setting up x2

[shvanbc]

Hi all,

I got my X2 from HF and am trying to set it up. I have two questions:

Moving the table along the X axis seems to be relatively smooth except when the table is all the way to the left. At that end, it is so sticky that I almost need two hands to move it. Is this something that will be helped with Crevice Reamer's way smoothing guide? Is there anything simpler that I can do before taking the whole thing apart? I've played around with the gib but that doesn't seem to help at all with the stickiness.

Second, my Y-axis handle doesn't slide on all the way. The key that mates with the slot on the handle has a raised "bump" on the end of it closest to the table. I cannot push the handle past it. Is this bump supposed to be there? I took of the x-axis handle and didn't see any bump on the key there. I think that as a result of this, I have to turn the handle on the Y-Axis almost two full revolutions when reversing direction before the table will start moving. During those two full revolutions the lead screw and handle itself is coming in or out of the table but the table is not moving. You can see the gap between the handle and the table opening and closing as this is happening.

Thanks for any help. Sorry if this isn't very well described or I made any mistakes in terminology - I'm brand new to this!

[TroyO]

That bump sounds like a defect... I'd file it down if it were me. Maybe it got smacked around a little?

The table movement.... You should at least try flattening the gib out by sanding it on a flat surface with a sheet of wet/dry paper glued to it.

Before you go to way smoothing though... try taking out the Gib, marking all over the gib and the dovetails and ways with a magic marker (Blue works well.. anything will do though.)

Leave it a touch loose and run it back and forth a few times and let it get jammed, then look to see where the magic marker has rubbed off. That is what is probably causing the jamming. One thing to look at... see if only the top of your gib is contacting the dovetail. If it is, you may have to re-drill the pips on the gib. That way, if you go to the way smoothing you will know what areas need the most attention.

I think mine when I got it was about a worst case scenario... I had to work it a lot to get it smooth all the way, including some touch up with files and by "hand scrapping" which actually isn't near as hard as it sounds. (At least... at the kind of half arsed level needed to get things working on a small machine like this...) Anyway... I salvaged it, and see no reason it won't be a long lasting, accurate little machine now that I finally got it going.

Frst step is some basics... and finding out where the problem is. The full tear down isn't that hard, especially with CreviceReamers nice step by step guide! (Thanks CreviceReamer!)

[shvanbc]

thanks for the suggestions - I'll try smoothing the x gib first

so... is it possible to remove and re-install the gib without disassembling the table?

thanks

[TroyO]

Yes, just back off the gib locking screws far enough and you can pop the gib out.

[TroyO]

Another thought... when the table is all the way left would mean it was screwed all the way "in". That could be something else, come to think of it.

There's some play in the way that end cap (I think it's a "X axis bearing support" by the parts list...) bolts on to the table. Wind the table all the way over to where it sticks, then try loosening the cap screws that hold that plate on and see if it frees up. If it does, wind it all the way over and then re-tigten those screws. That will line up the leadscrew with the leadscrew nut. You could be binding up there too.

Haha, edit because I realized there's another similar adjustment that could be that far out on a new mill... LOL.

Just under the handwheel on the saddle are two set screws... they hold in the leadscrew nut. You can loosen those and run the table to left then tighten them back up. Same idea... getting the leadscrew and leadscrew nut all centered with each other.

[shvanbc]

Another thought... when the table is all the way left would mean it was screwed all the way "in". That could be something else, come to think of it.

There's some play in the way that end cap (I think it's a "X axis bearing support" by the parts list...) bolts on to the table. Wind the table all the way over to where it sticks, then try loosening the cap screws that hold that plate on and see if it frees up. If it does, wind it all the way over and then re-tigten those screws. That will line up the leadscrew with the leadscrew nut. You could be binding up there too.

Brilliant! I did as you suggested and the X-axis travel is now uniformly smooth from end to end.

I tried to do the same with the Y-axis and I think it helped a bit but it still gets a little sticky when the table is close to the column. I think I may have to live with it for now.

Now to try a first cut...

