Tools from Japan blog.

Hi all,

Seems I am on a roll here, putting out post at a record (for this year) pace…

On the last post I put up, one of the comments was this;

Hi, Nice blog, some interesting reading. I need some help in using a Japanese style saw for ripping hardwood. I have the double edged style made by Vaughn. I’m having trouble keeping the cut from wandering off my marked line. I am usually cutting smaller pieces (18″ to 24″ max) and secure them vertically in a vise. Should I try the traditional low bench Japanese craftsmen use? If you could point me to a web site, blog, book or just your advise, that would be great.

Thanks for all the work you put into the blog.

Tom Goodman
Bailey, NC

Firstly, I will tell you this.

I am not an expert when it comes to Japanese tools. Some might argue that, but an expert to me is one who can pick up any tool and do efficient, profitable work with that tool.

I cannot admit to be able to do that. Not with all of them anyway…

(However, hand me a pair of pliers and a screwdriver, and I could claim that title.)

I must also admit that I am probably what you might think of as lazy. When I need to rip a lot of wood, I switch on either the bandsaw or tablesaw. If those two won’t work, I reach for the circular saw, and finally handsaws.

Of those handsaws I have two choices when it comes to ripping, an old Disston ‘Warranted Superior’ rip and a Z Saw 250mm rip kataba.

Call it lazy if you must, I call it ‘getting the job done’. The wood doesn’t care, and neither do I. Just get the stuff cut and move on.

Having said that, I am also afflicted with a peculiar disease, that being someone who must be able to do it by hand as well as be able to flick a switch. I find that when you know how to do something by hand, it is of great help when you switch on the power tools. You have a better idea of what’s going on when it’s all working right, and how to fix it when it’s all going wrong. You also have a plan b for when it’s really going wrong, and a hand tool can and will dig you out of a big problem much easier and faster (most of the time) than throwing money and big machinery at it.

With that, here’s what I can suggest to you Tom.

Match the saw length to the job.

All that means is making sure that what you are cutting is not too big or small for the saw you are using. With Japanese saws, the effective pull stroke is much shorter than the push stroke available to Western saws. That is not to say that the same power is not available, but that Japanese saws are better tuned to where the power lies in the arms, body and legs of the human body.

With a Western saw, I find I get maybe 8-12″ of solid push, followed by another 6″ of moderately purposeful push and then another 6″ of simply following through. Out of that, only 12″ is doing much work, the rest is a lot of motion, not much work.

With a Japanese saw, again I find maybe 8-12″ of solid pull, and by that time the saw is out of length, and it’s time to return the saw to the starting position.

It also means that with a Japanese saw you need to really match the thickness of what you are cutting to saw length. Too short a saw, you are working away with a short, inefficient pull all the time. Too long a saw, and you tend to drag it through the full length of the blade, with the last little bit being just for appearances.

Yes, the extra stroke without power behind it does clear the kerf, but at that last little bit, you are probably over extending yourself which can lead to mistakes and loss of control. Over working also tires your muscles faster, making the problem worse.

A simple rule I use (which may or may not be correct) is to use @ 250mm of rip saw for the narrower thickness of a 2×4. 300mm will do the broader thickness of a 2×4. In hardwood, reduce the thickness possible by as much as you feel the wood is harder than common construction softwood. Something like maple, I’d drop it to maybe half. Beech, 2/3 of a 2×4. Cherry, 3/4 or so.

It’s my own rule of thumb, and don’t forget I will gladly switch on the bandsaw without provocation.

Match the saw type to the job.

You mentioned that you are using a 2 sided ‘ryoba’ type saw. These saws are great for short rips in joinery, and even trimming the occasional thin panel to width. What they are not so great for is hacking down great lengths of thick material. Just the wrong tool for the job.

The problem is the cross cut teeth on the other side.

