[WOTDesigns]

I finished 2 good sized production runs on new 1100 and have no jobs pending so I finally have time to tackle the blocked oil path in the head.

My 1100 arrived with a clog on the right side of the head. Plenty of pressure in the line to the Banjo but nothing getting through. I tried putting vacuum to it. Then tried compressed air but it just pushes oil out the small set screw on the side.

What is that set screw for? It has a rubber nose on it but still let's oil past before building enough pressure to push what's blocking the path.

Tormach said to try loosening the gib so the head is sloppy loose and maybe push the block out with air (which is what I'm going to try tomorrow).

I'm wondering if anyone had any similar experience and what their outcome/solution was.

WOTDesigns

[TurboStep]

STOP! You don't know what's blocking the flow and if you loosen the head and blow it through where do you think this unknown "matter" will go? Between the runnung surfaces - just where I wouldn't want it to be!
First things first:
On my series II the hole with the grub screw goes all the way through to the dovetail. The oil is fed through the hole in the top of the slide into this cross hole to feed the dovetail. From the point where these two holes meet a third hole goes horizontally backwards to feed oil to the slide surface. On my machine the grub screw thread appeared to be covered with a rubbery compound which I assumed was just to retain the screw, and perhaps also help to seal the thread.
You didn't say whether one or both surfaces are lacking oil but I was't happy with the amount of oil on the dovetail although the slide appeared to receive enough. There are several reasons for this which I'll cover later.
The first thing that I tried was to remove the grub screw to make sure that oil was getting through this far. Then I fed the the tube of a can of WD40 into the hole in an attempt to flush anything out that may have been restricting the flow. What I got were a few strings of the rubbery compound and a stream of small black particles which I wiped off with a paper towel. I later found that these particles stuck to a magnet! I can guarantee that that was not debris from any milling that I had done (alu and wood aren't magnetic) so I must assume that this was debris from the production of the machine. This is not really what I want between the running surfaces.
Unfortunately work is calling. Will continue later
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[TurboStep]

The Mill has a 15 point lubrication system supplied by 12 lines. Each line has a restrictor which ensures that each line delivers the same amount of oil. One problem with the right side is that both surfaces share a single line and at best each receive one half the quantity supplied to the equivalent surfaces on the left side. On my machine I got the impression that most flowed to the slide and less to the dovetail. I have now modified this system to be able to supply the same amount as on the left side and to distribute this amount more evenly. Unforunately the last step is still on the todo list so I can't post the final results.
One other point to watch is that while the weight of the head is supported by the ballscrew there is also a cantelever effect due to the weight distribution. The weight causes a higher pressure on the lower ends of the slide ways and on the top of the dovetails. This pressure causes a squeegee effect, which wipes off the oil from the dovetails as the head moves down. What you see on the dovetail above the head may not reflect the conditions between the surfaces. This is however one reason why I want to ensure that these surfaces are at least receiving the right amount of oil, evenif I'm not fully able to control its spread.
I had to completely remove the head to make this modification but as I had a bad feeling that I had washed Iron filings between the running surfaces I felt I had to do this anyway.
Just be careful that you don't make matters worse than they really are!
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[philbur]

This uneven oil distribution on the head may be a more widespread issue. My early series 1 has always had significantly less lube to the right side than the left. I previously made a half-hearted attempt to clear the problem (assuming it was some sort of partial blockage). The perceived improvement was more wishful thinking than reality.

Phil

[WOTDesigns]

STEP - pushing left over cast iron into the sliding surfaces is exactly what scared me with Tormach's approach.

The right side shows no signs of oil above or below the head on either surface (slide or dovetail) on the right. Some pools at the Banjo and some seeps from the grub screw and that's it.

I did break one of the Banjo bolts about the 5th time I put it back in and Tormach sent a replacement. 6mm banjo screw that long seems like a very odd size here in the US since no one local (in SoCal) could locate one.

The information that the grub screw is cross drilled to the dovetail is very useful (and annoying that I didn't think of it). I think I will grab some fishing line and try poking across and blasting WD40 a few more times. I did see a bunch of rubber crap come out but didn't think to hit the rest with a magnet, and I don't think I tried blasting wd40 through the cross drilled holes only the top. I will try that this morning and report what comes out... Or goes through)


WOTDesigns

[WOTDesigns]

I would probably be happy with just a perceived improvement. My little X3 has several thousand hours of run time with only a paint brush putting oil on most of the surfaces and has done a pretty good job. I'm already in the habit of a "warm up" including lubrication on the X3 so it wouldn't kill me to keep oiling just the right side on the 1100 too. Annoying, but if that's the worst of what I find I'll be one happy customer still.



