Haven't done much guitar building lately with the new bub in the house, Father-in-law falling off the perch three weeks later (massive heart attack, was dead before he hit the ground, or so I'm told. funny thing is, he was just leaving the house on his way to see his cardiologist, fell down in the doorway on his way to the car; he was having a cuppa in my kitchen less that 24 hours before), and well, all the other crap that's been going on around here. I either haven't had time to build or just didn't feel like it when I did.
Anyways; had a hot day here on Saturday - reached 42 Deg C (106F). I went out to the shed on Sunday to find that all the braces on a back that I'd completed a few months ago, had all popped! They're all still glued down in the middle but all the ends had popped off. First time I'd used hide glue, but also the first time the back had been exposed to 106F and 20%RH (maybe a bit hotter in the shed with its corrigated iron roof). So I don't know the reason they popped, but it is a big pain in the bum. I'd left it standing upright so that both sides would see the same conditions too.
I'll post a pic or two later on when I get home from work, but there is dried glue on both the braces and the back, with no wood torn out anywhere.
How hot does it have to get before hot hide glue (good stuff from LMI) lets go? I'm guessing somewhere under 106F, yeah? No problems with titebond.
Moving into the new cooler workspace soon, but I'm not sure I didn't screw up the hhg somehow. I'm assuming for the moment that it was just too bloody hot for the glue.
Shit happens, and just keeps on happening...
Bugger!
-
Paul B
Thanks Hesh, yeah I guess I'd figured as much. Just too damned hot for the glue. Funny though that a completed guitar of mine saw the same temp/RH and nothing bad happened to it. Either a good argument for titebond or for tucking the braces.
Couple years ago on new years day (2005?) it got up to 117F on my shady back porch. Luckily, the porch is about 12' from the pool - which is also partly shaded
Couple years ago on new years day (2005?) it got up to 117F on my shady back porch. Luckily, the porch is about 12' from the pool - which is also partly shaded
-
DarwinStrings
- Blackwood
- Posts: 1877
- Joined: Thu Nov 13, 2008 10:27 pm
- Location: Darwin
Sorry to hear about your father in law Paul. The same thing happened to my partners father a few months ago.
The hide glue and also fish glue let go all the time up here, quality commercial brand guitars fail often and we only ever get to about 35C (95F).
I have always guessed that the high humidity might play a part in it too although in your case it looks more like heat. I never use those protein glues because of it.
Jim
The hide glue and also fish glue let go all the time up here, quality commercial brand guitars fail often and we only ever get to about 35C (95F).
I have always guessed that the high humidity might play a part in it too although in your case it looks more like heat. I never use those protein glues because of it.
Jim
Paul,
Sorry to hear of the Farther in Laws sudden demise, hope all is well for you wife and the young bloke.
HHG has a higher resistance to heat than either white or yellow glue, these will soften, creep and let go in a hot car well before HHG will. One thing that concerns me is that you still have glue on both components. I am not saying this is the case but 'maybe' this could indicate a lack of clamping pressure. One thing that HHG demands is a real close wood to wood fit prior to gluing and to be clamped firm before it has a chance to start gelling.
Cheers
Kim
Sorry to hear of the Farther in Laws sudden demise, hope all is well for you wife and the young bloke.
HHG has a higher resistance to heat than either white or yellow glue, these will soften, creep and let go in a hot car well before HHG will. One thing that concerns me is that you still have glue on both components. I am not saying this is the case but 'maybe' this could indicate a lack of clamping pressure. One thing that HHG demands is a real close wood to wood fit prior to gluing and to be clamped firm before it has a chance to start gelling.
Cheers
Kim
-
Paul B
Thanks for the condolences guys. That's the way I want to go, either in my sleep, or as in Jack's case; like someone just flicked a light switch.
Anyway's, glue: Kim, I used a go bar deck with plenty of pressure and did it all really quickly, heating up the parts prior to gluing. Thought I was pretty well read up on the subject prior to diving in. Maybe too much pressure applied to very tight joints? Could that be worse than not enough?
Or just too bloody hot in the shed.
