Hacksaw blades

[Brasilikilt]

Hi everyone

I guess I have the curse of the dull hacksaw blades.
I've been cutting pieces for knife fittings out of copper, brass and sometimes mild steel, and prefer to use the hand saw and files for delicate work.
In the past I settled for the cheap Chinese blades, and they got dull pretty quick....No surprise there.

I go out and buy Norton blades, thinking that they'll be better, but even cutting through copper tubing and 1/8" and 1/4" brass plate, those blades become useless rather quickly. Perhaps there are finer aspects of hacksaw technique that somehow elude me.....
But still, would any of you point me toward a good brand of hacksaw blade that won't get dull after a few uses??

Thanks,
Iain

[monstermetal]

the ones that will last the longest are the ones that dont get used much

Ok sorry.... There are usually several diffrent types of steel and teeth configurations.. some are soft, some hard Id look into what the blades are you got. Someone with more experiance in the matter should chime in and tell you what to look for in a blade makeup ( I dont think its brand as long as your buying a good one like Starrett, Lenox, Norton or what ever)

[ianinsa]

There should be no surprise if cheap chinese blades don't last, however I have also had cheap made in USA blades not last! I think the problem is more in the cheap that the country of manufacture. That said, on the whole if it comes from Germany it's usually good and therefore expensive!

Copper and brass gutting heats up your blade and destroys the temper(of the blade)so it helps if you soap the blade, the easiest way to cut copper pipe is with one of those cheap & cheerfull pipecutters.

Sorry as I don't live on your side of the pond I can't advise you on specific local brands.

Regards Ian

[bigfootnampa]

Good blades are important and yes, the commonly available ones tend to be so poor as to be nearly useless! Lenox and Klein (plumbing and electrical toolmakers) tend to be much better blades and are pretty widely available. Good strong saw frames are also very important to the life of the blades (as well as their overall utility). As already mentioned saw wax can help a LOT (WD-40 works well if you have no saw wax handy... beeswax is decent too). A too weak frame lets the saw blade kink or twist as it heats up. Wax helps to keep the blades cleaner and cooler. NOTHING is of much help with junk blades! I have cut a LOT of metal with hacksaws over the years... years back it was not NEARLY so difficult to get a good blade.

[pkrankow]

A high tension saw frame doubles blade life alone in my experience. I have also found that appropriate tooth count for the work at hand helps. Softer and thicker metals (and plastic) like lower tooth count than thin and hard metals.

I tried bi-metal and high carbon blades without finding much difference in performance for my needs of a general purpose saw.

Phil

[MLMartin]

when cutting metal with a saw blade you really want to make sure there are at least 2 or more teeth in contact with the metal at all times. if not the teeth with strip off vary quickly. so for thin metals make sure to have a blade with many teeth, I use 32 tooth per inch for metal thats 1/8 or thinner, 24 tooth per inch for metal 3/16 to about 3/8 and 18 tooth per inch for about 1/2 and up. like said about keep the blade tight

[mcostello]

Lennox and Starrett are some of the best.

[Brasilikilt]

Wow....I apparently posted my question in the right place!

I had never thought of using any wax or lubricant on the blade as I thought this was mainly a thing for high-speed powered tools-such as a drill press or band saw.
There's a block of paraffin in the shop, so I'll have a go at using it...It's not bona-fide saw wax, but it's better than nothing, and should produce noticeable results I expect.

The Norton blade was just swapped from a cheapo frame into slightly newer, more robust hacksaw frame. It's a Stanley, so not the greatest, but definitely an improvement over the old one :-) I didn't suspect using a cheap frame had much to do with blade life, but in my own defense, I do tend to tighten up my blades like guitar strings. I discovered a long time ago that tight blade stays straighter and makes for a cleaner/truer cut.
Also I do tend to try to keep more teeth on the material rather than less in order to cut stuff...especially metal..I don't relish using hand saws, so the quicker I hack through my piece, the better :-)


When I go out on the hunt for new blades, I will definitely pay more attention to tooth count and type of metal.
It seems as though the collective opinion is that less teeth is better for softer metals, but I'll see what they have at the store and decide from there

Thanks so much for the feedback

Iain

[John B]

here is some advice on hacksawing that may be useful.

Hacksaw tips and techniques


Use a hacksaw blade with the correct pitch of teeth for the job in hand, fine pitch for hard materials and light wall tube, coarser pitch for softer materials.

Select the correct type of blade for you, All Hard or Bi metal

At least 3 teeth should be in contact with the metal at all times,

Teeth on the cutting stroke for large hacksaws face forward, and can be tensioned by various means, cam locks, wing nuts etc,

On the small frame hacksaws teeth face to the rear, and rely on spring tension of the frame to hold them in position

Correct tension on blade, (secure blade, remove all flex, then apply three full turns on the wingnut)

Secure the workpiece firmly and square to you when sawing, and at a comfortable height

Use the correct stance, feet apart and in line with the sawing line(s), and both hands holding the saw frame in line with the marked line. One hand at the front, and one on the handle.

