Hello all, At first glance you may think that this subject is not very scintillating as Tyzack et al saws, whilst not ten-a-penny yet, are definitely not uncommon. But this saw is a little different. I have, apart from the more common wood saws in my collection, a salt saw; a couple of examples of butcher's saws; and a putative (although not proven) tailor's saw. This, however is billed as a saw for Kitchen use, although what a saw would be used for in the kitchen is beyond me unless it is a variant on the notion of a butcher's saw. Or possibly a saw for bread. There is a Kitchen saw in BSSM, although I have never seen one before. Fred
Hi Fred, I like the lower horns on the handle, it really makes me wonder what they were cutting up with that? Legs of Mutton? Pumpkins? Cinnamon sticks?? How long is it, 12" or 14"? Regards Mari
Hi Mari, The saw is 12 inches long. They perhaps called it a kitchen saw because the blade quality was so poor that any other usage would quickly degrade it. I don't have a proper micrometer an so I cannot measure the thickness of the blade properly, but it is awfully flexible. Fred
Interesting that you mention that the blade is poor... do you mean soft, or lacking spring? Maybe it got a bit hot and lost its tempering? Also, to keep costs down it may not have been hammer finished? Is it an early form of (softer) stainless steel? (sorry, a lot of questions). I say this because Tyzack saws (in all the iterations), while not being Rolls-Royce quality are normally a decent product and make good users. The handle suggests that it isn't a 6th grade product line.
The blade is flexible in that it has spring to it, but it is quite easy to flex, much more so than a couple of other saws of the same blade length that I picked up at random. I have an electronic caliper and this measures the thickness of the blade (at the rear just above the toothline) as 0.019.5 or 0.020 inches. The less flexible saws have a plate thickness of 0.025 and 0.028 respectively. Again, this is not a micrometer and so take the measurements with a pinch of salt You are right about the handle, the thickness is just under 1 inch and which to my mind makes it a decent thickness for a quality saw. I have just tried my Cheap Chinese Chisel test on it (trying to scratch the blade with my standard cheap Chinese chisel kept specifically for this purpose) and the chisel, whilst not bouncing off the blade like a couple of Groves saws that I have tried it on, does not make much of an impression on it at all and so the blade must be reasonably hard. Perhaps I was wrong on blade quality and that it is just a little on the thin side. Fred
Apologies Fred if the following discourse gets a bit technical but it is an issue I struggle with. All that follows is in imperial measurements because the saws we deal with were made in that system and it makes it easier for us to relate to. I'm also talking western backsaws working in a forward stroke. If I remember some basic building maths, the difference in strength between two bearers is a cube of the difference in thickness, thus small thickness variations can have a large effect. Similarly, for rigidity (K), K = (cross sectional area) x (elastic modulus) divided by length... so what does this mean for the average saw plate you ask? Well, there is a modern trend for really thin plates on backsaws such as 15 or 18 thou, and I've even seen decent-sized (16" from memory) tenon saws made with thin plates (which I'd ascribe as <25 thou). Now, how many old saws do you see in thin gauges... very few I'd reckon and I bet those were pretty munged up. I'd bet they were small, short saws (say <9" dovetail) and had fine toothings, maybe something around 18 points? The reality is that thin plate saws have a lot of issues that really defeat their use in actually sawing wood. For starters, they bend and there is nothing you can do about it as the physics dictates that they must. The thin plates also struggle to cope with the pressure created by teeth so small teeth are a must, and the lack of rigidity dictates a short working length. Basically, flexible saws have tracking problems. In addition, people forget that the friction resulting from cutting also heats up the plate and a thin plate is a small heat sink. A plate that heats up warps and again the saw won't track properly. This causes the following workshop scenario; gee this saw is getting tight halfway though the cut, I'll just push a bit harder...oh, it stuck a bit, damn, there's a kink in it now. To illustrate this I own a modern 10" 15 thou gents saw from a leading maker and it won't cut cheese. I also have a 9" 20 thou dovetail saw from the same maker which is a brilliant saw in dry hardwoods less than 3/4". The heavier spine, shorter length, thicker plate and finer teeth on the latter make it an excellent tool - the former saw is rendered useless by the thin plate. Similarly I can't see how a thin plate tenon saw could possibly fulfil its role of cutting deep, STRAIGHT tenon cheeks. I think that people are getting sucked into purchasing thin plate saws believing that finer kerf will improve their work- as discussed above I believe that the thin plate saws people are buying is actually making woodworking difficult. A main reason for using a handsaw is accuracy and I can't see how thin plate saws promote this.
