# Arbors and Hole Saws for Tube Notching?



## erikmannie (Oct 2, 2019)

One of the main reasons that I bought my benchtop mill is to notch tubing. The first tubing that I have to notch is 1 1/4” inch diameter with .050” wall. You may know it as muffler tubing.

      I am new to milling, and I imagine that I will buy an 1 1/4”  holesaw. I have R8 collets for my PM-25MV milling machine. I haven’t bought a chuck yet because PM was out of stock for the chuck I wanted.

      When I was in school, the instructor used a hole saw that he attached to an arbor.  At school, they used a Bridgeport.  It was a bicycle frame building school, and the students were not allowed to touch the mill.

     All  of the hole saws that I see online are for use with a hand drill (3/8” shank).  Many hole saws online are bi-metal HSS.

Does anybody know of a product that could notch thin wall tubing with a mill?  What kind of arbor will I use? I want it to be thicker than 3/8”.


----------



## erikmannie (Oct 2, 2019)

It looks like I will have to tilt the head 60 degrees because the clamp in the V-block would interfere with the cutting tool if I put the workpiece at a 60 degree angle in the vise. At the school, they were constantly tilting the head back and forth to different angles.

It is painful to see that rusty tubing clamped onto the new V-blocks. When I make the cuts, I will clean the tubing.


----------



## erikmannie (Oct 2, 2019)

Here is the hole saw which uses a 3/8" arbor. I am not sure if 3/8" is rigid enough.


----------



## benmychree (Oct 2, 2019)

I have seen an R-8 arbor that screws directly into the hole saw; it may have been home made.


----------



## eugene13 (Oct 2, 2019)

I use hole saws in my mill doing the same thing.  Lennox saws seem to hold up better than the other brands and offer the best concentricity.  If you're looking for a dedicated tubing notching fixture check out the Old Joint Jigger.  You can build your own mandrel out of round stock by drilling and tapping a 5/8 18 or 1/2 20 hole in one end and using a short grade 8 stud. I have some pictures of the ones I built, I will post when I find them.


----------



## ErichKeane (Oct 2, 2019)

I've generally had terrible experiences with hole saws.  I might suggest going with an annular cutter.  They are significantly more expensive, but are much less likely to walk out on you, and will cut significantly more 'round' than a hole saw.

As far as tiling the head, you seem to have a rotary base on your mill vise.  Could you just use that to set the 60 degrees?


----------



## RapidTransit440 (Oct 2, 2019)

I'm using Blair/Hougen Holcutters,  the result with these things are amazing. AFAIK there is no visible wobble from runout that isn't related to my current "quality" chuck. No visible wobble on my hand drill (Has an upgraded aftermarket Jacobs chuck)

I've been eyeballing the Keyless Llambrich JK chucks Just an idea to look at, although depending on your machine and how much you want to spend you may want to look at Albrecht


----------



## erikmannie (Oct 2, 2019)

Here is a picture of the Ol' Joint Jigger in use. Thanks for that tip.


----------



## erikmannie (Oct 2, 2019)

I can't figure a way to get my rotating bench vise to get the 60 degree angle unless the head of the mill is tilted 90 degrees (as in photo above of the Ol' Joint Jigger).

I just bought a PM keyless chuck with an R8 shank. It accepts 1/8"-5/8" shanks.

I will check out Lennox and Blair/Hougen Holcutters along with annular cutters.

I will be making these which are used for practicing TIG welding on acute and obtuse angles in bicycle-sized tubing. At bike school (UBI), they called these "gruelons" because the students find the acute angles grueling to weld.


----------



## erikmannie (Oct 2, 2019)

Here is a Hougen that looks like it fits the bill. The picture shows the hole saw on its arbor. I would be surprised if the arbor is included for $14.85.

The arbor has three flat sides, so it would almost certainly fit in a drill chuck.


----------



## erikmannie (Oct 2, 2019)

And a Lenox that I will try. Looks like a standard 3/8" shank.


----------



## RJSakowski (Oct 2, 2019)

If you want to cut holes at other than 90º, you will need to make a jug/fixture to do so.  Angle iron would form a suitable cradle and a hginge and an adjustable brace would allow setting the desired angle.  It should be well secured to minimize shifting and vibration.  Cutting a hole at that angle will require a very rigid hole saw setup due to the extreme side forces at play.


----------



## RJSakowski (Oct 2, 2019)

If you use a hole saw2, I would predrill the pilot hole and use a dowel pin pilot rather than the pilot drill.