Maybe the pix will help. Just got a nice new camera for xmas too. I'll post some pix in a couple hours.
Cheers,
Paul.
Anyway's, glue: Kim, I used a go bar deck with plenty of pressure and did it all really quickly, heating up the parts prior to gluing. Thought I was pretty well read up on the subject prior to diving in. Maybe too much pressure applied to very tight joints? Could that be worse than not enough?
Or just too bloody hot in the shed.
Maybe the pix will help. Just got a nice new camera for xmas too. I'll post some pix in a couple hours.
Cheers,
Paul.
If it was 42 outside Paul, I'll bet it was a lot hotter inside. We had a day of 48 in Batemans Bay the year we first arrived in Oz, and inside the workshop it was 60. All that corrugated iron really heats up quick smart. You couldn't even touch a car in the workshop without burning yourself.
As far as a glue joint failing like that, it's a bit of a puzzle. Could be extremely low humidity combined with heat.
We've had plenty of days up here that are 38-41 in the house (don't believe the channel 10 news, we haven't got a clue where they get their readings) and no glue joint failures yet. I'm using 192 gram strength. I apply glue to both surfaces, to make sure that it's not a starved joint, and then in the go-bar deck with as many rods as I think it needs.
Before I got my humidity control in place, I would have a back braced up, then we'd get a wild humidity change and the back would literally turn itself inside out. No joint failure from excess torque on the joint, and as I said, it would be very hot, and as you can imagine, humidity through the roof.
The odd joint that I've had to take apart for one reason or another doesn't really show glue of either surface, They look like the glue has absorbed into the wood, and welded the two pieces together. They really aren't easy to get apart.
Is it possible that this was a "Cold" joint? Glue too thick? It just has me wondering about glue clearly visible on both surfaces.
As far as a glue joint failing like that, it's a bit of a puzzle. Could be extremely low humidity combined with heat.
We've had plenty of days up here that are 38-41 in the house (don't believe the channel 10 news, we haven't got a clue where they get their readings) and no glue joint failures yet. I'm using 192 gram strength. I apply glue to both surfaces, to make sure that it's not a starved joint, and then in the go-bar deck with as many rods as I think it needs.
Before I got my humidity control in place, I would have a back braced up, then we'd get a wild humidity change and the back would literally turn itself inside out. No joint failure from excess torque on the joint, and as I said, it would be very hot, and as you can imagine, humidity through the roof.
The odd joint that I've had to take apart for one reason or another doesn't really show glue of either surface, They look like the glue has absorbed into the wood, and welded the two pieces together. They really aren't easy to get apart.
Is it possible that this was a "Cold" joint? Glue too thick? It just has me wondering about glue clearly visible on both surfaces.
-
Dave White
- Blackwood
- Posts: 452
- Joined: Mon Nov 12, 2007 3:10 am
- Location: Hughenden Valley, England
- Contact:
Paul,
Sorry to hear about your father in laws death but when my time's up an exit like that one would suit me well. It's interesting just how often a birth and death in a family coincides.
As to your glue failure, I don't know if you've already seen it but Frank Ford's glue heat tests are well worth the read. I'm surprised it released "clean" with a dry heat. Usually I need some moisture as well as heat to get hide and fish glues to release and they look like the picture in Frank's article when they do - i.e not clean. My guess would be like Kim's that the glue at the ends gelled before full clamping pressure went on.
But then as Howard Klepper says "It's common wisdom that when hot hide glue joints fail it's down to the gluing technique whereas all other glue joint failures are due to the glue"
The UK is pretty temperate compared to Australia but I will never glue top/back braces until I'm ready to close up a box - 3 to 4 days max in controlled humidity conditions is the longest I'd leave a top or back with braces glues and the carving of the braces I leave until the last possible moment before the box closes. This is trickier to do, I know, if you only have limited time to build over a long period but it's worth trying to plan if you can.
Sorry to hear about your father in laws death but when my time's up an exit like that one would suit me well. It's interesting just how often a birth and death in a family coincides.
