JEWLERS SAW

[hortonstn]

i have a problem, every time i look at my jewlers saw i break the blade,
does anyone have a clue what i'm doing wrong
thanks
paul

[rich pierce]

If you change the angle the blade is in the work from the normal straight line, so the blade has to flex at the work, it will break.  I have to remind myself to hold the handle with little force and check that the blade is always 90 degrees to the work.  Also use a touch of lubricant and you'll be surprised how much this helps.

[heinz]

Are you mounting the blade so it cuts on the pull stroke as opposed to the push stroke used on hacksaws?

[alyce-james]

Paul; I pull the blade through a bees wax cake  (lubrication) before starting and make sure the tension is not to tight. Works for me. Jim.

[docone]

I am a jeweler. I can safely say, there is a reason they sell blades by the gross.
I rarely go finer than 2/0.
First of all, the teeth point to the person. Second, the beeswax goes on the backside of the blade. Tension does make a difference. A lot of jewelers have an hole in their bench to put the front side of the bow into so they can push the handle into the bow. When released, this puts solid tension on the blade.
The big thing with these saws is to go lightly. They are not Hack Saws, they are fine, high carbon steel, blades.
I have not found any secret to longevity with these blades. I go through a bunch every day. Some last longer than the others. Some last one pull, another might last several cut throughs.
Long light strokes work best for me. Also, keeping the material from moving helps. When I cut sheet stock, I have a pad that I use to pull down the blade into the work. Another trick I use is to use the non-toothed part of the blade to start the cut. I use .032, #67 drill bit to start on cut and pierce work. I still have room to turn the blade to start the cut.
I snap a bunch of blades each year. I get several grosses of them. I prefer the Rio Grande store brand. Cuts well, and lasts well. I also get blades run through my fingers. The blade snaps and I am still pulling. The other side goes right into my hand somewhere. Hurts, and bleeds well.
I do not know if this helps, but it is what I do.
Works for me.

[Meteorman]

thanks docone.
very instructive and helpful.

I suspect a lot of us cut sheet stock, however, and I'm having trouble visualizing what's happening here:

When I cut sheet stock, I have a pad that I use to pull down the blade into the work.

/mike

[kutter]

I use a piece of wood, about 2" wide, 3/4" thick that I clamp to the bench so it overhangs by about 5 or 6 inches. The end that overhangs has a V cut into it. That is where I do the saw work,,within that V. It keeps the sheet stock from flexing if you don't make it too shallow & wide. Just enough to work inside it and still maintain stability.

Maybe that's what 'docone' means by a pad,,I don't know..

If the sheet stock flexes even a tiny amount, it will pinch the blade on each down (cutting) stroke and the blade will break prematurely from the stress.

They're going to break anyway, that's a given!,,but keeping the cuts light, avoiding twists, keep the saw frame verticle (if sawing that way) and keeping the work steady and flex free will help alot.

Use a finer cut blade on the thin stock to avoid it grabbing,,just like a hacksaw on thin stock,,it doesn't cut so nicely when the blade is too coarse.

Protect your eyes,,those blades can really take a ride when they break. Sometimes they only break in two and both parts are still clamped in the frame, and you can shorten the frame up and use the longer of the two for a few more exasperating strokes if you really feel the need too.
But sometimes a section will break out and really take off. They can hurt.

[Acer Saccharum]

rule of thumb which I seldom(never) pay attention to: pick a blade that suitable for the metal thickness. There should be 3 teeth engaged in the metal to prevent grabbing. Teeth per inch (TPI) The thinner the metal, the finer the TPI.

Somebody here once posted a chart once of the tooth pitch as relates to the blade numbers. 3/0, 0, 0/3, 0/6, etc. Kind of too mysterious for me to understand, so I bought dozens of blades of different sizes. Also, I buy blades with ROUNDED BACKS, as they go 'round curves better.

