# Cutting wheels on a drill press



## Amber (Jul 29, 2011)

In my continuing adventures of attempting to cut railroad wheels using my drill press, a cross slide vice, and a lathe cutting tool, I've discovered a number of things that don't work and a few things that do work. 
I've discovered that steel is difficult to cut using the drill press. There's too much vibration of the cross slide vice to get anything like a smooth finish on the wheel tread. I had to use a big mill file to smooth the tread while spinning the wheel, that also works for the flange. 
My drill press has an MT-2 shaft for the drill chuck, and that has a habit of coming loose when you put downward pressure on the work piece, creating a bit of havoc when it drops out of the drill press.
I made a 5/16ths arbor from a bolt to mount the wheels on, that turned out to be not big enough diameter to keep from bending while cutting 2-1/2 inch diameter steel wheels. It took a while, but it eventually bent just enough to give the wheel a wobble while trying to finish cutting it. I managed to get 3 of the 2-1/2 inch diameter by 3/8ths thick wheels cut, it bent on the 3rd wheel, but I didn't have enough steel for the 4th one anyway. I need to get another piece of 3/8ths by 2-1/2 inch bar stock for the 4th wheel to finish the set.


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## Amber (Jul 29, 2011)

A couple of weeks ago I ordered a set of 8 aluminum disks from a seller on ebay that are 4 inches diameter and 1/2 inch thick, I want to make a set of wheels for my 2 inch scale Gilpin Tram caboose. Without the wheels and journals, there's not much point in going any farther with the caboose project, and pre made wheels are just too expensive for me. A set of wheels for the caboose would probably cost around 100 bucks.
Anyway, I made a new arbor to mount the wheels on for cutting, this arbor is 3/8ths diameter, made from a 1/2 inch bolt. The bolt was 3 inches long and threaded half way to the head. I cut the head off the bolt, chucked it in the drill press, and cut the threads off with a coarse file while spinning the bolt. Then I cut the bolt down to the 3/8ths thread diameter, measuring with a micrometer as I went along, and then threaded it with a 3/8ths coarse thread. I left about 3/8ths of an inch unthreaded at the end of the cut down part, and cut a square shoulder on the end of the cut down part for the wheel blank to snug up against.
I've started working on the aluminum disks, I must have done something right on the arbor because there's almost no wobble in the disk when it's spinning. I tried to drill the hole in the middle of the disk as square as possible so that it would run true when mounted.
I had been trying to do all the cutting for 1 wheel but decided to do the facing on all 8 disks first before I cut the tread and flange. Dishing the face of the wheel is "interesting" with this setup, I can't get a curved dish with this setup so I'll have to settle for a flat dished out area. It's better looking than not dishing the wheel face.
I will say that the aluminum cuts nicely with a high speed steel bit in the lathe tool and WD-40 for lubricant. I can just spray the WD-40 on the piece.


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## armorsmith (Jun 1, 2008)

Amber,
I am not surprised at the difficulties you are experiencing with your wheel cutting adventure. Primarily because you are using the wrong tool for the job. These types of tools are somewhat 'design specific'.
The reason you are experiencing 'chatter' in cutting the steel wheels is the drill press is not designed for horizontal pressure against the spindle. The drill press is designed to spin a drill bit at a given speed, determined by the size of the bit and the material being drilled, and axial pressure vertically along the axis of the spindle.
The morse taper on the chuck is designed to get tighter, the more pressure you put when drilling. The combination of chatter and down force you are exerting doing whatever operation it is you are performing is a combination that will disengage the chuck from the spindle every time.
Using a bolt as a spindle for turning wheels, regardless of tool, will most likely result in a 'wobbly shaft', a standard bolt is not hardened or heat treated and therefore will flex. Bolts are designed to be primarily used in the tension condition (pulling along the axis of the bolt), and to a lesser extent in shear (across the bolt). Bolts are not designed for a bending condition.
Aluminum being much softer material than steel will most likely allow you to do what you are trying to do, but be that as it may, a drill press is not a lathe. A lathe is the tool you need to be using.
Bob C.


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## Amber (Jul 29, 2011)

I agree with you, Bob, but I don't have the 600-800 dollars necessary to buy a small lathe, so I'm pretty much stuck with doing this with the tools at hand. I realize that it's probably not too good for the spindle bearings on the drill press, but it's either use the drill press or not cut the wheels. The aluminum seems to be a lot easier on the drill press than the steel wheels were, so that's a good thing anyway.


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## armorsmith (Jun 1, 2008)

Have you considered searching the net for a Job Shop that might do the turning for a small fee? Take a look in Thomasnet (I think that is how is goes) and search for machining. It can't hurt to make a couple of phone calls.
You could also have posted on the fora to see if a fellow modeler would be able/interested in doing the machine work. Another option is another forum called something like "Home Machinist", someone there might be able to help.
Bob C.