WOTDesigns

[Gerry Sweetland]

Don't know if this would help in your case, but Tormach has a Service Bulletin about plugged lube circuits and how to clear them.
But I imagine if you talked to Tormach they already suggested this procedure?
Tormach Service Bulletins | Tormach LLC providers of personal small CNC machines, CNC tooling, and many more CNC items.
Gerry

[SCzEngrgGroup]

I had a similar problem on the knee of my big mill, and it got to the point where the servo would stall trying to move it, even slowly. I removed the oil line fitting from the offending circuit, replaced it with a Zerk fitting, and used a grease gun to force grease in - a grease gun can easily generate 1000PSI or more. That cleared out the clogged oilways, and got the knee moving smoother and freer than it ever had. But if you're concerned about abrasive cr@p in the oilways, I really don't see that you have any choice but to remove the head, and clean the oilways out.

Regards,
Ray L.

[TurboStep]

If your grub screw has a rubber nose on it then it's possible that someone got a little too enthusiastic with the compound and it wouldn't surprise me if that's what's preventing the flow. Removing the head is not easy. I had a vague hope that when I removed the gib I would be able to maneuver it off forwards. Forget it, the slide has to be pulled off the top of the column. I have however just had an idea that might save you a lot of effort (I only wish I'd thought of it a couple of weeks ago!-). When the head is up at the top of the Z the channels are about 4cm below the top of the ways. If you could just lift the head another 5cm you would have access to all the channels from both sides. At your own risk...
Cut a piece of timber to fit between the table and the underside of the head when the head is at the TOP of the Z. This will be about 20 inches long and must be capable of holding the weight of the head. Lower the head to rest on this support and remove the bolts holding the Z motor mount to the column. Then jog the head "further down". This would push the motor mount up. If you can get it up about 2 inches, place a set of 1-2-3 blocks underneath. You should then be able to jog the head right up another 2 inches, beyond the end of the ways, until you can access the channels.
Two problems come to mind. The motor mount MAY attempt to rotate when jogging the head up. This can be solved by using longer bolts to clamp the whole assembly together. The other problem might be the alignment. If you start off too low down in the Z and the 1-2-3 block assembly is clamped together then the alignment may be way out by the time the head has reached the top of the travel, placing a potentially huge stress on the ball nut. This is why I would start off as high as possible.
I've just come up with this idea and haven't tried it. But if you're feeling as stupid as I am, then do it at your own risk (and let us know what went wrong
Good luck
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[philbur]

I've had the head off. It's a 15 - 20 minute job (30 minute for those of a nervous disposition) with no lifting involved.

From memory:

• Disconnect the oil lines and bellows (easiest with the head at the top of its stroke)
• Fit a suitable stud in the front tee slot on the mill table.
• With a drill chuck in the spindle accurately centered it over the stud.
• Lower the drill chuck over the stud.
• Place wooden blocks on the mill table under the head.
• lower the head onto the blocks and tighten the drill chuck on the stud.
• Slacken the 6 head mounting bolts, remove 4 and pull the two locating pins.
• Shake the head to check stability on the wooden blocks.
• Remove the 2 remaining bolts then move the mill table carefully forward with the head sitting on the table.
• You now have access to the Z-axis slide.
• Remove the gib and detach the ballscrew housing.
• Lift the Z-axis slide off the dovetail.

There may be a couple of steps in there that I have forgotten but you get the idea. It all when very smoothly the time I did it. Double check the safety at the critical steps.

Phil

[WOTDesigns]

Thank you both! Thats some damn good food for thought. I picked up some sighing line and I'm going out to try that in a few minutes.

NATURALLY I just got back from picking up 534 #10 screws with Stainless thumb KNOBS already pressed on that need . 5" of threads to be mill/lathe turned down. 10 second cut time, but using a collet and pdb is the only way I can run these efficiently ... And when tgese are done he has 5000 without the thumb knob that need the same thing.

So, I won't be pulling anything off until these are done and that is only if I have a few days free like I thought I did today. I'll let you know what I find.

Thank ks again for the input. I like the idea of pulling the head by clamping to the table. Seems like a pretty easy chore really, but I know better than to do anything easy that could mean I will be waiting on parts to fix when something breaks while I have jobs waiting.

WOTDesigns

[TurboStep]

Phil, I guess I must have a very nervous disposition. I wouldn't want to remove the whole head in one piece. I still have 10 toes and I like it that way
I think you may have missed a couple of diss-assembly steps but did you ever re-assemble it?
I usually take more time to re-assemble and re-adjust than I do to rip apart.
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[WOTDesigns]

Interestingly enough the machine has been off for the last week whole I was out of town. I just pulled the bezel off and there is a perfect coating of oil on the dovetail and way.

I'm going to run it the next few days without oiling directly above the head like I have been doing to see if perhaps the last time I flushed/vacuumed it may have solved it. It's likely that I'm just seeing what's passed under the head from me oiling above the head so I will remove that process and see.

WOTDesigns

[philbur]

Absolute maximum of 2 hours for the round trip, providing you don't spend to much time drinking coffee and admiring your handywork. The worst part was fiddling with the oil lines during reconnection.

Phil

Phil, I guess I must have a very nervous disposition. I wouldn't want to remove the whole head in one piece. I still have 10 toes and I like it that way
I think you may have missed a couple of diss-assembly steps but did you ever re-assemble it?
I usually take more time to re-assemble and re-adjust than I do to rip apart.
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