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Thread: Italian mystery mills, and spindle bearings therein

  1. #1
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    Question Italian mystery mills, and spindle bearings therein

    They say the first step toward recovery is admitting you have a problem and need help.

    Well, I've got a problem and need help (quite a lot of problems, actually, that almost certainly need "professional help" - but most of those aren't really on topic), and this seemed like it might be a more forgiving place than [machining forum], had less invasive membership requirements than [other machining forum], and, being nostalgic for old dialup BBSes of yore, I just kinda liked the domain name better than [what, another machining forum?]. So now you're stuck with me.

    First, a bit of backstory (since this almost certainly won't be my only question about the machine):

    Lately I've been occupied rebuilding (or at least cleaning, reassembling, and attempting not to further damage) an odd little Rambaudi vertical frankenmill that I picked up a few months back... both oddly little, at least for a Rambaudi, and a little odd all around - even before the heavy frankensteining it seems to have suffered. It's also a bit of a mystery - aside from a few "what is this thing?" threads by prior owners (like this one on P.M, with pictures from two owners ago - I don't have any fully assembled pics of my own yet, as it hasn't been assembled since coming home) I haven't been able to find any hint that Rambaudi ever made anything that weighed much under a ton, much less a petite lil' 600lb cutie like Miss Frankie Rambo here. Lathes.co.uk has nothing, and, while I have yet to track down anyone at Rambaudi to ask, the fact that they've changed ownership a few times (passing at least briefly through Taiwan) doesn't give me much hope for that route.

    To put that a little more concisely: there ain't no manual.

    Of course, if there were a manual, it might still not help, considering the number of parts that are either obviously shop-made (given away by the subtle lack of the "45" stamped on every other part, and the rather less subtle cavemanlike construction), or in somewhere other than their intended location (compare the nameplate pulley & motor diagram to the actual pulley arrangement). This also makes for an interesting mix of metric & SAE fasteners and "Made in Italy" & "Made in USA" stamps.

    It's partly due to one of those "Made in USA"-stamped parts that I landed here and started rambling. After dissecting, cleaning, occasionally replacing, and reassembling just about everything else in the mill, I finally made it to the important bits. With several days of puzzlement, profanity, and just a touch of wanton violence (mostly between my forehead and any convenient walls), I figured out how to extract the spindle, and cleaned off the grease of ages (as applied through the probably-not-really-for-grease zerk on the front, and generously seasoned with the dust, grit, and chips of ages).

    Now, stumbling slowly and painfully toward the point...

    The lower spindle bearing (80mm OD, 40mm ID, 30.2mm thick, stamped "FEDERAL / 5208 / USA" - clearly not factory issue) has a few balls that aren't bearing up so well, with rather cracked or grooved looking finishes, and it occasionally crunches in a not exactly bearinglike fashion. The upper bearing (62mm OD, 30mm ID, 23.8mm thick, stamped "MADE IN ITALY / BAANOR / RIV- / ??M"... or something vaguely like that) has less visible damage, but is also a little crunchy. They're both double row, unshielded ball bearings. It's possible (likely, even) that I still haven't quite gotten all the crud cleaned out and that it's contributing to the crunch, but I've got an unpleasant premonition that after I hit 'Post' on this I'm more likely to be hear "they need to be replaced" than "that's how you know your bearings are healthy!".

    Assuming I'm not met with a lecture on what a heartless bastard I am for not accepting bearing balls that are born with deformit...born 'different', and how more enlightened machinists know that crunchy sounds and rough spots are just the natural way bearings express themselves (which is ok - if that's what society now accepts, I'll admit my heartlessness and try to change my evil ways... just as long as it saves me the hassle and headache of replacement), the big question is what kind of replacement bearings do I need? I can find 5208s of the expected dimensions - with or without seals or shields - in a variety of flavors and priced anywhere from $12 (which just doesn't painful enough to be right) to $120 (which I hope is more painful than needed), but have little idea what I should be looking for (or even if that's the intended bearing - it looks like the shaft took a fair bit of abuse from someone trying to either force it on, or make it stay on). And, of course, for the Italian upper bearing, I don't even know where I'd start.


    There are, of course, other related questions, and there will, inevitably, be other unrelated questions (did I mention this is also my first mill?), but you already deserve a reward if you read this far, so I'm going to shut up.


