Acoustic Vibes MusicFreeMandolinVideos.comGypsys MusicJanet Davis MusicLakota LeathersMandolin Strings and BeyondClark Mandolins
Go Back   Mandolin Cafe Message Board > Instruments and Equipment > Builders and Repair

Builders and Repair Discussions for those with an interest in the construction and repair of mandolin family instruments.

Reply
 
Thread Tools
Old 04-16-2009, 11:03 PM   #1
Mike Black
Formerly: Summit33
 
Mike Black's Avatar
 
Join Date: Nov 2007
Location: Lawrence, KS
Posts: 259
Default Glue seam joint / Re-glue?

My perfectionism maybe showing through here, but at lest I'm willing to admit it, and that's the first step right.

Anyway...I guess I didn't get this joint as perfect as I thought I did before I glued it up. After rough carving it It seams as if the joint was better on the edges than the middle. I now have a hair-line seam between the pieces. It's cut to shape with a little play room and I have the outside arch carved, but NOT the inside.

My question is: Should I try to heat the joint to seperate the seam and re-glue it? Or should I just leave it alone? The seam was glued together with regular tightbond.

Anyone have experience doing this rework?

Thanks in advance!
Attached Thumbnails
Click image for larger version

Name:	Octave seam 1.jpg
Views:	83
Size:	96.2 KB
ID:	41306   Click image for larger version

Name:	Octave seam 2.jpg
Views:	85
Size:	38.0 KB
ID:	41307  
__________________
Mike Black

Mike Black Mandolins
http://www.threebeansalad.net
Mike Black is offline   Reply With Quote
Old 04-16-2009, 11:24 PM   #2
sunburst
Registered User
 
Join Date: Nov 2003
Location: Virginia
Posts: 7,560
Default Re: Glue seam joint / Re-glue?

Good pictures!

I believe I'd redo that one if there's enough wood. I would rip it apart, though, rather than trying to heat the glue joint, but I have a thin kerf blade. You might be able to heat it apart without too much warping, but I don't know.

Did you start with wedge shaped pieces?
If you were jointing and clamping wedge shaped pieces, that can lead to the joint opening on the angled (not the flat) side of the piece, and the joint will be loose in the center after carving.

If you redo it with it already cut to shape, it will be even more difficult to get a good joint, so work carefully!
This might be a good time to get some scrap wood, some hide glue, and learn to do rubbed joints before you do that back over.
__________________
John Hamlett
www.hamlettinstruments.com
sunburst is online now   Reply With Quote
Old 04-17-2009, 07:22 AM   #3
Tony Francis
Registered User
 
Join Date: Aug 2008
Posts: 32
Default Re: Glue seam joint / Re-glue?

I agree with John, re do it.

If there is any doubt in your mind, re do it, and make a note of it so next time not to make that same mistake again. Its easy enough to fix now, much harder down the track.

Best,

Tony
Tony Francis is offline   Reply With Quote
Old 04-17-2009, 09:52 AM   #4
Mike Black
Formerly: Summit33
 
Mike Black's Avatar
 
Join Date: Nov 2007
Location: Lawrence, KS
Posts: 259
Default Re: Glue seam joint / Re-glue?

Any suggestions on what to use to get them apart if I don't have a thin kerf blade?
__________________
Mike Black

Mike Black Mandolins
http://www.threebeansalad.net
Mike Black is offline   Reply With Quote
Old 04-17-2009, 10:25 AM   #5
sunburst
Registered User
 
Join Date: Nov 2003
Location: Virginia
Posts: 7,560
Default Re: Glue seam joint / Re-glue?

How much wood do you have to spare? Do you have a good bandsaw that you can set up for a precise cut with a small blade?
If you have plenty of wood you can rip it with a table saw with a regular, not thin kerf, blade. Double stick tape or hot melt it to a piece of plywood or lumber so you can use the saw fence. You'll lose a little more than 1/8" doing it that way, and perhaps a little less than 1/8" with a good bandsaw.
__________________
John Hamlett
www.hamlettinstruments.com
sunburst is online now   Reply With Quote
Old 04-17-2009, 01:26 PM   #6
Lefty Luthier
Registered User
 
Join Date: Apr 2009
Location: Spring Branch, Texas
Posts: 374
Default Re: Glue seam joint / Re-glue?

I too suggest recutting the joint. If the grain is reasonably straight and you have at least 0.25 inch margin, just take a heavy chisel and split along that joint. Then run both pieces through your jointer and reglue. Based on bitter experience, never attempt this type of fix with maple or walnut backboards, always saw them apart.
Lefty Luthier is online now   Reply With Quote
Old 04-17-2009, 02:51 PM   #7
Mike Black
Formerly: Summit33
 
Mike Black's Avatar
 
Join Date: Nov 2007
Location: Lawrence, KS
Posts: 259
Default Re: Glue seam joint / Re-glue?

Since this is a quilted maple board, you suggest that I saw it then? I don't have a table saw so I'll have to work slowly with my bandsaw. Wish me luck!
__________________
Mike Black

Mike Black Mandolins
http://www.threebeansalad.net
Mike Black is offline   Reply With Quote
Old 04-17-2009, 03:42 PM   #8
sunburst
Registered User
 
Join Date: Nov 2003
Location: Virginia
Posts: 7,560
Default Re: Glue seam joint / Re-glue?

Use a fence on the bandsaw. All you need is a straight board clamped to the table and a board or piece of plywood with a straight edge to fasten the back to. Be sure the center seam is exactly parallel to the edge of your board and set your fence so that the blade tracks right down the center of your glue joint. After you've ripped the halves apart, then joint them again.
__________________
John Hamlett
www.hamlettinstruments.com
sunburst is online now   Reply With Quote
Old 04-17-2009, 06:25 PM   #9
Mike Black
Formerly: Summit33
 
Mike Black's Avatar
 
Join Date: Nov 2007
Location: Lawrence, KS
Posts: 259
Default Re: Glue seam joint / Re-glue?

John...Thanks for the tip about attaching it to a board first. It worked like a dream. I've got the seam apart and smoothed back up and it won't be too small. I still had some room (at lest a skosh or more). I think that i'll look a lot better this time.

Now I just got to work on that hide glue rubbed joint.

Practice, practice practice....
__________________
Mike Black

Mike Black Mandolins
http://www.threebeansalad.net
Mike Black is offline   Reply With Quote
Reply

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 09:40 AM.


© Mandolin Cafe