[RustedOut]

Hi All,

After converting my IH mill to CNC, I never bothered reinstalling the bellows that covered the ways on the column. It had pretty much collapsed. I did install the rubber or flexible plastic cover that stretched from the back of the saddle to the area just below the vertical ways. It's now broken in two or more pieces from getting trapped between the back of the Y ways and the column. I've thought about filling those gaps with bondo or silicone or something similar to prevent that.

But at this point, it doesn't seem too sensible to put another rubber pad back there and I have found myself looking for alternate solutions. One that is attractive to me is a telescoping way cover. I'd think that one could run from the back of the saddle up to and attach just below the head where the old bellows connected. I know they're probably not dirt cheap, but at first blush, they look like a good solution. Anyone done this or done some other slick solution?

Bob

[Cruiser]

I have been running mine without any protection at all other than a vasectomy !

[RustedOut]

Funny Don,

Yesterday I made a cover for the front of the bed across the Y ways. Made it from 18 gage steel, bolting it to the four tapped holes along the front of the saddle. I thought it was going to work out good except it was drooping some in the front end. Got the bright idea to brace it up to the back flange and screwed it up welding in a couple of gussets. Tomorrow I'l make a new one with better made gussets.

The more I look at the vertical ways and the back of the saddle, there isn't much room back there when the bed is at the rear most position. Looking at some inexpensive way covers on the net the past couple days, but they would take up a lot of the precious room back there. A roll down cover would be the best fit I think. One of the folded variety may work ok, but to buy one is a pretty big investment without knowing it'll work. Still searching I think.

Bob

[RustedOut]

Got some photos of a way cover I thought might be a candidate with some modification. The thing just got too thick in the stackup of pieces. So, I gave up on the telescoping cover and went with a rubber sheet stretched from the saddle to the bottom of the z slide. I also added some rigid foam between the back of the ways and the column to keep the cover out of there. A photo or two follows. Not got back to the new front way cover, maybe tomorrow.

Then it was on to a more pressing problem, excessive end play on the x and y ballscrews. Not real sure what is the prime cause, but the bearings are allowing around .007" end play. When the mill was first put into service, there was virtually no end play there. Not real sure how many hours is on the mill right now, but no more than 100. Really disappointed in that performance. Probably originally installed with a gap between the inner races and just recently got wore enough to show up.

I had some new bearings I bought some months ago and removed the originals and installed the new and they give me .0015" end play with no grease. I don't have any grease for the new bearings so I've ordered some .001" and .0015" thick shims to fit and believe I'll go ahead and try to adjust the old bearing to no end play so I can learn a little more about that process. After all, I don't have a maintenance service I can call on to keep this thing running so knowing everything about it and how to fix it will be beneficial down the road. While I'm waiting on the shims, I'll take a look at the Z bearings.

Bob

[Runner4404spd]

on the end play of your axes, i think you'll find some of the bolts that hold the spring washers in places are looser than expected. these bolts are not supposed to be tight as they allow the washer to compress to impart preload on the ac bearings. you need to seat the bolts until the washers are just flat and no further. if you can you may want to unscrew the bolts and apply loctite to them.

[RustedOut]

Those were the second thing I checked. Right after the ball nut preload nuts. The bolts seemed ok, but I did loosen them and retighten. I had cut off an allen wrench during the conversion to be able to get to them with the pulley's on. Funny how loose they really are installed. And they were locktited. No improvement on the backlash. Then I figured the pulley had loosened allowing some end play. Checked that today and no problem with the pulley.

That's what got me deeper into the bearings, eliminating things as I went. The backlash measuring the table travel at the spindle was the same as the end play I was getting measuring from the pulley face, exactly to the half thousand I could measure. I used a dial indicator and a last word indicator so I could map both at the same time.

Found some mobile grease at Grainger's, so may go pick some up tomorrow and just install the new bearings. Going to be in their neighborhood anyway in the morning. Not really wanting to wait on the shims to get it back into service, but they'll be good to have on hand as will the grease.

Bob