Start the cut by lightly drawing back the saw until at least 5 teeth are cutting, then using the full length of the blade establish a steady rhythm (40 to 80 strokes per minute English or metric, keeping an eye on where the cut is going, this can be controlled by angling the vertical axis of the saw. You can use your thumb adjacent to the marked line to steady the blade until a starting groove is established

Use a relaxed grip on the saw, but enough to keep control of where the blade is going

Steady Pressure is applied on the cutting stroke (forward for the large hacksaws, backwards for the small frame only hacksaws) release the pressure on the return stroke to avoid excessive wear on the blade

In use All hard blades give a better straighter line than bimetal blades which have a tendency to flex and buckle as they loose tension as they get used
NOTE all 'all hard blades' are what they say, and if you are not experienced at sawing you may break them easily

Cheap blades should be avoided if you want decent results and prolonged saw blade life

Don't saw when you are fatigued, take a rest and then resume using the same set up.

NEVER start a new blade in an old saw cut

Ease off the pressure as you reach the end of the cutting to prevent damaging yourself.

It is not advisable to try and saw metal that is black to red hot, or metal that has been quenched after being forged, it will dull the teeth on the blade.

And like all hand crafts, you need to practice!

[Marksnagel]

Lennox is the brand that I'm most happy with. Ian is right, cheap is cheap no matter which country it comes from.

I'll not beat the poor dead horse yet again but watch for the name on the blade. Just because it has a trusted store name doesen't mean it is quality. ie ACE. They don't make the blades they just sell them with their name on the product.

Did I say Lennox?

Mark<><

[Bentiron1946]

NEVER start a new blade in an old saw cut......This one bit of advice that is generally ignored. My younger neighbor kept coming over once to see if I had one more saw blade, the problem, he was trying to use the old kerf and it just wasn't working for him. I took my last blade over and started a new cut a 1/4" away from his and finished the cut in just a few moments. The way he was sawing he also never eased the pressure on the blade on the back stroke, kept pushing down. He later bought me tow packages of cheap blades to replace all the ones he broke. I don't dis cheap blades, I bought two dozen blades for a dollar and they were great, made in India and dang near lasted for ever, I guess that old say that even a blind hog can find an acorn once in awhile applies here for sure. It'd be nice if they could produce that quality all the time, but there ain't no money in blades that last. :blink:

[Frosty]

Copper alloys can be a pain, they tend to load the teeth and gall so the blade over heats and loses it's temper.

#1 rule for metal cutting is the 3 tooth rule. 3 teeth on the metal at all times is optimum and nears critical cutting copper alloys. Having the proper TPI mens the cuttings have plenty of space between teeth to load without jamming so they're carried out of the cut and clear.

Lubricant is less important but using the wrong lube can be a deal killer. Oil is BAD it tends to make cuttings stick and you're back to galling and killing blades. I prefer parafin wax on the blade side above the teeth or dry graphite. Lubricant's primary function is making it easier on you and doesn't really make the saw cut better. Lubricant on a power saw, usually band saw is to clear cuttings in long cuts and help keep the blade cool. Properly adjusting the feed pressure/speed eliminates the need, I haven't turned the liquid pump on on my band saw in about 10 years to no ill effects.

Then comes the most important factor, technique. A steady moderate pressure released on the back stroke is what you're looking for. Pay attention to how it sounds and feels, like all tools a saw tells you what's happening, you have to listen and adjust.

Oh yeah, blades. I like Lennox and Sandvic blades bi-metals in my recipricating saws but single metals in my bandsaw. Proper TPI and technique makes more difference.

Frosty the Lucky.

[BIGGUNDOCTOR]

I have a wide mix of blades that have come from garage sales, fleamarkets, and auctions. I prefer bimetal just for the fact that they don't snap if I do something wrong, or something happens during a cut.

Wavy toothed blades will leave a wider kerf reducing drag, and clear chips better. Grip the blade between your fingers, and slide them down the blade. You should feel the teeth protruding sideways to form a kerf. If you don't feel the teeth that way the blade is toast (used), or won't last (new). Don't even bother using a dull blade, it will only cause you problems. Only use them for rough work that you don't want to ruin a new blade on.

When sawing thin stock angle the frame to the material to get more teeth contacting. Going at it perpendicularly will promote teeth stripping, and grabbing.

Copper, as soft as it is, is fairly abrasive to cutting tools. At work, the copper will wear the solid carbide cutting tools fairly rapidly, even while being flooded with oil.

On the return stroke let the blade drag slightly to help pull the chips out of the teeth. This is the same method used with files to help keep them clear them of debris.

Hacksaws take time, if you want to cut faster, get a power tool. Porta-Bands come in real handy.

I have a slick little tool that punches holes in band saw blade stock to make hacksaw blades. My Dad got it yearrrrrrrrrrrrrs ago.

