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Cold saw for thin aluminum extrusions

Fish On

Hot Rolled
Joined
Feb 23, 2014
Location
Foley, Alabama
We're regularly miter cutting these two proprietary extrusions, to make 4 sided frames. Extrusions are roughly 2 1/4" wide as, and 1.5 and 1.875" tall, with all .090" wall thickness. 6063 alloy.

IMG_20191031_124503170.jpg

Mitered in this configuration to make 4 side frames, with horizontal flange out. Pieces will vary from about 7" up to about 72".

IMG_20191031_124536123.jpg

Currently been using a cheap import 5x6" mitering bandsaw. It works, but it's slow and the saw is starting to frustrate me (it's getting tougher to align everything where it doesn't throw blades or break them - used to not be a problem).

I just went out and did a couple test cuts, and it seems it's taking 26 - 28 seconds to cut the simpler extrusion - that's from turn the saw on until the scrap drops - not counting clamping or anything. Not enough time to do something else, but enough that it seems like cutting these things takes forever. It will cut faster, but I've found that if we speed the feed up, the cut potentially starts to wander, and it messes me up during assembly.


I've always been somewhat afraid to cut these on anything other than a bandsaw, with the thin flanges. I cut plenty of aluminum on a generic woodworking miter saw, but stuff with thin flanges (especially miters), always goes to the bandsaw.

I've briefly thought about a non ferrous cold saw, but have been concerned that the high speed would still be a grabbing concern with the thin flanges. As such, I've been planning on just upgrading to a beefier bandsaw in the somewhat near future. Something that I can put a 3/4 or 1" blade on, and feed at a speed more appropriate to the material being cut, but that's a fair bit of cost and floor space for a tiny aluminum extrusion.

For the sake of being thorough, would a generic ferrous cutting cold saw (Scotchman Bewo or equivalent) be suitable, if set to the 88 or 90 rpm range? I've always heard that it will cut very slow, but we're coming from 28 seconds a cut here. Would the slow speed lessen the likelihood of the flanges catching? I ran across a couple videos this morning of aluminum solids being cut on a ferrous metal cold saw, and the cut speeds seemed remarkably promising.
 

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Go pick up a chop saw and a 10inch triple chip grind fine pitch blade, and see what you think

like this:
https://www.homedepot.com/p/Diablo-...us-Plastic-Cutting-Saw-Blade-D1080N/100043779

sorry about the despot link, I know they sell one

If it actually catches, build supports out of MDF or something. I did this on my big fully auto cold saw for some really tall extrusion years ago.

Idea is chip load stays low enough it won't damage part. So don't rush

Even going slow you should get to 10 seconds per cut.
 
Concur with gustafson. Fine pitch blade, and slow on the feed and this is an easy job. The issue is work holding and a different saw is unlikely to improve that, especially a slower one. Make up some supports for the different extrusions and orientations they should be used, and use a clamp if necessary (or if others are going to be doing this).

Also just last weekend I used a buddies sliding chop saw and it did something that I'd never experienced on a chop saw that I can remember. It actually wanted to lift the work if it was a narrower width and you "chopped" fully then slide into the work. Made perfect sense but I don't ever remember it being an issue with any saw I've used. So use a non-slider or limit the travel to make sure the blade is coming down on the extrusion and pushing it into the table/fence.
 
Also just last weekend I used a buddies sliding chop saw and it did something that I'd never experienced on a chop saw that I can remember. It actually wanted to lift the work if it was a narrower width and you "chopped" fully then slide into the work. Made perfect sense but I don't ever remember it being an issue with any saw I've used. So use a non-slider or limit the travel to make sure the blade is coming down on the extrusion and pushing it into the table/fence.

I think a not of newer non slider saws have this tendency as well. I have a 12" dewalt dual bevel miter saw, and it's geometry is different from the older dewalt 12" single bevel saw I used prior. They've pulled the pivot point/blade forward in relation to the fence, so it can cut a full 8" wide piece laid flat, or a 1x6" stood on edge, (board fits up behind saw arbor).

Great if you're a trim guy, cutting 1x6 and 1x8s, but not so great for us, as anything narrower than 1.5" wide is getting lifted up instead of pushed into the fence.
 
A straight chop saw

https://www.homedepot.com/p/RYOBI-10-in-Compound-Miter-Saw-with-LED-TS1346/306939211

again sorry for despot

and the blade linked you are 200 bucks into the experiment. IF it does not work, bring it home and re do the kitchen

if it does, consider a nice 3500 rpm cold saw

I've got all that. Set up right next to the import bandsaw.
IMG_20191031_154501504.jpg

I use the chop saw all the time for more rigid shapes (tube, etc). There's no way I'm comfortable cutting these shapes without some rigid workholding. I've had it violently snatch a piece away from me one too many times for that.