In order for the saw to cut, it needs for it’s teeth to cut a wider ‘trench’ than the rest of the blade. This is the tooth ’set’, and all saws need it to cut more than an inch or so, cross or rip cut.

When you bury your two sided saw in the cut, the teeth will make a trench more than wide enough to let the body of saw pass through unimpeded, until you get deep enough that the back teeth are also into the cut. At this point, you have a saw with no set at all.

Normally a saw with no set will bind in the cut and saw no further. With a two sided ryoba, the amount of resistance is very small since the only points touching the sides of your wood trench are those on the back side’s teeth. A very small area, and you probably don’t even notice it.

But the saw notices it.

It has gone from making a trench that gives it room to move and will allow you to steer it a little in the cut, to having no room to wiggle and there is no way you can steer it in the cut. It is locked into whatever path you have already made, and if that path is not dead true and on the line, it’s going to wander no matter what you do.

This is probably the biggest cause of your problems, and while it can be fixed there is no going back and the saw’s functionality will be permanently changed.

If you take a sharpening stone and remove some of the set on the cross cut teeth, you will give the saw a little room to move when it is ripping. Not much, but it may be enough. Once you do this, you cannot cross cut any deeper than 75% of the saws width between the rows of teeth. Any deeper, and those big, aggressive rip teeth are going to bind in the cut, and as they stick out further than the trench is wide, the saw will bind and you will notice it. It may bind enough that it will not go through, at which point you will probably bend or break the saw.

There is heaps out there about saws, the kerf they cut and all manner of related things. Every little difference in a saws teeth affect several other factors, the tooth set more than most. It’s worth reading as much as you can about set, and also get out there with some saws of different types (and different set) and see what is different about the saws and how differently they cut. I won’t expand on it here, but it is worthwhile knowing about, for both power and hand sawing.

Concentrate on your cut, nothing else.

This really doesn’t need any explanation. Japanese saws with their finer kerf (trench width) and thinner saw plates (steel they are made from) require more attention to keep them running straight and true. They are a finer instrument than their Western brethren, and need to be treated as such.

When you are learning how to use a Japanese saw, there are a few points that may help.

#1, get the cut started straight and true.

Fail to do this, and your cut will never be any good. Unlike many Western saws that can be ’steered’ in the cut with gentle persuasion or flat out force, many Japanese saws cannot be easily directed once they are started. This is partly their shape, their delicacy and the way in which they are used. You can try to guide the in-progress cut, but it will get ugly very quickly more often than not.

#2, you are just a motor.

Once the cut is started, all you really need to do is simply pull the saw through, then push it back. Do not apply pressure to the cut, just keep the saw moving at a pace you are comfortable with. If you feel the need to push the saw through, it’s blunt and the blade needs either sharpening or replacing.

#3, don’t get complacent.

You may only be a ‘motor’, but think about a motor. It does what it is told in a predictable, stable manner. You need to do the same. That means focus on keeping the stroke straight and consistent. Keep the cut in a position where you are comfortable with it, not too high, not too low. No twisting or bending. Just keep the saw following a nice, straight and predictable path.

#4, if things go wrong, stop!

If, contrary to your best intentions the cut goes bad, stop cutting. Trying to fix things will most likely make it worse. One thing I do find is that once a cut does go bad, you can often see where the problem started and just as often, can re-start the cut there. Doing this opens up the kerf/trench a little and allows you some room to move.

#5, practise, practise, practise!

Learning on a beautiful chunk of wood with a wonderful new tool is silly at best. For sure, use good tools but get some practise time with wood that you don’t mind turning to firewood first. You wouldn’t start out learning how to make dovetailed drawers with bird-eye maple, because it’s going to end in tears, no matter what you do. Grab a 2×4 and slice that thing up. By the time it’s more kerf than wood, you should have the experience to attack almost anything.

The final, and possibly most important part is…

Use a good saw…

It’s no secret that there is a commercial store now attached to this here blog, and in it I get to decide what goes in and what does not. I won’t sell any tool I cannot believe in, and most of them I either own or have used so I know what they are going to do before you get them.

