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When you guys are bending bindings, how wet do you get them before bending? I am bending both ebony and EIRW bindings, both of which already have a laminated purfling strip. I'd like to avoid any accidental delamination if possible.

Thanks!

John

John:
I just did this for the first time with EIR, and didn't use any water during the initial bending using my Fox bender. Then I just moistened lightly with my fingers when touching up on a pipe. Worked great!

-MarkMark Tripp38938.467025463

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John,

I've found that some binding materials -- ebony is one -- tend to bend better when they're pretty wet. It's been a while since I bent ebony. I used a hot pipe then, and was spritzing them frequently. Even then, I broke a couple of pieces because, I guess, they had a bit too much runout.

You should find that EIR bends easily. But even with EIR, I still moisten it lightly.

What I've started doing now, regardless of the ease with which bindings bend, is using Titebond II for my binding/purfling laminations. This has helped a lot in preventing delaminations after they've been wetted.

Best,

Michael

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When bending sides, I have found it is best to use a minimum of water to avoid cupping.
With bindings, this is not a problem. If I'm bending plain bindings with no purfling attached, I get them good & wet & dry 'em out in the bender.
If you have wood that bleeds lots of colour (bloodwood & EIR come to mind) I would recommend minimal wetting. Especially if you have purflings attached.
After a bad experience with bending Ebony & Maple bindings in the same foil wrap, I always bend different coloured woods in seperate wrappings.
If you test a small piece of binding material on your electric (or hot pipe) bender, you'll get a good idea of how much water it needs. I do this now, whenever I set up to bend a new batch of bindings.
If the binding material has lots of runout, I find a really good soaking will minimize breakage in most cases.
I recently bent a set of African Blackwood bindings which needed no water at all. When I tested a piece on the hot pipe, it formed like warm plastic, even at .095" thickness.
I've used other woods (Ebony, in particular) which needed to be coaxed into shape with lots of water & patience.

I just bent a set of ebony bindings witha white lamination yesterday in my Blues Creek bender. I had used a plain ebony strip for the backstrip on a Black Acacia back and found that the ebony was brittle enough to justify wetting. I sprayed the strips pretty liberally, waited until they stopped dripping, and bent the four pieces side by side in my Blues Creek bender. I had no color bleed or delamination. I didn't keep the temperature high for as long as I did when I bend sides. That may have helped prevent delamination.

Paul

Paul D38938.8465740741

bending binding isn't to difficult but as some of the postings are showing , there is differences in how much water to what wood.
   I find that if I am bending dry I want more heat. You need to understand what is happening. Water isn't so much cooking the wood but making the heat more uniform to make the wood bend. the water makes the atmosphere denser in the binding environmet and the heat penetrates faster and deeper ,=.
Water can be both friend and enemy. Some woods , like maple are dry benders, just use a little water to get the steam to help the heat penetrate. Using wet paper allows more steam without over soaking the wood. Ebony also is a hot bender and springbacker so use higher heat ( 320-350).
   I am trying to compile wood info so in the future you can use this info as a base. Mahogany will spring back more than some woods and needs to be heated to about 350-375 for 10 minutes after drying. Maple especially figured needs to be heated a bit before bending. I like to get it at 325 for about 5 minutes then bend. While I will add a bit of water from a spray bottle that is more to help keep the wood uniform in heat.
   Water boils of at a constant of 212 and this way the wood will react evenly. wood that has cold spots can deform at the main focus points and possibly crack.
   Gee what I have learned in the years of bending. thickness is also somthing you need to consider. Bob Gleason has helped me with some of his tricks. He introduced me to the wet Kraft paper.
    Here are some simple rules
low heat   225-250
med heat 250-300
high      325 - 370
    dry bending   use just enough water to creat steam
    wet bending   using wet paper
Mahogany med wet to med-high heat
ebony    high
rosewood   butter
figured   wet   med heat. then a good 20 dry cycle ( 170-200 degrees 0

I like to let the wood in the bender about 1 hr after cooling to help hole shape then set it in a mold for 24 hrs
john hall

Thank you very much John, that is going to be very useful information!