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Hi

So bent the sides for the first time and had a mare

First one was fine ... my equipment was very questionable (used a floor steamer ) but seemed to work

Noticed the second one has cracked on the tight upper bout curve whilst in the mold

Its not gone through but has splintered out a bit on the outside and has almost a crease in the wood

Is this salvageable. .if so whats the best way forward?

Its now in a mold and think really it needs to stay there until kerfings on as anymore bending could push it (and me) over the edge

Cheers

Photo would help. Sometimes splintering can be glued but if the side is creased at the crack it's probably time for a new side.

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Steve Smith
"Music is what feelings sound like"

Yes creased at crack.. wondered id i could sand it out and or fill if it opens at all..
Photos on its way

Not cracked through but can feel a definite bump when running finger over it and slight splintering

Have superglued the inside of crease to give some strength

Is it on the bass or treble side? If the bass, you could cut most of it out with a soundport, and put the reinforcing veneers inside. Then you'd have enough structure behind to sand out the crease without compromising the side - depending on how sharp the angle is of course. I did this recently on a ukulele I'm building that cracked where a screw had previously been inserted (it's made from salvaged wood).

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Thanks pete but its the treble side unfortunately

Unless its a total practice gig -- time for new sides. But before that, get/make a good side bender, something like this is only a few $$:

http://www.acousticguitarconstructionfo ... ?f=8&t=794

Edit to indicated that the link is for a pipe style bender made from a small heat blanket.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Ken, I did not see a side bender in that link. Lots of cool stuff though.

To the OP, what is a floor steamer? I've had cracks like that. I have never been able to sand them out. They "telegraph" their presence no matter what I tried. But somebody might have an idea. A lot of us use a sidebender (very similar to what John sells at Bluescreek). The plans are available on line if you want to go the DIY route. I did. A lot of us did. I rebuilt it once when I switched from light bulbs to heat blankets. You don't need exotic plywoods, but some do use Baltic birch. I used MDF in parts of it. One day I'm going to start over and build one from Baltic. Bending is about getting the wood hot enough that it becomes "plastic". Super Soft is a spray that veneer workers use to aid in the process. Again, a number of us use that. Very effective. Good luck and don't worry too much about mistakes like this. Just try again.

Mike

Thanks Mike, The link is for the construction of a pipe style bender made from a small inexpensive heat blanket. I edited the post.

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Ken Cierp

http://www.kennethmichaelguitars.com/

How many watts are you guys using?

How many watts? Not sure. Go to Bluescreek website. I think john lists it there. They do get quite hot. You can easily hit 400 degrees (don't let it though)

How about changing to a pointy style cutaway? Cut out the cracked part, and you might be able to simply flip the upper piece around and use it directly. Or you might need to bend it some, or it might be too short and then you'll need a new piece. But it would look kind of cool to have a different wood in the cutaway. LMI has 9x5" ebony headplates that should work, if you don't have any suitable pieces lying around or local places to buy from.

I'd recommend getting a hot pipe bender of some sort. Even if you do get a heating blanket bending machine as well, it's good to have a pipe to touch things up or do unusual bends. A cheap one can be made with an electric charcoal starter squeezed in a vise, and then put in a scrap of exhaust pipe from a local muffler shop. Mine is 3" diameter, and I drilled 4 holes in the pipe and used some L brackets and nuts and bolts and screws to attach it to a board for easier mounting.

On the cracked side, why not bend it to close the crack and give it some CA? Put some poly film on the crack and press the fibers together and hold till the CA sets.

"I'd recommend getting a hot pipe bender of some sort. Even if you do get a heating blanket bending machine as well, it's good to have a pipe to touch things up or do unusual bends. A cheap one can be made with an electric charcoal starter squeezed in a vise, and then put in a scrap of exhaust pipe from a local muffler shop. Mine is 3" diameter, and I drilled 4 holes in the pipe and used some L brackets and nuts and bolts and screws to attach it to a board for easier mounting."

+1. Mine is made with a scrap of aluminum pipe (called "conduit") from a salvage yard. You'll probably one for touch-up anyway, and it's not too hard to do all the bending needed on the easier woods (Indian rosewood, walnut) just with the pipe bender.