    -Bats

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    It's not clear yet what mechanicing or machining skills you have but you sure can write. That was quite the manuscript you put hammered out for your first post. My emotions were all over the place as I read it. Me thinks you could be a writer if this machining thing doesn't pan out.

    Include applicable photos if necessary with your post, a picture speaks a thousand words. I use imgur to host my photos. Also, this post would get more action in the general section because there is more traffic.

    In the early 1990's I bought an odd ball Italian lathe called a SAIMP from a machine tool dealer in California. It came with nothing other than an incomplete taper attachment and lever action collet closure. It was in pretty good condition but I wanted a manual for it just because. Tony in the UK had never heard of a Saimp anything. Ten years later I was in Switzerland on a job and just happened mentioned to an Italian engineer I was working with that I was looking for a manual for my Saimp lathe. Two months later I get a pdf file of the complete manual in my email. The point is, manuals are available for just about any machine but it takes time and a bit luck to find one. And! another thing, Rambaudi's are much more common machines than Saimps.

    Sorry, no help with your bearing issue.

    Ron

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    That spindle appears to have been welded up and remachined.


    How are the bearings preloaded (if at all) and how are they retained in the spindle housing?

    you might have a lot of options if you're willing to experiment a little. for example, the lower bearings you could replace with two 6208 bearings. put a spacer between the two outer races and epoxy the inner races to the spindle, while its curing put maybe 30 pounds of force pressing the inner races together, this will preload the bearing but it will only be as strong as the epoxy. so don't put more than 500 pounds axial force on the spindle! for the upper bearing a single 6206 bearing will work.

    This will get the mill operational immediately for nearly zero expense except for the time and trouble to figure out how to re-install the spindle (the two 6208 bearings will be 36mm thick instead of 30.2mm)


    you may find you need to make a new spindle, or at a minimum regrind the taper.
    Last edited by johansen; 03-12-2019 at 02:15 AM.

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    Quote Originally Posted by nc5a View Post
    It's not clear yet what mechanicing or machining skills you have but you sure can write. That was quite the manuscript you put hammered out for your first post. My emotions were all over the place as I read it. Me thinks you could be a writer if this machining thing doesn't pan out.
    Writing's easy. The problem, as you may have noticed, is stopping.

    Mechanicalizing, on the other hand, I'm only about four year in to fumbling around the edges, after spending most of my life working strictly in the virtual.

    Include applicable photos if necessary with your post, a picture speaks a thousand words. I use imgur to host my photos. Also, this post would get more action in the general section because there is more traffic.
    Aside from the link to the PM thread with the prior-owner-minus-one's pics, the rest of the links were to pictures. I'd originally inserted them inline in the post, but after realizing these forums don't resize or auto-thumbnail (and having already gone through one cycle of resizing, and being on the second rewrite of the post after a bluescreen crash and autosave failure relegated the first to whatever heaven exists for unposted posts, and just generally having questionable judgement on such things) and that at 1024x768 they gave the impression of inflating a novella of a post into full blown Tolstoy territory. Or, well, they would have if Tolstoy had been known for including pictures of greasy machine tools in his work.

    If you think it's worth it, though (and if it's not taboo - I've skimmed occasional threads here for the past few years, but only recently started trying to grok the local customs), I'll see about tossing an inlined version over on General.

    In the early 1990's I bought an odd ball Italian lathe called a SAIMP from a machine tool dealer in California. It came with nothing other than an incomplete taper attachment and lever action collet closure. It was in pretty good condition but I wanted a manual for it just because. Tony in the UK had never heard of a Saimp anything. Ten years later I was in Switzerland on a job and just happened mentioned to an Italian engineer I was working with that I was looking for a manual for my Saimp lathe. Two months later I get a pdf file of the complete manual in my email.
    So... basically your point is that I should go hit up Priceline and reserve tickets to Switzerland for March 2029, then look for an Italian willing to work with me? Got it!

    The point is, manuals are available for just about any machine but it takes time and a bit luck to find one.
    Oh. Or that.

    And! another thing, Rambaudi's are much more common machines than Saimps.
    True, but that also makes it all the more puzzling. Finding, say, a 7x12 mini lathe from a company no one's ever heard of wouldn't surprise anyone... But if that was a vintage Bridgeport 7x12 mini lathe, the fact that such a thing existed would be a shock in itself, but the fact that no one had ever realized such a well known company had ever sold anything of the sort would be even more of one.

