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dai sensei
17th February 2006, 11:17 PM
I have often read about using hot melt glue for mounting things in the lathe. I got some decent glue sticks and it works a treat. Trouble is, in the articles it just talks about "removing mount", but no detail on how.

I have turned the mount off, but is there a simple way to unglue them? A thin hot wire would work I assume, is that what is needed? Flame torch would also work, but heat would damage the final piece.

Thanks for any advise.

Cheers

Skew ChiDAMN!!
18th February 2006, 01:02 AM
Depending on how thin the timber is (and how wide an area the glue covers) a cheap hand-held hairdryer can do the trick.

ubeaut
18th February 2006, 01:58 AM
Stick it in the fridge or freezer and it will break apart a treat, no worries.

Cheers - Neil :)

dai sensei
18th February 2006, 08:25 AM
Thanks guys, new there had to be a simple way.

rsser
18th February 2006, 02:19 PM
Mallet.

Even simpler ;-}

(Oh OK, with this method you risk chipping out some of the surface.)

dai sensei
18th February 2006, 02:32 PM
Mallet.

Even simpler ;-}

(Oh OK, with this method you risk chipping out some of the surface.)

Haven't tried the hair dryer or fridge yet, but I have tried the hammer and block before and it didn't budge it:( . I am using a high quality glue, lower quality glues had a tendancy to release whilst in the lathe:eek: .

rsser
18th February 2006, 03:15 PM
Yeah, as the missus might say, it's all a matter of timing :D

soundman
18th February 2006, 10:15 PM
I saw some articles a few years ago about using dead video heads as the work carrier and more recently custom made aluminium pucks.

you make up a heating plate out of an old clothes iron

the aluminium mount is heated on the heating plate when mounting up and you get it off the same way.

havn't tried it or seen it for real but it seems to have promise.

cheers

Tikki
18th February 2006, 11:01 PM
Went to a woodies design workshop today, and one of the hints I picked up (when I wasn't nodding off :p ) was to put the hot glued item in the microwave for a few seconds.

Cheers
Tikki :)

MajorPanic
18th February 2006, 11:13 PM
I use thinners to melt the hot melt glue I use to mount blanks to templates for routing copies.
Works a treat & doesn't raise the grain ;) :D :D

Auld Bassoon
18th February 2006, 11:37 PM
Went to a woodies design workshop today, and one of the hints I picked up (when I wasn't nodding off :p ) was to put the hot glued item in the microwave for a few seconds.

Cheers
Tikki :)

HiYa Tikki! The design workshop was that enthralling then? :eek:

Tikki
19th February 2006, 12:33 AM
HiYa back Steve! :)

It was as boring as .... the instructors were woodturners who wouldn't know the first thing about intarsia :rolleyes: I really wanted to rush out and buy a lathe by the end of the day ... NOT! :p

Cheers
Tikki :)

CHJ
19th February 2006, 02:31 AM
I use pine offcutts with Hot Melt for work held on worm screw.
To remove I split the pine into slim pieces down the end grain (rest pine block on support) with a malet & chisel, most times you can break off the narrower pieces by hand.

Rough Country B
19th February 2006, 09:57 PM
Gidday

I was told and it worked O.K. for me, to use a very thin bit of copper wire and with the piece turning in the lathe hold the wire on the glue and friction heats it up and parts it like cutting warm butter with a hot chainsaw.

Bodgy
19th February 2006, 10:04 PM
Just bring your work down to my shed. The steel walls heat up in the PM sun and (this was my first go) all the brackets fall off the walls and the hooks (for the vac - connected to small hand tools with 25MM dust port) drop to the ground.

Hot melt glue, I feel, is only suitable for temporary holds whilst you apply the correct fastening.

My shed got to 42 degrees on New Years day!

Underdog
20th February 2006, 11:33 AM
Just a quick note here...

I occasionally work on an edgebander, and the hot melt glue when cooled is rather difficult to remove. A technician showed me that lacquer thinner will take it right off. So that's what I use when I'm cleaning the machine. Follow wheels, copy shoes, press rollers and glue nozzle get cleaned of excess glue each evening. Even the brush I use to clean it with gets dunked in the thinner to clean the globs out of the bristles.

It would be worth experimenting with.

