Question for all you guys out there building cages or using tube notchers. How do you get your hole saws to last?? Im building a chromoly cage right now in my supra, and my hole saws are only lasting 5-6 notches and then they are done.

Im using a bi-metal holesaw from home depot. Retails about 20$ and ive already went through 3 of them on one cage. Im using wd40 to lubricate it as i cut, and im using my corded drill at full tilt. Seems to cut very well, the hole saw just doesnt seem to want to last very long.

Ryan

 

Cutting fluid

 

Lenox Band-Ade Sawing fluid is what we use here

 

I use seman

 

Corded drill at full tilt? That's way too fast. A 1/2" corded drill with lots of torque so you can slow it down a bit is the key.

I cut 2" holes in stainless collectors for wastegates using bimetal holesaws and they last forever.

I also use cutting PASTE/STICK, no fluid. Fluid tends to sling off the holesaw, what you want is Do-All or Walter cutting stick, it's more like wax.

 

Yeah I was about to say that full tilt is way too fast to be cutting through steel with those blades. I would go about half-1/3 of the speed you currently cut at.

Bondo I haven't heard of cutting paste. I'll have to find some and try it out.

 

I agree that slowing the drill speed down is better for the bit, however, I ran into problems snapping the teeth off of the bit doing so. I use a lot of cutting fluid and I just go full tilt now and I haven't broken any teeth off since. So far the life of the saw hasn't been noticably diminished either. There's a local hardware store that i go to for replacement saws that accepts core exchanges with the purchase of the new saw. I'd look for a place that offers this. It's not uncommon and it keeps the saws in the $8-$9 range.

 

I'm using a Harbor Freight notcher and Harbor Freight 1/2" drill at about 3/4 speed. I've probably cut 50 notches with the same Home Depot hole saw without issue. I only lube it if I have a spare set of hands. If I'm doing it alone, I don't bother.

 

I bought a Lenox carbide hole saw for like $45. Cuts through all metals like butter, I used to get 2 cuts on a bi metal one when drilling wastegate holes. Now, Ive done like 10 or 12 and saw cuts like new still.

I also use it at the slowest speed my drill press will go and use oil to cool.

 

Sounds sweet, I am a ***** for anything that has carbide.

 

i use a Milwaukee 1/2 corded drill when doing tube notches.sometimes i use the stick wax other times cutting oil.very slow speed.the key to not knocking teeth off is to watch for when the cutter is starting to break through.back way off and let it knock the piece out.i can make a 1 1/2 inch hole saw last for a very long time.i bought this drill just for doing notches.i had a cheep skill brand drill and it ripped the gears right out of it from breaking though on a cut.

 

morse bimetal hole saws form grainger. 1 hole saw will generally cut and notch 3 subframes for me which is 30 notches per unit.

I use to use the home depot ones but the morse units from grainger are basically the same price and last much longer

 

http://www.vansantent.com/tube_copin...ng_notcher.htm

we use this guy. have had it for four years now and haven't had to sharpen the bit yet. we usually use a little wd40

 

WD 40 may not be the absolute best lubricant, but I just can't part with the smell. It's so much better than PB blaster

 

haha, never used that stuff. i can tell you that wd40 increases our bandsaw blade life by about 3 months

 

Like mentioned above, if i slow the speed down of, it tends to break the teeth off the whole saw. I have cutting wax at work, so i might snag some and try that and reduce the speed. Im also cutting chromoly steel which is a pretty tough. I dont expect the whole saw to last forever, but ****, maybe 15-20 notches would be nice when your paying 20$ a hole saw.

Im using a 1/2" drill on a jd2 notcher. So far i have zero complaints with the notcher, just have to get the hole saw issue figured out. Thanks for the tips, ill try it out this weekend and see how it goes.

Ryan

 

they make a bit that looks like a die grinder burr, but its large and used for notching tube. believe me, get one and you will never need to use a hole saw again. we tried the hole saw bit thing and it got old very fast.

of course this if for notching tube, wont work for cutting out the wastegate hole or anything where a hole saw is used.

 

I use Pro Tap cutting fluid. Stinks to high hell. Smells like burnt cat ****, but it will keep a hole saw alive. I have a Rigid 1.75 hole saw that I have been running for two+ years. Done 4 or more cages with it. Was using a drill press, now I am using a 1/2in Dewalt drill that turns really slow, max 900rpm, but that monster has enough torque to break your wrist. Works great. I picked up some holesaws last month for cheap. No name brand made in USA, but first cut it stripped all the teeth off. Not impressed.

The key is to go slow and let the saw cut, don't force it. If it binds, stop. Use plenty of cutting fluid.

 

You need to spin them at the proper speed, spinning them too fast will dull the teeth, spinning them too slow will not break teeth, breaking teeth is caused by lack of proper fixturing, if the parts or the hole saw is moving around you will break teeth. Also not all holesaw arbors are created equally, a holesaw should not have any play when it sits on the arbor.
Use good quality holesaws like morse or lennox.
And again, SPEED, use the right one. For a HSS bi metal holesaw cutting SS material with a 1.5" holesaw you should be turning it at 115rpm.

 

Something that someone else touched on is the pressure. When I'm notching, I don't put any force into it. Just the weight of the drill and a little just from the weight of my arms. Nothing more. It takes some time to bore through a pipe, but I've never chipped a tooth on one of my hole saws.

 

Maybe im just pushing way to hard, because it literally only takes me 20 seconds to bore though a 1 5/8" piece of chromoly. Like i said i had the drill at full tilt and i was pushing pretty hard :D.

Ill try backing it off and slowing it down a bit. Im going to try it later tonight with some cutting wax. thanks for the help guys!

Ryan

 

You should have good pressure on the holesaw, if you don't it will rub instead of cut and wear your teeth out, your biggest problem sounds like lack of rigidity and improper speed.

 

It's an end-mill...not a bit...

 

Yeah, we have a notcher at work that takes endmills. It's a simple setup that one of the guys made here. I would say you get a few hundred notches out of each one. Lots more if you use oil or wax.

 

The only downside to using a roughing mill as a notcher is that you can't do the thin material (.065-.050 and under). They will collapse the tube.