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Chop saw cutting thick round stock.
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Previously:
https://www.homemadetools.net/forum/...372#post131334
https://www.homemadetools.net/forum/...485#post173761
https://www.homemadetools.net/forum/...314#post158015
https://www.homemadetools.net/forum/...030#post160598
https://www.homemadetools.net/forum/...807#post144124
I would lean towards calling it a cold saw. judging by the slow RPMs and the apparent signs there are teeth on the blade and not a consumable friction blade. But I have to wonder why there doesn't seem to be any coolant spray Cumming out of the nozzle positioned in front of the blade
Might be that it is just air to control the chips...Quote:
Originally Posted by Frank S
Yeah, from watching videos of various objects being fabricated from structural steel, I've often wondered why there is no coolant. It seems like the blade, though presumably designed to be used dry, would dull quickly. I usually use my portable bandsaw or my abrasive chop saw.
I have used abrasive cutoff saws for years, clearly this isn't one of those.
I bought one of the Evo cold cut saws, piece of junk, problem is with the clamp and the way the back of the vise is built. Made about a dozen cuts and the blade is worn out. I looked at the cuts and repeatability of cuts and using a setup where I had excellent coltrol of the process, the saw/clamp/vise/blade were the only variables. My abrasive cutoff saw did beter than the evo.
Bought a Makita - oh my - it is a pleasure to use. Clamp/vise are well designed, the blade is stiffer. I have made hundreds of cuts (probably over 700) on the same blade and it is just fantasic. I have cut many shapes - round/flat/plate/T-bar/bolts/rebar/etc. I even used it to cut a PTO drive shaft to length. The cuts are flat and straight. I have repeatability to less than 1/32" and I could probably make it more with a better stop for the material.
A cold saw is typically 150 rpm for aluminium and 75 for steel using coolant. I would think this is a carbide dry cut and the heat is carried away in the chips. I used to have a friction saw 22'' diameter at 3600 rpm, tungsten alloy blade.
Discounting the paint coating (yellow & blue?), maybe it's being reused. Anyway, the chips and cut face appear to be cast iron. Moderate speed, and dry, air is acceptable.
I have a 12" compound miter saw that I use to cut aluminum planking with. What was taking 3 minutes to cut with the band saw takes about 10 to 15 seconds with the miter saw. of course the carbide blade cost nearly 100 bucks but well worth it in time savings
Not to mention lifespan of circular re-sharpenable - repairable blade. For any adequate size band blade, they close in on $100 too. Proportionally speaking, an expense in heat-treating is tied to petroleum prices; tooling and gears for example, though it has a long service life.Quote:
Originally Posted by Frank S
I regard cutting in accord with goal of that particular item in process. ie, Cold sawing is clean, square, to length and sufficient finish to pass for done, but 100% hands on.
A well set bandsaw can tend it self, needing only to reposition material, narrow kerf, often better cutting nested or bundled material.
Chop saws beat all on moderate rod sizes and angle iron, low cost per cut of wheels, but calls for all-over deburring, a lot of sweeping afterward.
It's not far-fetched to combine two of these for certain advantages combined.