Hot Melt Glue for Glue Blocks - Yes or No

[Hermit]

We've been having a few discussions about methods of holding a workpiece on the lathe lately, so I thought I'd ask a question that's been on my mind for some time.

Is it really safe to use hot-melt glue for attaching a glue block to a workpiece?
I've seen a number of 'good' turners on YouTube doing it, and have been doing it myself a bit on small pieces, but am still worried that it's not really safe.

Any feedback is very welcome.

[dabbler]

Works okay for me. Only ever used it with balanced pieces though.

[Hermit]

Works okay for me. Only ever used it with balanced pieces though.

I should have said, I too only use it for well-balanced pieces. I'll be mounting my largest segmented piece to date in a few days, still only 6" diameter 4" deep, but wanted to ask this and get responses from as many as possible before I continue.

(I had one let go a few weeks ago during that period of constant rain. It was in the moist air for a week before turning. Re-glued when the weather dried up and didn't have another mishap, but I'm still wondering.)

I know we're all entitled to one fatal mistake, but don't want to make mine just yet. :D

[Jim Carroll]

No problem if done properly

Just have to leave an air gap so you get two mating surfaces

[Hermit]

No problem if done properly

Just have to leave an air gap so you get two mating surfaces

Thanks Jim. Do you mean a recess in the middle of the glue block, or to use only a ring of glue around the outer edge? I haven't been making a recess, just putting a ring of glue around the perimeter of the face. I do always drill a small hole through the centre though.

312631

I guess you mean a recess.

[Sturdee]

I use it when turning Corian pendants etc.

Four blobs of glue which allows the air to escape from the centre and when finished I use inject Metho with an old syringe on the hot melt glue to soften it, so it's easy to remove.

Peter.

[Hermit]

I use it when turning Corian pendants etc.

Four blobs of glue which allows the air to escape from the centre and when finished I use inject Metho with an old syringe on the hot melt glue to soften it, so it's easy to remove.

Peter.

The hole in mine would achieve the same, I guess, except it might be a bit small and block. (Left over from my wood screw when turning the tenon.)

I use metho too, a tip from , but I use a cotton bud. That's why I like hot-melt - it's the only good temporary gluing method that I know of. Might have to steal yet another of your ideas, too, a syringe sounds much better.

I'm feeling much more confident about hot-melt now after the replies from dabbler, Jim and yourself. I'll continue to use it.

[Jim Carroll]

You do a ring of glue but leave a gap so that the excess air can escape.

Also quick hands as the longer you tarry the glue will go of and not bond like it should

So make sure all is prepared before glueing.

In colder days warm up the 2 parts with a hot air gun or the wifes hair dryer , help to keep the glue a bit liquid before going of too quick in the winter months

Hot air gun also helps in removing the waste block

[jefferson]

Also try the metho trick to unglue the glue beforehand on a piece of test wood. Not all glues come apart with the metho treatment. The Bosch stuff works really well.

[Hermit]

You do a ring of glue but leave a gap so that the excess air can escape.

Also quick hands as the longer you tarry the glue will go of and not bond like it should

So make sure all is prepared before glueing.

In colder days warm up the 2 parts with a hot air gun or the wifes hair dryer , help to keep the glue a bit liquid before going of too quick in the winter months

Hot air gun also helps in removing the waste block

Thanks for that Jim. And I use my hair dryer. Forgot to lose the long hair at the end of the 70's. :D

[Hermit]

Also try the metho trick to unglue the glue beforehand on a piece of test wood. Not all glues come apart with the metho treatment. The Bosch stuff works really well.

A good tip Jefferson. Thanks for that.
I've been using the Stanley glue, which comes off fine with metho.
I also just bought some long sticks of a cheap unknown brand from eBay and it loosens OK with metho too. Just tested it. Yet to see how well it holds timber though.


Actually, this raises another question that's been on my mind - what grade of glue does everyone use - the 'Heavy Duty' stuff intended for woodworking, or just 'General Purpose' glue? (I've been using the GP.)

[turnerted]

Use it all the time,just mke sure your glue gun is good and hot and preheat the tennon in the microwave on high for 30 secs.The glue should be bubbling when it goes on the tennon.
Ted

[dabbler]

I've used cheap generic sticks for decades now, in all sorts of areas not just turning.