More importantly, though, the part time help that's usually sawing these frames for me isn't super comfortable sawing conventional shapes with it, much less these.

I'm wanting to go ahead and buy the 'nice' saw mentioned, and have it hopefully more or less replace both of the above saws - just want to get the right one.
 
I've got all that. Set up right next to the import bandsaw.
View attachment 268726

I use the chop saw all the time for more rigid shapes (tube, etc). There's no way I'm comfortable cutting these shapes without some rigid workholding. I've had it violently snatch a piece away from me one too many times for that.

More importantly, though, the part time help that's usually sawing these frames for me isn't super comfortable sawing conventional shapes with it, much less these.

I'm wanting to go ahead and buy the 'nice' saw mentioned, and have it hopefully more or less replace both of the above saws - just want to get the right one.

chop saws have clamps

what blade are you using

I have been cutting tons of finned extrusion a year for 25 years

it will work
 
Omga 350 mm chop saw with Tenryu brand blade. Tenryu makes blades for aluminum that are like magic. I cut .75 x 3 dry like it is butter. Not sure but think their blades are hand tensioned. Made in Japan and a local sawsmith actually was called by them to go to Japan and train them how to do it. Cold saw on thin stuff would be my last option.
 
I'd be turning that extrusion around and cutting with the tall side clamped against the fence, build out the fence so it supports the return as well. That is for cutting with a high speed chop saw. Get a really good blade and stop fussing with that POS bandsaw. Do not cut that shape or most any shape of aluminum on a chop was without clamping, sooner or later it will get you and it sounds like you already know what that is like.
The pieces are small enough that you could build the fence as a complete assembly and just screw or bolt it to the chop saw as needed and get the job done. Clamps included all set up ready to go.

Good luck.
 
I run our cold saw somewhere between hot and 11 speed for cutting steel, so not sure how much it would tear out those sections. When I doubt use bandsaw, well because, bandsaws are almost always better and faster (cost more per cut tho). A good bandsaw should be able to slice that in the 3 -5 second range, vices should be air over hydraulic or hydraulic. The saw swing from side to side will eat your time way more than cut/clamp time.

Even a saw shaped saw blade holder shouldn't wonder to much over that section. Set your blade tracking on both wheels, then set guide arms to neutral axis, then set guide angles, then pressure. Your little scissor saw should be able to run thru those with all she's got without blinking. Make a set of "soft jaw" toggle clamps on the operator side to expediate sawing.
 
I think you need a Pistorius. They are out of business now, I think, but there are hundreds of their saws out there- they are miter saws meant to cut aluminum extrusions.
YouTube shown cutting wood, who knows why.

Pistorius Equipment

theres a bunch of Pistorious' on ebay right now for between just under a grand, and mebbe 3 grand. Well worth it. They were the standard of the industry for decades.
 
Omga 350 mm chop saw with Tenryu brand blade. Tenryu makes blades for aluminum that are like magic. I cut .75 x 3 dry like it is butter. Not sure but think their blades are hand tensioned. Made in Japan and a local sawsmith actually was called by them to go to Japan and train them how to do it. Cold saw on thin stuff would be my last option.

Tenryu America, Inc. - Tenryu Website Products page

Single mitre saws - OMGA Industries, Inc.

"Something like this" - dry, not wet - can be found at the strushion distributors in Hong Kong that cut loominum door and window and shower-door and architectural trim and framing all day, every day for a steady stream of contractors.

Whatever they use, it is seldom idle, and surely earns its rations.

The way it is done in Asia is take dimensions, go away, come back and drop the precuts into place slicker'n Owl snot, even for sidegodlin openings. Read "nearly ALL of them". I did say Hong Kong?

No need for the contractor to even OWN a saw, carry it onto the jobsite and back, nor even make a mess.

Cuts are very nearly perfectly burr-free as well.

Got to keep in mind that metal is used more extensively out in the tropics. Wood and moisture => food for far too many things.
 
I have 2 of the T50 350 saws, complete with the Omga cabinet stand with dust collector. It takes 2 very strong men or a hoist to lift the saw from a pallet onto the cabinet. 480 volt chop saws.
 
I have 2 of the T50 350 saws, complete with the Omga cabinet stand with dust collector. It takes 2 very strong men or a hoist to lift the saw from a pallet onto the cabinet. 480 volt chop saws.

I noticed a price that was a LTTTLE bit higher than what Horror-Fright gets, too. Or maybe the decimal point got cornfused and slipped a few positions?

Go figure "the good stuff" commands prices according!

:D
 








 
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