HELP! Best way to cut ALUMINUM square tubing in thin slices w/o kickback?

[Geof]

Why not stick with your Miter saw and a triple chip blade running full speed using the suggestions rosko and I made for totally enclosing your material in a tube. We use fixtures like this for cutting various sizes of thin wall aluminum tube very successfully.

A band saw will be slow and it will be diffcult to get a nice square cut.

[martinw]

Dear toolmetal,

Just my two cents before you spend any money at the toolstore...if it is not too late.

I have cut loads of 1/8" wall Al. sections of similar sizes on my Dewalt compound mitre saw using a Dewalt non-ferrous blade, with usual success.

The rules I follow are to clamp the non-cut-off end firmly, and also the cut-off end if I can. The problem is that if you want a 1/2" slice, there is no way you can clamp it under the motor side of the saw. What happens is that the thin slice has no rididity during the cutting process, distorts and tips, from the top side into the rotating blade, and you get a classic kick-back. This tends not to happen with longer slices because they are more rigid. With thicker wall sections you will have better results for the same reason. One solution could be to enclose the tube externally in an external MDF sleeve similar to Geof's idea. You can do this fairly easily even with round tubing, but I have never tried it.

BTW, a possible reason for motor smoke is that the Al. chips end up inside the motor through the motor ventilation slots. The guy at Dewalt in the UK suggested finding a friendly lady who might donate a pair of stockings. You just put the stocking over the motor body to stop the chips getting in. Probably best to ask someone you know well or you might get a slap in the face...

Best wishes,

Martin

[toolmetal]

Hello Geof,

I already have the following Non-Ferrous blade ( "http://www.amazon.com/D1080N-Diablo-10-Inch-Non-Ferrous-PermaShield/dp/B00008WQ38/ref=sr_1_8?ie=UTF8&s=hi&qid=1233618875&sr=1-8"]Amazon.com: Freud D1080N Diablo 10-Inch 80 Tooth TCG Non-Ferrous Metal and Plastic Cutting Saw Blade with 5/8-Inch Arbor and PermaShield Coating: Home Improvement ). It really cuts the aluminum tubing (square and round) like butter!

I would absolutely love to continue to use what I have (my 10" Miter Saw and this Blade). However, I guess I am not quite understanding the setup, especially when cutting thin slices like 1/2" thin. How would I attach the "sleeve" to the opposite side where the 1/2" slice would end up? How would I safely clamp the sleeves to both ends fiven my miter saw's walls are so low? If possible, would you be able to insert photos of your setup?

Would your design be easier with a Metal Chop saw and the same type of saw blade as above? The chop saw does have a clamp on one end so perhaps you can comment on this.

Although I plan to try your idea as soon as I undertsand it better, but how about the following idea? Using my Table Saw with my Diablo blade to cut the square tube ... I can use the guide and slide and slice the square tubing like cutting ham on a ham slicer .... Of course, the table saw will be running at full speed so perhaps this would not be a good idea given the results on the miter. However, would the flat platform of the table saw give me the results I am looking for?

thank you

[toolmetal]

martin,

HAH ... Well, I can ask the old couple across the street ... But i think her husband is an ex WW2 war hero ... not worth the risk. I may have to go to Wal-mart and use the self-checkout lane :-).

Regarding the Miter saw (please read my previous post to geoff), I was wondering what type of clamps are you using? All the clamps i have seem to get in the way. Also, my miter saw is a basic one that i purchased JUST for this AL cutting purpose. the model is http://www.lowes.com/lowes/lkn?actio...-01&lpage=none

As you can see, the back walls (to clamp on) are not too high and clamping is tight. so, any advice or ideas on clamoing would be welcome.

I hust wish there was a cut-off saw with a full drop (no plate) on the other end ... So, when i cut the slices, they will simply fall to the floor. i am thinking this may solve the issues i am having.

i will look for your responses and Thanks again.

[Geof]

Our setup is not on the saw at the present time.

I will try making a sketch showing what I mean with my wooden (or mdf) tube but you will have to wait until tomorrow.

[martinw]

martin,

HAH ... Well, I can ask the old couple across the street ... But i think her husband is an ex WW2 war hero ... not worth the risk. I may have to go to Wal-mart and use the self-checkout lane :-).

.

Dear toolmetal,

Point taken...but if you get reckless and brave in your quest for motor protection, your social life could get very exciting.

