Hole saw wobble?

[MillerMav]

Good morning all!

Over the weekend I finished up my weld cart and finally got to try out my Milwaukee hole saw kit. I purchased it a couple years ago with an HD gift card but never used it.

That being said I used the 1" on some 2x2 1/8th mild steel tube in my drill press. The starter bit cut fine but as soon as I applied pressure to the hole saw it wobbled something fierce creating a hole that was probably 3/16 oversize. It wasn't a big deal because I was welding the round stock to the square and just wanted to sleeve it for strength.

All that being said; is this normal? Was my speed to slow or too fast on the press? I tightened the saw to the starter bit but was that not tight enough?

Any help would be appreciated.

 

[mooseye]

In my experience, slower is better with a hole saw.
Start the cut with very light pressure till you have a kerf established. This will help guide the saw.
Use some type of coolant/lube. I use a cap full of cheap dish soap in a quart of water.

 

[A_Pmech]

Not all hole saws are equal. Good hole saws have a 1/4" plate back which provides a flat surface for the arbor to mate against.

That said hole saws are very much a roughing tool. They all run out to varying degrees. If you need an accurate hole an annular cutter would be a better choice.

Speed for a 1" hole saw should be in the neighborhood of 225-300 RPM with a solid setup in mild steel with cutting oil.

 

[csp]

I've found that once the pilot hole has been cut it helps to replace the bit with a piece of 1/4" round stock. The bit will continue to enlarge the pilot hole, allowing the hole saw to wander and this doesn't happen nearly as bad with round stock.

 

[astroracer]

If I have some off hand holes to drill I make a drill guide out of a scrap piece of lumber.

After a while you will have a few of these drill guides on hand.
This works for both hole saws and annular cutters. Saves a lot of headaches trying to cut a nice hole with a wobbly cutter and works especially well with thin stock.

Mark

 

[raddksn]

If I have some off hand holes to drill I make a drill guide out of a scrap piece of lumber.

After a while you will have a few of these drill guides on hand.
This works for both hole saws and annular cutters. Saves a lot of headaches trying to cut a nice hole with a wobbly cutter and works especially well with thin stock.

Mark

that's slick !!!!!

 

[McLean]

x2 on the previous comments. HUGE variation in hole saws, but most of my experience is limited to Home Depot hole saws (Rigid and now Milwaukee), but I have used a few Lennox saws with similar results. As always, rigidity is your friend. If you can clamp it in a drill press or mill, you will get much better results. Also, don't use any of the quick change arbors (unless you remove the "quick change" portion), they allow the hole saw to be loose on the threads. I prefer to use a standard 7/16" arbor with a washer sandwiched between the arbor and the hole saw, then clamp it tight in the drill press. It's not perfect, but I'd say that the results are closer to about 1/16" runout.

 

[sberry]

I can get them pretty close, even align some holes.

 

[sabercatt]

dont forget to cut a piece of foam first with your hole saw and leave the foam plug in the hole saw. fill it with cutting oil and it will self lubricate while it cuts.

 

[sberry]

That is a slick idea.

 

[Ign]

AP Mech's info is of course great but if in doubt, spin it faster. When trying to notch tube especially where only one part of the hole saw is touching the work they'll simply fold up if you spin too slow.

I realize this is not what you were doing so I'd say your problems were due to one of three things:
1. the hole saw or arbor is jacked up
2. spinning too slow
3. your drill press is very sloppy, cheap chuck, spindle was near full extension, etc

3/16" on a hole saw is excessive, I can generally hold 1/16" and no more than 1/8"

 

[Ign]

oh and of course it should be mentioned quality problems or runout issues can compound, ie if your hole saw was not the most concentric from the factory 'cause it was made on a Friday afternoon, coupled with a drill press that is less than industrial quality coupled with, say, too much spindle exposed thus making the machine even less rigid................all adds up to what you got, while any ONE of these issues ALONE would have been much less of a concern.

 

[McLean]

dont forget to cut a piece of foam first with your hole saw and leave the foam plug in the hole saw. fill it with cutting oil and it will self lubricate while it cuts.

GENIUS.

I know nothing about foam. Any suggestions?

 

[Richard D]

dont forget to cut a piece of foam first with your hole saw and leave the foam plug in the hole saw. fill it with cutting oil and it will self lubricate while it cuts.

Good idea, but is it enough lube? I keep a spray bottle with self-mix cutting oil in it, I like a LOT of lube! It's way cheaper than cutting tools.

 

[Sureshot]

If you need tighter tolerance you can run one size under and fit as needed.

 

[rockwithjason]

i use these, love em

ideal carbide hole saw

 

[shawnspeed]

I was introduced to "aviation" hole saws, and was hooked...Roto- broaches from Blair/ Hougen are also a fav for smaller holes...the aviation hole saws are not cheap...but they do work great, and are always true...I keep adding whenever I can, and or need a new size...http://www.spenro.com/fine-tooth-hole-saws-p-431.html
http://hougen.com/cutters/sheetmetal/Rotacut.html

 

[Adam McLaughlin]

AGREED,
Hole saws a rough cut tools at best. I use mine to make holes in office desks to pass wires through, etc.
Cut wood with them, pass wires through siding, cabinets, you name it.

