Like to make a hand saw.

[Ray Gardiner]

First attempts at slitting a brass back, I got a 0.020" slitting saw blade off ebay and an arbor to suit.
After much consideration, I eventually went with this setup on the drill press.





Setup is **VERY** time consuming, I must have fiddled around for ages to get it tracking straight, and in the middle
of the back but now that I know it's going to work, I need to come up with a way make it more robust and easier to setup.

More Pictures here:-

http://www.backsaw.net/cpg/thumbnails.php?album=20

Regards
Ray

[Ray Gardiner]

Jeff,

This is the first saw I made, it was made from an 8" Crown gent's saw. I made it for Galootaclaus 2005, and gave it away as my gift. Haven't seen it since...

Hi Alan,

Unusual handle, how comfortable was it? Also what is that timber?

Regards
Ray

[Ray Gardiner]

Here's another one I made last year. This one I slotted the back, used a piece of 1095 spring steel, and the split-nuts were made by Johnny Kleso (a.k.a. rarebear). This one I still have and use. Will most likely end up giving it to my son.

Hi Alan,

I like the London pattern handle, how did you slot the back?

Regards
Ray

[Alan DuBoff]

Unusual handle, how comfortable was it? Also what is that timber?

Very comfortable, the recipient seemed happy with it, but it was designed so that your finger was held in position as it felt comfortable to saw. Yes, it was different, and that is what allows us to create things that may work better and why I do things like that. The same reason I feel bronze is a better allow to use, that inlays in the handles is something people would pay extra for, inlaid gems and/or stones such as abalone, mother of pearl, or herringbone being options that people would like, even at a price. Sure, some of the saw makers are putting out tons of saws and they function well, are quality tools, and the results speak for themselves. I'm not looking to have exactly the same saws produced 200 years ago in all cases, I want unique tools that I build.

Handle on that was made of maple burl.

I like the London pattern handle, how did you slot the back?

That one was done on a Grizzly mini-mill, using a fixture that a friend helped me make on a Bridgeport and a HAAS CNC. It was my first time to use a CNC, he was a great help. Not bad getting help from a local high school kid that is now studying robotics at WPI back in Mass... He is barely older than my son, and he's taught me a tremendous amount about working metal, as well as lining me up with a friend of his that sold me an old South Bend 9A (came out of the Levi Strauss factory in SF when they closed it down).

I have a Nichols horizontal mill now, and have slotted some bronze since.

Here's a video, if you care to see my mill.

[Alan DuBoff]

Ray,

Your slitting blade looks like it's one of the course tpi blades, I have some like that also, but found out that you need to cut at the right speed, and that might work better in your drill press. You need to calculate the cuts per second and/or rpms, to get the right about of cutting for the stock being cut. I have switched to finer tpi and it works better for me. I'm more careful about the blades I buy nowadays. My mill has much slower speeds than your drill press, not to mention the lack of stiffness on a drill press, but it will work as you have found out. I don't like wood fixtures, although Mike Wenzloff uses wood with HUGE success. He also uses a mini-mill which I believe to be a challenging machine without mods. Here's my mini-mill. Pretty simple initial setup using 1-2-3 blocks as the fixture with some table clamps, it worked, but this fixture was way better. Note how I ran into another problem on the mini-mill in the last picture, it required this modification to work around.

That blade is good for slitting around the handle, where the blade is inserted, I find it's helpful to do that, and then I just cut them with a handsaw in a vise, but preparing the handle like that allows for a clean kerf to help me keep the cut in the center. All of our mileage varies.

[Ray Gardiner]

Hi Alan,

I have plans to buy a small milling machine, seeing your grizzly at work has made me move it up to the top of the list. That Nichols horizontal mill looks pretty slick, the cutting speed is pretty impressive!.

Accuracy and rigidity is the problem with the drill press setup, (as you pointed out), but now I have an idea as to how it works, I will build a
better setup.

What TPI slitting blades are you using?

