Monday, October 26, 2009

Making A New Turning Saw - Part I


My "prototype" turning saw finally died. It was a quick and dirty project that was never intended to last. The original idea was to work out the bugs in the design, and then move on and make/use a nicer saw. It didn't end up that way. In fact the prototype was superior, and was my turning saw of choice over the years while the "nicer" saw hung on the wall.

Here's a shot of the DOA saw:


The epoxy that held the brass pin in the handle finally let go. I could just fix it, but as good as this little saw was (way better than you might guess from looking at it) I've been wanting to build that nicer saw that really works too. I though this was probably the time.

The new saw will be made of oak. I still have some left from the broken library chair episode. After making some cardboard templates, I traced the design onto the stock. I decided to make the handle convex where my hand will hold it, much like a panel saw handle, rather than the more standard concave bowsaw handle. I'm not sure if this will end up being a good idea or a bad idea. I'll know soon enough.


I prefer to do the mortising while the stock is still square. The setup is easy with the holdfasts. The big (giant!) mortise chisel and mallet do the grunt work and the smaller chisel is for cleaning out the chips and flattening the bottom:


The mortising sequence - start in the middle and work to one end (not quite to the layout line):


Back to the middle and work the other way:


Continue until the mortise is deep enough, then clean up the ends:


After laying out the tenons with the same gauge setting used for the mortises, I cut just outside the lines with a backsaw and trimmed with a shoulder plane to a snug fit.


Here's the saw so far - looking very chunky in its unshaped form:


In Part II I will shape the frame parts, make the blade assembly and create the tensioning system. After that, I'll try it out.

If history repeats itself, I'll be regluing the prototype in Part III.


9 comments:

  1. Hi Dan,
    Looking forward to the evolution of this little saw. But I finally have to come clean about my ignorance. What is a turning saw and how is it (normally) used?
    Thanks!
    Jeff

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  2. Ha, the old saw actually looks pretty cute. It's funny how minimal shaping on handles can go a long way.

    I like how you're using those leftovers.

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  3. Good timing Dan, recall you encouraging me to make one of these, following with interest, rick

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  4. Jeff - Others might see things differently, but for me a turning saw is one type of bowsaw, which in turn is just one category of frame saw. Salaman defines frame saws as those “in which a narrow blade, known as a web, is stretched between tow points of attachment within a wood or metal frame.” Some, like the frame saw I use for resawing, stretch the blade with a screw device while it is held within a ridged frame. Those I call bowsaws, use a tensioning device to draw the ends of two arms of a frame together, and those arms, levering off of a center stretcher, tension the blade held between the far ends of the arms. Some of these bowsaws, which I would call bucksaws, use a turn-buckle and threaded rod to provide the tension. Others, which I call turning saws, tend to be smaller, use twisted twine and a toggle stick to create the tension and, importantly, have blades which can be turned to allow cutting at any angle. Whew!

    Of course, just to keep things interesting, I tend to use the terms somewhat loosely – referring to a turning saw as a bowsaw, and/or frame saw.

    I guess it might have been simpler, and more useful, to just say that a turning saw functions like a giant coping saw and is very useful for cutting curves of all kinds. They are the Neanderthal equivalent of a band saw. I’ve seen Roy Underhill use one with a cranked, or twisted, blade that can turn a 90 degree corner.

    Brian – Thanks. Yeah, I agree, there is something kind of charming about the old saw’s understated nature. I probably will repair it eventually, just out of gratitude to the little workhorse.

    Rick – Well, hopefully I don’t bungle this job then. It really is easy to make a good saw, but having publicly stated that, this one will probably bite!

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  5. Dan, thanks for that very complete answer. I realize, now, that the saw can "turn" to create a curved kerf. Makes sense. Thanks for being so generous with your time to give me such a complete answer. Looking forward to upcoming parts.
    ~Jeff

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  6. Jeff - You're welcome. Thank you for reading and commenting!

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  7. Dan,

    I've got a question...

    I'm burning Wood for the winter, and I've seen some really nice Chopped up Oak some of it's got a Red Tint to it assuming it's Red Oak.

    Some are pretty heafty Pieces, just the standard fireplace size.

    I tried cutting one of them on my Bandsaw which is a craftsman but kinda smaller one, i was gonna make Kinalin outta it to help start fires.

    But anyway, Since I seen some Good pieces, and i generaly work on Smaller projects with my Scrollsaw, And these chunks won't fit threw my bandsaw to resaw, what can I do or how can I Slab these up?

    I don't have any Hand tools at all, Not yet anyway, been looking at the antique Mall and found some Planes, but anyway, I'd like to cut these up, but they are too big for the table saw and band saw.

    I don't have a Hand saw either, well I do, but it's to my miter box and it has a bridge I call it over the top that keeps you from sawing into the minter box, which won't go all the way threw.

    The Project is coming along great thou, Nice work and use of Scraps.

    Handi

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  8. Handi - One idea might be to try splitting the oak into slabs or at least manageable size pieces for the band saw. If the grain is straight, the oak should split fairly straight with just an axe, or hatchet and a wedge if needed. Of course, after that you would need to flatten it, which I would do with a hand plane or drawknife, but you might be able to use a power planer. I also seem to remember seeing (back in my power tool days) some kind of sled type fixture that allowed for resawing logs on the table saw.

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  9. Dan,

    Well, I have a Planer, but that only works if you have 1 side Flat, Unless you use a Jig that helps to flaten it kinda.

    Then that only works so far, I was thinking of just splitting then Planing with a Hand Plane of some sort, the wood is really too small to use on anything else except for scroll work or possiblely some smaller projects.

    That's the Idea behind it thou, I just didn't know if you had any Thoughts on it that would work for someone with limited Handtools, I'm still Looking into some Hand Planes, I want the best of both worlds, more on the Hand tool side, but have the ability of bith if needed.

    And since The wood is smaller, I thougth it would be a great Opportunity to try and Split or board up by Hand, i tried my Bandsaw on s Slap and I pulled my Blade off lol, and had a time getting it outta the wood, was to wet i think.

    So I'm wanting to invest in some Hand tools, I think I'm going to try and find a Resaw Saw, and get me a few planes, Got a few Antique stores around here that may have some tools like that.

    Thanks for the Input!

    Handi

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