jack620 30th August 2022, 05:49 PM I've always installed my coping saw blades to cut on the push stroke. The coping saws at the school where I work usually have the blades installed to cut on the pull stroke. I assumed someone was installing them wrong, but thought I'd better consult Google before saying something. Looks like I've been doing it wrong all these years. Most websites are saying they should cut on the pull stroke. One said it is a matter of preference which way they should be installed. I'm curious to know which way people on the forum install their coping saw blades?
derekcohen 30th August 2022, 06:16 PM I saw on the pull - the blade is in tension, not compression, and is effectively stiffer.
Regards from Perth
Derek
Greg Q 30th August 2022, 07:02 PM Mine is installed on the pull, a skilled carpenter friend had his on the push. I converted him to after getting his help for a day and trading saws.
But the real answer is a Collins coping foot on a jigsaw.
Chief Tiff 30th August 2022, 07:36 PM Same here; I cut on the pull stroke.
If you’re used to pushing and it works for you then I wouldn’t fret about it.
Colin62 30th August 2022, 07:56 PM I wouldn’t fret about it.
I see what you did there…
Chesand 30th August 2022, 08:38 PM Same here; I cut on the pull stroke.
+ one.
D.W. 31st August 2022, 06:34 AM do whatever you like at the bench. If you build a coping jack and use it to cut something, then suddenly the idea that coping is usually done on the pull stroke will make sense.
OK...so I can't find a picture of what I'm talking about and don't want to dig mine out. Figure something similar to the mouth on a sawbench hooked to the bench.
The same jack is used with a fretsaw. Maybe I've got the wrong word for it.
Harpsichord and Violin Building in the 18th Century (3 of 4) - YouTube (https://youtu.be/zdmegtODOhM?t=405)
Like this, a little circular hole in the middle and you can support cutting thin items on the pull where they'd be difficult to cut otherwise.
jack620 31st August 2022, 09:03 AM OK...so I can't find a picture of what I'm talking about and don't want to dig mine out.
Like a jewellers bench pin?
D.W. 31st August 2022, 09:59 AM Like a jewellers bench pin?
Yes!! like a bigger version of that sized for stock thick enough to use a coping saw.
IanW 31st August 2022, 06:54 PM ..... the blade is in tension, not compression, and is effectively stiffer....
Derek, the blade is held in tension by the frame & the cutting forces are transmitted to the frame exactly the same way whether the teeth are cutting on the push stroke or the pull stroke.
Would you put the blade in to cut on the pull stroke with this (a bowsaw built to take coping saw blades)? 516392
Occasionally I do, when I want the cut stroke to pull the work against a stop or a "birds-mouth" support though I very rarely use it that way, 99% of the time it's set to cut on the push stroke. And the reason I prefer to use it cutting on the push stroke is because it doesn't feather the line I'm working to.
There are no mechanical reasons for mounting the blade either way, it's a matter of personal preference & how the work is being supported. The blade will cut the same whichever way the teeth point but you, the operator, may find it easier or more comfortable to use one way or the other, & that's the "correct" way to have it..
:)
My 2c
Cheers,
Oldmeadow 31st August 2022, 08:41 PM I like your thinking IanW and think that this is dependent upon the stiffness of the saw frame. If you're using a rock solid one like your timber one, I think the forces would be relatively even. If a cheap/crap saw that flexes significantly is used, I think that a pulling stroke would be more effective.
ie. When pushed, a flimsy saw frame may bend slightly when pushed. This could lead to a loss of applied tension onto the blade. Conversely, when pulled the tension is more stable as less force needs to be transmitted through the saw frame.
The conclusion I'd take from it is... use a good saw.
taz01 31st August 2022, 08:46 PM I would have thought Derek is right. The frame would compress slightly on the push stroke, expanding on the pull
The force isn't not exactly the same throughout the frame due to the handle not being in line with the cross beam. There would be some rotational force on the arm with the handle causing the effect.
The tension applied to the frame would make this small but is think it could be noticeable.
Regards
Adam
Sent from my SM-S901E using Tapatalk
derekcohen 31st August 2022, 08:56 PM Derek, the blade is held in tension by the frame & the cutting forces are transmitted to the frame exactly the same way whether the teeth are cutting on the push stroke or the pull stroke.
Ian, imagine the coping saw blade is a Japanese pull saw. The pull saw does not even have a frame. It may have a back, but it is easy to kink/concertina a thin Japanese blade if you push it. That is compression. When the saw is pulled back, the blade goes into tension. This adds stiffness.
Regards from Perth
Derek
jack620 31st August 2022, 09:47 PM No doubt there is a small amount of flexing of the frame on the push stroke, which would slightly reduce the tension on the blade. However, in roughly 45 years of doing it the “wrong” way I’ve never had a blade fall out. In fact, the setup is so rigid, it has never occurred to me to set the blade to cut on the pull stroke.
derekcohen 31st August 2022, 09:48 PM Jack, try it the "other way", and let us know what you find.
