Questions regarding CH-10M mill

Hey everyone, just a quick introduction here. I call myself Ignatz and live over here in Belgium. Just getting a bit deeper into the world of machining, but still pretty much in beginner territory. I've had a little Taig lathe for donkey's years and finally decided to take the plunge and get something to handle the milling work.

This is a small vertical mill/drill unit I purchased some weeks ago. It is a CH-10M unit, made in Taiwan and dates from 1999. It is in surprisingly good shape for its age. The motor runs well and the carbon brushes don't appear to have any appreciable wear. I also think the previous owner loved lubrication… maybe to a fault. The mill came with a fair number of end mills, reamers and such and now I am in the process of acquiring some of the necessary tooling to complete this unit.

Anyway, I have a few questions.

A) This unit does not have the optional fine feed wheel (photos B, C). This can make fine work on the Z-axis pretty iffy. I am wondering if anyone knows if a fine-feed unit can be obtained for this mill after the fact, or else, failing that, if there are any plans or write-ups online detailing the construction of one's own fine-feed system.

B) Does the CH-10M have the necessary rigidity and fineness of feed to do any boring work? If not then I would rather not waste any money on tooling for such.

C) Both of the depth readouts on the unit are pretty primitive (side scale with a pointer and that calibrated twist dial around the downfeed spindel (photo B). Any suggestions as to the best way to mount something like a dial gauge or such?

D) This unit has X-Y readouts that appear to be one single piece with the handwheel (photo D). This means you cannot roate them to zero them out, but instead have to do a lot of fussy number-math when doing any precision work. Can it be done and is it worth my time to try to refit the X-Y leadscrews with newer handwheels with the spring-loaded zero-able scales?

E) The spindle nose on this is short and the X table is made from (extruded?) aluminum (alloy?). That means that findng a place to lock down a magnetic DTI indicator base for tramming is not the easiest of tasks. Any suggestions as to the best DTI holders for this little beast?

Any advice or commentary welcome.

Looks like an X2 variant.....

Have a look here for parts.....http://www.arceurotrade.co.uk/machineparts/X2-Parts-Diagram-and-List-2012.pdf

You will need quite a few bits to make up the fine feed mechanism for the Z axis as per the diagrams, assuming the two machines are compatible.

You could use a digital readout scale for the Z axis instead of the rotary dial.....

In terms of rigidity, the column is hollow....many folk have filled the void with all manner of substances....Google..

Are you sure the X/Y axis dials are part of the hand wheel and not just stiff to rotate?

Edited By John Rudd on 18/11/2015 11:31:03

John, thanks for the info, especially that last bit about the X/Y axis dials. I took another look, loosened up the grub screws, gave 'em a shot of something on the lines of WD40 and then using a large pair of pliers (with some protective cushioning between jaws and verniers dials) gentley eased them free from whatever grease had frozen up inside. The dials now work quite well. One less problem to deal with. (audible sigh of relief!)

Good result there then?

As you say, one thing less to resolve..

If you just slid 1 or 2 T-nuts into the table slots and stood your mag holder on them would they give you enough pull to hold your magnetic dti holder down to the table?

Assuming your T-nuts are steel.

Edited By Robbo on 19/11/2015 19:18:44

Not an X2 but the same basic design with detail differences, notably the column on the X2 has thicker walls but isn't webbed and it doesn't have table stops, and the controls are in a box on the side of the head (instead of behind the swarf shield).

Looks in good condition, check the gears run smoothly. Greater benefit if seeking rigidity will benefit from a stiffening plate at the back of the column and attention to the fit between the bracket and the base, like all early X2 type machines.

You should be able to do an angular bearing upgrade, but check the sizes!

I have an X2 and rarely use the fine feed wheel, because I have a DRO and though you need care you can move the head to within a thou using the levers as they are so long.

You can fit a vertical DRO to the column on the right had side with a tab attaching the read head between the two gib screws visible in your picture: More flexible than using a dial gauge.

Edited By Neil Wyatt on 20/11/2015 07:56:16

Neil, much thanks for the feedback and I'll look into the idea of adding a stiffening plate. That digital readout might also be nice (Have to check my pocketbook on that one.)

This still begs the question as to whether or not this little mill is up to the task of using a (small) boring head. From what little I can find to read about these mills on the internet t seems they have a reputation for losing transmission gear teeth if subjected to overly-heavy cutting force. I'm thinking that unless one was very careful, feeding a boring head by means of the lever arms might accidently take too big a bite of the workpiece. What do you think?

It is easily done, breaking gears especially with interrupted cuts....fly cutter,boring head etc...

I made up my own belt drive for my mini mill,when the gears broke.....that said it is capable of cutting with a boring head, but a fine feed is needed or you may just stall the machine from too heavy a cut....

Edited By John Rudd on 20/11/2015 13:14:49

From what I have seen (and read) I can agree that a fine feed is required. It seems only natural that a motor-driven fine feed would produce the best results. Does fine-feeding with the little hand knob on the X2 work?

If this is sufficient it, of course, brings me around to trying to find some way to retrofit my machine with some (appropriate) gearing or mechanism to obtain the same result.

Given that I have only this vertical mill and a small Taig Micro lathe I am not completely certain that I can actually produce the required items to effect such a change. Or am I wrong?

Edited By John Rudd on 20/11/2015 17:35:07

John, thanks for the feedback. From what you say it looks like I'm going to have to solve the problem of equipping my mill with some sort of a fine feed before I think of throwing any good money at boring bars.

I have no problems boring holes much bigger than this one with my X2. I did one an inch diameter and over an inch deep in my toolpost in steel, and plenty of large diameter bearing pockets in aluminum. Just lock the slides and take it steady.