.

I have a fairly crappy Stanley one, which I use all the time. I can get the melted glue on my fingers from the nozzle, and while it isn't exactly comfortable, it doesn't actually burn me. It's maybe a little hotter than melted candlewax.

It's definitely WAY cooler than melted solder.

I'm not recommending you do this . . . it does hurt . . .! I can't see it doing much damage to anything but the most sensitive components though.