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Tim Allen
"Never hurry, never rest."

A florentine cutaway is like a whole new level of difficulty. Though that is a creative suggestion DK. I'm kind of thinking the OP has got to get a foundation in bending, whether on a hot pipe or on a side bender jig. I'm still trying to figure out how he used a floor steamer to get as far as he did. I googled floor steamers and all I can up with was these mop looking things for cleaning hardwood floors. I've got a small box of cracked sides. There's always a use for that wood

Btw, my hot pipe is a 3" piece of zinc coated iron pipe (yes, I am aware of the vapor issue. I never get it that hot), and a propane torch. All in a metal vise. I'd upgrade, but I only bend and tweak binding sized stuff with it.

i'm with dennis on this one. its not a bad idea to start practicing on a hot pipe, because it is so hands on you'll really get a sense for how wood feels when it wants to bend and when it doesn't.

if it were me i'd start another set, after practicing a bit. you are going to put so much time and effort and money into this guitar you want to be happy with it at the end. i cracked the second of my sides the first time bending and i just put it aside and tried again. and then the first time i tried a venetian cut away i cracked that too. both times the sides were too thick.

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Hi Mike yes its the floor steamer you saw..except with a load attachments. . I used a small cup type attachment (for tiles?) Which covered the wood area in steam. Like i said it bent the first side ok.. it took time though

Before that i tried on scrap a 3" pipe with gas torch inside and had very poor results so felt a little more confident with the slower steaming method.
Also built a steam box but with poor results on scrap.
Then had success with steamer on scrap so went with that

I had to use an old om guitar as a guide to the shape by molding it to outside of the guitar.. this may have been a factor as the sides would have been slightly bigger than the final mold

Not enjoying this part of the build at all.. seems without decent bending gear or some expertise on a pipe it may be a step to far for me

Heyho

The steamer in question




Stole it from the wife ..hence the pink

Just took it out of the mold and its not to bad. .but a definite crease..

Some more pics of crease

I would get another side. I applaud your ingenuity for getting to this point. I went through several sets of sides when doing the bends on my first and I understand the frustration but if you keep working at it you will get it.

_________________
Steve Smith
"Music is what feelings sound like"

You pipe bender - is the pipe partially blocked at the end to keep the heat in or does it just go straight through?

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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 have a few pipes (various diameters) - all open, but I use an electric charcoal igniter.

Need to build or find a temperature control though, but I don't want to just shunt current with a rheostat.

Maybe a router speed controller? I wonder if the pulsing would be bad for it or anything...

Currently I just unplug it for a minute when the pipe gets too hot

Ideal would be like a hair curling iron I've used before, which has an internal thermometer and digital temperature control, to automatically adjust the heating element and maintain the selected temperature regardless of whether something is currently in contact with it or not. Really nice, compared to controlling by power level, which will get too hot if you spend too much time checking against your pattern, or get too cold if you turn it down and then touch the wood to it (especially with water).

Well, that's a very creative idea. Two thoughts. If u are stateside, order a bottle of Super Soft II. Spray on wood, wrap in paper towels, wrap that in foil, let set for 24 hours. Then, instead of using the body itself, make a tracing on plywood. One half the body, bring it in the thickness of your wood. Join two sides of plywood every 1.5-2" with spars. Now u will have an appropriately sized mold, strong work surface, and guarantee symmetry by using a single half mold.

I stick a cut off beer can to cap off the pipe end. Why waste the heat? Plus it would get real hot coming out the other side I would think.

To the OP... It's toast my friend. I did something similiar to that on my second or third guitar, well it broke in a different manner, the assembly fell off my work bench and cracked the sides, but it was toast. I decided to hang up the broken hoop on a hook in the corner of my shop as a subtle reminder to be careful. About 20 years later I looked at the guitar hoop in the corner and thought hmmm. Now she is a cutout classical guitar.

So if I were you I'd deal with your mistakes and just start over with the proper equipment. Keep that one around and maybe one day you can build it up as a cut out or possible even a weird looking parlor guitar or something interesting.