Thanks so much!

Steve

[TroyO]

Glad it helped.

If it's towards the column that it's sticky, but not to the front then it's probably a gib/ways problem at the back of the travel.

Mine was just a touch like that even after lapping, and I found that just winding it through that stiff section of travel several dozens of times was enough to "wear it in". (Probably like 75 cycles.)

Give it a cleanup when you are done... that "wearing in" will make some grey oil full of metal particles... you want to wear in, not wear out, LOL.

[shvanbc]

thanks TroyO, I'll try wearing the Y in a little more.

I've been using the mill on a block of aluminum just to get a feel for it. The results haven't been too bad but it's definitely isn't perfectly square. I also get ridges that I can feel between passes of the end mill. I think this means I need to align the spindle to the column?

Another thing - when I move the X-Axis while milling it will groan/grind really loudly at certain points in the x travel. I figure I need to oil the x-axis ways and lead screw better but don't really know how to do it without just blindly squirting oil up under the table and hoping it lands somewhere useful. Is there a better technique?

Steve

[TroyO]

Read up on "Tramming" and it will get you going in the right direction... there are a lot of ways to do it.

If you don't have a DTI (Dial Test indicator... measures to .0001 inch or thereabouts, depending on model.) a somewhat less exact but dirt cheap method is to bend a piece of stout rod (1/4 steel round from Home Depot is good.) so it is kind of shaped like this:

 U    <----Spindle
 |
 |
 |______  <Bent Rod
         |
         |
         |

__________________________________
                     Table         |

If you spin that to one side of the table and get it to where you can just slip a piece of paper under it so it gently touches, then to the other side and you can get the same slip fit on the paper then everything is square. Otherwise you need to keep tweaking the column left/right until it's as close as you can get.

That's probably why you get the ridges... it could be other things but you need that dead square.

LOL, kind of funny... you are a step ahead of me at the moment... I have been tweaking/improving/smoothing/cleaning mine for weeks... haven't actually used it yet, LOL.

The groaning sounds indicate the setup isn't rigid enough... something is shaking about. Check gibs, nut on back of column, etc or take lighter passes. How deep are you going, with what size end mill? How is the work clamped?

[shvanbc]

I did tram the mill already with the method you described. At the time it was to within 0.001" but I should check again.

The ridges I get are "between" each pass of the end mill, i.e., I mill along the x-axis (y and z axis are locked in position) and then move the y position up about 2/3 of the diameter of the end mill and then go again along the x-axis until the whole block is done. The ridges run along the x-axis where the edge of the end mill passed.

I was using a 3/4" 4-flute end-mill. DOC was around 0.02-0.03" I think. I clamped it in a vise.

I should probably have spent more time setting it up but I was impatient to actually mill something

[TroyO]

You can use the same method described above to check it front to back too.... adjusting it isn't that easy, though.

I *think*, if I recall that you can use aluminium as shims between the column mount and the base... that back circular casting that bolts on to the table with 3 huge socket head screws.

See which way it's off, and try shimming between those 2 parts to get it closer.

[photomankc]

Y tram is tricky you can just shim the column but then you may end up knocking it out of square with the table which will cause your X/Y position to drift around as you raise and lower the head. The real way to do this is to first get the spindle truly parallel with the column. The process is detailed here:
http://www.homemodelenginemachinist....p?topic=6007.0

Prepare for a job that is not really fun. At all. You are trying to shift the housing left or right on the head carriage to correct the X and shim it at the top or bottom to correct any nodding forwards or backwards on the Y. Once you get the Z-X/Z-Y as parallel to the Z ways as possible then you can shim the column to get it perpendicular to the tables. I used foil between the column and the circular base mount to tilt it slightly backwards. That will give you good tram and steady X/Y position over the full movement of Z. If you don't do that then you have to choose one or the other.

Now I can run a 2.5" facemill over two passes along the X axis and there will be maybe a 0.0005" step between the passes. Before I could snag a fingernail on the step left by passes with a 1/2" endmill.