Best wishes,
Martin

[mc-motorsports]

I hust wish there was a cut-off saw with a full drop (no plate) on the other end ... So, when i cut the slices, they will simply fall to the floor. i am thinking this may solve the issues i am having.

Whoops, I mis understood you. For that reason, a chop saw is a good thing, but I would definatly buy one with a cast aluminum base (I've owned both). Chop saws are more expensive, have 14" wheels and 1" arbors. Miter saws are cheaper, have 10" or 12" wheels, typically, and a 5/8" arbor. Miter saws are gererally much better quality for a cheaper price and miter saws are easier to find the blades you are using. Abrasive wheels don't cut aluminum for crap, they just load up. In the past, I've rubbed a piece of steel accross the cutting edge back and forth real quick to rough it up so that I could cut aluminum with an abrasive wheel, but it's still asking for trouble.

When your motor was smoking, would it start smoking under no load?

And did you end up buying the HF router control?

[toolmetal]

Hello MC-motorsports,

Thanks for your reply. let me know (or anyone else) about the following setup for my AL needs:

Chop saw: http://www.harborfreight.com/cpi/cta...emnumber=91938

Blade: http://www.harborfreight.com/cpi/cta...emnumber=91938 (Note, I have the 10" 5/8 arbor version of this and it cuts like butter ... other than the obvious issues with the miter saw that I have explained before)

As you know, the chop saw has a great built in clamp but still has a slight 3/4" to 1" base/edge on the right hand side (so the sliced pieces will truly not JUST drop to the floor). But, will this setup eliminate the safety issues I have experienced with the Miter Saw/Diablo Non Ferrous blade?

Thank you.

[ger21]

Anytime you try to cut small pieces on a wood chopsaw, there's the danger of parts flying. This can happen with both wood and metal. One thing that can help is to take 2 pieces of 3-4" MDF, and attach them together to form an "L" shape. Clamp this to the miter saw, and cut the aluminum on top of it. This gives you a zero clearance base and fence to cut on, which will make it harder for the parts to get caught by the blade. It's also a good idea to let the blade come to a stop before lifting it back up.


If you want precise cuts with much less chance of kickback, use a table saw with a sliding cutoff sled. With a good table saw (or at least one that's set up well), you can be much more accurate, faster, and safer. I've cut brass tubing on my table saw with no problem at all.

[martinw]

As you know, the chop saw has a great built in clamp but still has a slight 3/4" to 1" base/edge on the right hand side (so the sliced pieces will truly not JUST drop to the floor). But, will this setup eliminate the safety issues I have experienced with the Miter Saw/Diablo Non Ferrous blade?

Thank you.

Dear toolmetal,

1) If the saw can hold the stock and the cut-off rigidly on both sides of the cut, while cutting, it should work. Never mind the drop to the floor.

2) If you can replace that monster abrasive blade with something more like a proper saw blade designed for cutting aluminium sections, you are in with a chance.

3) If the clamp holds just the left side of the material, and not the right side as well, my VVHO is that you may as well stick with a 10" mitre saw . The reason being that the flat surface to the right of the blade on the saw you suggest will give exacly the same potential for kickback as a 10" mitre saw when cutting thin slices.

Sorry..

Best wishes,

Martin

[don2ddg]

We use Dewalt compound miter 10" saws in production cutting the same materials. Same type blade you are using. I would not recommend using a bandsaw if squareness or speed is critical. You will get kick back if you a not against the backstop on the cutoff piece. You can drill a hole through the table of the saw to put a clamp on the piece like on a mill.

[mc-motorsports]

Chop saw: http://www.harborfreight.com/cpi/cta...emnumber=91938

I hate HF, but I googled the other chop saws they are selling today and they are all sheetmetal bases?? 4 years ago you could get a decent chop saw with a cast aluminum base, Ryobi, Craftsman Professional or Millwaulkie... Today, it looks like they are all the same chineese crap.

Problem with the sheetmetal saws is they are rattle traps. They vibrate too much, slide around and make too much noise.

Where did the good tools go?

I currently have a Dewalt, and I hate it. Had a Ryobi and loved it, until I tried cutting 6" MS bar and burned up the motor. The Ryobi had a cast aluminum base, much quiter and smoother, heavier, didn't slide around.

