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Using HHG for the first time
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Author:  Matthew Jenkins [ Tue Jul 27, 2010 5:39 am ]
Post subject:  Using HHG for the first time
Hi guys

I'm using HHG for the first time and am loving it! I have a simple question though if someone could help me out:

I've done a search and found that the average clamping time for braces is 2-4 hrs. I clamp my braces in stages so I don't do all the braces at the same time. My method is, glue the top x brace and once set, carve it (first stages of voicing) whilst I glue on the back braces. When the back braces are set I carve them whilst the remainder of the top braces are being glued. (Does any of that make sense idunno )

Anyways, my question is - should I keep the glue warm in the pot at 145 for the 2/3 hrs I'm waiting untill I glue my next braces, or should I let it cool down then re-heat?
Many thanks

Mat.
Author:  Kim [ Tue Jul 27, 2010 5:44 am ]
Post subject:  Re: Using HHG for the first time
Let it cool completely, pop it back in the fridge and reheat when required. It only takes 5 minutes to be read to go again.

Cheers

Kim
Author:  Matthew Jenkins [ Tue Jul 27, 2010 5:48 am ]
Post subject:  Re: Using HHG for the first time
Thanks for the swift reply Kim.

There's so much opinion surrounding HHG. I have read that it's not good to keep re-heating the same batch?? idunno
Author:  Laurent Brondel [ Tue Jul 27, 2010 5:50 am ]
Post subject:  Re: Using HHG for the first time
Matthew Jenkins wrote:
should I keep the glue warm in the pot at 145 for the 2/3 hrs I'm waiting untill I glue my next braces, or should I let it cool down then re-heat?
I leave the glue in the pot all day, everyday, when I'm not finishing. I put it in the fridge at night when I don't forget. I use bottles though, if using a brush in a container you'll need to have a cover and add water once in a while.
Author:  Matthew Jenkins [ Tue Jul 27, 2010 5:54 am ]
Post subject:  Re: Using HHG for the first time
Laurent - Thanks

I'm using plastic bottles. I mix up a small amount at a time (enough to do a few glue jobs). I am keeping it in a baby bottle warmer. Seems to keep the temp very well.
Author:  Matthew Jenkins [ Tue Jul 27, 2010 6:18 am ]
Post subject:  Re: Using HHG for the first time
Thanks Todd
Author:  Kim [ Tue Jul 27, 2010 8:11 am ]
Post subject:  Re: Using HHG for the first time
Todd Stock wrote:
and there is less loss of glue strength than if it is continually heated and cooled.


Sorry Todd but I am yet to see any evidence whatsoever of hide glue losing any determinable bond strength after being taken through continual heating cycles. Aside from hearsay and unqualified assumptions, can you clarify what has led you to this conclusion? Also unless an 'extreme' fall off in bond strength could be shown, I would think that leaving you glue pot at full heat for 3 hours whilst you are otherwise distracted on other unrelated task is somewhat wasteful and hazardous and would certainly make the mix far more incline to require adjustment with water than if it were simply turned off and reheat as required. Works for me anyhow.

Cheers

Kim
Author:  JJ Donohue [ Tue Jul 27, 2010 8:54 am ]
Post subject:  Re: Using HHG for the first time
The longer I use HHG (9 years now) the more I realize how forgiving it really is. Nonetheless, I still use distilled water to dissolve the granules and take care not to overheat. I guess old Good Chemistry Practices are hard to forget. And after all those years, I don't even measure anymore and can adjust the viscosity as needed for the application. On one occasion, the bottle was at 165* for at least 4 hours. Rather than assume that it was damaged, I ran comparative bond tests and found that there was no change. I'm not suggesting that we forget controls, it's just that my assumptions have changed as to how much temperature control is really necessary.

As far as the OPs question...I like to keep my braces gobared at the proper radius for a minimum of 4 hours before carving. As far as heating/reheating or not...you're fine either way IMO as long as you have the viscosity where you like it.
Author:  Kim [ Tue Jul 27, 2010 6:00 pm ]
Post subject:  Re: Using HHG for the first time
Todd Stock wrote:
As for hearsay and unqualified conjecture...I'm a degreed aerospace engineer with grad work in composite structures…the kind you glue. I've been a hand tool woodworker since the age of 13, so at 53, I've spent four decades knee-deep in shavings. Not a glue expert, but I think I can offer an informed opinion on the subject. I also think that folks like Mario Proulx, Ian Kirby, Frank Ford, and a host of others both alive and long dead are equally qualified to offer their opinions on the subject. They may differ from mine in detail (Frank likes zapping glue with the microwave; Mario freezes his; Ian dumps his after a day or two of use and boils the pots out), but that does not cause me to consider their experiences or views on the subject as hearsay or in any way unqualified.


I am no aerospace engineer but at 52 I have spent a good deal of my life working wood Todd, quite a bit of it in full time employment throughout my 20's and 30's, 5 and 6 days a week but I don't think that qualifiers for much in relation to the topic at hand. I think you know full well that my comment regarding hearsay was never intended to dist the experiences or opinion of others, rather it was a valid question relating to my being unaware of any science supporting the notion that there is a clear relationship between a determinable loss of bond strength in HHG, and the number of times that a sample had been cycled through the heating process. I questioned that notion simply because I have not found any evidence to support that during my own extended use of the product. To each his own I suppose.

Cheers

Kim
Author:  Terence Kennedy [ Tue Jul 27, 2010 6:36 pm ]
Post subject:  Re: Using HHG for the first time
I leave my glue pot on all day and eat what's left with supper.
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