Cut precision holes in steel? I use the Water Jet at work
Adam

 

[ilovevocs]

I was introduced to "aviation" hole saws, and was hooked...Roto- broaches from Blair/ Hougen are also a fav for smaller holes...the aviation hole saws are not cheap...but they do work great, and are always true...I keep adding whenever I can, and or need a new size...http://www.spenro.com/fine-tooth-hole-saws-p-431.html
http://hougen.com/cutters/sheetmetal/Rotacut.html

Those look like like a much better option than hole saws for the price. Annular cutters are sweet, but its hard to justify the $$$ for me. I end up roughing with a hole saw and bringing the hole to size on the mill with the rotary table when the applications call for precision. It's allot of setup / steps for one hole, but it works.

 

[ez-duzit]

Operator error?

You should be using an arbor that looks like this:

Proper installation means threading on the hole saw until it bottoms out, then backing off until the dowels can be fully engaged. Run at slow speed with lube.

 

[rlitman]

Operator error?

You should be using an arbor that looks like this:

Proper installation means threading on the hole saw until it bottoms out, then backing off until the dowels can be fully engaged. Run at slow speed with lube.

That's the larger sized arbor. It will not work on a 1" hole saw.
The smaller arbor does not use dowels.

 

[spooler41]

I managed to buy a large assortment of annular cutters, before Boeing closed there
surplus store in the Kent valley. I sure miss that place, but I did stock up before they closed it, got about 250# of assorted drill bits,several hundred # , of mill cutters and
other machine tool tooling.

........................Jack

 

[ez-duzit]

Ah, missed the 1".

One trick that makes for faster, easier hole sawing is to barely start the hole saw, just to mark the cut; then drill a 1/4" hole right on the cut line. It helps clear the chips.

Check to see that the drill press table is square to the chuck.

 

[SteveBausch]

Yep, a zombie thread....please forgive me.

Regarding the wobble with hole saws, when the drill press has a Morse Taper socket, and the hole saw has 1/2-20 threads, I would consider a Morse Taper arbor with 1/2-20 threads (intended to mount a drill chuck). Plenty of them to be found on ebay.

You don't really need the starter bit (when using a drill press) if the hole saw is running true.

Regarding the larger saws with 5/8-18 threads (NOT 5/8-16), you'd be obligated to purchase a Morse Taper blank and drill tap it for 5/8-18 stud.

Unless you pin the hole saw in place with bolts or screws, the hole saw and the arbor will most likely become a permanent assembly.

 

[Ed ke6bnl]

Yep, a zombie thread....please forgive me.

Regarding the wobble with hole saws, when the drill press has a Morse Taper socket, and the hole saw has 1/2-20 threads, I would consider a Morse Taper arbor with 1/2-20 threads (intended to mount a drill chuck). Plenty of them to be found on ebay.

You don't really need the starter bit (when using a drill press) if the hole saw is running true.

Regarding the larger saws with 5/8-18 threads (NOT 5/8-16), you'd be obligated to purchase a Morse Taper blank and drill tap it for 5/8-18 stud.

Unless you pin the hole saw in place with bolts or screws, the hole saw and the arbor will most likely become a permanent assembly.

I do like this idea and my check into getting a MT3 for my drill press will also fit the tail piece of the lathe.

 

[PugetDude]

I managed to buy a large assortment of annular cutters, before Boeing closed there
surplus store in the Kent valley. I sure miss that place, but I did stock up before they closed it, got about 250# of assorted drill bits,several hundred # , of mill cutters and
other machine tool tooling.

........................Jack

I really miss Boeing Surplus. I still use a few countersinks, riffler and vixen files, drill bits, plastic mallets, etc. that I bought there over 15 years ago. It was a great place to buy tooling and small shop supplies.

 

[kbs2244]

The right tool for the job.
In this case both the bit and the drill press.
9 time out of 10metal means slow speed.
Even if notching.
You just feed slow also.

As said, big box hole saws are meant for wood in a building construction end use.
They are not precision tools.

 

[RogueFab]

Some hole saws are better for metal than others. Starrett, old (all white) lenox, irwin, old milwaukee ones (I haven't tried any new ones). Those are all pretty good on metal and around $10 each, some more.

Those arbors with the pins allow a lot more wobble and movement than any other arbor. They are designed for easy removal, and they're great for that.

 

[Dirtydan69]

I can get them pretty close, even align some holes.

That's one fine drill ya got there. I love my Milwaukee 28V tools.

 

[jimbbski]

For holes of 1 inch or less in thin material I prefer to use a step drill. If the material is thicker then sheet metal like 1/8 steel you can use a normal drill bit and then finish it with the step drill.

I also always use a hole saw smaller then the hole size required due to the run out they all seem to have. Even when I have mounted one in my lathe to cut a large hole I still got some degree of run out, just not as much.

 

[dutchgray]

Also worth mentioning that the Bosch quick change hole saws can be put straight in a DP chuck with no arbor as they have a hex base.

 

[davewo]

ACE hardware saws have an integrated hex shank and I've used them extensively on my milling machine. I did have to repair the one pictured below by welding on a solid shank, but it made a lot of cuts before then.

View media item 56391

 

[FANTM58]

If I have some off hand holes to drill I make a drill guide out of a scrap piece of lumber.

After a while you will have a few of these drill guides on hand.
This works for both hole saws and annular cutters. Saves a lot of headaches trying to cut a nice hole with a wobbly cutter and works especially well with thin stock.

Mark

This set up works great if you want to cut disks with out holes, just remove the arbor bit ..