Regards
Ray

[Alan DuBoff]

Ray,

I personally am not too fond of the mini-mill, but it does work, and I give credit to folks who use them, I would have not thought you could use it for doing this, and several machinist friends of mine advised me against it, after all they do have plastic gears! They really need to be taken apart, have the cosmoline cleaned off of them, and oil/lubed properly. Then if you add the belt drive, they can be usable, but there is all types of limitations with them in doing a lot of machining...the low quality hand wheels and table screws, the speed to reposition the table, I always have to run the table from side to side to adjust my fixture, or have a difficult time getting the slotting saw in proper position...I guess it's a love/hate relationship with it for me. It is capable of doing some stuff, and it is capable to slot handsaw backs...I bought mine locally from a guy for $200 that used it to make prototypes out of plastic. He was milling small channels in plastic with 1/16", 3/64", 1/32" and similar sizes, so it didn't see a lot of use. They are what they are. A vertical mill is not the best for slotting, IMO, and the horizontal is much better for that purpose. The Nichols is a real mill, made for production work, and many of them were run 24x7, 7 days a week, for years on end...I'm not sure the mini-mill is even capable of running 24 hours.

They don't rate the saws by tpi actually, typically the amount of teeth for the circumference. The two pictured below are both .020".

Look at MSC, they have jewelers saws with high tpi, like this with 230 teeth on a 3" diameter:

(linky pic)


Opposed to this screw slotting saw that is 72 teeth for a 2 1/4" diameter:

(linky pic)


My Nichols has a 1" arbor, although arbors are pretty cheap on the used market, but a 3" blade will only provide 1" of cutting depth (less actually, because of the spacers), if you can get the arbor down to the workpiece. This is ok for saw backs, I will only go about 1/3 to 1/2 the width of the back, so 5/16" into a 3/4" width back, aprox. Again, all of our mileage varies. Maybe some of the professional saw makers can give you better data, I've only made a few saws.

Remember this is all relative also, you need to calculate the amount of teeth per the rpm of the blade in conjunction with the diameter of the blade to come up with the amount to cut, I don't have the formula off the top of my head. The mini-mill allows adjusting of 0-1700 rpm with factory plastic gears, but the belt conversion allows for 0-4300 rpm. If your patient the mini-mill is capable of a lot, but again, it is nothing like my Nichols.

HTH,

[Alan DuBoff]

Ray,

Here's the Nichols slotting a piece of aluminum for a slotting fixture, just playing around here before I do the real fixutre, I have a longer 2.5" thick, 4" wide, 20" long piece of aluminum I will make my master slotting fixture with. I will counter bore the t-nut bolt nuts into the top so the arbor can get down to the surface. I have a Bridgeport vise on my Nichols, that vise will hold this fixture level. That's how I slotted the bronze. I originally needed to stack 2 of these together to get the proper clearance on the mini-mill, the head doesn't go to the table...again, you can jury rig this stuff up and it will work, it's not rocket science, but I don't often like to jury rig it if I can help it. We all work differently...metal working is a whole different world in itself, just like forging is as well, as-is leather working...you have to calculate speed vs. cut vs. rake vs. material being used, etc...similar to using a high angle plane on difficult grain, you need to use different rake on the cutters for the type of metal being used.

I know about a thimble full of what amounts to a sea of information.

[Ray Gardiner]

Hi Alan,

The one I have been looking at has horizontal and vertical spindles, not as nice and heavy duty as the Nichols, price is pretty good, and I hope capability is adequate for the projects I have in mind. In a previous life I designed and built embedded control systems (including some xyz positioning systems), and have the half baked idea that I will add some NC capabilites at some time in the future.


This one comes with digital readout, not shown in picture above. You can just see the horizontal spindle behind the cutting fluid nozzle. Only power feed on the X axis.

Regards
Ray

[Alan DuBoff]

Ray,

That's quite a bit more machine than a mini-mill. That would work fine for this stuff, most certainly. The mini-mill will handle it if one can tolerate using it.

BTW, on the back you pictured above, you actually don't need to, and will run into some problems, if you slot that deep.

That looks pretty dangerous to me. Did you just run it through like a router table with your hands?

