Bi-metal hole saws

[shortfuse]

There was recently a thread about drilling in sheet or plate steel, but I don't want to hijack that thread, so starting a different one here.

I need to drill a few 1 inch diameter holes in 1/8" and 3/16" steel plate. Right now my only choices on brand and type are limited since we live in a rural area. I was wondering what you guys have used that cut best and have durability for BI-METAL 1" hole saws. I'll be using them on my drill press with the lowest speed and lube. I don't have access to plasma, CNC, O/A, etc.

My local brand choices are limited to:
Milwaukee
Bosch
Klein
Ridgid

If I want to go with carbide hole saws and maybe include Lenox bi-metal, I have to drive 90 miles round trip (add $20 for gas). If I gotta do that, then I'll order online.

[jordan_5600]

i have Milwaukee...they work good. Just take it slow and easy as you said and lots of oil.
Homedepot has them for $79 i think too.

[norite]

I have used Milwaukee, Greenlee, Lennox, Starrett and Klein. All are good AFAIAK. I haven't used the Bosch but going by their bi-metal jig saw blades I think they would be good also. No experience with the Ridgid but they make great pipe cutting and threading tools.

I'd go with whatever you can buy cheapest, or your personal preference, they should all be fine. Biggest factor for me is the mandrel and pilot bit assembly. They all work but some have or don't have hex shanks on the mandrels and some have better or worse pilot bits and means of securing them. Some will rattle themselves apart from vibration. Again it's your preference.

[74fencer]

I'll second Jordan, that is the kit I have and it is pretty decent for price.

[tnmgcarbide]

m-42 cobalt takes the heat of a too-fast-drillpress better than plain m-2 hss . i like morse cobalt , but
that's what i can buy locally . unless you've a macho drillpress , i wouldn't go the extra expense of carbide-
most major mfgs have a premium cobalt line , but if you have the right rpm for the tool - regular bimetal
should be just fine in mild steel.

anyway , whatever you choose.. hss cs= 80sfm x 4 / 1" . so 320 rpm for a 1" m-2 saw . cobalt can
take more heat , so 400-450 rpm for m-42 . use lots of oil, and use a chip brush to clear the teeth often .

unless you need the whole kit , a holesaw and arbor / pilot drill is inexpensive enough .

[REDONE]

I understand your predicament, but I honestly think that if you're going to drill more than 5 or 6 holes in sheet, or intend to complete 1 hole in anything thicker than 1/4" (or in stainless) you're gonna want carbide. Even if it means ordering off the internet. I buy my carbide hole saws from a local industrial tool supplier "Greenshields", and they're Milwaukee brand.

If there's ANY kind of industry near you regardless of how rural (you don't show your location) any kind of small manufacturer or automotive/agricultural machine shop has a supplier (like Fastenal) that probably delivers to your area, keeping your business quasi-local. I know that the carbide ones cost $40-$80 for regular sizes, but you'll burn ten bi-metals before you dull a carbide that can be resharpened. I generally keep and resharpen my carbide ones until half the teeth are completely gone, so long as the missing teeth aren't too asymmetrical.

[SidecarFlip]

I use annular cutters usually or the mill and a boring head but I have a set of Blu-Mol's which are just like your Milwaukee's. They work good so long as the speed of the drill is slow and you use plenty of lubricant. I see the Milwaukee mandrel is like the Blu-Mol. 2 extendable pins driving the hole saw. Thats the best way actually. You can get the hole saw off the mandrel with no hassle when you are done drilling..

Most times, I'm drilling plastic or rubber and you have to use a hole saw....

[n20junkie]

I have cut 1/2 stainless plate, countless 3/4 mild steel and so forth with a plain bimetal holesaw.

The key, go SLOW and use lots of coolant or lubricant. Clear chips with air from time to time and be patient.

Hole saws work great, especially at the 1 inch size. I have swung a 3in into 4130 with no problems.

All brands work well, but lennox seems to be my fav.

Slow

[shortfuse]

Thanks guys for the input on the hole saws.

REDONE, you mentioned Fastenal. Of all places out here in the sticks, we do have a Fastenal store. I might drop by there and see what they have.

I may try out a Milwaukee bi-metal first and if that doesn't do what I need to do then I'll probably get a carbide and be done with it. Wish the locals carried Lenox. Their hacksaw blades are tougher than bear sh*t...use them exclusively.

[jordan_5600]

I use annular cutters usually or the mill and a boring head but I have a set of Blu-Mol's which are just like your Milwaukee's. They work good so long as the speed of the drill is slow and you use plenty of lubricant. I see the Milwaukee mandrel is like the Blu-Mol. 2 extendable pins driving the hole saw. Thats the best way actually. You can get the hole saw off the mandrel with no hassle when you are done drilling..

Most times, I'm drilling plastic or rubber and you have to use a hole saw....

Yea having the pins that slide down to take the beating helps if you break a tooth off in there and have to back it out its even better!

[joshuabardwell]

Frankly, given the thickness of material you're working with, I don't think you need to over-think it very much. You're going to wear out the saw eventually. It'll last longer with higher quality, but at the end of the day, I would just buy what's convenient and then buy another one if I wore it out.

[shortfuse]

Got a Milwaukee today, will try it out first. Probably will be a day or two before I can get back out to the shop and drill press. Will post results. Thanks for the help, guys.

[nadogail]

Pin Drive saws in a hex shank mandrel are heads and sholders above the alternatives. My favorite brand of mandrels is Starret ( the micrometer company).

[VPT]

I'm not even sure what hole saws I have. They are yellow and red ones.

[shortfuse]

I'm not even sure what hole saws I have. They are yellow and red ones.

Correct answer!!! You win!!

[VPT]

Correct answer!!! You win!!

lol

I went out in the shop in -4f degrees to check what they are. The red ones are morse and yellow are starretts.

[shortfuse]

I'm just gonna to look for yellow and red ones...don't care who makes 'em (just joking...).

VPT, thanks for the manufacturer names. Still haven't been out to the shop to check out the "red" Milwaukees...other stuff going on right now

[shortfuse]

UPDATE: Finally tried out the Milwaukee bi-metal hole saw. Worked fantastic.

Needed to drill a 1" hole through an angle iron brace for holding rod and tubular stock so my drill bits would clear. Used a 1" Milwaukee bi-metal, on 1"x1"x1/8" angle iron tacked to 1/4" thick plate. Drill press @ 300 RPM, lubed. Went "slow & easy"...(that's what she said). The Milwaukee cut like a dream. Will stick with that brand until I have a problem. Thanks to all who offered suggestions for brands of hole saws.

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