Heat Treating Wood...Humble Pie.

Based on the contents of H/Umble pie ..Gravy

http://www.phrases.org.uk/bulletin_board/1/messages/2689.html

Which one is just a matter of personal taste.

Just be sure you warm it up thoroughly.

Wow, I thought I did weird things.

It seems like you are saying that it worked. I don't quite speak Queen's English so I don't follow the " gravy or custard with Humble Pie" bit after you seem to claim success. There was one thing that I thought of while reading this. One of the educational channels will from time to time show specials on old musical instruments. The "old masters" had knowledge of grain, wood age, sap, heat treating, repetitive stress, etc. This knowledge is mostly lost in the modern world.

If you want to master the art of war you need to master the art of making sweet music during times of peace - - - Chinese fortune cookie from lunch last week.

A clear case of "cat's always land on their feet".

I doubt that Kyzine chap is going to raise the subject of a small paw banging loudly accompanied by raucous mewing sounding remarkably like "male bovine waste product", or that ER will flail her fav pussy for "However I just bought a temperature controlled heatgun which allowed a slow controlled heating"

Cat of the Antarctic Free, I'd say.

I doubt that ... ER will flail her fav pussy

Only if said puddy tat gives lessons....

I just shot the bow through my chronometer and it's over 100mph.
That's the fastest per pound of draw weight of any bow I've made.

I did a lot of of web searching to try to find technical data on this topic, but came back with very little except an article about structural timber being treated at 200C.(Which is why I started heating at 200)
I don't s'pose this stuff is of much general interest, but I thought it compares and contrasts with Milo's excellent articles on the properties of steel.
It appears we don't really know that much about the properties of wood.
Del
(A websearch for 'Ash Wood Properties', came back with a load of estate agents blurb of course)

Dare I suggest 'compound' and recurve are actually similar acceleration concepts?

Maybe look at that leverage/catenary/limb mass, with how you build and string a recurve?

I've built all sorts of bow including Asiatic styles, I'm not after speed per se.
My interest is in self bows mostly, that's bows made from a simple piece of wood.
Check out my website, or my other post on CR4, the Chinese repeating crossbow is fun.
Compounds are fine from an engineering viewpoint and impressively fast, but they don't float my boat, unless maybe they are handmade by the user.
It's the craft thing to me the mix of art, engineering and good old hand eye skill.

Del

You might have already read this ...
http://www.archery-interchange.net/forum/traditional-archery-discussion-q/14230-heat-treating-ash-bows.html

Thanks, I'm often on that site, but contrived to miss that thread.
Cheers for the heads up
Del
(I link to that guy's website from mine and always read his stuff, so I dunno how I missed his post)

Great blog and interesting posts.....I see no need for Umble Pie in the slightest!!!

(Though I bet it tasted great! Deer innards one I mean!!)

Kep 'em coming Dell.......

Although I can't give a direct answer to your question, I know that in addition to about 30% water that eventually equilibrates as it is seasoned, wood also contains unique temperature sensitive resins that affect its final properties. I once watched a park ranger trying to drill a hole in a wood panel to hang a shaving mirror. The drill got red hot and melted. Further inquiry revealed that the wood was Dade County Pine, an extinct species, that lumbers like a common pine tree. After about 60 days of seasoning, the internal resins polymerize, leaving the pine wood as hard as a piece of petrified wood (stone). Some day you might want to consider making a bow from black palm wood. That material has properties that rival some metals.

Here's a couple of pics, the first shows how the heat treating accentuates the grain.

Seconds shows it on the tiller at full draw.


Del

You got the gravy and you deserve it, for following through, making it work, developing the technique that is effective... kudos.

If you can teach yourself without a teacher by perseverance, well that's how things got discovered in the first place...

Cheers.
It just seemed to me that it made more sense to spend my money on the heat gun rather than the Traditional Bowyers Bible vol 4 which apparently has a chapter heat treating bows.
I'd gleaned the basics alread, my initial tests didn't work 'cos I heated too hot too quick and didn't allow time for the wood to rehydrate.
Books are great, but at some point you just have to do it yourself. (That doesn't apply to crime and horror fiction of course, put's chainsaw down and shambles off)
Del

Del,

do you think that the English longbow was also "cooked" to improve its qualities?

It was apparently the medieval "secret weapon" according to history, so to say....

Maybe the English "secret" of the "weapon" was being able tp pare the wood down to a great lightness and speed and got the stiffness from careful heating/curing....

I wonder if any Longbows have survived in museums and the like and whether or not you could observe to see if any have obvious graining from the treatment. (and whether you can still see that on a 500+ year old piece of wood or not!)......or any other test that would show the chemical changes (or not) from heating....

It would be nice to hear your opinion/thoughts on the subject, thanks in advance.

I believe that some cases of 'new' long bows were recovered from the 'Mary Rose'.

As I understand, prior to this discovery the method of making the long bows had been lost, however this discovery showed that the long bows were cut from the Yew tree in such a way that they contained both heartwood and sapwood giving them strength and resilience. As to heat treating, I do not know.

Bill

Yes the Mary Rose bows were analysed and tested, but no the 'secret' of using heart & sap wood combined wasn't lost.
The main thing learned from the Mary Rose bows is the high draw weight of these bows although there is still much argument/dicussion/controversy.
Best estimates put them in the range 100-180 pounds draw weight.
There are guys in the UK drawing these weights today so it's perfectly feasible (I can puul 90lb and I'm an old git who hasn't had a lifetimes training) To distinguish these bows from the Victorial style of longbow they are often refered to as warbows these days. My Yew longbows fall somewhere between the two, I like a warbow style but at a manageable draw weight.
The warbow would bend 'full compass' though it's whole length, whereas the Victorian target bows tended to have a stiffer handle section.
Del

Andy that's a good Q and something I might try (only on the belly of the bow).
I don't think they would have been cooked in those days, we don't really have any evidence for it and I'd guess it would be an extra unecessary step in the manufacture.
That's the beauty of Yew it is strong and can take huge forces without breaking. Supply of decent staves was a problem, but that was solved by making countries like Italy and prob Spain ship in staves as a sort of import duty on any other goods.
Heat treatmen may be useful for me to toughen up Yew which is maybe not as tight grained or stiff as I'd like.

Del