Hi Fred, I'm loving your "Cheap Chinese Chisel Test", that is the best thing I've heard in ages... And Dusty, great points about some tenon plates being too thin- theres obviously a limit to length vs thickness & I guess if people want a 16" tenon 15thou thick they may want it to be a pull tenon saw! Mari
Hi Dusty and Mari, Please do not apologise for posts like that Dusty, I find it very edifying and informative. My Cheap Chinese Chisel test, Mari is not a new idea but I coined the term some years ago on this site when, from my increasingly unreliable memory, I tested the hardness of the saw plate of a Groves by trying to scratch it with one of my C C (wood) Chisels. It just slipped over the top of it and left no mark at all. Now, I don't know if any of you are cheap Chinese chisel aficionados but my experience of them is quite extensive as I tend to abuse (in one way or another) most of the tools that I use and so I am reluctant to buy quality ones. My experience of CCCs is that they come in two sorts, the ones that bend and the ones that shatter bits off the edge as soon as you look at them. My standard saw testing chisel is one of the ones that shatter, and thus, I assume is quite hard. And there is some (and I say some advisedly) validity to it as I have had results on saw blades ranging from gouges being made in the plate to the above Groves that was not marked at all. I append the photo of the marks to the Kitchen saw plate below. Please don't take this too seriously, it is a bit of fun but with a modicum of informal practical application. Fred
Fred, I'm all for practical tools of investigation and you have stumbled across a powerful piece of real world science with what you call the 'cheap chinese chisel test' - the basis for a number of sciences, such as mineralogy, where the relative differences in hardness are known as the Moh scale. This is based on everyday items and very useable. You can buy hardness sticks from engineering supply stores or alternatively I use a carbide awl for a scratch test akin to what you do. As you indicate you can quickly ascertain what saws are hard and what is rubbish... another way is to file them, and jointing is a good way to pick up uneven tempering along a plate. I also watch(use a lense) for a coarse steel grain (= low quality) or the formation of carbide impurities (very hard, often circular spots that resist corrosion) on very hard plates.
I was thinking a thin saw plate might be quite appropriate for cutting up meat and vegetables in the kitchen (but I've never tried that with my saws)
A v. interesting exchange by our scientists; well beyond me. In general terms a saw made for kitchen use (mine looks exactly like Fred's, dated at c1910) wouldn't have a very good blade, but the hardness of blades was dependent on the hardening and tempering stage of manufacture, and it could go wrong. I have a Groves saw which I have offered to two saw doctors, both of whom gave it back in disgust, saying it was "glass hard – haven't got a file that will touch it". Saws were put in bundles of 10-20 between heavy iron plates and plunged into hot whale oil (plus added resins etc: it's all in Holtzapffel's big encyclopaedia) and then put in a coke furnace to burn off the residues. Judging how much burning off was another crucial process, and I guess sometimes (Friday afternoons?) could go wrong, and some saws in the bundles could be differently affected. These were the kind of processes that made the quality of saws, and Sheffield tended to be able to do it consistently, if they wanted to for the price, just as, I suspect, Disston also could, with his insistence on standardisation. As for Tyzack quality, my understanding is that their saws were some of the best – kitchen ones excepted – and I've met professional woodworkers who used them in preference to anyone else's.
Simon, I've only dealt with one Tyzack saw marked "for kitchen use", a No. 24 or 24A I think it was. I found it identical to other Tyzack's I've filed. I'm extremely keen to know more about the tempering of saws. From what I've read the smell of burning whale oil is supposed to be indescribably foul. After the process you described above I've read that the saws were invariably warped and had to go through additional straightening work. Atkins (USA) claims that its saws were tempered using a patented "gas process", though I have no idea what that entails (perhaps they used an inert gas blanket to prevent oxide formation and carbon-robbing akin to modern TIG and MIG welding?). Some edge tools e.g. razor were tempered in a bath of molten lead- I'd hate to know what that did to the health of the workers tending the lead baths.
Mari has the advantage over me of actually having filed a saw. No one in their right mind would ever even ask me to try. I suspect that there was a huge amount of obfuscation by those in the metal industries about what they did, and short of talking to people about it (there are still a few left in Sheffield who have direct experience, including one man who does indeed confirm that hot whale oil smelled disgusting). My own "knowledge", which deserves more than inverted commas to indicate its superficiality, includes my reading somewhere that the tempering of steel was the process that gave it its quality.