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## Homo Habilis (Jul 29, 2011)

Another option might to see if your local High School or Junior College has some type of machinist course. Some of the ones in the Bay Area offer adult extension classes that, for a token enrollment, will allow reasonable access to this type of equipment.


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## Totalwrecker (Feb 26, 2009)

I wonder if you couldn't attach a live center, I hope that is the right term, what I'm picturing is a spike on a bearing, to the bottom face of your drill press. Used as a center pivot you could use down force to keep your arbor up in the taper. Perhaps a bag of shot on the handle, would keep it snug enough....

I thoroughly enjoy repurposing tools.

John


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## SD90WLMT (Feb 16, 2010)

I wish you could post a photo of this process...showing the cutting tool angle...

Possibly this might reveal a reason for the chatter you experience....

Dirk


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## Semper Vaporo (Jan 2, 2008)

She posted a couple of photos in a previous thread:

http://forums.mylargescale.com/30-tools/31322-new-drill-press.html


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## BigRedOne (Dec 13, 2012)

I like the local college option myself - could be a lot of benefit to that, beyond access to a specific tool.

Short of buying more tools, or finding a machinist, how about an auto repair shop? A machine for resurfacing brake rotors might work (though labor rates might not.)

Do you have a small bench grinder? Might be able to mount the wheel blanks to the grinder's shaft.

Last (and this seems tacky, but might be nearly invisible in operation), buy two pieces for each wheel - e.g., wheels at 3.75" x 3/8", and a separate piece at 4" x 1/8". Attach them together, and you have the rough shape of a flanged wheel without needing to remove nearly the amount of metal.


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## SD90WLMT (Feb 16, 2010)

Thanks Semp...

One pic...
Hard to tell position of cutting point relative to spindle turning center....
I'm sure the cutting tools face edge is not in contact..but just the point...

It is a matter of just where that point contact touches the material.....

Dirk


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## SD90WLMT (Feb 16, 2010)

It needs to be hitting a point perpendicular to the piece thru the center line of turning...
And ...a touch...or 1 1/2.... touches after this point..in the direction of rotation....

I.e. ...trailing the point of perpendicularity.....

D


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## Amber (Jul 29, 2011)

I have the point of contact of the cutting tool lined up with the center of rotation as best I can eyeball it. I can adjust it for point of contact with the cross slide. I read something on line that said that the tool should be as close to center of rotation as you can adjust it with the lathe tool holder, so that's what I was trying to do. I could try adjusting it slightly past perceived center to see how it cuts. 
I'll post a couple more pictures as soon as I get them loaded onto the computer from the camera tomorrow.


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## SD90WLMT (Feb 16, 2010)

The point of my message is this...

Everyone is saying a lathe needs to be used for the best results...
...but ..even if the proverbial lathe is used....

IF....not set up properly..even on a lathe...one can still get chatter...as a result of improper cutting tool placement...

Cutting point position...
Cutting tool sharpening.. how sharp ...shape of cutting edge tip...
There are many reasons for chatter...

...and not all the fault of using a basic drill press...

Frankly ...I'm surprised more of our machinists in here have NOT added their knowlegde to this conversation....

Keep trying Amber!!!

...Dirk


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## SD90WLMT (Feb 16, 2010)

OK...I looked at the picture again....

Amber...it appears you may also be able to loosen and "choke" the cutting tool a bit shorter in the tool holder....

Shortening the distance will act to "stiffen" the cutter..also reducing the potential for causing chatter....

Do not have it any longer than needed to insure that the tool holder itself will not strike the work...usually at some deepest cutting point....

Finding a local "mentor" that can eyeball your work would be great..! ?

Dirk


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## TrotFox (Feb 15, 2008)

Amber,

Here's a potentially dumb question... Have you tuned the ways on your XY table yet? Any slop there would allow lots of ugly chatter. On my cheap 3-in-1 I sometimes have to slightly tighten the table locks to overcome chatter by providing that little extra rigidity at the cost of extra force needed at the feed handles.

Good Luck!
Trot, the make-shift, fox...


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## Amber (Jul 29, 2011)

https://flic.kr/p/nuwMDc

I used to know how to get the picture to show up, but then Flickr changed their format, and now I can't find the proper code for that.


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## Amber (Jul 29, 2011)

The cross slide vice that I was using for cutting the steel wheels is a cheap one that has several areas of looseness. I tightened the tension screws on the ways, but it still has looseness. I'm using my old cross slide table with a drill press vice on this set of wheels, this setup has a lot less looseness to it. I've had very little chatter with the current setup. It's possible that cutting aluminum instead of steel has something to do with that also.


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## machiningfool (Nov 15, 2008)

I agree, you are using the wrong tool. I think everyone agrees on that. If you look on Ebay or Craigslist, you can find a small used lathe for between 200 and three hundred dollars, a good investment for anyone making there own parts. I have bought seemingly worn out lathes for those prices and they still do acceptable work. I have also installed a treadmill motor on my lathe and the variable speed makes it a very smooth tool. Robert Brown


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