Markw
20th February 2006, 01:32 PM
Some of you mentioned using a better quality of hot glue - this I could really use - could you post a brand and a where to get? (Sydney Region)

with thanks

dai sensei
20th February 2006, 07:31 PM
Some of you mentioned using a better quality of hot glue - this I could really use - could you post a brand and a where to get? (Sydney Region)

with thanks

I get mine here http://www.timbecon.com.au/productsearch/default.aspx?txtSearchBox=hot+melt+glue

Tikki & Major - I use mine for including finishing, so not keen in the microwave or thinners as it may affect the finish (usually wax).

Jack - I tired copper wire, but the only wire that fitted the gap was so thin it melted before the glue did. Still a good idea for thick gaps.

Bodgy - yes the shed gets hot up here too, but not enough to make this stuff give way.

Thanks to all those who posted.

rsser
21st February 2006, 03:42 PM
While we're on the topic of hotmelt, I have a query ...

I'm working on a piece of myrtle burl as a bowl. Started with it rough turned, when dry I returned the outside and continued without thinking, down to the foot (ie. no recess in it for remounting nor enough width in the foot itself for gripping and then cleaning it up later).

The foot is about 50mm in diameter. No room for putting in a recess now.

I'm wondering whether to hotmelt glue the foot to a carrier in order to turn the inside. Would it be strong enough to hold? The bowl is about 185mm in diameter.

I could alternatively turn a groove above the foot on the outside but that would mean returning the bowl bottom after doing the inside, mounted on Cole jaws, and I'm not confident about maintaining a good line on the outside profile if this option is followed.

What do you think?

dai sensei
21st February 2006, 07:11 PM
50mm foot maybe a bit small, but you could give it a try. Make sure you have the glue all over and very hot to ensure it sticks for the full area.

MajorPanic
21st February 2006, 08:07 PM
Tikki & Major - thinners - as it may affect the finish (usually wax).

dai,

Thinners is cheap a chips, WILL NOT affect the finish as HMG doesn't penetrate the surface very much. It also dries without any perceptible residue so no problems.

Here's a tip;

Suck it & see ;) :D :D :D

dai sensei
21st February 2006, 08:22 PM
tip; Suck it & see ;) :D :D :D

Good point, shall do.

CHJ
21st February 2006, 11:39 PM
...snip..
The foot is about 50mm in diameter. No room for putting in a recess now.

I'm wondering whether to hotmelt glue the foot to a carrier in order to turn the inside. Would it be strong enough to hold? The bowl is about 185mm in diameter.

I....snip...What do you think?

I regularly turn items up to 300mm dia (plates) and deeper stuff 150mm dia with a sacrificial piece of 50X25mm pine for the worm screw fixing.

The total area bonded with HMG is rarely more than your 50mm dia. so as has been said as long as it is whole area I would say you will be OK.

Make sure it is Hot so that joint thickness is as thin as possible and even.

On one project I saw where someone was trying to recover a damage goblet shape, they bonded two side strips of 20mm square stock between the base block and the outer top edge to reduce the chatter and stiffen the piece whilst they worked inside.

Cliff Rogers
21st February 2006, 11:52 PM
...rough turned, when dry I returned the outside and continued without thinking, down to the foot (ie. no recess in it for remounting nor enough width in the foot itself for gripping and then cleaning it up later)....What do you think?
Can you make a jam fit chuck from scrap to hold it from the bottom while you finish the top?

rsser
22nd February 2006, 06:29 PM
Thanks CHJ, the inside of the bottom of the foot is concave, so I guess I'd need a carefully matched carrier to ensure a thin glue layer.

And thanks Cliff. From the base the outside of the foot curves inwards so jamming ain't an option unless I change the shape, which I don't want to do. Will lose the nice line that I thoughtlessly turned while in the groove. But your suggestion reminds me that there's an unused set of Acetyl jaws sitting on the shelf ... might be an option.

CHJ
22nd February 2006, 08:34 PM
Thanks CHJ, the inside of the bottom of the foot is concave, so I guess I'd need a carefully matched carrier to ensure a thin glue layer.



Not too critical in that case rrser, as the glue edges will be thin, it's just a case of reducing the amount of flex in the adhesive. If it is too thick then even a small amount of flex gets magnified the further out from the fixing you are. Never had a problem when used on virgin turning but there may be enough when trying to rework to be significant, you are going to have to contend with the wood movement which is bad enough hence why I suggested additional supports, these may be helpful regardless of your prime holding method.

Remember I have only been at this 10 months or so but have used lots of HMG