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I tried bending maple sides this morning, it seemed to bending quite easily, and while bending the waist, it started to cracked. I bent one side no problem, bent dry and spritzed with water on my bending iron. The sides are 2.2mm thick.

My plan was to glue the crack try using a flat iron to bend the crack down to mate with the side again. Will this work? and what type of glue to use? I was going to use CA glue, but wasn't sure if it would bend. My glue options are CA "Super T" and "Hot Stuff", fish glue and yellow wood glue

A vertical crack that follows the curl can sometimes be sanded out, if it isn't too deep. Then reinforce the inside with a full width brace. If you glue it together you will be able to see the repair. Sometimes it's best to just start over with a new rib set. It depends on how deep the crack is and who is buying the guitar. If the crack is on the inside just glue it , brace it and don't tell any one.

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http://www.cushmanguitars.com/.

A man who carries a cat by the tail learns something he can learn in no other way.
Mark Twain

Your best solution is to scrap the side and start over, hopefully with a matching sister. The next step would be to try to continue to bend while carefully working around the crack (and keeping it clean like Filippo says) then glue the crack with titebond or hide glue after it's bent close to final shape and dried. You can then attempt minor touch up bending in the cracked area but not too much heat as the glue will release. You should expect the crack to show on maple.

I would suggest starting over and experimenting with your technique. Try more water on the wood, change the heat, try less pressure/more pressure, change movements and length of time on the pipe, etc. Hand bending on a pipe is an art and takes practice and experimenting.

Is it a crack or fracture?
Sounds like a fracture.
Fractures can happen when bending with figured woods.
Is the Maple curly/Quilted?

A fracture happens when figured woods especially do
not have a support on the outside of the bend.
Usually they are 10-20mm across but can go right through to
the other side of the side.

Is your side bent to the shape you want it?
If so-
Make cauls that will fit the area.
Inside & outside.

Cover them with wax paper.

Heat the area with a soldering iron wrapped in Alum. foil
This helps with getting the wood to want to go back
where it came from.
apply a clear drying
glue like fish or LMI's white.
Clamp & all should be good if ya did a good
fit of the cauls.

Mike

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Mike Collins

Unless you are planing to paint the guitar it will most likely show through the finish. Maple is that way, just plain hard to hide any type of damage or misstep at all under a clear finish.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Thanks; mike you are right it is a fracture. I was able to glue it and bend it to final shape. The fracture wasn't all the way through the rib. It was figured, all in all I think it may work ok. I will follow your advise on the cauls.

Thanks