Author Topic: New heat treating method??  (Read 59712 times)

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Offline kbear

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Re: New heat treating method??
« Reply #45 on: August 24, 2019, 04:14:29 pm »
A couple of years ago I did some experimenting with a process called "malming". The idea was to introduce resins into the belly of the bow whilst heat treating, that would support the belly, reduce set, and increase cast. I was using colophony dissolved in gum turps and brushing it on the belly with a manilla rope (doesn't melt) whilst applying high heat (400 C). It smelled great! The end result looked very much like what you see in the video at 0:23. The bow was clamped to a form at the handle and tips, in reflex, and slats  of thin wood clamped to the profile of the bow. This created a channel that the heat would follow, and serve to increase heat on the belly, but protect the back. I did notice some improvement in cast and reduction in set.

Perhaps he has "re-discovered" malming?

It should be noted that I am using the term "malming" fairly liberally here. The actual process of malming is far more complicated than what I have been trying. I have simply been trying to mimic this process.

John gives a great explanation of the actual process here:

https://www.primitivearcher.com/smf/index.php/topic,64701.msg910032.html#msg910032


Offline PatM

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Re: New heat treating method??
« Reply #46 on: August 24, 2019, 06:24:40 pm »
Yeah, Marc  did  this too many years ago.
« Last Edit: August 24, 2019, 06:48:30 pm by PatM »

Offline sleek

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Re: New heat treating method??
« Reply #47 on: August 24, 2019, 06:46:27 pm »
A couple of years ago I did some experimenting with a process called "malming". The idea was to introduce resins into the belly of the bow whilst heat treating, that would support the belly, reduce set, and increase cast. I was using colophony dissolved in gum turps and brushing it on the belly with a manilla rope (doesn't melt) whilst applying high heat (400 C). It smelled great! The end result looked very much like what you see in the video at 0:23. The bow was clamped to a form at the handle and tips, in reflex, and slats  of thin wood clamped to the profile of the bow. This created a channel that the heat would follow, and serve to increase heat on the belly, but protect the back. I did notice some improvement in cast and reduction in set.

Perhaps he has "re-discovered" malming?

It should be noted that I am using the term "malming" fairly liberally here. The actual process of malming is far more complicated than what I have been trying. I have simply been trying to mimic this process.

John gives a great explanation of the actual process here:

https://www.primitivearcher.com/smf/index.php/topic,64701.msg910032.html#msg910032

Faaaaascinating link and idea. Just yesterday I was thinking about how to disolve hide glue into a volatile solvent for this very purpose. I went to walmart this morning and am now getting ready to try acetone. I was thinking if I can fill the void between the fibers they would resist compression failure much better. Also considering water and sugar, letting it soak in until a specific density has been set, then cook the belly hard with heat, melting the sugars in it to the fibers, crystallizing them in there much like you do with carbon in steel when hardening it.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline PatM

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Re: New heat treating method??
« Reply #48 on: August 24, 2019, 06:53:04 pm »
   Now you're just talking about the same idea of resin impregnation of wood which is a well known process.  Now it is done with artificial resin.

 Osage and Yew basically have this naturally.

 Bamboo flyrod makers have documented how impregnated rods hold their shape better and are more moisture resistant.   They usually use proprietary mixtures of various substances and a vacuum chamber to draw it into the fibers.

Offline sleek

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Re: New heat treating method??
« Reply #49 on: August 24, 2019, 07:08:57 pm »
   Now you're just talking about the same idea of resin impregnation of wood which is a well known process.  Now it is done with artificial resin.

 Osage and Yew basically have this naturally.

 Bamboo flyrod makers have documented how impregnated rods hold their shape better and are more moisture resistant.   They usually use proprietary mixtures of various substances and a vacuum chamber to draw it into the fibers.

BUT... BUT... BUT... Mine is new never heard of, and better than anything you can think of!


Yeah, I didnt know about all that, But I do know about artificial resin impregnated wood. I was hoping to do it naturally.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline burchett.donald

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Re: New heat treating method??
« Reply #50 on: August 24, 2019, 07:33:37 pm »
  Looks like Thad is impressed and that says a lot from my perspective...I guess when the DVD comes out we will see?
                                                                                                                                                                           
                                                                                                     
Genesis 27:3 Now therefore take, I pray thee, thy weapons, thy quiver and thy bow, and go out to the field, and take me some venison;

Offline PatM

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Re: New heat treating method??
« Reply #51 on: August 24, 2019, 07:34:56 pm »
Make up a hard drying natural varnish mixture  and draw it into the wood   Will it be disqualified if you use a vacuum or pressure chamber?

Offline sleek

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Re: New heat treating method??
« Reply #52 on: August 24, 2019, 07:40:53 pm »
Make up a hard drying natural varnish mixture  and draw it into the wood   Will it be disqualified if you use a vacuum or pressure chamber?