If I ever get time, I'm going to remove the sheetmetal base and mount it to a 3/4" piece of steel. I have an obsolete fixture that is going to work perfect! Then weld on 1/8 X 2 X 2" MS tubing for the legs and make a fixturable chop saw for cutting parts in jigs, a little more precision and faster for production, hoping to get consistant joints for welding vs. mark a line and eyeball the cut.

[martinw]

Dear don2ddg,

Thanks for the advice, and welcome.

Best wishes,

Martin

[toolmetal]

Thank you for all your ideas and replies. For now, I will try the suggestions that will allow me to use the equipment I already have (10" Miter Saw with the Freud Diablo 10" Non-Ferrous Blade).

THE PLAN: One of my projects for today will be to make a Zero Clearance Insert and a Zero Clearance Fence for my Miter Saw. I will also find a better clamping system to hold the aluminum tubing on the RIGHT side of the Miter Saw. I will also hold and allow the blade to spin to a stop at the end of the cut before letting the blade back up. Because of the smoking issue with my test using the Router Speed Control, I will NOT use the speed control and allow the Miter Saw to run at full speed. I will mist the blade with WD-40 periodically throughout the many cuts.

I found a fantastic link on creating the Fence and Insert. http://www.woodnet.net/plansnow/mitersawtips.pdf

QUESTION: I know there is no FULL PROOF solution and I will always use obvious care and protection, but will having a Zero Clearance FENCE & INSERT virtually prevent any thin slices from getting caught and shot out as projectiles? Or the tube getting caught and bending/denting the material? Please comment on "THE PLAN" (above) and let me know your suggestions, additions or if you are in agreement.

Thanks

[Geof]

I promised a picture, here it is.

Your plan is good, just make your minimal clearance stock holder like my picture.

You do not need a fancy clamp, just insert the tube and the pull the left end toward you. This pushes the other end firmly against the side of the tunnel in the direction of the blade movement.

I have shown a hole for a stop pin. The cutting operation would be:

Insert stop pin.

Push tube up to stop pin and pull the left end toward you.

Remove stop pin remembering to keep pulling left end.

Perform cut, stop blade without retracting from cut. The cut-off piece on the right can not go anywhere except sideways away from the blade; it cannot tilt and get caught.

Retract stationary blade.

Push stock in to eject cut-off piece.

Retract stock, insert stop pin and go back to top.


When there is no longer enough stock protruding from the left end to hold it simply insert a piece of wood in the end to act as a leader. You should be able to cut down to with an inch or so of the end.

[toolmetal]

Hello Geof,

wow, what a great plan and thank you for the illustration -- very well done! I will try your design as well. I have the following questions:

(1) I imagine the stop pin hole is only as a stop marker for repetetive cuts ... Does it serve any other function while cutting?

(2) How snug/tight should the opening be to the AL stock? I imagine it would have to be a snug fit so that the stock does not have space to vibrate/shift around as the blade cuts into it. So, how snug should it be?

(3) I was thinking of making the tube of plexiglass (so i can see the material) and the base of 3/4" to 1" MDF for the base. The blade I own will make the inital cut through the plexi with no issues. But, regarding drilling holes into the miter saw, what type of screws would I use? The holes will not be threaded so would it require bolts with wing nuts at the top or bottom?

Thanks

[Geof]

Plexiglas is not suitable, it will crack and could break calamitously leading to fragments of everything everywhere.

The stop pin is purely a stop pin to set the length. If you left it in while cutting it would probably be okay...but if you daydream along like I do sometimes and retracted the blade while it was running the cut-off piece could jam between the blade and stop pin.

The fit does not need to be really snug, 1/32" clearance would be fine because you are pulling the stock to twist it in the tube and take up a small amount of clearance.

Just use 1/4" bolts for holding it down.

[martinw]

Dear toolmetal and Geof

That link to jigs for a mitre saw had me gasping in admiration..

http://www.woodnet.net/plansnow/mitersawtips.pdf

It all seems so obvious now. It didn't 24 hours ago.

Thank-you

Best wishes,

Martin

[BeginnerDIY]

toolmetal....I know it's been about 8.5 years from your original post, but I'm hoping that you have perfected this craft by now. Or at least remember the best way you ultimately ended up doing. I am trying to go even small and cut 1/4" square aluminum piping. This is the only good post I have been able to find on how to do this. Did the plans that Geoff gave you work well?

Thanks in advance!