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crack
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Author:  jonhfry [ Mon Jul 09, 2007 3:24 am ]
Post subject: 

Thanks to Todd (I think it was him) for the kraft paper idea when bending the sides. My second set bent well and they are beutifully free of resin spots.


The problem:


This side bending gets easier, and this set went well except for a crack. The crack is about 1/3 of the way from the top of the side, it runs with the grain, is about 1 to 1.5 inches long at the butt.


This is where i  am going to glue the tail block, but the crack will still be visible a little bit after trimming and putting in the tail piece.


Should I leave it for now and glue the tail piece and then flood any visible area with glue and dust or try some sort of fix now before I glue in the block ?


Thanks in advance, and one of these days I will post from home and post some picsWink


 


 
Author:  CarltonM [ Mon Jul 09, 2007 3:51 am ]
Post subject: 
Jon,

I'm sure you'll get more experienced advice here, but I'm thinkin' that the best time to repair a crack is when you can squeeze it together and glue it. It'll disappear.
Author:  Michael Dale Payne [ Mon Jul 09, 2007 6:34 am ]
Post subject: 
Yep with the grain, the repair will disappear if done with care.

This often cause when removing the side from the bender if you use a spring loaded hand pull over type lower bout caul and stiff slats. If you do not have a restraint on the sandwich and you slide the hand pull caul back up the toward the waist area the bottom slat wants to spring out and causes a slapping action and this action if unrestrained will easily cause the side to crack along the grain at the lower bout.
Author:  jonhfry [ Mon Jul 09, 2007 7:08 am ]
Post subject: 

Actually, I know what i did.


I think I took too long on the waist and the other side. This is only my second set to bend (first is on the wall as a reminder of what NOT to do  LOL ).  I used kraft paper that was wet, and by the time I got to the bending the lower bout I think the heat had dried most of the moisture. I bent a little too fast and heard it happen. I was glad that was the only crack.


I don't have springs, I have what I call a Ghetto Bender (patent pending). My bender is a typical 1/2 mold with wierd long screws that twist a mahoganey scrap block tight by with lawn mower wheel handles.


Thanks for the input guys,


Now, what type of glue would be best. I seem to have not advanced much beyond the titebond for everything phase yet. I want to ask if other types of glue would be better before i go and use titebond.

Author:  Michael Dale Payne [ Mon Jul 09, 2007 7:51 am ]
Post subject: 
HHG would be best, TB will work and if the crack is tight enough thin CA applied with an extra fine capillary tube will work with darker woods
Author:  jonhfry [ Mon Jul 09, 2007 8:26 am ]
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Being that the side is so thin (about 0.080") what would be the best way to clamp it tight.

Author:  Michael Dale Payne [ Mon Jul 09, 2007 8:38 am ]
Post subject: 
It needs to clamp in a way the holds the crack tight and not flex the side I do this with the assembly mold some wax paper and some bias tape as lashing. I glue the joint and quickly lash it to the assembly mold with the wax paper between the mokd and the side. but not to tightly just enough to close the crack nicely.
Author:  crazymanmichael [ Mon Jul 09, 2007 11:20 am ]
Post subject: 
i would also want the crack supported by a caul clamped to the side to keep it flat against the mold if your are going to do it this way. the caul can easily be made with friendly plastic or bondo.
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