Need a method for easy/reliable top/back removal

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David King
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Re: Need a method for easy/reliable top/back removal

Post by David King »

You might even want to try the blue 3M painter's tape, especially if you plan to leave the plates attached for more than a week or two. Real blue tape sticks extremely well but it won't dry out or harden or turn gummy the way traditional masking tape can and the residue to clean up will be minimal. The HD brand blue tape is a low tack version that just falls off of it's own accord, not recommended.
Chuck Tweedy
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Re: Need a method for easy/reliable top/back removal

Post by Chuck Tweedy »

thanks David. the blue tape i have now sucks.

General FYI - I tried my test pieces with a well sealed (shellac) rim and test plate glued down with Elmers. Popped off unbelievably easy. Elmers is pretty fantastically crappy glue.

Titebond on tape seems to be a good balance of "solid" and easily undone.
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Rick Milliken
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Re: Need a method for easy/reliable top/back removal

Post by Rick Milliken »

+ 1 for the hot hide glue.
I think one of the other posts mentioned using HHG and paper. That’s a great add on to the idea. We used to, in the dark ages before multi jawed chucks for lathes were common, glue bowl blanks on to waste and then fasten them to a faceplate. We just used kraft paper, a chunk of brown paper bag or something. When you remove the block from the turning, you essentially split the paper.

Again, similar to what you’re trying with the tape, the HHG is just SO much easier to deal with than CA or dried titebond.
Matthew Lau
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Re: Need a method for easy/reliable top/back removal

Post by Matthew Lau »

+2 for hot hide glue.

Chuck, you're a hell of a better builder than me.
However, I think you're overcomplicating things.
Just use hot hide glue...you can stick in in a baby food jar in a cheap mini crockpot.
https://www.amazon.com/Crock-Pot-SCCPLC ... 2827&psc=1

To get it off...get some boiling hot water and some thin paint spatulas.
Keep your spatula blades in the boiling water and slide them between the soundboard/back/side connection.

The glue should "slide" apart and separate with minimal structural damage.

I used to do this in the kitchen on the stove....will be doing it again when I move back to my old place in a month or two.
Chuck Tweedy
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Re: Need a method for easy/reliable top/back removal

Post by Chuck Tweedy »

ok - yea
i did the tape-one-surface-glue-to-the-other thing. that was a week ago for the top to the rims. been fussing with other stuff since then
prior to that i did a test fit with 2-sided masking/mount tape, and it is pretty obvious that i'm stupid and the eventual glue-up would not work, but i tried the glue-up anyway - to prove i'm an idiot.
with 2-sided tape, the top loosened from the rims in spots because there is some stress in spots (some more than others) and masking tape is designed to let go - duh!
so what is going to be different with tape and its adhesive on one side and glue on the other - NOTHING! the tape side is going to let go. whichofcourseitdid - proving i'm an idiot.

ah! but I'm not that dumb! instead of using Titebond which would foul one surface with a non reversible glue ... yes, instead i used fish glue. so now i have one side sized in a protein glue - ha HA!, and now i'm going to go back and use thinned hide glue which - if i were not an idiot - i would have done in the first place. :P

I DID LEARN SOMETHING and will pass that along here. IF you want to glue something to the outer surface of masking tape - Wipe it down with ethanol just prior to gluing. the ethanol activates the shiny glue backing, and the glue sticks like a mo-fo.
See my pic - you can see that the fish glue totally destroyed the top surface of the tape
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David King
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Re: Need a method for easy/reliable top/back removal

Post by David King »

So what you're saying is to wash down the back of the masking tape with wood alcohol before gluing it to anything with hide glue?
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Barry Daniels
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Re: Need a method for easy/reliable top/back removal

Post by Barry Daniels »

My masking tape recommendation was based on my experience using the old fashioned white masking tape. Not sure it makes a difference but it might be worth another experiment, eh?
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Chuck Tweedy
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Re: Need a method for easy/reliable top/back removal

Post by Chuck Tweedy »

David, first - i believe that "wood alcohol" refers to methanol - but yes. procedure:
Stick tape down, then wipe down the non-sticky (showing) side with denatured alcohol (ethanol), let it dry, and then glue whatever to it. You get a bond that is as good as the tape. I've tried with fish glue, and titebond - they both stick real-good.
2-sided tape is the obvious first choice, but this is convenient for when you need the "compliance" that glue gives you.
Barry, this is brand new 3M blue (recommended by Mr David up there) and its pretty good, but... The same thing would have happened with white tape.
although the rim i'm gluing to is very wide, its not like the tape is stuck to a full-width flat surface. in your experience with gluing braces down i'm, sure it works much better because the tape is flat and bonded full width to a spruce plate. if you were to "prime" the tape like i'm talking about above, it would REALLY stick. It would be difficult to get off cleanly without pulling up spruce.
i do go on...
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Chuck Tweedy
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Re: Need a method for easy/reliable top/back removal

Post by Chuck Tweedy »

I've re-attached the top with thinned hide glue - it's on there pretty good. Hope it's not too good.

Alan - I wanted to ask the rational that Joe Curtin used for sticking hide-sized surfaces together with CA. It seems that if you are going to separate the hide glue anyway, then why not just use hide glue? Does the CA make it easier to get in there?
I'm going to try it right now for the back - what the heck - I'm learning a lot with this set of experiments so its all good.
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Bob Gramann
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Re: Need a method for easy/reliable top/back removal

Post by Bob Gramann »

If the thinned hide glue doesn’t crack right off, wet it with alcohol. Once you get the crack started, it will crack off as fast as you can feed alcohol into the growing crack. I don’t know the chemistry of why it works, but it’s really satisfying feeling it happen.
Chuck Tweedy
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Re: Need a method for easy/reliable top/back removal

Post by Chuck Tweedy »

Hey Bob - thanks for the tip - I was trying t understand the rationale for using CA between hide glue surfaces. I thought perhaps the CA expedited the alcohol effect or ?? I don't know, let go at a low temperature from the protein bond.
I know I will find out sooner or later - this thing WILL be coming a part some time soon.
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