Hello

I am finding it hard to cut thin metal sheets of stainless steel (aprox 0.6mm to 0.8mm) accurately, when cutting by hand.

I have tried using both a full-sized (30cm) and a junior sized (150mm) hacksaw with fine-toothed blades (32 TPI)

But I find it very easy for my cut to stray by 1+ mm.

I have had better luck using Super Pike Swiss Saw Blade

...which make a very fine cut (0.30-0.65mm) and have up to 30 to 16 teeth per cm [not inch!]. And with care good accuracy is possible, but there is very little 'depth' to the blade s(in the direction away from teeth) and this makes a cut difficult to keep straight, (even though it also makes it easy to correct!).

Any tips/suggestions?

- Do they make deeper blades for jewellers saws?

- Do they make hacksaws with a higher number of teeth than 32 TPI?

With thanks

J

Have a look at a fret saw or a deep throat jewellers saw. Cooksongold or others.

DescriptionEclipse Fret Saw 70-FS1R

Adjustable Saw Frame 6" Deep

Metal frame with wooden handle. Depth of frame = 6". Maximum cutting depth = 6"/150mm (due to depth of frame). Adjustable in the direction of the blade - loosen screw, slide arm along to required position, tighten screw. (Useful for re-using broken blades!) Holds saw blades up to 150mm in length. To fit blade: Loosen the screws, insert the blade ensuring the teeth are pointing towards the handle and facing away from the frame. Tighten one screw, then push the frame against the bench and tighten the other screw, keeping the frame under pressure. The blade will be held taut in the frame. Other adjustable models available: 999 735, 999 73B and 999 3059 (3" frame depth), 999 736 (4", 999 737 (5". For 3" Fixed Saw Frames see 999 73A & 734. For Piercing Blades see 972 010-110. Never use pliers to tighten the nuts on the frame as this will damage the screw thread.

Edited By David George 1 on 01/11/2021 13:57:08

Edited By David George 1 on 01/11/2021 13:58:00

The simple answer is you need more practice.

I’ve never seen deeper jewellers saw blades.

I have had better results on stainless with Platinum King blades than with Super Pike ones.

Dave

Sorry I think I wasn't clear enough... I think I need the blade itself to be deeper (in the direction away from the blades). I have a metal frame with a 5" clearance which is ample for me...

Meanwhile I think shall buy some more fine-toothed hacksaw blades from 'junior' sized (150mm) hacksaw. Maybe I need to find a higher quality make of blades... any specific recommendations?

With thanks

J

Possibly!

Where do you get yours - esp if you need them in a hurry?

J

When curtting a straight line with a piercing saw I find it easier to tilt the blade away from me rather than have it vertical. This puts more teeth in contact and makes it easier to sight along the line you are following.

If you do need more depth fretsaw frames will take piecing saw blades. A lubricant helps, jewellers use candle wax and I find trefolex good on steel.

Yes, good idea about cutting at an angle. That should help slightly at least.

...But what I fear what I really want is need is something fine-toothed that isn't a piercing saw! 

That's a good thought re lubricant. Trefolex looks slightly expensive but I have some Rocol RTD Compound, maybe that will work just as well... (??)



J

PS Meanwhile I have bought some new hacksaw blades ("Eclipse 71-132R Junior Hacksaw Blades 32tpi" ) to practise further with...  

Edited By John Smith 47 on 01/11/2021 14:53:14

Edited By John Smith 47 on 01/11/2021 14:53:57

Saw blades from Cookson Gold. Make sure you get the correct size - you want 3 teeth in the cut.

For lubricant plain old beeswax is as good as anything - although I tend not to use anything most of the time - the swarf is fine and tends to gum up the cut when a lube is used.

Dont saw fast, a gentle, slow stroke is best, with minial pressure - the saw should the 'thought' along for want of a better way of describing it - almost meditatively.

.

It may exist, but I’ve never seen it

Ignore the ‘razor saw’ ones that are only suitable for plastics and balsa

MichaelG.

.

Edit: __ just seen your mention of the Eclipse junior hacksaw blades

… do bear in mind that, because of the wavy edge, those produce a rather wide kerf.

Edited By Michael Gilligan on 01/11/2021 15:00:21

Try a size 2/0 piercing saw blade for .6-.8mm thick metal. The traditional blade lubricant is "nose grease"; just wipe the sides of your nose with your thumb and first finger, then slide them down the length of the blade. It works very well - I kid you not. That's what I do. When you feel that the blade isn't cutting like it did when you started, the chances are that you need to lubricate it.

