X2 Mill Overhaul - Advice welcome

[CrewCab]

Right Gang 8)

I've had my little X2 Mill for about 3 months now and found it to be a very capable little feller, it's had a belt drive conversion and an air spring added, both of which have been imho well worth doing.

Having used it a fair bit, OK mainly playing just to get used to it I've now taken the plunge and spent far tooooo much on a DRO ??? ........... Having decided that was the way I wanted to go I had a good look around and eventually followed Mr BogStandard's recommendation and ordered one from these guys (I'm in the UK) Click Here ............ thanks John. After a few emails and telephone conversations I placed an order on Thursday and it arrived today (Friday), from my dealings with these guys so far I am very pleased and the kit (still in the box) certainly looks the part.

Anyway ............. waffle over (for now)

Fitting the DRO seems straightforward, mebbee a couple of bracket to make etc ....


but, .... I thought I would take the opportunity and strip the Mill, give it a good clean out of the Chinese grease etc and see if owt' needs any attention .......... that's where you guys come in I hope.


1) After fitting the Belt Drive I filed the instructions .......... obviously they are very safe as I can't find them for love nor' money ............ does anyone have a copy they can scan and email, I would like to take out the redundant gears whilst it's in bits, just pm me for my email address please.

2) Any suggestions for fine tuning, I can lap and polish the gib strips and mating surfaces etc to a degree, but they are far better than I had imagined to be fair.

2) Most of the play in the feed / leadscrews seems to be due to the slop in the large "phosphor bronze" (I think) nuts, which seem to have been fitted by using the technique of "Large Hammer" plus "Round Peg and Square Hole", then again it works :

enough from me for now, any advice welcome (sensible or otherwise) :big:

CC

 

[CrewCab]

And a second Question :

Has anyone come up with a better / alternative method of stopping the chips falling on the Y axis leadscrew instead of the concertina plastic do dad's, they are terrible to clean the chips off and I just don't think they will have along life span ???

CC

 

[ksouers]

Dave,
Congratulations on the DRO, I just fitted one recently and it's been worth every penny! I've thought about doing the belt-drive mod, but I'm also considering upgrading to an X3, not sure yet which way I'm going to go.

I've had my X2 for about 4 years now, a couple things that helped mine: I went over every dovetail with 800 and 1200 grit silicon carbide as best I could. Then I used Mother's California Polish and repeatedly lapped the dovetails. Mother's is a fine polish for brightening aluminum wheels, I'm sure you can find something similar in the UK. It worked great on the cast iron. Just make sure you polish the entire dovetail and clean up after it very well. I didn't go over it so hard that I removed all the tool marks, just enough to break the rough edges and smooth things up a bit.

I also broke every burr edge I could find with either a file or silicon carbide. I took everything apart that I could and cleaned out as much of the casting sand as I could find. It seems some of it had gotten stuck in the paint and I was finding it for weeks.

I had to shim out the block for the fine downfeed a couple thou with some aluminum foil, that made a huge difference!

One problem I've come across is the dovetail faces are not quite parallel so the table or powerhead will bind at one extreme or the other. Other than completely reworking the doves, the solution I've come up with is to try to use the the table where it binds the most so that gets the most wear on it. It's not great, but it works.

I've also had the thrust bearings on X work loose, pressing them back into place has reduced a lot of the backlash on that axis.

Getting the head trammed left-to-right is easy. Getting trammed front-to-back is a pain. I've slipped shims in the big circle to try to get it right, but it hasn't always worked out well for me. If anyone has any suggestions for this I'd be glad to try it!

The big thing is just get everything adjusted right. It's often hard to do, sometimes it's an invisible line between too much and not enough. As far as I can tell it'll never be perfect, but it can be tolerable.

Keep us posted! I'm real interested in how it turns out!

 

[ksouers]

And a second Question :

Has anyone come up with a better / alternative method of stopping the chips falling on the Y axis leadscrew instead of the concertina plastic do dad's, they are terrible to clean the chips off and I just don't think they will have along life span ???