The board with a vee in it is used to support the work while sawing. The main effect is that the blade is in the vertical position, so you are sawing in an up-and-down motion.

if you try to use the saw frame in the horizontal position, the weight of the frame usually tends to break the blade.

suggestion: search You Tube for 'jeweler's sawing.'

Tom

[Lucky R A]

    I tried the Vee mounting plate and the draw stroke type of cutting, but never liked it.  I just put my patchbox stock into my Parrot vice that is mounted chest high to a 6' guy.  I put my 2/0 blade into the frame with the teeth pointing to the front.  Before starting with the jewlers saw I make cuts from the outside into the sharp turns in the design.  I then make my cut using the jeweler saw as a normal saw.  Rarely will my cut be longer than an inch or so.  I rarely go through more than 2-3 blades doing a complete five piece box cut out.  You can tell when the set is gone from the tiny teeth and the saw binds even if lubed--it will soon break.  I keep repositioning the sheet metal so it is held motionless by the vice.  I find this method allows me a good view of what I am cutting and just seems more natural...

[Acer Saccharum]

Seems more natural......

Different strokes for different folks. 

I think the main thing is that the metal being cut need to be held without danger of twisting or bouncing, for that is death to a jeweler's saw blade. Any binding is a gone blade.

As you cut, run the saw at a slight angle so you are putting draft on your patchbox or inlay. You will probably file these lines clean, but the saw does a great job on the taper, esp where you can't get the files into.

[docone]

Basically, any bench pin will work. Without modifying, you have two sides to cut against.
I like wood to saw against. Again, you pull down against the metal with that small a blade. The 2/0 is a very agressive cut, and fine enough that it dresses up easily.
A bench pin is the basic standard, there are variants of these. I have several in metal that I use with my Benchmate.
It will take experimenting, but once you have it, the jewelers saw is very versatile.

[tuffy]

A little chart that may help you get started.

            Jeweler Saw Blade Specifications.docxJeweler Saw Blade Specifications

            Blade           Blade              Blade          Teeth           Recommended           Drill Size
            Size             Thickness        Depth          per inch       for B & S Gauge         for Piercing
   
             8/0               .0063”            .0126”        89.0             up to 26                        80

             7/0               .0067”            .0130”        84.0             24 – 26                         80

             6/0               .0070”            .0140”        76.0             24                                79

             5/0               .0080”            .0157”         71.0            22 – 24                        78

             4/0               .0086”            .0175”         66.0            22                                77

             3/0               .0095”            .0190”         61.0            22                                76

             2/0               .0103”            .0204”         56.0            20 – 22                         75

             1/0               .0110”            .0220”         53.5            18 – 22                         73

             1                  .0120”            .0240”         51.0            18 – 20                         71

             2                  .0134”            .0276”         43.0            16 – 18                         70

             3                  .0140              .0290”         40.5            16 – 18                        68

             4                  .0150”            .0307”         38.0             16 – 18                        67

             5                  .0158”            .0331”         35.5             16                                65

             6                  .0173”            .0370”         33.0             14                                58

             7                  .0189”            .0400”         30.5              12                               57

             8                  .0197”            .0440”         28.0              12                               55   


                      CW                 

[KNeilson]

I like sawing in a vertical direction as I was taught that way. I have several "pins" depending on what I am cutting. The smaller the item, the narrower the "V" in the pin. Acer makes a good point is to count the teeth Vs the material thickness, also hardness affects this a bit. I think trying to rush the cut is the biggest flaw you can do. I provide minimal force to cut, work more on defining the accuracy of the vertical movement than the line of cut and of course.... the 3 "P`s".... Kerry                   PS.... thx for the chart   PW

[Glenn]

Thank you CW for posting that chart.  It will be very useful.

