Something that Ironsides said on the HäT Forum in a post about leather equipment rang a distant bell. He mentioned "chrome leather", which I now know to be this:
Chrome-tanned leather, invented in 1858, is tanned using chromium sulphate and other salts of chromium. It is more supple and pliable than vegetable-tanned leather, and does not discolor or lose shape as drastically in water as vegetable-tanned. It is also known as wet-blue for its color derived from the chromium.
I have remembered where I've read it before. The tracks on the Lefebvre Tractor were made of it.
-- Edited by James H on Tuesday 5th of January 2010 02:24:28 PM
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
Hi James, wheres your source from... if you dont mind me asking, seems a very poor material for tracks although leather belting for industrial machinery was common... The main advantage with chrome tanned leather is the speed at which it can be produced, weeks instead of mounths(it actually takes a day in a modern tannery for the process but requires additional treatment)....
The same thought occurred to me, but I definitely read it somewhere, in French. I remember having to look up cuir chrome and was surprised to see what it means. Can't find it on t'internet, so maybe it's in Ramspacher's book. I shall have a look. Since there's a foot of snow outside I've got plenty of time.
Maybe the blade things were riveted on. We know Tritton & co had a try with Balata Belting. Lefebvre is described by several sources as the only man in pre-War France who knew anything at all about tracked vehicles.
__________________
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
Found it. It's a footnote in François Vauvillier's article in GBM 87 on the Renault Porteur. Lefebvre's first name was Edmond. The vehicle had "steel plates fitted to a chromed leather track". About 10 were sold commercially before the War.
Maybe François can confirm.
__________________
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
You're quite right. The drive chain was like an outsize bicycle chain, and the leather was there to protect it from dirt and grit. Well done, that man.
Now, when Estienne went to see General Janin in December 1915 he was, according to Ramspacher, accompanied by a Reserve Captain Lefebvre from the 6th Artillery Regiment. Is that the same man? It would make sense if it were, but I don't know for certain.
__________________
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
Oh, I see, the tension is carried by a roller chain and the leather is for floatation. Probably cheap, pliable and light. Just can't imagine it lasting all that long being dragged through the mud and such, being exposed to molds and other things that like to eat leather. Maybe the Chromium process helps?
Yep. I've had another look at François's description, to make sure. He says it was ŕ chenilles de cuir chromé ŕ palettes d'acier - "with tracks of chrome-cured leather with steel plates", so that appears to be a misunderstanding.
I suppose the leather would have spread the weight to a small extent, but the patent says that its main purpose was to protect the chain.
BTW, Witold Lawrynowicz says that the Capitaine Lefebvre who accompanied Estienne was the man who produced the tractor, although he says L was with the 22nd Artillery Regiment.
-- Edited by James H on Wednesday 6th of January 2010 06:33:19 PM
__________________
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
Hi James your welcome, no one was more suprised then me..... thats the only one on google patents though, anything else is not in his name...
On Crome Tanned leather.... personally I hate the stuff for handworking its awfull... It does however have certain properties which would make it better for this application.... resistance to water, rot and stretching..... Not what I would call it the ideal material, a reinforced rubber sheet may well have been better but this was probarbly what was easily available and cheap...Compared with other types of leather, Oak tanned leather for example takes a very long time to tan, would you believe it can take up to 18 mounths!(and time is money) and is a dirty, messy, stinky process......
As no one else seems to have taken this idea seriously I guess ít was'nt that successfull with possibly this one exception....
You know I've just realised this is a Wheel/Track device as opposed to a half track proper, so maybe this is what inspired all those odditys during the 20/30s was this the First?...... looking again at the pics I guess the tracks wouldnt take any real wieght at all most would be on the rear wheels, with the plates producing traction by digging in the ground... which would account for the leather only being a guard to protect the chain.... Interesting concept....
Cheers
-- Edited by Ironsides on Wednesday 6th of January 2010 11:41:51 PM
I hadn't realised the Lefebvre had been brought up by Tim R. His description is from Ellis & Bishop. Some say it was on a Schneider tractor chassis, others that it was on a lorry chassis. Perhaps both are right - have you noticed that there is a four-wheeled version and a tricycle version? Pics below, stolen from Tim. Photos bear this out.
M. Netzel's idea looks as if was fitted to a Mack Bulldog.
I think Lefebvre is a reasonably common French name, so it might be a coincidence, but if talk of tracked vehicles was in the air it's not unlikely that Estienne contacted L (or vice versa). They were both artillery officers, too. It would be nice to get some confirmation on that.
One thing is undeniable. It would come in very handy for getting to Sainsbury's in the current conditions
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.
Hi James I think there are at least 3 different vehicles there, two tricycles and a four wheeler.... the only thing that seems to remain more or less the same is the tracks, so perhaps he was trying to demonstrate its usefullness on different Vehicles..