Regards from Perth
Derek
jack620 31st August 2022, 10:02 PM I certainly will. I have two of the bog-standard Eclipse metal frame coping saws that have been around forever. I’ll set one up each way.
Chief Tiff 31st August 2022, 10:15 PM I’ve found that with the traditional steel framed saw (I have an Eclipse and a Bahco) using it to cut on the push stroke does significantly reduce the tension on the blade leading into the cut due to the frame flexing. In tough hardwoods or thick softwoods I can see the blade bow so much that the cut isn’t flat bottomed but curved. The newer generation of saws like the Knew Concept are much more rigid but their photo gallery still shows it used on the pull.
However; 45 years of doing it one way would be rather tricky to change at the drop of a hat without an immediate and significantly observable improvement. Sure; give pulling a go just to see what all the fuss is about but to paraphrase Ian the best method is whatever works for you personally.
D.W. 31st August 2022, 10:54 PM a great deal of pulling being easier isn't just tension. It seems intuitively like the tension should be the same either way, but it depends on whether a stiffer part of the saw is on the side of the blade that's in tension.
But the other factor that's significant is that we naturally push with downforce and we don't pull with as much of the same.
The Spin Doctor 31st August 2022, 11:19 PM I saw on the pull - the blade is in tension, not compression, and is effectively stiffer.
Regards from Perth
Derek
Yup. If it's a regular coping saw pull is your only option. Though Derek, I hear you got one of those fancy ones that are real rigid so pull push is probably at the users discretion.
Some like push but if you look at the set up as a whole, often you'll be cutting on a bench or support of sorts, and the biomechanics, pull is the better option regardless of the blade tension. They're for really fine cutting and pulling gives the user better control, direction and pressure over the blade...
The Spin Doctor 31st August 2022, 11:28 PM However; 45 years of doing it one way would be rather tricky to change at the drop of a hat without an immediate and significantly observable improvement. Sure; give pulling a go just to see what all the fuss is about but to paraphrase Ian the best method is whatever works for you personally.
Prime the brain with a few cold ones first...
IanW 1st September 2022, 09:05 AM OK, OK, I should have said "provided the frame is adequately stiff", the tension remains the same. Oldmeadow & taz, you are quite right to point that out, thankyou
If the frame can flex under sawing forces, then yes, there is going to be some loss of tension on the blade. If the frame is symmetrical, the loss of tension should be equal in either direction but by cutting on the pull stroke, the tension is absorbed through the handle & does not need to be transmitted by the frame, so in that respect, you can make comparisons with a Japanese "pull" saw, but it indicates uyou are not getting the full benefit of the frame.
But struth, some of you blokes must be heavy on your saws! Even the cheap metal-framed coping saws I used before I got sick & tired of the blade-holders pulling out of the wooden handles were quite stiff enough to use with the blade either way.
Like I said, there are valid reasons for using the blade either way. I first used a coping saw for coping (funny that), and it makes sense to put the blade in to cut on the push stroke so you can cut from the "show" side by placing the skirting or whatever against a firm support & off you go - it's kinda tricky to hold a 12 foot length of skirting on a bird-mouth & cut on the pull stroke..
So I stick to my guns that there's no right or wrong way when it comes to blade orientation other than what suits the particular application. If your coping saw won't cut as well when pushed, then either your frame really is cheap & nasty or your technique requires a little revision, imo.
BTW - we are talking about coping saws & not fretsaws? The long, flexible frame of a fretsaw makes it a whole 'nother animal.....
:)
Cheers,
GraemeCook 1st September 2022, 01:12 PM Maybe I am clumsy?
I either cut on the pull stroke, or break the blade on the push stroke.
IanW 1st September 2022, 01:33 PM Maybe I am clumsy?
I either cut on the pull stroke, or break the blade on the push stroke.
Graeme, It's quite possible your blade isn't adequately tensioned, but you could be heavy-handed as well.... :U
I've broken plenty of fretsaw blades & dozens of jewellers saw blades, but can't recall ever breaking a CS blade. Mine are just Eclipse brand, bought from the big green shed - they are pretty robust things, but not very good blades. I always give them a quick touch-up with a needle file before I put them in the saw - they cut infinitely better after a light sharpen. They are soft & file like butter so soon dull. I can usually manage one more sharpen, but by then the set is coming off too much, so it's time for a new blade.
I don't use my little bowsaw/coping saw all that much, I prefer my 10" bowsaw with its longer stroke. My home-made blade is far better quality material (1095 shim stock) and stays keen much longer, but it is about 4mm wide (that's as fine as I've manged to make them) & can't cut as tight a circle as a CS blade, so the coping saw has to come out for the tight bends....
Cheers,
Ian
GraemeCook 1st September 2022, 03:18 PM Graeme, It's quite possible your blade isn't adequately tensioned, but you could be heavy-handed as well.... :U
Probably right on both counts.
I rarely use a fret saw or coping saw so my technique is probably a bit rusty.