----------



## mikey (Oct 2, 2019)

You might consider a fine pitch roughing end mill and a swivel base for your vise if you plan to use the mill. An even faster way is a custom small wheel attachment on a belt sander - it will notch tubing in seconds.


----------



## erikmannie (Oct 2, 2019)

RJSakowski said:


> If you want to cut holes at other than 90º, you will need to make a jug/fixture to do so.  Angle iron would form a suitable cradle and a hginge and an adjustable brace would allow setting the desired angle.  It should be well secured to minimize shifting and vibration.  Cutting a hole at that angle will require a very rigid hole saw setup due to the extreme side forces at play.


This required rigidity is probably why the school used a Bridgeport knee type mill.

I will be making so many of these that it would be worth my time to make a fixture. That would be great if I didn't need to tilt the mill head so often.


----------



## erikmannie (Oct 2, 2019)

mikey said:


> You might consider a fine pitch roughing end mill and a swivel base for your vise if you plan to use the mill. An even faster way is a custom small wheel attachment on a belt sander - it will notch tubing in seconds.


My vise does have a swivel base, but I am not seeing how to use the swivel base to cut a 60 degree notch.

The benefit of a mill for mitering tubing for bicycle frames is that you end up with such a great fit up. The goal is a 0.1mm gap.


----------



## erikmannie (Oct 2, 2019)

Here is a 1 1/4" roughing end mill. I would have to see if I have an R8 collet large enough for that.


----------



## erikmannie (Oct 2, 2019)

This muffler tubing is CREW (Cold Rolled Electronically Welded). I will also be mitering 4130 chromoly between .020" and .050", Grade 2 Ti no thicker than .040", and aluminum (alloy and wall thickness TBD).

Definitely need to have the feeds and speeds dialed with as much rigidity as possible.


----------



## mikey (Oct 2, 2019)

If you plan to do a lot of cuts at odd angles then a 3-way tilting vise might be worth buying. They are expensive but will hold the work very securely for use with a milling cutter. Wilton makes one and I'm sure there is a cheaper import out there, too. 

At these prices, I would seriously consider a 2 X 72 belt sander with small wheel attachment. It would be an extremely useful tool for a fabricator to own. This will give you and idea of what I mean.


----------



## erikmannie (Oct 2, 2019)

mikey said:


> If you plan to do a lot of cuts at odd angles then a 3-way tilting vise might be worth buying. They are expensive but will hold the work very securely for use with a milling cutter. Wilton makes one and I'm sure there is a cheaper import out there, too.
> 
> At these prices, I would seriously consider a 2 X 72 belt sander with small wheel attachment. It would be an extremely useful tool for a fabricator to own. This will give you and idea of what I mean.


Wow, that tube notching belt sander in the video was making quick work of that tubing! 

I had not even realized that they made tilting vises. After buying the mill and lathe and paying for school, I will be out of money for the next year; also, my garage is stuffed.

What is the argument against tilting the mill head? Maybe a PM-25MV isn't rigid enough? I am about to find out.


----------



## ErichKeane (Oct 2, 2019)

erikmannie said:


> Here is a 1 1/4" roughing end mill. I would have to see if I have an R8 collet large enough for that.
> 
> View attachment 303181


That's actually a 2" roughing mill.  The 1.25 there is the shank.  I still recommend an annular cutter: https://www.homedepot.com/p/Drill-A...ERCH=REC-_-pipsem-_-304590100-_-304852936-_-N


----------



## benmychree (Oct 2, 2019)

erikmannie said:


> Here is a Hougen that looks like it fits the bill. The picture shows the hole saw on its arbor. I would be surprised if the arbor is included for $14.85.
> 
> The arbor has three flat sides, so it would almost certainly fit in a drill chuck.
> 
> View attachment 303179


That cutter would not work on tube as required, it is too shallow.


----------



## erikmannie (Oct 2, 2019)

At one of my jobs, I used annular cutters in a mag drill for holes in up to 2” plate. The pits are very sharp, and they do a great job.


----------



## erikmannie (Oct 2, 2019)

benmychree said:


> That cutter would not work on tube as required, it is too shallow.


The cutter should be every bit of 1 3/4” long. 

 Due to budgetary limitations, my first plan will be to tilt the head of the mill and use a long HSS hole saw with a 3/8” shank.