[Thom]

docone: "Lubricate the back side of the blade." I have always lubricated the teeth. It appears that the beeswax builds up and clogges the teeth, however I never thought it was a problem.
Thom

[jrice]

John Bivins used a German made blade by Hercules. This blade, by this manufacturer, has a radius on the back of the blade that makes cutting a small radius possible without binding and ultimately breakage. A possible reason for beeswax on the back of the blade is those who are not using Hercules blades. I mount my blade with the cutting done on the down stroke. I do not use beeswax. Hope this brand tip helps. Regards, Jerry

[hortonstn]

thanks, for all of your in put it sounds like i'm not the only one with this problem,
i will try all your methods
thanks again
paul

[rick landes]

Two hints/things that work for me.

I use a modern stick lube that was designed for high speed metal cutting. I think it stays with the blade better than the beeswax. Most weld supply or machine shops have a stick available. A couple of bucks will give you a lifetime supply. It also works great to lube a drill bit or countersink.

Second, and I think this may be most important. Use a full length of blade cut if at all possible. I believe the kerf of the blade is lessened with each pass through the metal (or at least to a given point). If short strokes are used and then a longer stroke is used breaking will happen as the narrower short stroked width blade will end and the wider new blade will be pulled into the material. This is where IMHO many breaks are happening. The blade does not have the capacity to be pulled through the narrower groove and is pulled apart.

Just my two cents, but it does seem to bear out in my experience.

[okieboy]

 I don't use lube with my jeweler's saw, but on some other sheet sawing I put the lube on the part to be cut along the saw line. That way the blade is always getting freshly relubed as it goes.

[welafong1]

i wonder why you do not  here about Scroll Saw being used in gun building could you not cut out patch box's or small things to being to be inlaid in the stock ? there most be a reason
thank you
Richard Westerfield

[greybeard]

i wonder why you donot  here about Scroll Saw being used in gun building could you not cut out patch box's or small things to being to be inlaid in the stock ? there most be a reasonthank you
Richard Westerfield

Makes sense to me. If I had a scroll saw I would sure be givin it a shot.
Could be wrong I guess. with thin brass it would probably fave to be backed up with something??
     Bob

[bjmac]

i have a problem, every time i look at my jewlers saw i break the blade,
does anyone have a clue what i'm doing wrong
thanks
paul

"Don't look"! Seriously, the problem with jewelers saws is the torque that you place on the blade. If you control the side-to-side motion, you will minimize the breakage. Make a jewelers saw guide which in my case is a piece of 3/4" *11/2 maple. Drill a forstner bit 3/4 hole about 1/2' hole about 1/2' from the edge . Then cut a "V" into the hole. You will then have a place to put your rough and keep the saw blade at a 90* angle when cutting.

[James Wilson Everett]

Guys,

I know that this post is discussing the blades, but I thought that you may enjoy seeing an 18th c jewelers saw.  It works just the same as the modern ones do, but it is a much more attractive tool that those modrern "clunky" ones.  The first photo is of the jewelers saw I use and the second photo is from the mid 18th c John Wyke tool catalog.

Jim Everett

[P.W.Berkuta]

i wonder why you do not  here about Scroll Saw being used in gun building could you not cut out patch box's or small things to being to be inlaid in the stock ? there most be a reason
thank you
Richard Westerfield

I purchased a scroll saw just for this use and found that when you brake a blade it takes 3 times longer to change the blade than on a hand saw and I waste more time "fiddling" with the scroll saw - I gave up using it and went back to the hand saw.

[greybeard]

i wonder why you do not  here about Scroll Saw being used in gun building could you not cut out patch box's or small things to being to be inlaid in the stock ? there most be a reason
thank you
Richard Westerfield

I purchased a scroll saw just for this use and found that when you brake a blade it takes 3 times longer to change the blade than on a hand saw and I waste more time "fiddling" with the scroll saw - I gave up using it and went back to the hand saw.

Well that's it.   I guess I wont be rushing out and buying a scroll saw anytime soon. Thanks.
OH yea  Great thread too.    Bob