[uberlinuxgeek]

Hello,
Tramming procedure, after working with jt this past week on an issue I was having with tram and what I thought was a sag issue on the 5th column end. I had installed a dro and pressurized strut to help keep tram when moving the bridge. Now I don't need it. I had tramed the front to back with a shim under the lift plate before but didn't think about the other till now. So I hope this will help someone.
Place an indacol or and dial indicator on swing arm mounted on the quill or in a collet. Lower the Bridge so that the indicator is 0.100 down in a spot and leave the 5th and lift lock unlocked and Center the table under the quill and allow the swing of the indicator to reach the edge of the table across the x axis because the further out you go the more accurate the tram. But during all of the measurements make sure you are 180 degrees from each point on each axis to give the best acuracy. The goal is so that the measurment is the same at all points, within .0005 or less is the best. You may wish to start with the y axis first and once you have that it may be just a matter of moving the shims along the x axis under the lift plate. To be able to get the shims under the lift plate you lock the 5th end, loosen the 4 bolts securing the lift plate to the headstock and if you need to place them front by the chuck you drop the Bridge and it causes the plate to lift by the chuck, if you need to get shims by the pully end you raise the bridge, by locking just the 5th end moving the Bridge causes a leverage action lifting the lift plate. Position of shims by the chuck end causes the Bridge to raise on the 5th end. So for me I got tram on the y axis 1st and moved the shims to help raise the 5th end till I got close and if needed added the same shim size to both sides to help get the x axis in tram. For me I added .022 on the motor side at the very front by chuck and .003 on the operator side back by the mounting bolt towards the chuck. Moving the shim of even the same size along the x axis under the lift plate can have a large effect on the tram in the x axis. When done it took about 3 hrs to get within .0005 on all axis. Please note tram needs to be done with the bridge unlocked on both sides so when you use the a axis for machining it stays in tram. If you are going to lock the Bridge to just use the quill to keep tram you first lock the lift end and then the 5th end. Make sure the 5th column is squared to the Bridge so when you lock it it doesn't effect the tram.
JT helped me with some of this info and asked me to pass my experience along

[countryguy]

Awesome! and thanks for writing this up! We need to all stick together. Hey, what's the "lift plate" and then I'll take to this w/ a few other mill maintenance items soon.
Honestly I have never trammed this and know the procedure but no time/cycles is my deal it seems. Challenge- I dare ya to do a Vid for You tube. IF you do that, I'll own up to a ball-screw replacement/ upsize vid! LOL. Or a brace vid. What ever ya'll desire.

[uberlinuxgeek]

I'll have to think on the vid, not comfortable with speaking. Not knowing for sure the part term, I called the plate that the 4 columns are on that lift the bridge, this is the part directly on top of the lathe headstock that the columns are attached to. There are 4 bolts that secure it to the headstock and 1 center bolt you use to add oil to the headstock. My tram was out so bad along x that I had a 90lb strut to help keep where needed and a 2nd dro to match up each side, now don't need it.

[uberlinuxgeek]

And yes sticking together is a good call, I think if more people could share their experiences it would be a good thing. Chinese machines always need work before they are 100 percent. All of mine have, even from some of the better sources. Heck even my us made machines needed tweaking to be their best. Shopmaster stands behind their machines from all My experiences so far. Are there bad ones sure but jt has worked with me on a bad big part already. These are hobby and light buisness machines, I can hold +-.002 with no issue and for a hobby tool that is just fine, that is what others have shared as well, but if more could express their experiences people would have a fair expectation, they are not top of the line, and after managing setups with a bit of time I can hold .0005 but you need to know what you are doing and if this is your first machine you will have growing pains because you need to know how to adjust things and you won't have the experience to know all of that. Asking non hostile questions from forum people is the best way to advance and reading all you can will help. Just my experience

[uberlinuxgeek]

Locations of shims, used feeler gauges .

[countryguy]

OK, Time to ask for help & suggestions. Thanks for the pics UberLG
Now I get it based on the pics. I've been off doing springtime stuff here on the Farm. Now, I have a Q on this as I try to make something. Is this tram shim work on the lift for the Mill head in the X direction only? I have been experimenting with milling 6" aluminum blocks into Squares.... To try and see how close I can get. Cutting in Y direct. (bar running Y+ to Y-) in the vise. 1"x 1" x 6" I am seemingly off .2mm or .0156 I assume I'll need to pull the saddle out and do something? Shim it down in the base. Once Y is done, then I do use ULG's process noted here and make long bars in X and tram the column head end?

Thanks for the help.

[uberlinuxgeek]

Hello,
Actually this does both x and y. It takes a lot of time but based on where you place the shims under the column lower plate and how thick they are front to back will influence the y axis. It took me about 4 solid hours to play with this to get both x and y in tram.

[countryguy]

OK, To keep the tread alive- I see that the top bridge plate and spindle is independent of the Saddle system then. So to tram the head really means you are making it true to the saddles position. I do have shims under the saddle. I remember them when I did the ball screw precision bearing upgrade. That saddle sits on the X ways and glides along under the fixed spindle head. Ok, so, I think I will get the Bridge loosened and re-read your doc. I guess I'm not sure of where to shim the bridge plate if the table is cutting low on one side of Y. Anyway. I need to make something and I'll play w/ this a bit over the next few days. The Misses is gone so I get to really play all day in the shop till Sunday. Enjoy!
Cg.

[uberlinuxgeek]

When I tramed I used a homemade indicol like used on Bridgeport and but placed in the spindle and swiveled it along x and y so that the spindle was square to the table like on my smaller mill. But left the bridge unlocked. Then once done that way as would be during milling operation the I rechecked with the bridge locked on the lift end and then the 5th end. Also double checked when locking the spindle. With the 5th end squared and supported I had no significant change in tram. This was all done after the x and y gibs are adjusted for normal operation. Hope that helps

[uberlinuxgeek]

Cg, I guess i will look into about low cutting on mine. I am not sure after an accurate tram that may be happening.
Thanks

[uberlinuxgeek]

It is always fun to play when the wife is gone. Not sure doing alignments is that much fun, but hey I am busy right now with installing home switches, and since there are no provisions for it, take a bit of time to do the mounts. For shimming for low Y, I would add shims to the low side to raise up, but the bugger is that you end up influencing the X in the process and end up going back to checking that to. What can help is that by placing the shim towards the center of the bridge lift plate and not on one side or the other may help X not get so bad off. I ended up going back and forth a lot with this. Good luck CG if I can help let me know.

[walters474]

As my El Dorado came, it saged by the fifth column. I've always only trammed the mill bridge when changing the height of the mill bridge by stacking parallels on the 4 column base plate and sandwich tightly against the bottom of the lift plate. Shims (or feeler gauges) are used to tram. Shim the center of approperate parallel stack for Y axis and shim edge of other stack for X axis (easily takes care of the sag). Just add or take away parallels when bridge height change is needed. Makes the mill bridge much stiffer as well.