Thread: using lathe for mill

For starters will you be using Collets to hold your Slot Drill.
Make sure that your Vice is set Square in oth plans to your spindle.
You will probably only be able to take a mm at at time (DOC),depending on the Rigidity of your set up.
If the bar you are going to Slot is overly long or Heavy you may need to support the over hang from your vice.
Make sure you lock your Carriage when milling.
Take it steady and it shouldnt be a problem,just a little time consuming.
If you are going to use Power Feed on your Cross Slide use the Finest feed first see how that goes and work up from there.

Most lathes that accommodate milling slides have a slotted cross slide table .
But if your compound slide mount is solid enough then there is no reason why you couldn't use it .
The other option is actually fixing it to the cross slide ,maybe an angle plate that has edges on it that go below the top surface of the cross slide table and held by bolts (not drilled into the table) clamping from the side as per attached pic

Hi Gra,

I reckon a milling attachment would be a great asset, in the absence of a mill.

There are many tutorials on The Practical Machinist, in particular, one written by Paula.

She machined it up from castings available in the States, and although intended for the South Bend lathe, I've attached a link that makes interesting reading. Item #10

"http://www.practicalmachinist.com/vb/showthread.php/milling-attachment-sb-mla-173107.html?t=173107&highlight=MILLING+ATTACHMENT"

Somewhere in this section, is a complete article from go to whoa, written by her.

Nice to hear that the floods have subsided, and you now have some time on your hands.

Ken

Hi Gra,

Have you progressed any further with your thoughts of using your lathe as a substitute mill?

I can't believe there has only been a couple of replies to your Post, surely there are members out there that have improvised something, for a quick milling operation.

Ken

My lathe being a chinese type has no slots in the cross slide.

I am currently torn between Woodlee's idea on a clamp on for the cross slide and a 3 axis job that screws into the cross slide I found in a way back issue of popular mechanics.

I am also confused by the collet designations.

ER series seems to be the go but what's the difference between ER11 and
ER 32 for instance . And does an ER collett use a draw bar?

Is the 11 - 32 thing, a dimension indicator or something else entirely?

Another thing is that they can be purchased as R8 and 3m & 4m .I know mills can be either R8 Or Morse ,but aren't lathes only morse taper mount?

Grahame

not sure what the numbers indicate but the larger the number the bigger the cutter shank you can fit in them.
The collets either fit into a collet chuck with a tapered shank or straight shank to suit what ever type of spindle they are going into.They should require an arbor.
You can also buy or make an ER collet nut and retainer that will mount to your lathe spindle.

Originally Posted by Grahame Collins

My lathe being a chinese type has no slots in the cross slide.

I am currently torn between Woodlee's idea on a clamp on for the cross slide and a 3 axis job that screws into the cross slide I found in a way back issue of popular mechanics.

I am also confused by the collet designations.

ER series seems to be the go but what's the difference between ER11 and
ER 32 for instance . And does an ER collett use a draw bar?

Is the 11 - 32 thing, a dimension indicator or something else entirely?

Another thing is that they can be purchased as R8 and 3m & 4m .I know mills can be either R8 Or Morse ,but aren't lathes only morse taper mount?

Grahame

Grahame, I don't think being a Chinese lathe is the determining factor for not having slots in the cross slide. Mine is a Chinese made 9x20 and it has slots in the cross slide.

The drawbar is used on the ER chuck not on the collet.

The ER11, ER25 ER32 denotes the maximum size of the collets, but I don't know how the number relates to the max size. I have an ER25 set, it goes from 1-16mm in 1mm steps. From memory the maximum size for the ER32 is 19mm (3/4").

I thought some lathes had R8 and 5C headstock spindles, but not sure.

Grahame, do a google for ER collets, heaps of info freely available.

The size/diameter of the actual collet is what donates the numbering system with these type of collets, so an ER 8 is a very small collet and an ER 40 is a much larger collet.

http://www.arceurotrade.co.uk/Catalo...-Collet-Chucks

This type of collet, ER, is held in place by the collet nut, not by a drawbar, so you can shove a long bit up its guts.
Whereas a collet held in place by a drawbar, can only have something shoved down it's throat until it hits the drawbar, so only good for short bits.
You might have to make up a collet holder for your lathe, none to sure if you even have a thread on the spindle nose of your lathe.

If your going to do some milling on the lathe, then you will need something like this, to be able to do the milling, as it must be adjustable to get centre height.


http://www.chronos.ltd.uk/acatalog/C..._Table_71.html

If you find out that the costs will beat you, possibly check on a local engineering shop for a price to do this small job.

regards radish

i bought one of thesehttps://www.machineryhouse.com.au/Vertical-Mill-Slides
for my hercus but have not tried it but i know a few have

I've done quite a bit of milling on the lathe in the past. I just put the cutters in the 3 jaw chuck. You won't be able to take a big enough cut that holding them tight enough will be an issue. You could always put them in the four jaw, that will definitely hold them more than securely enough. If you're intent on getting an ER collet chuck consider getting one that is for a lathe, then you can pass bar stock through it for turning. The lathe ones mount on a backplate like a lathe chuck does.