Temp, speed and avoiding air gaps are more important IMO. If the glue seems tacky - start again.

[Hermit]

Use it all the time, just make sure your glue gun is good and hot and preheat the tenon in the microwave on high for 30 secs. The glue should be bubbling when it goes on the tennon.
Ted

'Pre-cooking' the tenon sounds like a good tip Ted. I'll have to try it. :2tsup:
And getting the glue bubbling. Actually, I usually put the glue on the bottom of the workpiece after heating it with the HD, rather than the tenon, but I'll try your way on my next. :cool:
Also, is there any reason why the glue shouldn't be put on the tenon before it's put into the microwave?



I've used cheap generic sticks for decades now, in all sorts of areas not just turning.

Temp, speed and avoiding air gaps are more important IMO. If the glue seems tacky - start again.

Good one, thanks for the extra info dabbler. I'll continue to use the GP sticks - the 'Heavy Duty' ones are much more expensive and hard to find.I'm learning a lot from this thread. Glad I started it.


I can add a couple of tips for those reading this in the future too:

The first - don't use hot-melt glue on wet (green) wood - it won't hold well.
(I saw a Mike Waldt video a while ago where he tried it and the glue let go almost immediately.)

And when buying a glue gun, it's best to buy the type that take 11mm glue sticks, rather than the 7mm ones. They have a faster flow rate, allowing you to get the glue on much more quickly, before it begins to set.
I bought a 120W, 11mm Stanley, with a ceramic 'quick-heat' element. They're a bit lot more expensive than the cheapies off eBay, but worth every cent.

[KBs PensNmore]

If I'm doing a large turning, I use the heat gun to cover an area approx 100 mm dia. and also use the tailstock to help support unbalanced work.
Kryn

[Tim the Timber Turner]

Most problems are caused by not having the glue hot enough or letting it get cool down before bringing the surfaces together.

I don't use Jims method of using a circle as I find the glue cools too quickly.

I have turned hundreds of lidded boxes 100 mm diameter by 80mm high using the following method with only a couple of failures. Mostly on a really cold day when the glue gets a bit brittle.

I use 3 larger dobs of glue near the outer diameter and allow the glue to squeeze out a little.

The larger dobs mean the glue stays hotter longer and allow more time for position the glue block.

The squeeze out shows me where to position the bench chisel for removing, which I do with smart tap of a hammer.

300mm platters can be held the same way but using 4 or 5 dobs.

One tip is to make sure there is no dust on the surfaces as this will affect the performance of the glue.

My $0.02 worth.

Cheers
Tim:)

[Hermit]

Most problems are caused by not having the glue hot enough or letting it get cool down before bringing the surfaces together.

I don't use Jims method of using a circle as I find the glue cools too quickly.

I have turned hundreds of lidded boxes 100 mm diameter by 80mm high using the following method with only a couple of failures. Mostly on a really cold day when the glue gets a bit brittle.

I use 3 larger dobs of glue near the outer diameter and allow the glue to squeeze out a little.

The larger dobs mean the glue stays hotter longer and allow more time for position the glue block.

The squeeze out shows me where to position the bench chisel for removing, which I do with smart tap of a hammer.

300mm platters can be held the same way but using 4 or 5 dobs.

One tip is to make sure there is no dust on the surfaces as this will affect the performance of the glue.

My $0.02 worth.

Cheers
Tim:)

Thanks Tim. The only bit I'm wary of is the bench chisel. The very old, dry Tas Oak I've been working with lately chips and splinters easily. I like the metho + patience method. I dribble in the metho all around the edges continuously while putting slight upward pressure on the block. It soon lets go and does no damage to the surfaces. I've even done it with a finished (sanded) surface without leaving a mark anywhere and gone straight on to put on coats of finish.

[jefferson]

Whatever method of applying the glue you use, you really need to be ready to bring the tailstock up and centred BEFORE you apply the glue. That way, either method (circle or dobs) should work. If it's a little cold, I'll add some more hot melt on the outside of the joint. Never had a failure using that method. Did once with warm glue on a cold day but it was only a small box so no drama.

[Tim the Timber Turner]

I'm not saying you have to use a chisel.

That's what I do.

You should use whatever works for you.

I mean you could use red wine if it worked for you.

Personally I would consider that to be a waste, and would revert to my trusty bench chisel.