----------



## C-Bag (Oct 2, 2019)

My experience with tube notching was making a frame for my powdercoat enclosure out of 3/4" EMT. I used a HF notcher that of course needed quite a bit of beefing up and modding. I also used my benchtop drill press and what the whole process taught me was verticle is not the proper direction even with a tilting head. Something like the Ol' Joint Jigger or others like it is the ticket IMHO. I saw quite a few in race car shops. If I was thinking machine tool I'd go with a horizontal mill because then it would be easier to make an adjustable tubing vise. Or best of all build a really heavy duty joint Jigger style.


----------



## mikey (Oct 2, 2019)

erikmannie said:


> What is the argument against tilting the mill head? Maybe a PM-25MV isn't rigid enough? I am about to find out.



Other than the tedium of having to realign it afterwards, nothing. A tilting vise just makes things simpler and the index marks make it easy to reproduce angles. It isn't necessary and you can make jigs instead.

There is no doubt in my mind that if tubing work was a key focus for me, I would use a belt sander.


----------



## whitmore (Oct 2, 2019)

erikmannie said:


> One of the main reasons that I bought my benchtop mill is to notch tubing.
> All  of the hole saws that I see online are for use with a hand drill (3/8” shank).



You can get 1.25" endmills (roughing would be OK), even indexable carbide ones.   And an R8 shank 1.25"  holder
shows up on eBay for not much money.   It's likely that a three-jaw chuck and floppy arbor (like for a hand drill
operation) won't be as effective as just... a big hunk of cutter.

The tubes will come out better-looking if you put some aluminum soft jaws on the vise, and cut them into
C-blocks, then just mill your cuts through them (holding the tube with lower pressure over
a large area). rather than extending out from the vise.


----------



## pontiac428 (Oct 2, 2019)

I use hole saws for racecar/rock crawler stuff.  They do the job.  But if you're talking about notching a set of Tange Prestige triple-butted CrMo, you're gonna want better than 1/8" of precision.  For that, you'll want to buy annular cutters for the sizes of tubing that you will be joining.  You want those TIG welds to look even and straight?  (practice practice) you'll need to hand fit that joint together within a hair's width.  You can hide welds from your customers with bondo, but it would be better if you had perfect fishmouths to start with.  That's why annular cutters.


----------



## ErichKeane (Oct 2, 2019)

whitmore said:


> You can get 1.25" endmills (roughing would be OK), even indexable carbide ones.   And an R8 shank 1.25"  holder
> shows up on eBay for not much money.   It's likely that a three-jaw chuck and floppy arbor (like for a hand drill
> operation) won't be as effective as just... a big hunk of cutter.
> 
> ...


Fwiw: I made the mistake of buying one of those R8 1" endmills holders in eBay when I first started. 3/4" into my cut, it shattered and threw my endmills on the floor.  I've still got a bunch of unused 1" endmills I'll probably never use unless I need them in my lathe.


----------



## Ed ke6bnl (Oct 2, 2019)

I have a right angle attachment for my quill, that and a swivel vice seems like that would be a good choice with a whole saw of annular cutter


----------



## f350ca (Oct 2, 2019)

1/2 inch shank hole saw arbours are quite common. A 1 1/4 hole saw won't go through the tubing in one pass at an angle (may at 90 deg) you'll have to cut part way, then get rid of the top of the waste tube with a cut off saw or hack saw to finish the cut. It hangs up in the bottom of the saw. Best to tighten the hole saw on the arbour and not use the pins, Unless its tight against the arbour they wobble and cut oversize.

Greg


----------



## Asm109 (Oct 2, 2019)

I have used a lathe for tube notching.  Hole saw in chuck. Replace tool holder with a block with a hole that holds your tubing at center height.
It should have a slot and pinch bolt to hold the tubing tight.
Use the compound to set the angle you want to cut.
Works a treat it does.


----------



## RobertB (Oct 3, 2019)

benmychree said:


> That cutter would not work on tube as required, it is too shallow.





erikmannie said:


> The cutter should be every bit of 1 3/4” long.



benmychree is correct, the hougen hole cutters are for sheet metal. They only have a depth of cut of about 1/8".


----------



## Jason280 (Oct 3, 2019)

I've used bimetal hole saws in my Induma with box tubing, and its worked out pretty well...


----------



## machPete99 (Oct 3, 2019)

If using a hole saw for this do not use an arbor that has the locking pins, or at least do not use the locking pins, as they allow the cutter to wobble around and it will cut oversize. You want an arbor that screws in tight. 

