I did a number on the left hand side of the covers, behind the table, where the chips collect and sometimes cause a limit alarm in very neg Y moves. This time, a 2.5" solid round alum pc got wedged, and bent the lips of a couple of the slides in *over* each other, so now they extend out with great difficulty, actually tugging at the back of the cabinet. goodgawd....
This is some pretty thick stainless, some pcs near 1/8", it appears, and attempts at prying, hammering, etc just aint budging things.
So's here's what I'm about to do, and stop me iffin it's nuts (and not too late):
I've got the O/A torch out, to heat the spot cherry red (just a square inch or two, over the bent lip), and I plan on moving the table to the front (+ Y move), to extend the slides, whilst pounding/prying the area flat enough so that at least it can extend without bending the back of the cabinet.
Goodgawd, it makes my teeth hurt to even describe this....
I was also thinking of just cutting/grinding that area out, and maybe epoxying some plastic/nylon in its stead.
Packed chips behind the table did a number on the seals some time ago, as well. I cover the whole business with a black garbage bag.
I got bent Z slides also, cuz shit is just hanging out all over the table, and it's hard to keep track of what is where. But these are not as much of a problem.
Fadal said it's miserable expensive to replace these covers, and to just try to live with it. Hopefully not too much shit is getting in there to screw up the ball screws.
It seems as tho the first slide section bolts on to the back of the cabinet,
4 bolts. Good.... BUT, this slide section has bottom lips, so it can't just be lifted straight off. Will it bend sufficiently, so that I can lift it off? Seems like it must, to have gotten them on....
Any experience out there with this?
If I could get a couple sections off, I could hammer them on an anvil, or mebbe stick them in an arbor press or sumpn....
Don't think I'll be heating anything cherry red just yet.... :)
Mebbe I can even perhaps repair the lesser-bent slides/seals from those packed chips.
those slideway covers are a real real bitch- believe me I KNOW- prevention is far far better than the cure; there are shops that specialize in repairing damaged slideway covers- your machine will be idle for up to 2 weeks, then the repaired slides are installed and you have to go easy for awhile while they "break in"- 6 months later, they start to come apart- so you spent as much as a third the cost of new covers repairing old ones but 6 months later you'll cut your loses and shell out for new ones. You basically have to get new ones; one way to protect the covers is to place rubber mats on top of the covers, this will help keep chips from getting caught under covers as they slide together. if you don't shell out now, you could find out the cost of the accumulated damage to ballscrew, motor etc is a lot more.
those slideway covers are a real real bitch- believe me I KNOW- prevention is far far better than the cure; there are shops that specialize in repairing damaged slideway covers- your machine will be idle for up to 2 weeks, then the repaired slides are installed and you have to go easy for awhile while they "break in"- 6 months later, they start to come apart- so you spent as much as a third the cost of new covers repairing old ones but 6 months later you'll cut your loses and shell out for new ones. You basically have to get new ones; one way to protect the covers is to place rubber mats on top of the covers, this will help keep chips from getting caught under covers as they slide together. if you don't shell out now, you could find out the cost of the accumulated damage to ballscrew, motor etc is a lot more.
Actually, more just shitty/dirty/contortionist grunt work than anything else, and def'ly not for the very overweight or feint of heart. goodgawd...
Ahma be plucking alum/brass splinters out of my g-d ass for days.... well, the wife will be plucking them out, actually....
So here's the deal:
Reamman is certainly not far off.
Once the whole unit is off, each section disassembles perty neat, altho my bent sections were a bitch. And yes indeedy, yer flavorite hack machinist was right: Hadda arbor press shit first, to flatten the bent edges, to even get it apart, so mashed were they.
But none of this is even the real problem!!!
The REAL problem is that the seals/wipes on *every slide section* had rotted/brittled out!
Now, what they *should* have done is put in hard-temper copper/brass sprung seals, which you'll find in very old high-quality weather-sealing in old doors/windows.
Or, used actual springs to load a bronze or nylon/delrin wipe-bar. This would have required slightly increased overall-dimensions of the slides, to accommodate springs/travel, etc, but it would have been a nice, elegant, and
*permanent* solution -- and fixable! God effing forbid, right?
Or AT LEAST make the shit replaceable, like windshield wipers.
I was thinking of laying beads of 100% silicon caulking where the seals were, but the nature of this beast is that that will likely be short-lived.
So, it looks like what ahm gonna do is bang/bend things back into shape as best as possible, and put my garbage bags back on. If I could find nice rubber or accordion stuff, I'd use that, but for now, the bags will do.
Indeed, some amount of crap/chips/gunk accumulated beneath the ball screw, but the ball screw looks good. Wouldncha know, I dumped a whole pile of crap on the ball screw, so now I gotta clean DAT meticulously.
Cupla Qs:
How much crap in there is permissible/normal?
What are the nylon thingies coming down from the slide covers, that sort of look like wipes for the ways? Each slide section has a left and right wipe, but this use doesn't quite make sense, as I don't think the overall accuracy is there for these to serve as wipes.
