Gallery, Projects and General > How to's
Tramming an X2 without an indicator
superc:
A couple of weeks ago in accordance with my plans to upgrade the column mount on my MicroMark SX2 I also ordered a dial indicator at a too good to be true price off Ebay. It was indeed too good to be true. The clamps that came with it were the wrong size. I next obtained a fits all clamp from Sharf. LoL, it did fit the indicator, but not the rods I had. The vendor that sold me dial indicator has of course promised to replace all, but that was over a week ago and I am still waiting. Meanwhile the project to epoxy the SX2 column completed.
I have a digital inclinometer and with that I can tell if my column and the spindle is 90 degrees or not, and it implies my table is also, but I didn't trust just that device. Waiting for a mailman who may never come is frustrating.
Then I pondered it and I realized I still have a tilting column and the best indicator of a machine subtly out of tram is from examing the pattern produced by a fly cutter. I had some 1/4 inch hot rolled steel stock scrap.
My thought was why not see set it up as best as you can with the inclinometer then run a fly cutter over the steel stock and check the pattern that results? So I did. A terrible pattern. However this also gave me a chance to play some more with the modified mill. Different speeds, different feed rates, etc. It isn't like I had ever before successfully worked HR steel without problems before the column mod. If nothing else I confirmed the inclinometer at least put me into the ball park, even if the fly pattern showed I was out of tram.
Tonight I hit upon a redneck solution involving a ballpeen hammer instead of the usual plastic mallet and multiple passes with the flycutter.
I ever so slightly loosened the column nut and ran the flycutter into the center of the piece, then gave the top of the side of the column that was cutting the most a tap with the ballpeen hammer then finished the pass and examined the finish. This went on for awhile, left side, then right, etc. The passes were shallow because the only goal was to create a flycutter pattern to examine.
After about 10 gentle but firm taps and passes I found a sweet spot that produced cutting on both sides of the single blade flycutter.
I then locked the column down tight and did an entire pass with that column setting.
A perfect flycutter pattern. I believe my machine is now properly trammed on X axis. Tomorrow I will spin the vise around with the other side of the plate and see what happens on my Y axis. I will also make a cold chisel mark on the column and base so I can always quickly land near the sweet spot again if I have to move the column. The finish of the experimental piece is probably about as close to mirror as a mill can make it.
Stilldrillin:
Hi C.
Nicely done! :clap: :clap:
Back in the days when I had to work for a living, on grown up machines.
I trammed, using a horizontal, 12" long piece of bar, held in the machine's spindle. And a steel block/ feeler, sliding between table and bar.
Taking two equal feelings, 180dgrs apart, (ie. over 24"), gave the perfect tram....... :thumbup:
David D
superc:
It has been said, with a big enough hammer, or enough dynamite, any problem can be solved. :)
Thank you. I was worried 'hit it with a hammer' may not be socially acceptable as an X2 fix, but I also thought it was important to get the word out that sometimes that does indeed work well. Secret is just firm taps from a big enough hammer. If I had not filled the core with an epoxy/steel/sand mix I would have been more reluctant, fearing denting or buckling or cracking of the column, but it all came out pretty solid, so I didn't think that would hurt it any more than beating on an old Buick flathead engine would hurt that. I was right.
For those wondering, since hardly anyone just sells pre-cut 3/8 inch HSS fly cutter bits and all of my efforts to grind one of my own have failed, I used a store (Micro Mark) #4980L 8mm lathe bit. Left hand bit tightened down upside down into the fly cutter. It was loose of course. So I tightened a single edge razor blade edge down into a workbench vise, then snapped the back off with a big hammer. Snapped clean. I took that piece of steel back and it fit perfectly alongside the lathe bit in the fly cutter. :)
Hmm, it probably isn't the approved fly cutter shape, but I can report (as the photos show) the cheap 4980L mini lathe bits work perfectly in the Micromark fly cutter on hot rolled steel. I may buy some more of them.
I have a tachometer for the mini lathe. Hooked it up to the SX2, took readings, and then marked them on the rheostat box. No need for a tach now 'cause that effectively gave me a speedometer.
I know, I was supposed to run it at about 430 RPM and 8 feet minute feed. That worked, but in the real world so too did 6-800 RPM and about 5 feet a minute hand cranked. Just slow and steady.
So will an SX2 with an epoxied column cut steel plate? Oh heck yes.
Biggest problem I am encountering with the SX2 now is the small size of the work aperture. That steel plate is about 6" by 2.75" and in order to fly cut it I had to take the big Sharf vise out of center position, insert the fly cutter (only 7" of Z room), then put the vise back. Of course that business with moving the vise first wouldn't be needed on a full size machine. Likewise I needed 3" on either end of the 6" steel plate for the fly cutter to fully exit the workpiece. Unfortunately my SX2's bed travel is only 11" along the X axis. One end suffered and did not experience the full fly cutter effect. Likewise, although I was kicking around the idea of flycutting the piece along the Y axis to check that tram, since the bed travel is only 4 inches and I should have 3 inches on either side for the fly cutter to exit, I realize now that test can not be run on this machine as I will not have even one side clear enough for the flycutter to exit along the Y axis. Even doing it sideways and with only one side fully exiting, I would need at least 6" of Y travel (probably more if you take the vise footprint into account). Durn shame. T'would have been a good easy test of Y axis Tram.
I have a faint suspicion that my mill head leans inward just a hair. If you look at the plate you see the flycutting looks fainter along one long axis. That was the side near the column. I have read many webpages where folks found Y axis issues with their X2 heads. Aluminum foil fixes and all that. I had the head off yesterday morning while I was playing with the quill gear (shaft was very grungy and the fine adjustment had been sticking and no, it isn't necessary to remove the column to detach the head or remove the quill handle/gear) so I see where the shim would go, but sheesh, couldn't they have done that at the factory? If they didn't want to put it together right (or polish out the tool marks on the gibs) why didn't they just drop the price a little and send us a box of loose parts as a kit (as Jinma did for my 8" wood chipper a few years ago, a 5' 3/4 ton crate of metal parts with instructions for assembly written in Chinese)? Yeah okay, maybe a head shim is in my future too. Don't know yet. For 99% of anything I anticipate doing here the fact that the mill head is possibly the thickness of a cat fur off in angle at the bed really won't matter worth a durn. Trust me, the lawn mower won't care. :)
But anyway, the X2 work aperture is small, but I have no room (or funding, or electricity for a real machine (LoL let's crush the basement floor with a real machine, NOT). Still for well less than a $1G it is a durn nice accessory for any work at home mechanic type. There is just so much to learn with it.
MetalMuncher:
Just wanted to say that the Y axis on mine was off a bit as well. I remember I put a shim in at the base of the column. I don't remember how thick it was (I used a feeler gauge).
To tram mine I clamp a piece of precision ground steel plate 4" wide x 7" long to the table, and then use a Baker back-plunger indicator in a collet, so I can swing the full circle without having to jump the T slots with the indicator. As I recall, the Y axis was off a few mils, and once I added the shim to raise the front of the head I got it down to about 1.2 mil difference front to back, and decided to accept that, as trying other thicknesses didn't seem to get any closer to plumb.
But well done on your indicator-less method! One thing that makes me notice I need to check the tram is when my R8 flycutter starts cutting more in one direction than the other, along the X axis. It seems to me like the big nut they have to hold the column in tram on this model of mill is not the best solution, so I made a large turnbuckle and added it to the left side of the column (facing it) so that when I crank down the big retaining nut the column can't move. I used what amount to miniature tie rod ends, welded to steel tube, with a nut welded in the middle for a wrench to turn it. I take the end play out just like you would with a lead screw, by always starting out of tram a bit to the left. Then by turning the turnbuckle to extend it, I bring the tram into center with the indicator by moving the column clockwise. I got tired of seeing a variance in tram every time I tightened that nut. ;)
Stilldrillin:
I used a bit of drinks can alloy, to shim in Y.
Later, replaced my spring saucer, with a 5/8" thick washer..... http://madmodder.net/index.php/topic,7643.msg81954.html#msg81954
The column didn't move, as I trammed and tightened.
Also, it hasn't moved out of tram over the past two years. Fit n forget! :thumbup:
David D
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