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That I did. Edited my post to correct it.

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http://www.CostaGuitars.com
PMoMC

I built a bending form for this one. Is there a trick to the spacing/amount of the cross pieces?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

No, I decided to get off the pipe.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Oh... I didn't read this after it was edited. I was picturing a wet rag in the pipe and it made sense in a weird way. A wet rag ON the pipe sounds interesting and makes even more sense.

I do wrap it in tin foil after wetting it down, by the way. The tin foil seems like it retains moisture for a really long time too. I need to get a heating blanket, I think. Do I have to buy one from a luthier supply or are there any alternatives that work just as well?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

There is a big problem with your bending form. The metal cross rods are inset from the edge. They are supposed to be tangent to the outline of the guitar. This provides support in the middle of the side. As it is, yours provides no support and the sides will take on a cross bend in various locations and may even crack.

Wise choice.

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http://www.CostaGuitars.com
PMoMC

Barry's right, unless your spring steel cover is really stiff!
Check out my bending form/method in the link in my previous post. It's homemade and a little off the wall (I use light bulbs and a clothes iron as the heat sources), but it works really well. Using the iron to heat the wood directly on the outside of the bends provides support and gives a surprisingly good amount of "feel" as to when the wood is "ready" to bend.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Not sure if I understand what you are saying but...

I made the side pieces from one of my 1/2 templates. I inset the outside edges of the cross pieces roughly .100" (side thickness) + .010" (slat thickness) = .110". That way I could drill holes for the cross pieces without tearing out the sides of the plywood. And that way, the sides would end up being basically flush with the edges of the form once a side and a slat were placed on it.

Is that not good?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Ok. I should also add that sides of the form are 6" apart. The wood I'm bending is 5" or less. Is that what you meant?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Ah ha! Maybe the edges of the guitar side needs to rest on the plywood and the cross pieces just provide support for the middle. Dang it... That's why the bends aren't staying. Because they aren't being bent uniformly.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Nevermind, the way you're doing it will work fine. It's just not the way that's it's usually done.
However, doing it that way, you may need closer spacing on the crossbars, once again depending on the stiffness of your slat.
edit: The slat will tend to have sharper bends where it crosses the supports rather than the smooth curve it should be. Usually the plywood form supports the edges of the slat and eliminates this problem, that's why it's usually done that way.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I'm with you. I think that would be better than the way I'm doing it. I think I am gonna whip up another form. Also, ordered a heating blanket.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

You don't need to make a whole new form, just drill new holes for the cross pieces such that the cross pieces are flush with the sides.

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http://www.CostaGuitars.com
PMoMC

It won't be that difficult. I probably should make new ones because the ones I have now are .110" too big.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Ok.

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http://www.CostaGuitars.com
PMoMC

Too big is Fine just cut or sand them down flush with the bar holes

Check it out... Easy Bake oven for wood!

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Ok, I know this has turned into a side bending thread but I actually have a question about kerfing. I came up with a pretty good system for planing the angle and slotting the lining. The only thing I still am in question about is this -

1.) How wide can/should my kerfs be?

2.) How deep should they be?

I know these are probably a matter of taste but I was just wanting to hear some opinions and methods of others on the forum. The obvious tool for me to use is the table saw with a sled that slots the kerfs similar to how you would do box/finger joints. I just feel like from looking at pictures of other people's linings, the kerfs seem smaller. I've scoured the net to find this info but there seems to be very little out there.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

I use a diablo thin kerf plywood blade from home depot to cut the kerfs. I space them about 1/4" apart and deep enough so there's about .030 to .040 wood left as the strip. Or rather, just thin enough so the lining will bend easily and not crack.

Ray

That's what I'm thinking. I have a plywood blade that I got as a throw in when I purchased another blade. I was using one with a .125" kerf but that just seems too big. Every test piece pretty much shattered in the upper bouts. Not sure if that is a product of the groove size or the spacing between them though.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

I made my own kerfed linings for the first two or three, I refer to the experience as the death of 1000 cuts. (By the way, there's about 1000 kerfs in the linings of a dred )

I now use laminated solid linings, they're easier to make and glue and they work better.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I've been on the fence about his for a while. I don't mind doing the cuts but everything I read indicates that the type of lining used has very little, if any, bearing on the sound of the instrument. I may have to build one of those fancy jigs that cuts veneers down really thin. Can't remember the name. Something French I believe.

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

My way to laminated solid linings is similar to Rodger's. The difference being I never bothered to make any kerfed linings. I got as far as thinking about how I would do all those cuts, it occurred to me that it would be less work to just make and laminate thinner strips. In practice, it take longer to glue them in than it would kerfed linings. I guess it is pretty much a wash. Batching kerfed linings may end up being slightly faster in the long run but it would also be more tedious (IMO) so there is no motivation to switch.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I hear ya. It doesn't really take me that long to do the cuts. I made a sled for the table saw that holds the lining in place with a "tab" that goes into the last notch that I cut. So you do a cut, advance it to the tab, make the next cut and so on. Like box or dovetail joints. I could probably do the thousand cuts or whatever in an hour or so.

The idea of the linings making my sides more rigid intrigues me though. Do rigid sides do anything for tone?

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"I'm not going to say that perfection has never been achieved. However, if it has, it probably went unnoticed due to it's lack of character."

Cutting the kerfs and glueing them in is probably faster than cutting the laminated linings and glueing them in.
Cutting the laminated linings is quicker and less tedious, but then you've got five to glue in instead of one, so the the glueing takes much longer.
The real benifit is the stiffer sides, and a little extra weight in the linings helps the impedence mismatch between the top and sides.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon