The Luthier Community

Psssst Gary, I'll tell ya a secret;

It ain't me, it's The MandoManiac Bending System, S'Truth!

That always stinks to see wood with a crack! The bending blanket is different for everyone I think......it all depends on when and how you clamp it down. Some people think I am nuts for bending at 260 but I have not cracked a set since going down to that temp.

I always enjoy seeing your eye for balance and contrasting colors and lines. Very tasteful~

~B

Hi Ray, glad to see ya starting another build!
Just to touch base with ya, how thick is your sides I had a problem trying to bend some bubinga. I thined my sides down just a little more and bam bent like butter!

If your cutaway is not at .080 or less this is the golden number they need to be for bending cutaways.

I hope things work out on the next side!

Thxs
Hugh

I only went down to .085. Their cooling down now so we'll see...

Raymond

Brian wrote:That always stinks to see wood with a crack! The bending blanket is different for everyone I think......it all depends on when and how you clamp it down. Some people think I am nuts for bending at 260 but I have not cracked a set since going down to that temp.

I always enjoy seeing your eye for balance and contrasting colors and lines. Very tasteful~

~B

Thanks Brian. This one was easy because I'm basically copying the one from before. And that one had alot of input from Steve Stevens.

Raymond

Well let's start with some good news.

Remember the cracked cutaway?


Well here is what it looks like after some epoxy. (I use epoxy filler so the glue won't show in the end)



And the 2nd set is from the same billet which was pretty well on qtr so worst case I can use the repaired cutaway and still get a bookmatch.


So I ran the sides through my drum sander .085 for the cutaway and .090 for the non-cutaway.

Sorry about the picture but the camera autofocused on the bench...


Bent the cutaway first



And busted it even worse than the first!!!


The crack at the bottom of the first picture actually goes all the way through the side. but closes up tight with very little pressure. The others are more surface only and should close up nicely with a little clamping. Because I hate to throw anything away, I slapped some epoxy on it and clamped it up as best I could, but I'll use the repaired first one

I think Dennis might have the right problem but different cause. I think the metal slats distribute the load sufficiently, but they are thicker than the spring steel slats that Steve Stevens uses (that he got from Mandomaniac). At Steve's you can see the wood sag as it gets ready to bend, while I don't see any sag, Also at Steve's I can feel the wood give under my hand as it starts to bend while with mine I only feel the resistance of the slats. I'm going to order some like Steve has. He gave me the can they came in so I'll get the specs and someone gave a link to a site that sells them... Keep in mind though that at Steve's I'm also 1 for 2. The purpleheart bent fine, but the Paduak cracked. And I did bend the rosewood cutaway without cracking it using this same rig as today.

Meanwhile I bent the second side...



Since I can't see the sag or feel the wood give under pressure, I set the temperature for 325 and let it soak at that temperature for 15 of the 20 minutes, then bent it. Seemed to go smoother but only time will tell. It's cooling from it's second cycle at the moment.

I also cut a slot in the mold so the cutaway can extend a little long.

and glued the neck block to the cutaway. After it dries I will trim off the excess. I don't worry about a mitre since the edge gets binding anyway.


Raymond

Wow Raymond,

That is rough! Shows you have heart though, keeping on, and sharing your setbacks with us as well as your successes.
Good to see that the first side repaired so well. Overcoming these obstacles seem to be what building is all about. The creative recovery.

Thanks,
Joe

Thanks Joe.

I plan to download this build thread and clean it up and give it to the customer with the guitar. I'll probably delete some of the open discussion about my screw-ups then so the customer won't worry too much...

I have to add that this maple has a lot of tight curl in it and just like the Paduak, all the cracking seems to be along a curl or change in the grain. That's why Steve keeps suggesting that I pick a calmer grain wood to work with (like the purpleheart, but not purpleheart ). Unfortunately the customer specifically wanted curly maple this time.

Onward and upward...

Raymond