Crawls Backward (When Alarmed)

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Vintage Princess Banjo Mandolin Crack Repair

Now that the Princess banjo mandolin is lying in state pieces on the workbench I can start fixing the cracks.

First one is this crack on the heel cap.  The cap is a nice pice of birch I think.  It looks like the laminate in the center of the neck underneath began to crack and took the cap with it.

This shot is a little out-of-focus, but still illustrates the point.  You can see the split where the laminate piece - I think that's birch also - began to crack.  Since the cap is glued to that, it also cracked.

So I got some hot hide glue into my syringe.  I'm using a 0.9 mm needle.  I had to thin the glue down - it's not quite water-thin, but close.

The glue has to be thin or it won't pass through the needle.

I squirt the glue into the crack until it starts coming out of the top.

Then I clamped it up in a vise with come cork-faced cauls.  The white paper you see is waxed paper, so the glue won't stick to the cork.

It's hard to tell, but I think the crack on the cap isn't closed all the way.  We shall see what happens.

The next crack is this one on the maple trim piece that covers the laminations on the rim - see the arrow in the picture.

I was gently pulling on the crack to see how far the piece was pulled off the rim.  A couple inches...couple more.  Then, small crack noise and the whole piece popped off.

It's actually better that it came off.  Now I can reglue the whole piece and know it will stay on.

I glued the ends of the trim piece together and clamped them down to dry overnight.

Then I'll be able to attach the piece onto the rim as one assembly, rather than try and deal with the crack at the same time.

The round trim piece is sort of 'springy' and isn't exactly the same size as the rim.  In other words, I have a bit of play in terms of its fit.

So I'm going to glue a small section at a time so it will line up properly.

Brush some hide glue on the rim...

...and align and clamp down that section.

I left this piece to dry and the next night did another small section.  And I started thinking: this is going to take a week at the rate I'm going!

I kept thinking to myself: "self, if you only had a bunch of spool clamps to do this, you could do the whole thing at once!"

Then it hit me: I don't have spool clamps (yet...) but I do have rubber bands!

So I used rubber bands to hold the rim down, with clamps in a couple of recalcitrant sections.

It worked great.  Got it lined up all the way around.

Do you remember the crack in the heel cap?

My first repair closed the crack in the heel itself, but only tightened up the heel cap a little.  I thought that might happen.

So I used my Crawfish Instruments Bridge and Veneer Removal Iron™ to heat the cap.

Careful use of a seam separation knife gets the veneer right off.

Now I can fit the two pieces back together properly.  Which is what I should have done the first time.

Here is is glued up (again).  Should be much better this time.


 
 
 
 

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