I won’t sell a tool that won’t ‘just plain work’, and that goes especially for saws.

It’s real easy to produce a Japanese saw with a replaceable blade. First, you contact a company that makes the machines (like Nakaya, makers of the ‘Eaks’ saws in the store and made the machines Stanley uses to make their saws), order one, set it up then pump out as many saws as the machine can make.

It’s moderately easy to make a reasonable saw, I should know, I have a choice of dozens of saw brands, no two made in the same place and no two exactly the same. Most of them are at least reasonable, some are good and a few are great.

It’s real difficult to make a ‘good’ saw.

And to perform a long rip with a ryoba in any wood, you really do need a good saw. If there is any question to it, it won’t work so well.

And I hate to tell you this, but I’d bet that the Vaughn saw is not a ‘good’ one. Decent? Maybe, but probably not good.

In the hands of a skilled Japanese saw user, it may be able to make a nice, long, straight rip in hardwood. But you are asking a lot of a saw that was never really intended to do that.

The thing is that a good or even great saw makes this demanding operation easier with a better chance of success.

But really, this is an operation for a rip saw. In Japanese, a tatebiki-nokogiri which translates as ‘vertical-cut saw’, in regards to how the tree grows. In simple terms, a single sided kataba style saw with rip teeth.

By losing the teeth on the back of the blade, half the troubles are solved instantly. You still need to pay attention, as the saw will not cut perfectly if your skills are not up to the task. I know, when I was cutting my teeth with Japanese saws, I could not saw more than 12″ straight when ripping hardwood, even with a rip specific saw. But the ‘right’ saw makes the task much more possible than the wrong saw.

And I’ll be honest here, the ‘right’ Japanese saw for the job is going to be expensive. What you really want is a proper, hardwood specific rip saw designed for long ripping operations. And they are rare, really rare. So difficult to find that if you want one, it’s a case of special order only, there are none on the shelf.

I have one, but it is set up for softwood. It’s a monster of a saw, and I am not good enough with it yet to be proficient. However if I wanted to rip down a piece of hardwood no thicker than 1″, it would chew it up faster than any saw I can imagine, if I was strong enough to work it.

But seriously, look up some plans for a frame saw. About the best tool for ripping by hand that is available. The thin, narrow blade is easy to drive and supremely steerable in the cut, because the blade is under tension it won’t buckle and you don’t need to worry about that, reducing stress. They are simple to make (cheap!) and work so well, I am surprised that Japanese wood workers don’t use them.

Well, actually they did, but you don’t see them very often any more…

You can get it done with a simple ryoba, but if I was in that situation, I’d be looking for a better tool to get the job done with.

I hope that helps you out Tom, although it doesn’t actually solve your dilemma with regards to the saw you have. Don’t give up, but do look for another way to get the job done. Your Vaughn ryoba may be capable of ripping hardwoods successfully, but it’s going to take a lot of time, effort and practise to get there. If you put in the effort however, you should be able to pick up any saw and cut like a professional.

Thanks for reading, and I’ll try to keep up with this furious rate of posting if I can.

Stu.

P.S: I almost forgot! (Sorry Phillip!)

I did look up where Bailey, NC is in google maps. Regrettably too far away for this little additional bit of info to be of much use.

In the east area of North Carolina, there is a Japanese wood working club known as the ‘Piedmont Japanese Carpentry Club‘, and there they may be able to give you some first hand advice on getting your rip cuts straighter and more effective.

They will also have a tatebiki-nokogiri there if you would like to try it.

I know it’s a long way from where you are Tom, but if you happen to be in the area, it would most certainly be worth the effort to drop in and say hello.

Bring wood and tools.

Stu.

This entry was posted on Monday, March 15th, 2010 at 10:18 pm and is filed under Tools.. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.