abrasive saws

[fiaroadster]

I need some schooling on how to properly use an abrasive chop saw. I have the HF 14" chop saw and am unable to make more than one cut (angle iron) without the blade glazing? over and not cutting any longer. Swapped blades for a HD replacement with the same results. Blade heats the **** out of the steel, puts a nice polish to the cut, but no cutting action. What am I doing wrong?

 

[Tripp2012]

That's a new one on me I use Dewalt blades for the most part and have never run into this. Not sure what you could be doing wrong just put a little presure on the handle and let the blade do the work.

 

[teamextreme]

Very strange. I've used various blades, cheapies, good ones, in a couple different saws for years and never had any issues. You can push hard or light, it just changes the speed it cuts through and the load on the motor. Never heard of a glazing problem. I've even used it to cut a hardened transmission output shaft that a bandsaw wouldn't even put a scratch in with no issues.

 

[Tucko]

I would double check to make sure you're using the right metal blade.

 

[HMCFab9]

I would double check to make sure you're using the right metal blade.

You're not using a masonry blade, are you? There are differences.

 

[Milton Shaw]

You are not using enough force down to keep the saw cutting. That heats the blade up and doesn't cut. Those need to be throwing a lot of sparks and pulling close to max amps on the saw to cut properly. If you have that plugged into a outlet strip with a breaker, the right pressure would blow the breaker. Those pull 11-13 amps at load and should be cutting.

 

[Cardboard Man]

All good advice above. I would also check to make sure the saw is not binding, as it sounds like you're not getting enough down force. When there is nothing in the saw, you should be able to push the blade all the way down through the slot with only a little tension from the spring. Sometimes the blade guard gets caught, or you have the stop set too high, or a piece of debris can make it bind. Make sure you have free movement through the entire cutting range.

 

[crewchief888]

You are not using enough force down to keep the saw cutting. That heats the blade up and doesn't cut. Those need to be throwing a lot of sparks

this sounds like the problem to me

 

[PugetDude]

I've noticed the same problem with my DeWalt Chopsaw, when cutting higher-quality steel, ie 4140. Normal A36 angle, bar and and A53 Pipe- it sails right thru. I deglazed the wheel by cutting a couple of pieces of A36 scrap, kept plenty of down pressure and kept the sparks flying...

 

[DIC]

Should go right thru angle iron.. How thick is it?

 

[Milton Shaw]

I forgot to add that how you position the metal in the vise also makes a difference. You don't want to cut with material flat in the vise on edge or if angle with the "V" up in the vise so that you are basically cutting through the edges.

 

[metalmagpie]

Those abrasive chop saws aren't meant for structural steel. They are intended for steel 2x4s i.e. sheet metal. They are very loud and very very messy, throwing grit and sparks all over the place. I suggest you get rid of yours and buy a 4x6" (or 4x7", or 5x7") import bandsaw. Those run quietly and cleanly and one blade lasts a very long time.

A real abrasive saw for steels has at least a 7-1/2 horsepower motor.

metalmagpie

 

[DanarchyCustoms]

If you're attempting to cut very thick steel then try this:
Every once in a while we would have to cut up some 2"x 2"x 1/4" square tube and that **** was nasty to cut with an abrasive saw. The trick I learned is (this is just my theory, but it always seemed to work) when the steel is very thick, you're creating tons of heat by just pulling straight down on the handle, almost hardening the steel (sorta like drilling metal). So what I would do is let the saw bounce a bit. Nothing too excessive, but just enough to prevent the steel around the cut from turning bright red. I would let it cut until the sparks slowed down and then let off for a second, and cut again for a few seconds and etc. Since then I never had problem with cutting anything. Hopefully it helps.

 

[crewchief888]

Those abrasive chop saws aren't meant for structural steel. They are intended for steel 2x4s i.e. sheet metal. They are very loud and very very messy, throwing grit and sparks all over the place. I suggest you get rid of yours and buy a 4x6" (or 4x7", or 5x7") import bandsaw. Those run quietly and cleanly and one blade lasts a very long time.

