Need Help With Hole Saw Notcher

[superskaterxes]

So i purchased a woodward fab hole saw notcher to do some fab work on my cars exhaust and i ran into an issue im hoping you guys can help with.

I have a set of Lenox hole saws which have served me pretty well and i havent had any issues with. I tried to cut a 45* angle in some 2.5" 309 stainless pipe and it absolutely destroyed the hoelsaw teeth. I then tried a slightly smaller hole saw and it did the exact same thing. Whats are you guys using in these notchers? I have a set of blair Holcutters but the arbor is different so i cant use them. All the picts online i see have people just using standard hole saws but apparently mine are no dice. I also tried some lube on the teeth as i was cutting with the second hole saw and that diddent seem to change anything.



Here is what i have for reference:

https://www.summitracing.com/parts/...3XYvHU4W_AnKC1Ae2BacD4ixpKcYXlpG75hoCk53w_wcB

 

[ptschram]

Use your chopsaw and throw that POS away.

Look up chopsaw tube notching on youtube.

If I didn't have a "Beast" and a mill, I'd be using a chopsaw or cut-off tool

 

[gungatim]

I don't have a notcher, but I think they use a big milling type bit for stainless...

I do know ss is a royal pita to drill in my experience.

I also second the chopsaw method. it works well if you aren't a production shop...

 

[jakemac]

Sounds like you're trying to use wood/drywall holesaws on stainless steel.
I think you need a diamond encrusted holesaw to cut stainless.

 

[Doug Arthurs]

A holesaw is basically a little bandsaw. I happen to own a company the sells and services bandsaw so I can help you out. When cutting mild steel a bandsaw should be running around 290 fpm when we changed to stainless we slow it down to under 100 fpm less then half the speed. The heat created cutting stainless kills blades thats why we slow way down. You need to run your holesaw as slow as you can. Another option is to buy a carbide tipped holesaw. I know Morse sells them not sure if Lenox does. You may have to find an industrial supplier to get one.

 

[b-dog]

Genuine question as I don't deal with much of anything directly related to this thread. I notch on a mill but that's rare and I never work with SS that's not machine grade 416.

Can you put an annular cutter in the notcher and do those work on 300 series SS?

 

[454ragtop]

With stainless, you need to slow the cutter way down, but keep up a pretty good feed rate. If you go too fast, the stainless work hardens and will kill the cutter. You need to cut it, not rub on it. What RPM drill are you using?

 

[Ign]

No one's accounting for the fact a hole saw is not very rigid and you're trying to cut a 45. Go too slow and the hole saw will just fold up. I've seen it happen on mills.

In this application a hole saw has very little in common w a band saw; a band is pulled tight under tension and can't crumple.

I don't have many great suggestions for you though. I'd:
1)try a different brand of hole saw (and not the Hole Dozers)
2) work out a coolant drip system using WSO
3) look for a way to adapt annular cutters
4) maybe try diamond hole saws or carbide tipped but it'll get spendy in a hurry

 

[Fcvapor05]

You can't adapt an annular cutter to that little hole saw rig- and you wouldn't want to.

An annular cutter takes a much bigger chip out of the work than a hole saw does. Think about how wide the teeth are on an annular cutter vs. a hole saw. That tube notcher is nowhere NEAR stiff enough for an annular cutter to work properly.

OP, you can notch stainless with that thing no problem. There are two keys to get it done.

1) You need quality hole saws. Lenox bi-metal saws are good enough- but if your set is older, non-bimetal Lenox they will die a quick death. You can try carbide if you want, but I wouldn't suggest it- carbide is super brittle, and your notching tool is not very stiff. To cut stainless successfully you need high feed rates. If the tool bounces or moves at high feed rates, the carbide will chip and your saw is ruined.

2) Stainless steel work hardens. This means that you have to take big cuts. If you try to go slow, the teeth will rub instead of cutting chips, and as soon as the teeth stop cutting the material will harden up and you're screwed.

Basically, buy a brand new hole saw, and when you go to make your cuts, turn the drill as slow as possible and use high pressure on the drill so that you're feeding the saw quickly through the tube. This sounds counter-intuitive, but it's what you have to do to cut work hardening materials.

 

[Mohawk Dave]

You can't adapt an annular cutter to that little hole saw rig- and you wouldn't want to.

Gonna disagree there. Cut the threads off my JD2 Tube Notcher shaft, bored a 3/4" hole, set set screws and run annular cutters. Kick *** all day and all night.



Now, you did say his tube notcher is not rigid enough for that, and that may be true. But assuming a notcher is rigid enough, then it is worth it.

 

[Ign]

Yeah that's just the NotchMaster clone. No reason to not adapt annular cutters.

OP you might as well get all the cool accy's for the NotchMaster from swagoffroad now (assuming they fit the WoodWard).

 

[Fcvapor05]

What I meant was that an annular cutter won't just bolt on. If you're comfortable with the machining, you can adapt anything to anything ha ha.

 

[ishiboo]

Try the Diablo carbide-tipped hole saws from HD. Run them slow, lots of coolant.