Some of the commercial arbors have a relief groove that limits the thread engagement with the cutter. Using a washer here helps to keep it from stripping out.


----------



## ErichKeane (Oct 3, 2019)

In my experience, hole saws do really poorly if they hit the material at an angle.  I would expect any time you tilted the head that the side-load would mess up your cut.


----------



## bob308 (Oct 3, 2019)

check the racing magazines. there is a tool the is for notching tubing it uses a hole saw can be used in a drill press can set angles.  I have one it works well I built  many roll cages with it.


----------



## RJSakowski (Oct 3, 2019)

Here is THE way to cut your tubing.


----------



## ezduzit (Oct 3, 2019)

McMaster-Carr sells a very heavy duty hole saw arbor.


----------



## eugene13 (Oct 3, 2019)

We build a lot of things out of tubing in our shop; the black one is an IMCA modified, the naked one is a WISSOTA B-mod, we use the "Old Joint Jigger" for 99.9 of our copes, but sometimes we need to use the mill.  I built these arbors out of 1" CRS of unknown pedigree, I turned them down to 7/8" to fit my largest collet and not fit the 3/4" drill press.  I drill a hole and thread in a stud of the appropriate size.  I run them at 40 RPM with .0015 feed regardless of size.  A good hole will build two chassis and then some and it will give as good a fits as YOU are capable of making, and the most bang for your buck.
My argument for using hole saws;  I 1/2" high quality hole saw, about $15.00.  1 1/2" rotobroach, about $150.00, I haven't used up 10 hole saws since I bought the Joint Jigger back in '96.
the last picture is of the driver's side door bar, it's a compound angle and a difficult as you need to nibble a little off each end to get your width and I do it in the mill.


----------



## machPete99 (Oct 4, 2019)

Yeah, those shouldn't wobble around much!


----------



## eugene13 (Oct 5, 2019)

They do what I need them to do, and I treat them gently.  Here's a tip from the Ol Joint Jigger man himself, Dale Welch; When using a new hole saw the first time, dull up the teeth slightly with some emery paper, this will diminish


machPete99 said:


> Yeah, those shouldn't wobble around much!



the chance of it digging in and breaking the saw.  Been their done that.


----------



## erikmannie (Oct 5, 2019)

The advice to slightly dull the teeth on a new hole saw came just in time because I received my keyless chuck today from Precision Matthews. With the very last of my money, I picked up two Milwaukee arbors & three 1 1/4” hole saws from the local Home Depot.

Tomorrow I will try these 3/8” shank arbors in my new chuck on my PM-25MV milling machine.  I will make a video of the attempt and post a link here.

I remember that at school they used a hole saw for about five miter cuts, and then threw the holesaw away.  As I recall, they did not use the center drill.


----------



## f350ca (Oct 6, 2019)

I wouldn't recommend using a hole saw with a keyless chuck. The chucks are only rated to their opening dia, a hole saw will over tighten it to the point you'll need a pipe wrench to open it. Don't ask how I know.

Greg


----------



## erikmannie (Oct 6, 2019)

f350ca said:


> I wouldn't recommend using a hole saw with a keyless chuck. The chucks are only rated to their opening dia, a hole saw will over tighten it to the point you'll need a pipe wrench to open it. Don't ask how I know.
> 
> Greg


The chuck is rated for 1/8”-5/8”.  My plan is to use a 3/8” shanked arbor attached to a 1 1/4” hole saw.  So that could be a problem?

If I’m understanding correctly, you are saying that using up to a 5/8” drill would be okay, but that the longer lever of a 1 1/4” hole saw would exert too great of a leverage on the tightening mechanism.

Along those same lines,  I recently used a cheater bar on my bench vise handle to clamp the part tighter. This broke the cast iron beam in the vise and I had to buy a whole new bench vise.

I wonder how this plays into using a slitting saw (what with the relatively large diameter of the slitting saw). I know the RPMs are greatly reduced. I imagine that people put a slitting saw in a collet.


----------



## erikmannie (Oct 6, 2019)

So I decided not to risk abusing my new keyless chuck.

 I will get a keyed chuck for this job.


----------



## AlanB (Oct 6, 2019)

Seems like something more rigid than a drill chuck is desirable for this. A drill chuck is not designed for the uneven forces of cutting tubing at angles.