[ianinsa]

I have a slick little tool that punches holes in band saw blade stock to make hacksaw blades. My Dad got it yearrrrrrrrrrrrrs ago.

You've got a whaaa............. Biggun you have GOT to post a pic.

Ian

[bigfootnampa]

It may depend somewhat on what you are cutting but I quite disagree with Frosty about the importance of lubricant on the saw blades. I used to use a portable circular saw with hollow ground plywood blades to cut stamped aluminum for mobile home skirting. I would cut about 4 sheets at a time and without the saw wax it was nearly impossible to get the days work done. I also cut lots of aluminum I beams that were about 1/4" thick metal and up to a foot deep... I was young then and FAST, you better believe that even WITH saw wax I overheated and kinked many a blade.

A word about waxes, "saw" wax is superior to anything else! WD-40 is quite good as it tends to keep the cutting teeth clean and does NOT collect dust as most lubricants will... I used to use WD-40 for lubricating the big panel saw guide beams in the mobile home factories because anything else would load up with dust and jam the saw glides (a big panel saw produces dumpster loads of sawdust daily). Bees wax and paraffin are okay but they are harder to coat the blades with and slow you down. Real saw wax is not very expensive and well worthwhile if you cut much... it loads on the blades easily, lasts well, lubricates better.

In addition to extending the life of blades, saw wax also helps to minimize tooth loading, galling (metal sticking to the blades sides), overheating and cuts the needed power to drive the saw... quite important if all that power comes from your arms! Just the quality of experience for the sawyer is SOOO much better when running a well lubed saw! Also cuts noise levels (which can be a very important advantage when cutting with power saws).

[macbruce]

I have observed that mixing different materials ie copper, brass, steel lessens the life of saw blades. I found if I cut say, steel and silicon bronze with the same blade in my bandsaw the blade crapped out quickly. The same could be true of hacksaw blades......... ..................If I took the time to change blades in the saw (pain In butt, but $40 per blade is a strong incentive) and use a blade designated for that material I got allot more hang time per blade..................it could help.......mb

[BIGGUNDOCTOR]

You've got a whaaa............. Biggun you have GOT to post a pic.

Ian

I will see if I can find it. Can't remember if I have hauled it out of the folks estate yet. Basically it is a y shape about 6" long with a die on one of the arms, and a threaded punch on the other. Think of a screw operated Whitney punch. You cut the blade stock to length, then screw the punch down till it punches a hole. Pretty simple really. Matter of fact any small sheetmetal punch should work. It is handy for things like making really coarse pitch blades for wood, plastic, meat. You can also make blades for some bow saws with it. Reminds me of a show covering the Indian shipbreakers. To cut the propeller blades off they had what looked like a 5'-6' hacksaw.

[ThomasPowers]

I too use bandsaw blade for hacksaw use, punch the holes with a whitney punch.

Now my oddity is that I use a bowsaw frame to get a large hacksaw, say 24-30" long, I use a good sandvik frame and punch the holes slightly closer than the wood blade to get more tension. I've sawn 2" round stock and trolley rail---in the field with this set up! Of course when the cops notice the hatchet, small shovel, leaf bags and hacksaw behind the seat of my truck.... (basic scrounging supplies!)

[arftist]

It may depend somewhat on what you are cutting but I quite disagree with Frosty about the importance of lubricant on the saw blades. I used to use a portable circular saw with hollow ground plywood blades to cut stamped aluminum for mobile home skirting. I would cut about 4 sheets at a time and without the saw wax it was nearly impossible to get the days work done. I also cut lots of aluminum I beams that were about 1/4" thick metal and up to a foot deep... I was young then and FAST, you better believe that even WITH saw wax I overheated and kinked many a blade.

A word about waxes, "saw" wax is superior to anything else! WD-40 is quite good as it tends to keep the cutting teeth clean and does NOT collect dust as most lubricants will... I used to use WD-40 for lubricating the big panel saw guide beams in the mobile home factories because anything else would load up with dust and jam the saw glides (a big panel saw produces dumpster loads of sawdust daily). Bees wax and paraffin are okay but they are harder to coat the blades with and slow you down. Real saw wax is not very expensive and well worthwhile if you cut much... it loads on the blades easily, lasts well, lubricates better.

In addition to extending the life of blades, saw wax also helps to minimize tooth loading, galling (metal sticking to the blades sides), overheating and cuts the needed power to drive the saw... quite important if all that power comes from your arms! Just the quality of experience for the sawyer is SOOO much better when running a well lubed saw! Also cuts noise levels (which can be a very important advantage when cutting with power saws).

Frosty wasn't talking about cutting aluminum with a skill saw.
A ggod lubricant for cutting aluminum with a skillsaw or tablesaw is kerosene or wd-40 spayed on the line of the cut before sawing. Wax works O.K. but not as good as light oil for this specific purpose. I have cut a great amount of alunimum without warping blades using this method.

[arftist]

Starret and Lenox both make very good hacksaw blades. A high tension frame is a great help, both to blade life and cutting speed.