This will teach me to leave loose pieces of metal floating around inside the cabinet.
If anyone knows of an aftermarket product that might function as a decent seal, give me a holler.
This shit is taking the better part of an 8 hour shift.... and that's just the *back* Y slides -- not the front, or Z, or X, or anything else!
All the ball nuts that I have seen have a seal of some sort, so while chips are never a good idea the nuts are generally pretty well protected.
If yo do get it fixed what I do is to hose down the covers at the end of the day. I think the seals get a lot more abuse from being run over chips that have dried and become adhered to the covers.
the "repaired" covers had brass shims attached to help them slide- the big danger is when the covers start to walk- that is, the don't open and close evenly, one end gets bent further open and soon enough they separate. what you can do is get this thick rubber mat, tack one end to the back of the machine, and the other to the table, it will keep chips from falling into the machine, it's not a permanet solution, but will help- just have to sweep the chips and keep them from accumulating
I know a guy up here that replace some wipers on a lathe. The wipers were real nice quality. Not cheap, but a lot cheaper than the OEM stuff. He's downsized radically and doesn't seem to be around the shop much lately, but I'll see if I can't get ahold of him and ask if he remembers where he got the stuff.
If you don't get the sheetmetal real straight though, quality wipers might be a waste.
the "repaired" covers had brass shims attached to help them slide- the big danger is when the covers start to walk- that is, the don't open and close evenly, one end gets bent further open and soon enough they separate. what you can do is get this thick rubber mat, tack one end to the back of the machine, and the other to the table, it will keep chips from falling into the machine, it's not a permanet solution, but will help- just have to sweep the chips and keep them from accumulating ====================================== =========================================
Mine has those brass shims, but only on the sides. The long horizontal top seal had crappy sheet metal spot welded to the stainless, and bent over to hold the crappy wipers/seals.
I suspect that some formulas of coolant are tougher on these seals than other formulas, as well. This machine doesn't have that many hours on it for every g-d seal to be gone.
My garbage bag does the job of your rubber mat; when I find some rubber, I'll do a better improv, but for now the bags work.
I think properly draped plastic/rubber *could* be a permanent solution. The SS slides provide the basic mechanical protection, and anything that is moisture-tight provides the chip protection. Mebbe not assthetic, but functional/serviceable.
A 4+ hour job with a helper, really a back-breaking messy pita.
But, it's real nice to be able to move in Y now, without watching the whole g-d cabinet sag in and out! :)
However, I just don't have it in me to do this whole thing again -- plus the down time, because as someone pointed out, I'd proly need these covers professionally re-done if the wipers are to be effective.
And altho reamman calls these rubber mats (or my garbage bags) temporary, I think properly done they would be a *better* solution to repairing the teleflex's themselves, or even new teleflexes, as the two functions are now distinct and separate:
Mechanical strength from the teleflex covers, and liquid/chip/dust proofing from the rubber/plastic.
In fact, if the garbage bags weren't so ugly and fragile, they seem to form the best seal of all!!
Perhaps some good "prevention" would be to put these garbage bags in place when the machine is new, *before* the seals wear out!
Inneresting note:
Fadal provides a drain for this area under/about the Y ballscrew/ways, AND this drain can and has become clogged -- if you see flooding about the back of the machine, and cain't figger out where it's coming from, the two sources I've found are this center drain outlet, and splashing from the centrifugal pump when the coolant gets too low -- about 3-5" from the chip pans, in my case. Which doesn't seem that low to me, but the coolant loss from said splashing is quick indeed.
But the point to the above was, that Fadal IS making provisions for drainage from under the Y way covers, and where dey's coolant, dey is chips! fwiw.
Also, much of the cabinet uses effing *caulking*! goodgawd.... This too can spring a leak, depending on how hard yer flood coolant is going, and how it's aimed.
I don't know what you are machining, in my case it was tool steel ( d2, a2, mild steel mostly)- the chips would melt garbage bags before landing on it, but you are right about using prevention from the start- which is what we did with the new covers in both places where I worked when they failed ( I had nothing to do with their failure, only the cure). Coolant does evaporate too; depending on how much misting and dry the environment is- usually we had to throw a few buckets of water into the tank every other day or so- but whenever I had to open up the machine, I never found an excessive amount of coolant anywhere, so if your're worried you have a large quantity of coolant inside the machine where it shouldn't be I don't think you need to worry that much- it releases the water and leaves behind a sticky residue that seems to protect metal from corrision.
There are a ton of different ways to protect your machines. I am not sure where about in the world you live but we at Corwhin Tool
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have repaired covers from as far away as Mexico and we're near Toronto. It is certianly a large problem but one which I believe can be fixed. Why don't you check us out and give us a call. We, like many other companies, can do a turn round in less than the 2 weeks mentioned if needed. Emergency covers, for example, can be turned around in a day and Rush covers with in 2 days depending on the amount of work needed to be done. Our Engineers and staff are very familiar with lots of the covers and we have some new and repaired ones in stock if you want to swap one out or get a spair.
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