A real abrasive saw for steels has at least a 7-1/2 horsepower motor.

metalmagpie

so every abrasive saw with less than 7 1/2 HP isnt meant for anything except sheetmetal.

i must be doing something really really wrong...

cuz mine cuts fine

 

[fourjeepin]

I forgot to add that how you position the metal in the vise also makes a difference. You don't want to cut with material flat in the vise on edge or if angle with the "V" up in the vise so that you are basically cutting through the edges.

+1
I have found this makes a big difference

 

[alwaysFlOoReD]

I don't have a lot of experience but I found that lightly bouncing a piece of metal off the edge of the blade while running would clear the glaze off. Now don't go hammering the blade like you want it to disintegrate and you'll be fine.

Richard

 

[A_Pmech]

Those abrasive chop saws aren't meant for structural steel. They are intended for steel 2x4s i.e. sheet metal.

The better portables work fine on angle iron, tube, that kind of thing. The local steel supplier goes though one Bosch unit a year for cutting retail short orders. The limit seems to be about 3/8" to 1/2" in any thickness dimension. Then they just glaze over and it's done.

But yeah, 7.5 - 30HP does make the process more enjoyable if you can stay out of the spark stream.

Run a silicon carbide dressing stick over the wheel edge to de-glaze it if the inevitable happens.

 

[zkling]

Step 1, Get rid of current said chop saw
Step 2, Purchase a new or used off shore 4x6 horizontal bandsaw.
Step 3, Enjoy a quieter, cleaner work environment and a tool that is capable of cutting all metals.

 

[bop_pa]

I had the same problem with my hf chop saw. It takes forever to cut through square tube. I have been thinking about getting a cold saw or evolution saw.

 

[Sureshot]

It is steel you are cutting??????????

 

[taumac]

+1
I have found this makes a big difference

I forgot to add that how you position the metal in the vise also makes a difference. You don't want to cut with material flat in the vise on edge or if angle with the "V" up in the vise so that you are basically cutting through the edges.

I totally agree and also hard to cut on edge too, like taking sliver off edge. I use Norton or diabo wheels also. They last longer and cut better.

 

[clarkebd]

So some of you are saying something like this is better overall than a chop saw?
I don't have either yet, but have been trying to figure out what to buy. The biggest/thickest piece of metal I would be cutting is 2x2 1/4".

Do these band saws work better just because of the blade teeth vs 'grinding' action of the chop saw?

http://www.harborfreight.com/garage-shop/stationary-band-saw/horizontal-vertical-metal-cutting-bandsaw-93762.html

 

[terryo1965]

The wheels are glazing because the grain in the wheel is getting dull and when it gets dull they stop cutting and start loading. There must be a constant exposure of new grain to keep the wheel cutting. The dull grain falls out when the temperature in the grinding zone hits a level, then the bond that holds the grain melts and the grain is released which exposes new grain that can cut the metal. The key to a good cut is maintaining enough pressure on the wheel to have a nice shower of sparks coming off the part, too much pressure and you are going to create too much heat and have short wheel life and too little pressure and the wheel will load. I have seen many people "bumping" the wheel and it seems to work but probably isn't the safest practice. I think your best bet is to experiment and find the right steady pressure that is throwing a nice spark shower and let the wheel do the work.

 

[drmarkr]

So some of you are saying something like this is better overall than a chop saw?
I don't have either yet, but have been trying to figure out what to buy. The biggest/thickest piece of metal I would be cutting is 2x2 1/4".

Do these band saws work better just because of the blade teeth vs 'grinding' action of the chop saw?

http://www.harborfreight.com/garage-shop/stationary-band-saw/horizontal-vertical-metal-cutting-bandsaw-93762.html

Depends on how many cuts of that 1/4" 2x2 you'll be making. And how much space you have. And how much money you want to spend.

I cut quite a bit of structural (most less than 1/4" wall thickness) with my HF chop saw. Using all the good advice above, it's working just fine for my purposes....totally fine. The only time I've had glazing problems is if the piece required a "flat" positioning, but bouncing/intermittent tricks got the cut made. I'm sure I can find the right job that will *require* me to purchase a horizontal bandsaw though.....that's how lot's of my tool purchases are done.