If you were to clamp the back down properly, on a table, you might find that the blade will bind as the back will be clamped where you've slotted.

Good use of available resources though! It got your back slotted! You still have all your fingers, right?

One of my friends has a Bridgeport clone (Kent, USA...pretty nice machine) with DRO. We sliced a piece of 1/4" thick bronze in a couple passes. I don't know that my mini-mill would handle bronze at all, let alone a couple passes...That mill you pictured certainly will handle harder metals than brass.

In America we're fortunate to have a surplus of vintage machines, and I love the ones from the 40s (WWII era). Many of my machines are from the 40s, woodworking machines as well.

[Michael Pilla]

I'm intrigued by all this slitting saw talk. I don't have a mill but would love to try an .020 saw for starting the slot in handles. Seems like a drill press can be made to work with some effort. How about a router table with an adjustable speed router set to it's slowest setting? (probably 5000 rpm).

Just curious.

Michael

[Ray Gardiner]

Hi Alan, Michael

It does look a bit scary, but it's running quite slow, around 60-80 rpm and I have backed off the belt tension, so in the event of a blade jam, it just spins. I push the brass through by hand until it gets too close to the blade and then use a push stick (actually another bit of brass that was just laying around)

I would say a table saw is several orders of magnitude more dangerous, that's not to say I am not careful and attentive.

The depth of the cut is way too deep on that first cut, I am thinking more of 3/8 or so would be sufficient. Although I am unclear as to what problems could be caused by cutting too deep.

Michael, I looked at the router table for a while before going with the drill press, the router table would work if you could slow it down sufficiently, and do it safely.

Here is the partially finished saw, I still have to polish the blade and cut the teeth.



I get better pictures with the scanner rather than the phone. Here is a scanned image of the handle



The wood is Australian Sheoak, finished with shellac and wax (about 5 minutes ago!) hard stuff to work but very stable.

Next job is pull it apart, polish the blade, and cut some teeth.

Regards
Ray

[Mike K Wenzloff]

...Seems like a drill press can be made to work with some effort. How about a router table with an adjustable speed router set to it's slowest setting? (probably 5000 rpm).

Just curious.

Michael,

A router is incredibly too fast. You'll have pieces of blade flinging everywhere you don't want it too.

Ray, if you have an X-Y table you can use that to secure the brass to and crank it through. You will have to reposition the brass unless you have one to clamp down to the drill press table that has enough X travel. Repositioning the brass is no big deal.

General discussion. A drill press can be utilized. I would heartily recommend anyone doing this that the drill press used have a check that can be secured in the column by a drawbar or such. DPs are not really made for side-load and one can with side pressure cause the chuck to come loose and or fall out. No real big deal as regards safety perhaps. And it doesn't hurt the chuck. The blade may/will snap but I think that's about it.

Take care, Mike

[Mike K Wenzloff]

Nice saw, Ray! I do like that Sheoak.

Take care, Mike

[Ray Gardiner]

Michael,

A router is incredibly too fast. You'll have pieces of blade flinging everywhere you don't want it too.

Ray, if you have an X-Y table you can use that to secure the brass to and crank it through. You will have to reposition the brass unless you have one to clamp down to the drill press table that has enough X travel. Repositioning the brass is no big deal.

General discussion. A drill press can be utilized. I would heartily recommend anyone doing this that the drill press used have a check that can be secured in the column by a drawbar or such. DPs are not really made for side-load and one can with side pressure cause the chuck to come loose and or fall out. No real big deal as regards safety perhaps. And it doesn't hurt the chuck. The blade may/will snap but I think that's about it.

Take care, Mike

Hi Mike,

Good points, I thought about the arbor dropping out of the morse taper, and the supporting block has a hole cut in it that the bottom of the arbor sits on, so that it can't drop down, also means that once set up I can't change the height easily. The main aim in mucking about with this was to see if it would work. I'm not sure I would be rushing to recommend it to someone as best practice!

That sheoak has a beautiful feel to it, once you pick it up you don't want to put it down.

Regards
Ray