As suggested already, tilt the blade slightly away from you to help keeping a straight cut. DON'T try pushing the blade in an effort to cut faster, it doesn't work and you're liable to break the blade. Let the blade cut at it's own speed.

It takes a bit of practise to use a piercing saw, but the effort is well worth it.

Yes, Platinum King blades sound like good advice as they are made from much harder metal than Super Pike, and I have bought some.

> tilt the blade slightly away from
To get clear, you mean that if the sheet of metal is held vertically in a vice, the tip of the blade is down, yes?

Oh, and teeth in any saw should always be pointing away from the handle, right?
(i.e. So that the cutting stroke is when you push the saw away from you.)

Wait, or is it like a "Coping Saw" where the cut is on the pull stroke?


> just seen your mention of the Eclipse junior hacksaw blades…
> do bear in mind that, because of the wavy edge, those produce a rather wide kerf.
Yes that's a good point. Do all 150mm hacksaw blades have that wavy edge?

Because I'm now wondering being a wavy edge plus a wider kerf will also stop it from cutting very straight. Presumably they make them like that to stop them from jamming, but I'm thinking that if I remember to lubricate (with nose grease or whatever) may I would be better off without the wavy edge...

J

Edited By John Smith 47 on 01/11/2021 22:25:50

Scribe a line on the material cramp between two pieces of angle then slide the saw along the edge of the angle for nice straight line.

What size pieces are you trying to cut?

David

I am using a small hobby table saw to cut 0.5 mm and 1.0 mm brass sheet. It should cut stainless steel with the correct cutting blade.

Mini Table Saw Woodwork Household Saw DIY Lathe Machine Cutting Tool Lifting 96W | eBay

Edited By Brian John on 02/11/2021 04:26:50

Well there is half your problem

Piercing saws are generally used vertically with the work laid flat and the saw handle at the bottom so you pull down to cut.

From that you should be able to deduce that piercing saw blades should be used with the cut on the pull stroke as you do with a coping and fret saw. Junior hacksaws direction depends on the type of frame, the bent metal ones are often better cutting on the pull but a frame with tension screw can cut on the push. Then we come to japanese saws which all tend to cut on the pull, hacksaws and western woodworking saws cut on the push.

The reason for using the piercing, fret and coping saw blades so they cut on the pull stroke is to keep the thin blades in tension, if you push them they tend to bow and that makes it harder to control the direction of cut.

The wider kerf left by a junior hacksaw can actually make it easier to cut straight as the saw is not being guided by the edge of the blade so you can steer it where you want rather than having to try and correct the path of a tight blade that has started to wander. They can also be used to cut shallow curves.

Edited By JasonB on 02/11/2021 07:14:48

How can I cut 0.8mm thick stainless steel sheet more accurately by hand?

More practice?

In general saws which just have a spring frame are better setup pull cut.

My junior hacksaws are set to pull cut.

A “full size” hacksaw has a rigid frame - so push cut is fine.

Jewellers saws are best used sitting down with a bench peg and the saw handle at the bottom, blade vertical.

As with all manual skills there is no escaping the need to practice. If you want to cut things straight and fast without putting in the hours at the bench you need a machine.

Dabe

Place your sheet of metal on top of a piece of 50mm thick insulation board. Put your goggles on and use a jig saw with a quality fine metal blade in it. I have cut out intricate weather vanes in stainless using this method.

For anyone [including you, John] with an interest in “piercing saws” … this is worth a look : **LINK**

http://www.antique-horology.org/_Editorial/SawPiercers/default.htm

MichaelG.

Another technique is to cut the piece oversized and then file or grind the excess off.

At first, due to lack of skill, it will be necessary to allow a wide error margin and spend lots of time filing! However, after plenty of practice, it might well be possible to saw accurately enough to get good enough results without tidying up. Much depends on the operator.

Although excellent results are obtained by hand methods, they take ages to do well. Partly eye-hand coordination, but also patience - hand-work can't be rushed. Some clumsy SODs lack basic coordination, but I think many get fed up half-way through and spoil the finish by rushing it.

Hand tools need practice and discipline of the sort needed to play a musical instrument well.

The advantage of filing is it removes metal slowly, making it less likely the tool will accidentally cut too far. But it still needs plenty of practice to do well. Machines are the best way of cutting fast and accurately.

Dave