----------



## f350ca (Oct 6, 2019)

Good decision. I've often have the vibration and torque of a hole saw loosen the Jacobs taper on the drill chuck as well. For a slitting saw you want as little runout as possible, or one side of the saw does all the cutting. I've only ever used them with a collet.

Greg


----------



## erikmannie (Oct 6, 2019)

I bought a (max) 1/2” keyed chuck from Little Machine Shop.

   My options are a limited now because I will be very much out of money for at least 6 months.

      I wish I could remember exactly how they chucked up the hole saws at United Bicycle Institute. I am positve that they used the bimetal hole saws for all of the miter cuts.  All of the material was 4130 chromoly tubing with .020”-.040” wall thickness. All of this was on a Bridgeport knee type mill, so you know that is rigid enough for any variation of this task.


----------



## ttabbal (Oct 6, 2019)

I think I would make or buy an arbor with a round shank and put that in a collet.


----------



## AlanB (Oct 6, 2019)

something like this:






						Hole Saws and Arbors - Pvdwiki
					






					www.peterverdone.com


----------



## erikmannie (Oct 6, 2019)

AlanB said:


> something like this:
> 
> 
> 
> ...


Wow, I  will definitely pursue getting an arbor to use in an R8 adapter.  

Thanks for posting that link!  It was chock full of insightful tips.


----------



## nnam (Oct 7, 2019)

Using hole saws without two safety pins/lock pins, or whatever it is called can be dangerous because they can spin out of the hoder and you got sawed!


----------



## Jason280 (Oct 10, 2019)

> I wouldn't recommend using a hole saw with a keyless chuck. The chucks are only rated to their opening dia, a hole saw will over tighten it to the point you'll need a pipe wrench to open it. Don't ask how I know.



I recently learned this myself...


----------



## kb58 (Oct 10, 2019)

I designed and built two tube frame cars from scratch (www.midlana.com and www.kimini.com) using the typical tube notcher and hole saws. It worked fine, but was messy, the cutters are not intended for use on curves surfaces, and quality control was only "meh." That last bit means that the hole saw usually wobbles or has some offset. As a result, the end product isn't as precise as it could be—but the reality is that it usually doesn't matter due to all the other variables involved. The only real issue is the course pitch of the teeth; if someone started making fine-pitch hole saws, there's probably enough business that it would be viable.


----------



## erikmannie (Oct 10, 2019)

kb58 said:


> I designed and built two tube frame cars from scratch (www.midlana.com and www.kimini.com) using the typical tube notcher and hole saws. It worked fine, but was messy, the cutters are not intended for use on curves surfaces, and quality control was only "meh." That last bit means that the hole saw usually wobbles or has some offset. As a result, the end product isn't as precise as it could be—but the reality is that it usually doesn't matter due to all the other variables involved. The only real issue is the course pitch of the teeth; if someone started making fine-pitch hole saws, there's probably enough business that it would be viable.



I found 10TPI (teeth per inch) from a company called RockHardToolz. I bought two bimetal hole saws in 1 1/4” diameter.

MSC and a cursory Google search only turned up 4-6TPI, most of which were variable pitch.

I also bought three different 3/4” shank hole saw arbors which was all that the internet seemed to offer. I will post pictures of them when they arrive.

When I was in bicycle frame building school, I thought that there might be a consumer demand for thin tubing cut at a 60° angle for people to practice TIG welding. When these miters are cut on a mill, you have to clean/fit them up with a hand file and Emery cloth. The muffler tubing is cheap enough; maybe somebody could do this as a side gig.


----------



## stupoty (Oct 10, 2019)

machPete99 said:


> do not use the locking pins, as they allow the cutter to wobble around and it will cut oversize. You want an arbor that screws in tight.




I stopped using the pins on the hole saws in the mill or drill press and have found them much better on both.

Getting them off is sometimes fun 
I vice up the arbour and use metal "sticks" in the slots in the walls of the cutter.

Stu


----------



## savarin (Oct 10, 2019)

I have used bimetal hole saws for heaps of angle and off set cutting in steel when I was building recumbent bikes.
This wall and some thicker square tube.
Sometimes using just the power hand drill and sometimes the drill press.
Occasionally it cut oversize but then I just filled the gap with weld.
Most of the time it worked with no problems.
I've also used giles tube mitre program and cut the tubes and filed by hand.








						Tube Miter Program by Giles Puckett | Rorty
					

A tube mitering program for Windows to print on any printer. This program deals in metric units.




					rorty.net


----------