I'd try any way I can to get it in there, But I dont have the aforementioned.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline Weylin

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Re: New heat treating method??
« Reply #53 on: August 24, 2019, 08:18:33 pm »
The saddest part is that his bows are nice enough without exaggerating. They look like great bows with nice profiles, absolutely respectable on their own merits. Since i’ve been hanging around here it’s obvious the most impressive bowyers are some of the least selfish with their ideas. Badger, if you talked like this guy it would set bowmaking back a decade and Marc wouldn’t be the King of heat treating without an entire kingdom of bowyers he taught to heat treat. Imitation is flattery and this guy treats it like stealing. Now he’s alone with his ideas and no better a bowyer for it

This kinda sums it up for me. This approach just doesn't seem to jive well with the openness of the bowyer community. I don't have a problem with people making an honest living off of primitive archery (I am), selling bows, teaching classes, writing books, youtube channels, etc, that feels all par for the course. For some reason the way they are promoting this video just kinda sticks in my craw a little. Something super secret that has never been done before, only way to know is to buy this DVD...  ::) ::) Maybe I'm splitting hairs or being hypocritical, I don't know. It just doesn't seem to take into account how we generally share information with each other. I feel like someone is going to watch the DVD and then, (if it's actually interesting), we will discuss the details of it in the open like we do everything else. Doesn't seem like the best marketing strategy.  ;D Oh well, I'm not holding my breath. I'm mildly interested to see how the whole thing will play out.

Offline Marc St Louis

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Re: New heat treating method??
« Reply #54 on: August 24, 2019, 08:42:02 pm »
This malming process does sound a bit like what I did/do while heat-treating.  What I started doing many years ago was to apply conifer resin, usually Spruce or Pine, to the wood at the end of each section of tempered wood while it was still smoking hot.  The resin would turn liquid and get drawn into the wood as it cooled, the amount of smoke produced was substantial and my wife would say I smell like a wood fire coming into the house  (=).  From observation I could tell that the resin was being drawn into the wood some 1/8" or more.  It's debatable as to whether this made the wood stronger but I would think it added some moisture resistance.  I don't remember exactly but it seems to me I did mention this in my section of the TBB 4
Home of heat-treating, Corbeil, On.  Canada

Marc@Ironwoodbowyer.com

Offline sleek

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Re: New heat treating method??
« Reply #55 on: August 24, 2019, 08:50:19 pm »
This malming process does sound a bit like what I did/do while heat-treating.  What I started doing many years ago was to apply conifer resin, usually Spruce or Pine, to the wood at the end of each section of tempered wood while it was still smoking hot.  The resin would turn liquid and get drawn into the wood as it cooled, the amount of smoke produced was substantial and my wife would say I smell like a wood fire coming into the house  (=).  From observation I could tell that the resin was being drawn into the wood some 1/8" or more.  It's debatable as to whether this made the wood stronger but I would think it added some moisture resistance.  I don't remember exactly but it seems to me I did mention this in my section of the TBB 4

When I get my books from storage I will read it again, it's been a few years.
I'd be excited to learn more about this.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline PatM

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Re: New heat treating method??
« Reply #56 on: August 24, 2019, 09:05:21 pm »
Make up a hard drying natural varnish mixture  and draw it into the wood   Will it be disqualified if you use a vacuum or pressure chamber?

I'd try any way I can to get it in there, But I dont have the aforementioned.

 Not hard to throw one together out of  commonly available parts

Offline scp

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Re: New heat treating method??
« Reply #57 on: August 24, 2019, 11:10:53 pm »
Using a vacuum chamber would be going way too far away from "primitive" bow making. I already have some qualms about using modern glues and finishes, especially two part epoxy. I justify the occasional use of them by distinguishing "primitive" procedures like applying varnish with brush from "modern" procedures like building laminated bows, with or without fiberglass. For me, "primitive" bows need to be made using natural materials using just hand tools. If not, any "modern" materials or procedures should be able to be duplicated using just "primitive" materials or procedures, at least in theory.

Offline sleek

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Re: New heat treating method??
« Reply #58 on: August 24, 2019, 11:25:24 pm »
Using a vacuum chamber would be going way too far away from "primitive" bow making. I already have some qualms about using modern glues and finishes, especially two part epoxy. I justify the occasional use of them by distinguishing "primitive" procedures like applying varnish with brush from "modern" procedures like building laminated bows, with or without fiberglass. For me, "primitive" bows need to be made using natural materials using just hand tools. If not, any "modern" materials or procedures should be able to be duplicated using just "primitive" materials or procedures, at least in theory.

No arguments from me there, but I still wanna know what can be done.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

Offline kbear

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Re: New heat treating method??
« Reply #59 on: August 25, 2019, 03:07:33 am »
Using a vacuum chamber would be going way too far away from "primitive" bow making. I already have some qualms about using modern glues and finishes, especially two part epoxy. I justify the occasional use of them by distinguishing "primitive" procedures like applying varnish with brush from "modern" procedures like building laminated bows, with or without fiberglass. For me, "primitive" bows need to be made using natural materials using just hand tools. If not, any "modern" materials or procedures should be able to be duplicated using just "primitive" materials or procedures, at least in theory.

I agree with this totally. It is one thing to brush on some pine resin while heat treating; it's completely another to use modern synthetic resins and a vacuum chamber. Not interested, thanks!

Shoot, I've only just convinced myself it's okay to use Dacron for strings!