Cheers
Tim:)

[Mobyturns]

Other matter to consider is the longevity of the glue joint. In my experience in the tropics the Bostick brand is reasonably OK if you leave it for a few months but it can & does creep.

[Hermit]

Other matter to consider is the longevity of the glue joint. In my experience in the tropics the Bostick brand is reasonably OK if you leave it for a few months but it can & does creep.

Yep. I think that my one failure was due to a combination of leaving it glued too long, a few weeks, plus the huge change in humidity, from dry to super-wet weather. Luckily it came off at the beginning of turning, so it was easy to get rid of the ding.



I'm not saying you have to use a chisel.

That's what I do.

You should use whatever works for you.

I mean you could use red wine if it worked for you.

Personally I would consider that to be a waste, and would revert to my trusty bench chisel.

Cheers
Tim:)

Definitely won't be using red wine. :D

[dougturner]

Hermit, I have also used the hot melt glue for quite a few years, and haven't had any let go. (Having said that, I will be very careful tomorrow). I have on many occasions used hot melt in a bit different manner, in that when attaching the piece to be turned to the wooden face plate, instead of gluing up as a tenon, I have put the two wooden faces together dry, then brought up the tailstock and tightened it, then used the glue gun like a welder and laid a good fillet of hot glue completely around the joint. No problems with air being trapped, and dead set sure to get a good square joint between the piece and the wooden face plate.

Never use hot melt directly onto a steel face plate as it won't hold, but strangely, an aluminium face plate hot glued to wood does hold. You can recycle great aluminium face plates out of old VCR players. I have a couple of them, face plates I mean. To preheat the aluminium face plate, I use an old electric iron set on about medium, held in the vice with the sole plate up, and just drop the aluminium face plate onto it for a few minutes, then glue it to the piece to be turned while still hot. Seems to work for me. Have fun!!!! Doug. :U


We've been having a few discussions about methods of holding a workpiece on the lathe lately, so I thought I'd ask a question that's been on my mind for some time.

Is it really safe to use hot-melt glue for attaching a glue block to a workpiece?
I've seen a number of 'good' turners on YouTube doing it, and have been doing it myself a bit on small pieces, but am still worried that it's not really safe.

Any feedback is very welcome.[/QUOTE]

[Hermit]

Hermit, I have also used the hot melt glue for quite a few years, and haven't had any let go. (Having said that, I will be very careful tomorrow). I have on many occasions used hot melt in a bit different manner, in that when attaching the piece to be turned to the wooden face plate, instead of gluing up as a tenon, I have put the two wooden faces together dry, then brought up the tailstock and tightened it, then used the glue gun like a welder and laid a good fillet of hot glue completely around the joint. No problems with air being trapped, and dead set sure to get a good square joint between the piece and the wooden face plate.

Never use hot melt directly onto a steel face plate as it won't hold, but strangely, an aluminium face plate hot glued to wood does hold. You can recycle great aluminium face plates out of old VCR players. I have a couple of them, face plates I mean. To preheat the aluminium face plate, I use an old electric iron set on about medium, held in the vice with the sole plate up, and just drop the aluminium face plate onto it for a few minutes, then glue it to the piece to be turned while still hot. Seems to work for me. Have fun!!!! Doug. :U


We've been having a few discussions about methods of holding a workpiece on the lathe lately, so I thought I'd ask a question that's been on my mind for some time.

Is it really safe to use hot-melt glue for attaching a glue block to a workpiece?
I've seen a number of 'good' turners on YouTube doing it, and have been doing it myself a bit on small pieces, but am still worried that it's not really safe.

Any feedback is very welcome.[/QUOTE]

I've seen a few sugestions in the past about bringing the pieces together then just running a bead around the edge, but have been wary of trying it.

Regarding steel faceplates, I've seen a vid where they used one without a problem, but they first lay the faceplate on a stove element and got it nice and hot first. I'll stick to wood-to-wood, I think.

Like the tip about faceplates from VCRs, though.

[Rubidium]

My tips for this, mostly already said but whatever.

1. make sure you let your gun heat up fully.
2. pre-warm your surfaces if its really cold.
3. If gluing directly on the lathe, hold it on with your tailstock. otherwise clamp it.
4. Let the glue cool fully before you start turning.