A long time back I made up an angle plate out of steel plate that fitted where the topside does. I then arranged things such that I could put the topslide in the angle plate and used it as a verticle slide. I was pretty young at the time and didn't have money for anything better. I also had a t slotted boring table that I could swap with the standard crosslide. I haven't used any of that stuff in a very long time.

An option with some of the Chinese lathes that have the flat cross slides with no t-slots would be to drill and tap some holes at strategic locations. You could then bolt a piece of flat plate, with rows of holes drilled and tapped in it, onto the cross slide and thus obtain a useful boring table. You could plan it out so that a couple of the holes could also be used to mount a rear toolpost.

Minitech in Qld sell Myford style vertical slides. I think they're the best design, just my opinion.

Hi Ken I had a look at the link you supplied but I know I may end fabbing something from a heavy section flat and flat.

Turning a casting which will be bloody hard to get and not designed form my machine anyway, is just not my cup of tea.
I am leaning towards designs that are a multi plane axis adjustable,which I hope will work out to be 2 axis in the vertical and 1 on the horizontal.. Hopefully this can be accommodated on a piece of 150 x 100 x 25 angle.


GRAHAME

Originally Posted by tanii51

i bought one of thesehttps://www.machineryhouse.com.au/Vertical-Mill-Slides
for my hercus but have not tried it but i know a few have

yep i tryed.. but had no luck...
i own a H&F AL960B lathe... then a few months back, needed a quick fix solution and bought vertical mill slides and an 15mm slot drill bit, soon as it touched the job the saddle or that vertical slide moved a tad (play in tread) and broke the bit, shifted the vice and yeah wasnt pretty... might have another go one day when im in a rush again.

Originally Posted by Grahame Collins

My lathe being a chinese type has no slots in the cross slide.

I am currently torn between Woodlee's idea on a clamp on for the cross slide and a 3 axis job that screws into the cross slide I found in a way back issue of popular mechanics.

I am also confused by the collet designations.

ER series seems to be the go but what's the difference between ER11 and
ER 32 for instance . And does an ER collett use a draw bar?

Is the 11 - 32 thing, a dimension indicator or something else entirely?

Another thing is that they can be purchased as R8 and 3m & 4m .I know mills can be either R8 Or Morse ,but aren't lathes only morse taper mount?

Grahame

Grahame ,

The R8 taper is a proprietary taper designed by Bridgeport for thier milling machines and not used in lathes as far as I am aware .IMHO the morse taper is a much better taper for milling machines because the morse has a longer taper with more contact area than the R8 Bridgeport taper.

Of course there are many other tpaers used in mills like INT 30 ,40 and 50 to name a few .
The most common taper for lathe spindles and tail stocks is the Morse taper series .

The ER collets are a DIN Standard , used for holding milling cutters ,drills and also for holding round bar stock. If memory serves me correctly they range from ER 8 up to ER90 .
The number is designates the physical dimensions of the collet and what it can accommodate ER 40 starts at some where around 6mm and goes up to 25 mm.
The nut on the chuck is the secret to these collets ,there is an eccentric ring machined into the inside of the nut that fits into a groove on the collet and this clamps the collet itnto the chuck when you tighten it ,it also pulls and releases the collet when you unscrew the nut.
You can get them in metric and imperial , but a 19 piece metric set will cover all you need in metric and imperial.I was going to buy an imperial set as well but it's just being a tool junkie and I don't really need them .

I bought a 19 piece ER32 collet set from "onlineseller" on Ebay and two morse taper collet chucks to suit my lathe (MT2) and one to fit the mill(MT3).
The collets range from 2mm up to 20mm which is about the biggest endmill I would ever use.
Problem with the morse taper collet chuck in the lathe is
1. alot of over hang
2. you can't put long stock through the spindle because the hole is plugged with the taper and draw bar .

Since I have bought a screw on collet chuck from RDG in UK that screws onto the Myford spindle which allows long stock to pass right throug the lathe spindle .
http://www.rdgtools.co.uk/acatalog/info_86340LK.html.
Im not sure what yoiur lathe is but I think you can get the chucks on a modern type mount like the C 3 pin type mount as well.
I think Chronos in the Uk has them.

ER collets are much better than the old type collets for holding cutters because there are 16 splits (total) alternately front and back allowing the collet to collapse for it's full length onto the cutter shank,where as the morse and other types are split only at the front and only hold cutter shanks for a short distance along thier length. This can cause the cutter to run off center under load and create havoc (don't ask how I know this).

I would suggest either ER 25 or ER 32 or maybe even ER40 if you think you will use 25mm cutters.

Check "onlineseller" out on Ebay ,I have bought stuff from him and his prices are good and his postage is fair and reasonable.I'm very happy with the goods I have purchased from him and will continue to buy from him when he has stuff I need.

BTW don't use your three jaw chuck to hold end mills ,if the cutter jams you will ruin your chuck jaws if the cutter spins in the jaws , HSS up against a chuck jaw = damage.
Kev

Thanks Woodlee,
I guess I was trying to think ahead in case I ever got a Milling machine,I would not be keen on having to buy a second set.
Thnaks again
GRAHAME