bending black limba

seangil · #1 07-24-2021, 01:03 PM

I'm working on two OM sized acoustics and have some very pretty black limba for back and sides. I'm at the point of being ready to bend, but I have never worked with Black Limba and haven't found much online.

Does anyone have experience bending it? If so, what worked for you in terms of side thickness, heat, and your bending setup? I've got a fox bender, but could also try a clumsy hand at a bending iron.

phavriluk · #2 07-24-2021, 02:14 PM

I've had no surprises bending that wood in my Fox bender. .080" thick, bend the waist on a pipe, finish the bends in the Fox bender at 300 degrees f.

buzzsawlouie · #3 08-11-2021, 10:16 AM

@seangil. Did you have any luck with your bending? I just tried to bend some black limba by hand and did not go well, but full disclosure I am a noob at this so... The problem I had was the sides started to split along the grain lines so I stopped before i got the full bends in. I am getting new sides and I have a local luthier that has offered to use his fox bender, so just wanted to see if you used the 300 degrees that phavriluk suggested or any other tips you may have discovered?

printer2 · #4 08-14-2021, 07:12 AM

That suggests runout. Do you use much water? Use a back strap when hand bending?

seangil · #5 08-21-2021, 02:44 PM

I haven't tried bending yet, but will within the next few weeks. I have another parlor guitar which I want to progress a bit farther before turning to the other OM / limba guitar that is on my bench.

I have a fox bender, but also have tried a iron and liked that as well. I am trying to find someone looking to sell their bending iron since I have a feel that I will ultimately prefer to go that route than the Fox. So far, my experience with the Fox has been that it gets the wood mostly there, but I still end up going back to a bending iron. So I am thinking that I might be better off just learning to use the iron properly.

BlackLotusWood · #6 08-21-2021, 11:26 PM

You want to use a higher temp with a iron, than someone using a fox style bender. On mine I usually am around 450-500 and I keep a damp paper towel on pipe. Any lower than that and I've had issues with cracking.
~Beauty & Peace~
Kyle-

seangil · #7 12-22-2021, 03:45 PM

I tried using a Fox bender, but had quite considerable springback and used a bending iron to try to wrestle the wood into shape. It proved quite difficult to work with as compared to walnut. Not sure if it was me or the wood. I tried using the bender on it 2 or 3 times at increasing durations (12 mins under heat and then cooling down and staying in the mold for a week). However, it just wouldn't take the shape of the form completely. The waist was great. It was just the ends that were a problem.

phavriluk · #8 12-22-2021, 11:20 PM

That's what a building mold and spreaders are for. After the kerfing is installed and the blocks at either end are installed, the sides get resigned to their fate. It all works out, springback happens and it's not any kind of catastrophe.

redir · #9 12-23-2021, 08:59 AM

I have found that after using my bending machine I have to touch up on a hot pipe anyway. The machine gets the bulk of it done though.

seangil · #10 12-25-2021, 10:14 AM

Quote:

Originally Posted by phavriluk

That's what a building mold and spreaders are for. After the kerfing is installed and the blocks at either end are installed, the sides get resigned to their fate. It all works out, springback happens and it's not any kind of catastrophe.

I've been trying my hand at only using a pipe and actually am finding that I can get less spring back than I do with my bender. I'm going to hang onto my bender, but think that I will move to doing it all by hand. I've seen videos of people who are really experienced and can do a pair of sides in 20 minutes. I'm not there yet, but can see that it is achievable. I'll keep the bender as a fallback /insurance option.