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Hello,

I have a few solid bending molds that I made with MDF. Unfortunately I didn't cut the registration bar slot in each piece before gluing up. Has anyone figured out a fancy way to run the completed mold across a router or tablesaw or something in order to cut the slot?

This thing:


I could do it with a hand saw I suspect but I have 5 molds.

Edit: The molds I have are solid, not the bars between two plates.

Brad

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Do yours move on you? Mine are pretty heavy and don’t budge, so I get by with a simple pencil line that I can eyeball between the uprights.

You could also notch it out on the bandsaw.

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If you have a long straight bit you could draw a pencil line across where it goes then cut both sides using a miter gauge (clamping it to the miter gauge to hold alignment) and then cut out the middle with a hand saw.

Hey James,

If I don't pull down the upper and lower bout hold downs at the same time it wants to scoot backward (or forward) a bit. Note, I'm using John Halls universal waist caul which has some flex because of the way it is made.

Good idea on the bandsaw, that could be a safe way to do it.

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I just drill a hole and run a threaded bar and nut though it into the slot for the caul/threaded press.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I like this. That way the waist area isn't compromised by the flat bar on the tight waisted uke's. I will likely go that way.

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You could maybe disregard the slot, drill a 3/8" hole through the mold and bending machine and use a long bolt to keep everything
put. That's how I built mine. Just a thought.

Course, what Colin suggested might work too.

Haha, I know how that feels. I use John's universal bender, too. I changed to some lighter springs before my latest guitar, and they made all the difference. They're still effective, but there's less man-handling involved. I'll measure them when I head out to the garage today. I picked them up at the local Ace, which has an awesome hardware section.

Update: the springs are 4 3/4” body length, 5/8” outer diameter, .065” wire.

Drill press with long 1/4” bit to bore through the mould at end of slot, then cut the shoulders on the bandsaw. Did it that way on my first, and still doing it 8 or 9 moulds later.


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I just screwed a block on each side of the bottom of the mold, between the ends of the bender and it keys into the opening.

B

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My memory is so good, sometimes I remember things that never happened.

I just line mine up with a black sharpie line thru the slot and put a couple of dry wall screws thru the frame and into the side of the mold at the orange tape markers. That keeps it snug up against the side of the frame, and keeps it from moving back and forth. The opening in my screw press frame is about 1/2" wider than the solid bending forms. This makes it easier to get my heat blanket/wood sandwich in and moved into place. I snug it up against one side for the treble side, and slide it over to the other side for bending the bass side.
Ignore the little square window that I cut out. That is a modification so that my size 5, Terz mold will work.

Simplest and effective. Thanks, Colin!



Plus I made a dedicated caul for the uke. Nice and tight in the waist!



Brad


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_________________
Insta - https://www.instagram.com/cbcguitars/
Facebook - https://www.facebook.com/cbcguitars

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.