Also my saws are rather historic with flexible frames - el cheapos bought from BBC Hardware many mooons ago - remember them, a precurser of Bunnings? Will upgrade when I have the need to.
paul.cleary 7th September 2022, 07:09 PM Back when schools had woodwork classes the coping saw blades were always installed to cut on the pull stroke because of economics. The students broke lots fewer blades on pull strokes than when the blades were installed to cut on push strokes.
Mobyturns 7th September 2022, 08:09 PM I was taught to use the pull cut and have always used a pull cut, 'cept when I don't. :D
I believe that the pull cut gives you more control / dexterity and a cleaner cut with light framed coping saws. We used them a lot to scribe mouldings prior to the ready availability of RADS and compound miter saws.
Alkahestic 7th September 2022, 09:48 PM I broke so many blades when starting out with a coping saw, it was embarrassing. It was the turns that always got me. It seems contrary to the popular method, I have it cutting on the push stroke in a Groz branded frame, so nothing special. I find I'm a bit more gentle with push strokes and turns and I don't break blades anymore. Side effect of using push saws for joinery maybe?
A Duke 7th September 2022, 10:26 PM Hi,
I use it either way, depending on the job, I decide at the time depending on what I am trying to do.
Regards
D.W. 8th September 2022, 01:13 AM I broke so many blades when starting out with a coping saw, it was embarrassing. It was the turns that always got me. It seems contrary to the popular method, I have it cutting on the push stroke in a Groz branded frame, so nothing special. I find I'm a bit more gentle with push strokes and turns and I don't break blades anymore. Side effect of using push saws for joinery maybe?
I haven't broken a lot, but I use a coping saw a good bit. I've noticed that when the cut gets forceful enough to feel it and heat becomes an issue, a break is not far behind. Not due to a catch or a big tug, just - ping.
outside of site trim work, I've learned to "go to a different place" when coping and fretsawing, and concentrate more on keeping the cut moving at a steady rate and following the line- as if you're a human sewing machine. Not a suggestion for anyone, just what I do as I'm often doing work someone would do on a machine, and focusing rough handwork to be accurate usually ends up saving time down the road vs. bulling through a cut.
Bulling through a cut feels good, though.
IanW 8th September 2022, 09:13 AM .... It was the turns that always got me.....
I've been using fret & coping saws since I was 11 or 12 & learnt intuitively (but painfully slowly!) rather than any formal instruction or analysis of the process & it's probably only in the last 20 years or so that I put much thought into saws & sawing. So it wasn't that long ago that I became consciously aware that when making tight turns I automatically rolled the saw left & right a bit on alternate strokes to increase the width of the kerf & allow the blade room to turn & follow the line. The rather coarse set on most coping saw blades is intended to help with curves by leaving a wide kerf - a pity they don't sharpen the darn things properly as well!
What has clued me in on the turning business is using jewellers saws & trying to make right-angle turns in brass or steel. The set on JS blades wears down relatively quickly in harder metals, which narrows the kerf to the point they start binding after a while even on straight cuts, no matter how gently you saw. So you need to do the left/right shuffle quite consciously when making tight turns or the blade jams & breaks very smartly. I destroyed a few dozen blades learning to use my JS effectively - good thing they are relatively cheap!
.... . It seems contrary to the popular method, I have it cutting on the push stroke....
I haven't done a careful count, but I got the impression from the responses so far that the push or pull camps are pretty even, with a couple like myself who use them either way depending on the circumstances... :;
....I find I'm a bit more gentle with push strokes and turns and I don't break blades anymore. Side effect of using push saws for joinery maybe?...
Maybe, but I suspect it's just using saws in general & developing your "touch". It seems to me that if you use any tool enough the hands & cerebellum eventually figure things out together without a lot of conscious input from the "thinking" part of the noggin, but most of us just don't use fret & coping saws enough to pick up those little knacks that get them working to full capacity.
:)
Cheers,
rustynail 8th September 2022, 02:02 PM I think you will find the pullers are trade taught and the pushers are self refined.
markharrison 8th September 2022, 09:27 PM I've always installed my coping saw blades to cut on the push stroke. The coping saws at the school where I work usually have the blades installed to cut on the pull stroke. I assumed someone was installing them wrong, but thought I'd better consult Google before saying something. Looks like I've been doing it wrong all these years. Most websites are saying they should cut on the pull stroke. One said it is a matter of preference which way they should be installed. I'm curious to know which way people on the forum install their coping saw blades?
I've tried both ways and -- before I bought a coping saw that could actually tension the blade properly -- I preferred to use it on the pull stroke.
I bought the Knew Concepts coping saw a few months back and I now prefer to cut on the push stroke.
GraemeCook 9th September 2022, 03:08 PM ... I think you will find the pullers are trade taught and the pushers are self refined. ...
I've tried both ways and -- before I bought a coping saw that could actually tension the blade properly -- I preferred to use it on the pull stroke.
I bought the Knew Concepts coping saw a few months back and I now prefer to cut on the push stroke.
I bought a couple of el cheapo frames and they were so flexible that they kept breaking blades on the push stroke, so I tried pull strokes - it works for me.
If I ever get a New Concepts or similar, then I might review that opinion.
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