CC

No, I haven't. Not yet. Mine are splitting at the folds. And now I have to cover my DRO as well.

 

[rake60]

The X2 is a very capable little machine for it's price.

It isn't a hyper sensitive, super accurate machine no matter how much
money you throw at it.

You CAN still get hyper sensitive, super accurate results from it!
That comes from experience in working with the machine.
It will teach you it's strengths and weaknesses.

From there it's "Operator Finesse" to get the right answer to what you
are asking the machine to do.

I've run million dollar industrial machines that had been pressed past their
limits for far too many years. They were considered JUNK by many of the other
operators. I had no problem holding a .0005 tolerance on a bearing fit with them.

You'll never tell a machine what it's going to do.

It will tell you what it will do and you need to accept that and work within
it's parameters.

Rick

 

[CrewCab]

The X2 is a very capable little machine for it's price.

Too true Rick, and that's just from my limited experience, I could have bought a bigger Mill but the X2 fits the bill for me, all I'm trying to do is a little fine tuning, getting rid (hopefully) of the little bit of binding here and there and just making it a little sweeter. I love the little feller, it will be far more capable than me I'm sure, but all I'm after is a little "honing" whilst I've got the chance. After about an hour polishing and adjusting the "Y" travel I can feel a little improvement (and I mean "LITTLE") but that's good ............... anyway.......... it keeps me off the streets .......... for some obscure reason I find sanding / polishing therapeutic ......... sad I know ............... do I need therapy

Cheers

Dave

 

[Brass_Machine]

.......... for some obscure reason I find sanding / polishing therapeutic ......... sad I know ............... do I need therapy

Cheers

Dave

Dave... you do need therapy. In your case more sanding and polishing. My X2 is waiting.... :big:

Eric

 

[Hilmar]

I think he wants the instruction for the belt mod. If so how can I send him these as attachments via E-Mail????
Hilmar

PS I have the drive from littlemachineshop.com/

 

[CrewCab]

Hilmar, PM sent.

many thanks

Dave

 

[Hilmar]

Dave check Your E_Mail and let me know how it comes out
Hilmar

 

[CrewCab]

Email received Hilmar, all the pages came through just fine ............ Thanks 8)

Dave

 

[ksouers]

Dave,
Some more thoughts on how I tuned up my X2.
I agree the X2 is a very capable machine and I enjoy using it, but it is definitely not ready to run right out of the box. It needs some clean up and adjustment before it is ready to go to work.

The first thing I did (well, after a couple days playing with it) was completely tear it down to basic components. It was a lot easier to work with the individual parts.

For sanding the doves I wrapped some silicon carbide paper around the gibs and pressed that into the doves and moved it along the entire face with just fingertip pressure. I did that for the angled and flat parts. I noticed the angled face was wavy over it’s length, I think that contributed to some of the binding and difficulty in adjusting the gibs. The sanding didn’t remove it but smoothed it out somewhat so there was more flat area to contact with.

When polishing, I mated the two pieces together with a couple dabs of polish then lightly snugged up on the gibs, just enough so I could slide the pieces by hand with some resistance. I worked the pieces their full length. The previous sanding left much of the factory tool marks untouched. As these were broken down by the polishing the gibs would need frequent adjusting to maintain pressure. After about a dozen strokes the old polish was cleaned up with some paper towels and fresh polish applied. The whole thing was repeated until movement was smooth(er) along the entire length of travel with a little extra concentration on the stiffer areas. The whole thing was then cleaned up very well with kerosene (paraffin) and WD40. The final result was that most of the tooling marks were still intact but sharp edges were broken down and contact area was increased by about 200% - 300% (there wasn’t really much to start with). Tool marks were completely removed on the highest spots, but there were still plenty of pockets to hold oil.

Early on I tried several different oils to lubricate the ways. I finally settled on Mobil 1 synthetic oil. That really removed a lot of friction in the systems.