As to your glue failure, I don't know if you've already seen it but Frank Ford's glue heat tests are well worth the read. I'm surprised it released "clean" with a dry heat. Usually I need some moisture as well as heat to get hide and fish glues to release and they look like the picture in Frank's article when they do - i.e not clean. My guess would be like Kim's that the glue at the ends gelled before full clamping pressure went on.
But then as Howard Klepper says "It's common wisdom that when hot hide glue joints fail it's down to the gluing technique whereas all other glue joint failures are due to the glue"
The UK is pretty temperate compared to Australia but I will never glue top/back braces until I'm ready to close up a box - 3 to 4 days max in controlled humidity conditions is the longest I'd leave a top or back with braces glues and the carving of the braces I leave until the last possible moment before the box closes. This is trickier to do, I know, if you only have limited time to build over a long period but it's worth trying to plan if you can.
Dave White
[url=http://www.defaoiteguitars.com]De Faoite Stringed Instruments[/url]
[url=http://www.defaoiteguitars.com]De Faoite Stringed Instruments[/url]
-
Paul B
-
Taffy Evans
- Blackwood
- Posts: 1067
- Joined: Wed Apr 30, 2008 6:54 pm
- Location: Charters Towers North Queensland
Hi Paul, sorry to hear of your loss.
After building instruments in Central Australia for a loooong time, and building slowly, as is my way and it's forced on me by bouts of repair work I do the following. After gueing braces on the plates they are held in their respective radius by leaving them in the radius dish with a weight on top or in some other forms that I use until the box is assembled.
After building instruments in Central Australia for a loooong time, and building slowly, as is my way and it's forced on me by bouts of repair work I do the following. After gueing braces on the plates they are held in their respective radius by leaving them in the radius dish with a weight on top or in some other forms that I use until the box is assembled.
Taff
-
Bob Connor
- Admin
- Posts: 3126
- Joined: Mon Jul 09, 2007 9:43 pm
- Location: Geelong, Australia
- Contact:
Condolences to you and your family Paul.
It was 43 here in Geelong today. Temp in the shed was 57 with RH of 8%.
The humidifier hasn't got a snowflakes hope of keeping up with that so we moved anything half built out of it until this heatwave abates.
I reckon it's the heat that's caused the braces to give way. Amazing how much heat will build up under corrugated iron.
It was 43 here in Geelong today. Temp in the shed was 57 with RH of 8%.
The humidifier hasn't got a snowflakes hope of keeping up with that so we moved anything half built out of it until this heatwave abates.
I reckon it's the heat that's caused the braces to give way. Amazing how much heat will build up under corrugated iron.
I'm glad your father-in-law got to hold your son. I lost my mother shortly after my son was born. I still miss her, but the memories of her holding Ryan are still strong and comforting.
Is there no way to insulate your shed or put a roof over the top of it to shade it? It is a common practice in New Mexico to build a freestanding roof over your trailer just for the shade and cooling factor. Just a thought.
Is there no way to insulate your shed or put a roof over the top of it to shade it? It is a common practice in New Mexico to build a freestanding roof over your trailer just for the shade and cooling factor. Just a thought.
-
matthew
- Blackwood
- Posts: 1200
- Joined: Mon Oct 08, 2007 1:16 pm
- Location: Sydney, Inner West
- Contact:
somehow, I don't feel it is good to have anything in an instrument glued up "under tension". Sounds like your braces were glued "pushed down onto" the back, or the other way around, so there is a tendency to spring apart. Otherwise I can't see why the hide glue would give way just like that.
If you didn't glue them under tension, perhaps the back warped under a dryness differential, even though you left it standing up.
the other thing that is possible is a glue-starved joint at the tips, or maybe the clamp up wasn't quite quick enough and the glue had gelled at the tips by the time the clamps went on.
yeah, a bummer. But easy to fix, right?
If you didn't glue them under tension, perhaps the back warped under a dryness differential, even though you left it standing up.
the other thing that is possible is a glue-starved joint at the tips, or maybe the clamp up wasn't quite quick enough and the glue had gelled at the tips by the time the clamps went on.
yeah, a bummer. But easy to fix, right?
Who is online
Users browsing this forum: No registered users and 146 guests