"Why yes dear, I HAD to have this tool in order to get this project done correctly!!"

Oh....and one more thing. If a horizontal band saws are REQUIRED to cut structural steel, someone damn sure better notify all of the steel suppliers out here.....because all of the one's I frequent use abrasive saws to cut their structural steel...

 

[clarkebd]

Do the band saws makes less of a mess of material/sparks? I guess I'm still not understanding why by a chop saw if a 4x6 or 4x7, can better handle the material and not be as messy?

 

[metalmagpie]

Band saws make WAY less mess! Maybe a matchbox worth of metal shavings right at the saw. Also, they feed themselves, so you can put a piece in to be cut and go do something else while it cuts. You can stand the saw up and use it in vertical mode.

See http://tinyisland.com/Grant/4x6bsFAQ.html - oldie, but goodie.

 

[LX-Markham]

I would double check to make sure you're using the right metal blade.

You're not using a masonry blade, are you? There are differences.

It sounds like a masonry blade.

Abrasive saw is fine for most people. Would i trade it for a bandsaw? Absolutely! Much cleaner cut, quiet, and less messy. But until I have the money and space for one, my old Makita will have to suffice.

 

[donthelegend]

Horizontal bandsaws are the better tool, but they're more expensive and take up more space (by quite a large margin over abrasive saws).

Most people start with an abrasive saw simply because of the lower price.

 

[Guster]

Another trick an old timer taught me is to keep a piece of hard stone or ceramic(like a floor or roof tile) handy to de-glaze the edge of the wheel. I kept a strip of heavy floor tile from a flooring job that does the job every time. Just a light touch with the ceramic clamped in the vice.

I would also replace the cheap disk that came with the saw with a good quality one. They are not that expensive and it can make a world of difference. But I won't apply too much pressure as it can load up and destroy the disk.

Like others mentioned - whenever cutting any heavy profile it is best to align it so the blade contacts or cuts through the thinnest part of the profile rather than across the largest surface ie. if I was cutting channel I would cut through the webs with the channel on its back before turning it 90deg to cut through the back on edge. Otherwise trying to cut through the flat surface takes very long, uses up the blade a lot faster and possibly just end up glazing it. Just try it with some heavy flatbar and time the difference between cutting on edge and laying flat.

 

[Guster]

It sounds like a masonry blade.

Abrasive saw is fine for most people. Would i trade it for a bandsaw? Absolutely! Much cleaner cut, quiet, and less messy. But until I have the money and space for one, my old Makita will have to suffice.

I have both and I use both for very good reason. Hard materials and stainless don't cut very well on a bandsaw. It could be done but time and money spent it pays to keep the abrasive saw. I would absolutely love to have a nice large cold-cut saw however that is money better spent elsewhere. In the mean time I have great flexibility between the bandsaw and the chop saw.

 

[crewchief888]

i prefer a chop saw for it's portability, and the small amount of space it takes up.

i really have no floor space for a bandsaw.

probably the 2 biggest mistakes people make with abrasive saws are
1 improper down pressure (feed) on what you're cutting
2 orientation in the vice of what you're cutting

seen it many times with horizontal and vertical bandsaws as well.

i worked in a tool & die shop for 7 years, machining upset forging dies, and cut miles of T2 tool steel with a bandsaw.

 

[NUTTSGT]

It may not be how you you are cutting the steel or what blade you are using but it might be the HF saw may not have the balls to do the job.

Do you know anybody else that has a chop saw (not another HF unit) that you could try out ? Try cutting the same steel on theirs as compared to yours.

 

[sloppy]

It may not be how you you are cutting the steel or what blade you are using but it might be the HF saw may not have the balls to do the job.

Do you know anybody else that has a chop saw (not another HF unit) that you could try out ? Try cutting the same steel on theirs as compared to yours.

I have one of the HF saws and it cuts fine.. Its not a powerhouse by any means but its not glazing the blades..

Of course quality control is not their strong suit..

 

[NUTTSGT]

I have one of the HF saws and it cuts fine.. Its not a powerhouse by any means but its not glazing the blades..

Of course quality control is not their strong suit..

That's why I suggested comparing it to another saw with the same material.