Hello everyone, i recently purchased a Hana Lima Tenor uke kit. So i am currently in the process of making the jigs i will need to hopefully build a uke that sounds and plays nice.

My Question is:

When using the tenor plans i recieved with my kit, do i cut the outline of my jig to the exact size of the outside of my ukulele plans or do i make it slightly smaller to take into account the wood, metal and blanket.

If i do make it smaller should i use the inside line from the plans.

Thanks, Alex

Thanks mblue, how much did you compensate?

Alex:

Bend is not a precise science.  You will probably get some spring back after bending on the jig.

I used the line for the inside of the lining on the plans as the template line for constructing my bender and it worked out well.

Don

Some really good ideas, guys.

I'm about to build my side bending jig and I'm thinking of maiking the mold form slightly wider than the width of two sides so I can bend both of them at the same time.

Most commercial ones don't appear to do this but I saw the idea executed somewhere. It would save time because you're bending both sides simultaneously and you should (theoretically) get the same shape in both pieces.

But I see some drawbacks in that it may make it harder to get both sides aligned properly and would certainly require more pressure from the end and waist clamps. Might be other issues I'm not foreseeing.

What are your opinions of this idea? Or should I stick with bending one side at a time?

Also, anyone have experience using incandescent light bulbs as a heat source within the jig as opposed to the heat blanket? I'm thinking of putting 3 ceramic bulb sockets evenly spaced inside the jig and covering the wood inside with aluminum foil to prevent the jig wood from being scorched. The sockets are rated for up to 600W each - though I wouldn't put bulbs of that wattage in them. Probably more like 150 watts each.

On a Home Depot trip I bought some perforated aluminum sheet to make the part of the form that the sides will rest upon during the heating process. I figure this will allow a fairly solid surface for the sides, let the heat through, and also allow the steam to escape. I'll use a solid sheet of stainless steel as the top cover over the sides as they are being bent to trap the heat and steam in the wood below it. It seems to make sense in my head, but I may be looking at the dynamics of it all wrong. Again, opinions?

I bought a neat little digital thermomenter yesterday that has a remote probe and several alarm capabilites and a BIG (2" high) readout. It can measure temps up to 400 degrees. and can sound an alarm when a specific temp has been reached or exceeded. It was just $40. Anyone interested in it let me know.

Mahalo!
Jeff

Thanks, Bob.

I just saw a video of a guy using a Fox bender to bend mahogany sides for a guitar. He blanketed the wood between wet kraft paper, aluminum foil, stainless steel slats, and a heating blanket on top and set the whole sandwich on the form with the waist mark under the waist caul. He let the temp get up to 370 using a temp probe stuck between the sandwich. He watched for steam to rise then slowly brought the waist caul down to about 1/2 inch above the form, then pulled the bottom caul carefully down over the bottom of the form. Then he set the top caul. That done, he tightened down the waist caul and let it "cook" for 15 minutes.

After 12 hours, he removed the wood and had a perfect bend. Very nice process. I'm now thinking of translating that process to the light bulb heat source instead of a heat blanket. My bender will be similar to the Fox bender, designed so that different size forms - from soprano uke to dreadnought guitar - can be mounted in it.

Jeff

Jeff

I bend sides for guitars or ukes at the rate of about 1 per week.  I use a heat blanket, and make my bending forms the thicknes of the sides smaller than the outline.  Remember that it is the heat, and not the water, that makes the sides soft enough to bend.  I bend between 2 sheets of stainless steel, which I get from a commercial kitchen supply place for about $10 a pair.  Put the probe from the thermometer between the blanket and steel, as it can stain.  If I am using a really high oil wood, I do wrap in brown paper to avoid staining.
I got my bender from blues creek guitars, and block it up to handle ukes.  I just finished a kasha baritone/ cutaway in rosewood, and had no problems with the bend.  I can't imagine why you would need to bend both sides at once.  I bend between 250 and 290 F
You can see me bending a rosewood side for a guitar at my web site www.hastingsmade.com under the media section.  I built my first 2 ukes just using an iron, but it is so easy to make bending forms, that I now have forms for all the ukes I build.  I just make a single 1/2 pattern in some high quality 1/2" plywood, using a band saw, and spindle sander.  Now take this pattern, and cut 3/4" plywood close to the line, and then use a flush cutting router bit to make all coppies exact. for a uke I make 3 pieces, screm together using 1 1/4" spacers to get a bending form just over 4" wide.
Hope this helps, I find it is plenty of work to bend 1 side at a time, and do it acurately!
Jack

The rod under the waste is actually a 1/2" bolt which I use on all of my forms to hold them from moving in the bender.  I move the springs arround, based on the size of the body.  My center caul is made by blues creek and I think he has applied for a patent.  It is a piece of heavy gauge stainless in a loop, and you can adjust radius by placing dowels of various diameters inside.
good luck
by the way, I had a fox bender with light bulbs (3x150) and switched to blues creek with the heat blacket, and sold my fox.  Charels Fox is a great guy, but I think some of the other suppliers, are as good or better, for less money.