Primitive Archer
Main Discussion Area => Bows => Topic started by: tacticalboxing on September 15, 2018, 10:25:41 am
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I am at the stage at my bow build where I want to steam bend some deflex and reflex into it. This is my first time so I have researched it before trying it but one question in particular was perplexing: many have said to oil it up, some even saying to use bear grease, etc before steaming it and it will steam better, other say not to with steam but to do so with dry heat.
At first I figured, "Hey the extra step may be a little more work but why not to maximize my chance for success." But then I thought, hmm, water and oil indeed do not mix, so what if the oil acted as a barrier to the steam getting it? Still some insist that the oil helps the heat permeate the wood, but really is that true?
I would love to hear what some experienced steamers and benders think about all of this. Please help.
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I've bent bow wood with steam or a heat gun hundreds of times and never used oil ONCE... and never ONCE wished that I had. That tells me it's unnecessary, and I won't unnecessarily soak my bow wood with oil. I try to abide by the oft-given advice 'wet heat for wet wood, dry heat for dry wood'... and while I don't adhere to it 100%, maybe that helps keep me out of trouble.
When I steam selfbow staves, I make sure the bow's backs and ends have 2 good coats of shellac on them. With dry heat, when the wood is dry, often there's no shellac left on it, and it doesn't seem to matter one bit. Practically no issues in 20 years of bending stuff.
Steam doesn't permeate the wood per se, it's more a vehicle to surround and move heat along the wood as it passes by. In fact, steaming a wet/green stave actually draws moisture OUT.
I think folks sometimes have issues because they heat the wood unevenly and/or too quickly... with a heat gun.
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I found that I needed to seal back of bow again with shellac. Steaming will actually dry your stave out and can cause drying checks in its back. Since I started putting a coat of shellac on back just prior to steaming I have eliminated this problem. I'm guessing that's why the use of oil or grease. Could be wrong though.
Bjrogg
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If for example you oil the bow and you use heat gun to induce reflex or you flip the tips, what happens with oily wood afterwards? How do you clean it and does wood soak it up?
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Is this the glued laminate bow you mentioned before?
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Yes, it is the same project, but I have not laminated it yet. I thought I should get the reflex and deflex and straighten it just a bit before the gluing process. That way the steam won't affect the glue. Am I right in thinking this?
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You can glue in the reflex and deflex you need. I haven’t done it, but lots of folks on here do so regularly. I don’t know if it is better or necessary to steam Bend before glue up. Was worried you was already glued up, high heat and glue aren’t a good pair.
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I wouldn't use oil to bend wood that is gonna be laminated
you always have a chance that it'll interfere with the correct gluing
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I have been told that one could glue a bow up in a form and it would keep the shape, glue bending if you will. I considered this, but then had one consideration that needed to be answered before doing so...
As I researched glue bending it seemed that the reflexing that they were doing was more gentle bending, while more daring bends were done with steam.
I want my reflexes a little more on the daring side, almost as much as my Grizzly Bear bow that I have, so I figure I should steam bend it first so I don't crack anything, then afterwards I can glue my bamboo backing on my already reflexed bow, seeing that bamboo is already pretty springy even without heat treating.
The laminate bow that I am attempting is a pyramid style bow, made of white oak with a bamboo backing and bamboo belly. Really River cane from NC to be precise.
How does this sound? Any holes in my logic or thinking in all of this?
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I do much like that when doing a bow with lots of reflex. I steam bend about 2/3 or 3/4 of the bend in and pull the last part in at glue up. You can bend the bamboo a bit with dry heat if you want. It bends very easily. Keep in mind that as you bend the assembly at glue up the bamboo will seem to get longer(inside the bend) and if you have tight recurves the boo can tend to buckle a bit. This only happens if you wrap/clamp it before bending.
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I have been told that one could glue a bow up in a form and it would keep the shape, glue bending if you will. I considered this, but then had one consideration that needed to be answered before doing so...
I have done it many times with kiteboards and it works pretty well but you have to keep in mind that the sheets of wood will retain the bending tension after glued (opposed balanced forces) while if you heat bend the wood is relaxed (no internal tensions after bend)
I'm not sure you may want a pretensioned wood in a bow construction. it may cause too much stress
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I have done it many times with kiteboards and it works pretty well but you have to keep in mind that the sheets of wood will retain the bending tension after glued (opposed balanced forces) while if you heat bend the wood is relaxed (no internal tensions after bend)
I'm not sure you may want a pretensioned wood in a bow construction. it may cause too much stress
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So are you saying that glue bending will leave in the tension from the bend, even while it is static, but steam bending will not?
So does this mean that it will make the bow more fragile when being strung or just that it will increase the draw weight?
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only use oil on dry heat and I use bacon grease....never in steaming or boiling...at least how I do it...gut
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So are you saying that glue bending will leave in the tension from the bend, even while it is static, but steam bending will not?
So does this mean that it will make the bow more fragile when being strung or just that it will increase the draw weight?
Dont know if it will be more fragile (probably yes at the end).
Not sure about draw weight increase either as the layers act in opposed directions
maybe you could do a basic dry or steam bending and then add a little more bend with glue at the end
I would not make an all glue bending on a bow
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Hmm, okay excellent information all around, I think I'm about to just go for it. I have had my set up ready to go for a few weeks I just wanted to make sure I understood the process well before embarking. I just need one clarification first: y'all have said that steam actually dries it the wood and you would put shellac on to give it a barrier on the backing so it wouldn't check.
I wonder if that is why some used the oil, i.e. as a barrier from drying out? Could the oil just be sanded out if it just clings to the surface as some have said?
Anyway, I am not going to use oil, just trying to understand the process and the logic of what bowyers are doing and why.
So, What else could I use besides shellac? Would say duct tape work, just on the backing of course? If not what else?
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sorry didnt see you are laminating this bow.. best to just glue it up with the reflex then.. perry reflex is how I glue mine up... works great.. gut