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  can some of you more experienced hide glue users  give us some idea of what might be clues if we have a bad batch ? since it is my undestanding it has a shelf life , when in crystals and after it is concoted ... jody

Jody my friend I don't think that there is a shelf life (beyond some very long period of time like perhaps decades) for HHG when in crystal form.  I have yet to read any where that there is a shelf life until you mix the stuff.

Once mixed I can only comment on how I have used it.  I mix with distilled water, keep refrigerated when not in use, and it easily lasts 5 weeks and probably twice that.

A sign of when it goes bad once mixed is mold and smell.....

Alain left a cup of it in a fridge, if I recall correctly, for something like 3 months and the smell nearly killed him (figuratively speaking).... and it grew mold too.

Jody...as long as the granules are stored in a cool dry place, I believe there is essentially no shelf life. I've used granules that I've had in my shop for 3+ years.

Once dissioved in distilled water, I refrigerate the mixture in a 1-2 oz bottle and use as needed. I have kept this for over 8 weeks in this manner. Additional material has been frozen in the same bottles but double wrapped in plastic freezer wrap to prevent freezer burn (dessication). I have done this for 12 + months and the material has performed successfully.

The only "bad" sign I see can be mold growth. I delay the invasion of mold by boiling my plastic bottles prior to filling. I believe that distilled water also helps to delay mold growth.

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JJ
Napa, CA
http://www.DonohueGuitars.com

EDIT...I meant, no shelf life expiration

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JJ
Napa, CA
http://www.DonohueGuitars.com

 o.k. thanks for replying  ....... Jody

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Air tight seals and granules will last pretty much for ever. When My grandmother died we went to my grandparents lake cabin to clean it up to get ready for sell. She had not been out to the cabin since I graduated high school in 1974 and this was in 2000. Anyway in the pantry was 3 boxes of King brand Gelatin a regional manufacturer of home canning products and a jello knock off. They when out of business in the early 70's some time so I guess these packages were boxed in the late 60s or very early 70s. Anyway my wife made up some jello from these to occupy the kids while we cleaned out the cabin and it was just fine after some 30 years. In granule state the only real problem keeping HHG and or gelatin is moisture and Oh yea!, maybe mice

When I HHG my top bracing using my Go-Bar deck, how long do I need to wait before I can remove the rods and take the top out of the deck?  With titebond I'd wait 45 min.

I'm finally getting the hang of using runny HHG instead of titebond.  The very very best thing I like about it is that after 15 seconds the braces never move again and I can move on to the next brace.  With LMI white or titebond this was a problem for me as the fiber rods do not apply a straight downward pressure.

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Rick Hubka
Chemainus BC Canada

2 hrs.

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Yes, 24 before stress, longer still if you can, but research long ago showed that there was no benefit to clamping past 2 hours. But it did show losses if unclamped before the 2hr mark.

When you say stress, is that more stress than would be created by forcing the top into a dome with straight fan braces, like in a classical?  Should they be left longer?  I guess you are doing the same, with a steel string though, just with curved braces with more beef than a fan brace.  I take it that's not enough stress to count.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Yes, that is stress, so if you spring them, leave then clamped longer.

Just leave any critical or stressed glue jobs for the end of the day and leave them clamped up overnight.   

When I teach my "instant mandolin" course, the whole schedule is dependent on glue ups and drying time.   

With fish glue i preferred to wait 12h as per bottle instructions, (even if it makes a great bond in less than 1h) just to make sure.

So I always clamped things mostly late at night.

It was quite important to schedule and organize the various, otherwise the wait would have driven me nuts :)

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Build log

Thanks, that'll probably save me some grief!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

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For a violin when you join the two piece top you don't even use a clamp.  The magic of hide glue is that it makes it's own clamp as it dries.

Yes, it seems the hide glue shrinks as it dries, thereby pulling the pieces together. You get the same effect with fish glue BTW, but not Titebond, which is why it does not work so well for these "rubbed joints". It is also important that the pieces fit really well together.

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Rian Gitar og Mandolin

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