Is it possible that the X axis ways are not accurately ground?

[phantomcow2]

I have an X1 micro mill, I am very happy with it except for one thing.
That is, about half way throught he X axis travel, when the table is moving toward the left, it becomes slightly more difficult to turn. Then as you keep going it becomes hard enough you need 2 hands to do it comfortably. And when you near the end, its so hard that you need two hands and i am shaking the entire table.
I was told it was the leadscrew binding, i realigned the nut and bearing block. Still nothing.
So i did a little experiment, i removed the leadscrew all together and tried to see if i could just slide the table by hand. Nope, all was smooth until i felt more and more resistance until with all my might i could not push the table any further.
The only thing i can think of is that my table is not ground entirely flat, its at a slight angle. Is there anything i can do about this?
At school they have a surface grinder, i have never used these before and have no idea what they are used for, would that help?

[rustyolddo]

Oh yeah. It's possible & probable. Problem is you have to figure out where the problem is. Might not be easy to fix with just a surface grinder especially if it's in the dovetail. You can use Dykem to find where the tight spots are and proceed from there.

[phantomcow2]

what do you mean use dykem to find out where the tight spots are?
Like apply the dykem to the contact areas and see where it scraps it off?
We have a full sized bridgeport mill with dovetail cutters at school, is "refacing" the dovetails a possible solution?
I like that dykem idea, i use that stuff a lot at school but i should pick up a bottle myself.
Thanks for the reply,

[mxtras]

Prussian blue, not Dykem.

Scott

[JFettig]

I think all you really have to do is loosen the leadscrew mount, move it around and find a good spot where it moves well, same with the leadnut mount. That is typically the problem when it happens to me.

Jon

[Bloy2004]

Check the inside "VEE" of the dovetails... I had a similar problem with a mini lathe and found that the point of the outer dovetail was rubbing on the inside of the mating dovetail. I had to groove it out more and also filed off the shart edge of the outer dovetail. Once the surfaces of the dovetails were allowed to mate, the sliding action was smooth from end to end of travel. It took me a while to find that the groove of the inside dovetail was machined without adequate clearance.

[phantomcow2]

Originally Posted by JFettig I think all you really have to do is loosen the leadscrew mount, move it around and find a good spot where it moves well, same with the leadnut mount. That is typically the problem when it happens to me. Jon

I thought it was, and i have done that many times. But the fact that i encountered the same problem WITHOUT the leadscrew all together, leads me to believe otherwise.

[phantomcow2]

Originally Posted by Bloy2004 Check the inside "VEE" of the dovetails... I had a similar problem with a mini lathe and found that the point of the outer dovetail was rubbing on the inside of the mating dovetail. I had to groove it out more and also filed off the shart edge of the outer dovetail. Once the surfaces of the dovetails were allowed to mate, the sliding action was smooth from end to end of travel. It took me a while to find that the groove of the inside dovetail was machined without adequate clearance.

I think i get it, so at the factory the dovetail cutters did not move in deep enough for part of the travel, causing the binding. Or perhaps the table was not square with the cutter, this seems likely because the gibs are extremely tight near the end of the travel. But slightly loose toward the start

[pacosoide]

I agree with the previous observation. I would loosen the gibs and see if you still have the same problem. Most of the time is the gibs too tight on one side.
Jose.

[phantomcow2]

Originally Posted by pacosoide I agree with the previous observation. I would loosen the gibs and see if you still have the same problem. Most of the time is the gibs too tight on one side. Jose.

If i loosen the gibs, it works alright. BUt here is what leads to suspect an innacuracy
On the part where it starts to be harder to turn (about half way through its travel), the gibs tighten up, then if i keep it going to the max where its the hardest to turn, adjust the gibs like i normally would, there is play when it comes to the other end of the travel. Clearly an angle exists which should not
I sanded down what i could, but i want to see if I can use hte surface grinder and dovetail cutter at school.
I really dont want to buy another table because in November the long table for the micro comes out and i will just buy that.

[phantomcow2]

ANd assuming the dovetails and all are not accurately ground, and i cant do it at school for liability ot whatever, what would I be looking at for having a machine shop do this?
I can get a dovetail cutter no problem, its another mill i have a problem with. A friend of mine is deciding on which mill to buy, maybe i can hurry him up and use that

[motomitch1]

Sounds like your dovetails are not parallel.If You can get two .375 dia. dowel pins and set them down inside the dovetails you can mic over them.Do that on both ends and the middle.you can see how bad it is.