Adjusting the gibs can seem like banging your head against a wall. Everything will be too loose and wobbly, then you make that final little tweak and everything is bound up tight. I’m afraid I can’t help you much there. You’ll just have to keep messing with it till it works out right. I’ll loosen up all the grub screws then working with the inside ones adjust only one at a time. When one is right I move on to the next, working my way out. And hoping I don’t mess it up and have to start over again.

The bronze nuts. I’ve noticed that they work best when slightly loose, as the lead screws tend to wobble a bit. The grub screws should just touch the nuts and lightly hold them in place, you should be able to see the nut wobble as you turn the leadscrews. The DRO is your best friend here when dealing with backlash.

The fine downfeed has lots of problems. There is very little that can be done to adjust it and there is lots of play built into the system. Starting at the rack the teeth aren’t meshed properly. Shimming out the rack may help a little. The worm gear is just terrible. I haven’t been able to do anything with it yet. The dog clutch easily has .010 slop in it. The wobbly universal joint thingy shaft is just pinned together and looks more like an afterthought to help line up the worm gear and downfeed wheel. Mine was binding and I couldn’t figure out what it was. I tried a thin copper washer behind the handwheel to take out some of the back lash. It helped a little. Then I tried shimming out the block the handwheel rides in. That helped out tremendously! It didn’t clean up the backlash but it did make it operate much easier with far less effort. The binding is now gone. I can now easily feed .001, .0005 if I’m careful. Before it would bind up so bad that I couldn’t get it to move, then suddenly it would break loose and jump .005 or .010 or worse.

None of this really makes the machine more accurate, but it does make it easier and smoother to use and allows a closer adjustment on the gibs, improving repeatability. There is less error and “noise” that will be transferred to the work piece. Essentially you are just hastening the break-in period. Over time the machine will get worn in and become even better, but that takes time and usage. As Rick said, the single best addition that can be made to any machine is the installation of an experienced operator. The more you use the machine the better it will become, more importantly the better you will become at knowing your machine.

 

[CrewCab]

Thanks Kevin,
The Y axis is the one which was binding the most, mainly at each end; after a couple of hours today doing some light sanding / lapping then adjusting the brass nut and hand wheel mount I've got it down to just being a bit tight for the last 5mm of travel in each direction, I can live with that. The X axis was always better so I've just tried to take the obvious rough edges off, I'll see if there is any noticeable difference once it all goes back together.

As for the Z, to be fair it seems fine so I wasn't going to do much, although if I'm taking the redundant gears out the head needs to come off I'll have a look then (Thanks to Hilmar for the copy of the instructions).

Dave

 

[CrewCab]

Fitting the DRO seems straightforward

If I use the phrase "It seems straightforward" ever again please feel free to SHOUT at me : :wall:

CC

??? :

 

[ksouers]

RUH ROH

What happened?

 

[CrewCab]

Nothing serious ??? after an hour or so of making brackets to mount the Y axis scale I fitted it in place, then realised I hadn't left enough clearance for the X feed leadscrew :wall:

Oh well, back to the drawing board

Dave

 

[tmuir]

Once you have it all sorted do post pictures as that would be most helpful for me as I have an X2 still sitting on my bench with it's packing grease on it so I have still all the tweaks and improvements to do yet.

Thanks
Tony

 

[CrewCab]

No problem with pictures Tony, but I may be a while ;D

CC

 

[Hilmar]

Nothing serious Huh? after an hour or so of making brackets to mount the Y axis scale I fitted it in place, then realised I hadn't left enough clearance for the X feed leadscrew wall bash

Dave, go to Tool& Tips,
go to Tools
go to page 13
go to 5th from bottom under DRO look for my Pics on first page to the end.
If you need help let me know
Hilmar

 

[CrewCab]

Cheers Hilmar ;D

Hopefully I'm on the right track now, just going to pt the mill back together and make some brackets, though summer seems to have eventually arrived here today in the UK, really we out to break out the BBQ as we may not get many more sunny days this year :

Dave