X2 conversion binding a little bit

[The Blight]

It should not bind at all.

How tight are your gibs? Can you actually move the table by pushing and pulling (not with your whole weight)? How have you connected the motors to the screws? You might want to check if the screws are missaligned.

What did you grind on the table? Just the curved underside?

[thegimpster]

The gibs go from tight to loose. I tighten them or loosen them from time to time to see if it helps any. So ya, I can move the table. The motors are connected to the screws with lovejoy couplers. It is possible that they could be off a little. I noticed that when i had the screw and the table off that the end that was turned down for the coupler seemed a little off from center.

I flipped the table over and ground underneath where the ballnut sits in the little cove. I ground the sharp corners (not the ones w/ the dovetails, but the ones just above the where the middle gets flat) off of the inside and smoothed the underneath off and made a little grove for the highest pont of the ball nut to sit into b/c it kind of hit the table. So i worked on the curve part of it basicaly.

[bilinghm]

You might consider lapping the ways. This removed the "tight spots" in the table movement and improved the smoothness on my X2. Also, you might want to check out:
http://www.cnczone.com/forums/showth...ghlight=plunge, there is a discussion of adjusting the bearing carrier and ballscrews to eliminate binding problems.

Bill

[The Blight]

I thought he did so already? Was the first thing I suggested here, and he said he had sanded down the high spots. You will also have to lap the gibs on a plane surface.

Sounds kind of odd.. How much power are you sending to the motors? How much power can your power supply deliver?

[thegimpster]

I sanded the dovetales and all. I will try the gibs tomorrow. One power supply is 24v @ 8a and the other is 0-50v @ upto 14a (its big too!)

[thegimpster]

bilinghm
I read your post. the thing at the end about using a depth micrometer seemed pretty interesting, but how could i do it on the x axis?

I'm still blowing black buggers from grinding all that crap today w/ the dremil.

maybe i am doing the lapping wrong? I simply sanded the dovetails and the flat surfaces w/ 600 grit then 2000 grit.

[bilinghm]

Adjusting the X requires a different strategy. Because of the way it is supported, it seemed to be easier to tune up without critical measurements. I didn't have binding in my X. However, the Y was difficult.

Lapping is somewhat different from sanding. The Industrial Hobbies site has a good description.

One problem that I discovered on my machine was poor contact between the gibb and the way. The gibb was canted and not making complete contact over its' full surface. I reground the little pockets where the adjustment screws fit, and fiddled until I achieved full contact. This helped a lot.

Bill

Originally Posted by thegimpster bilinghm I read your post. the thing at the end about using a depth micrometer seemed pretty interesting, but how could i do it on the x axis? I'm still blowing black buggers from grinding all that crap today w/ the dremil. maybe i am doing the lapping wrong? I simply sanded the dovetails and the flat surfaces w/ 600 grit then 2000 grit.

[thegimpster]

I sanded the crap out of the table today and the carriage the table mounts too. I started w/ 60 grit, then 120, then 600. It is a ton better. I spent prob 3 or 4 hours sanding. I still have the underside of the carriage to do and then the mill base. Hopefully that should help alot. I had to stop today and go on an interview on base. It took almost 2 1/2 hours. It went pretty good so hopefully I will get it.

[thegimpster]

after sanding all of the marks off of the table and base and carriage I got it back together and it is doing the same thing. It runs smooth for a few seconds then it jumps foreward a notch or too if that makes any sense. I have been trying to adjust it several ways, but still nothing. It does it a little on the Y axis but it is not too bad, the X on the other hand is pretty bad. Anyone out there got any ideas?

[ripples]

I exactly have same problem.. but my X2 has more binding at Y. This is what i did, I took the column out. Laid it on the flat surface (i used the floor). Using the head (took off all attachments) as the lapping medium, I "sandwiched" a 180 grit in between the the dovetails and ways and move the head back and forth with more pressure at the top end where i feel most of the bindings. I think using this way, I will be assured that the lapping will not create a "bow", or slightly depressed regions in the dovetails and ways... i felt some bit of bindings at X too usually at near ends. Using the table or the head as the lapping medium (adjusting the gibs little by little) is the way to go.. I will take some time and several changes of the used grit. It took me 3 hours last night, i noticed some significant reduction, almost smooth but not yet perfect (at least on gut feel). I ran out of 180 grit, i will finish this off using 600.

[skmetal7]

you can use some dykem die or a magic marker on the ways to see where the high spots are. where ever it rubs off, that's where you sand.