    I don't think this one's quite unique - in addition to the majority of the parts being stamped "45", I've also found at least two "48"s, leading to me to believe there had to be at least two of these things (if not a full 48) - but, short of finding a contact at Rambaudi with a historical bent maintaining a hidden library of ephemera, I'm also not really expecting a manual to turn up in time to make a decision on the bearings. I would be fascinated to know how the whole thing was actually designed to go together, too, and whether either of the nameplates even belong to it (a close inspection of the pics here reveals that they not only show two different pulley/motor configurations, but also specify two entirely different motor speeds and distinctly different notation for HP. the "Rambaudi & C." nameplate at least matches stamp in the casting, though, which is slightly less convenient to swap between machines).

    On that note, I did just stumble across an Italian machine tool dealer a couple hours east of Rambaudi's old home in Turin, who claims to have been in business since 1919. I'm hoping they might know something - or know someone who might know something - about the more historical elements of the puzzle.

    Sorry, no help with your bearing issue.
    Well, at least now I know what country to travel to in ten years where I'll spontaneously find someone who'll eventually send me a manual, so it's not a total loss.


    -Bats

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    Quote Originally Posted by johansen View Post
    That spindle appears to have been welded up and remachined.
    So you think that deep black squiggle is a remnant of welding rather than casting? It also seems to align with a (less irregularly shaped) bit of keystock on the inside of the taper, which looks like it's meant to be a depth stop (is that sort of thing normal in R8 tapers?), which may not be related.

    I suppose if the entire spindle assembly had been rebuilt it would explain the end caps being so roughly finished inside, the haphazardly spaced pin spanner holes, and the suspicious lack of "45" stamps on any of the pieces, and the fact that the lower bearing overlaps about a third of the endcap threads. This (not inline due to excessive size) pic also shows rubbed off grease at exactly the same point the stamps were rubbed off the bearings, suggesting something was in contact where it shouldn't have been. It's much neater work than the other modifications, though - except, of course, for that squiggle and the file/chisel/smears around it.


    How are the bearings preloaded (if at all) and how are they retained in the spindle housing?
    I suppose I could see an argument that the shoulders on the spindle/housing and the endcaps & nut function together as a crude sort of preload, but aside from that, they're not. As for retention, hang on for a photo album...

    This is what the whole assembly looks like:



    The round bit at the top is part of the casting and used to mount the pulley guard/tensioner dovetail casting (not shown), while the round bit at the bottom is part of the spindle liner or housing that fits inside the casting (which is held in place by six screws, removed, and black magic, still in place).

    The bearings press into the top & bottom against shoulders and the discs (at top & bottom of the first pic) are endcaps that screw into the casting and liner (respectively) which are threaded like this (top shown - the bottom is fairly similar):


    The nut then screws onto the threads at the top of the spindle like this (with, of course, a pulley over it and drawbar inside it):



    you might have a lot of options if you're willing to experiment a little. for example, the lower bearings you could replace with two 6208 bearings. put a spacer between the two outer races and epoxy the inner races to the spindle, while its curing put maybe 30 pounds of force pressing the inner races together, this will preload the bearing but it will only be as strong as the epoxy. so don't put more than 500 pounds axial force on the spindle! for the upper bearing a single 6206 bearing will work.
    Any particular reason for switching to three single-row bearings instead of the two double-row, or from the angular contact 5208 to deep groove 6208/6206? Is it just cost (the cheap end of the 5208s looked pretty damn cheap, and even the midrange was, if not an impulse buy, at least affordable) or is there more to it than that? Aside from some time & trouble, what am I looking at sacrificing if I go that route? Or, for that matter, what is there to be gained/lost if I just replace the lower 5208 with a new expensive/cheap/average 5208 (and the upper with... errr... something that looks vaguely similar to whatever's on there)?

    If asking this makes it look like I really don't know my bearings, that's purely an illusion brought on by your overactive imagination and the fact that I really don't know my bearings.

    This will get the mill operational immediately for nearly zero expense except for the time and trouble to figure out how to re-install the spindle (the two 6208 bearings will be 36mm thick instead of 30.2mm)
    This worries me a little - at least at first glance - as the 30.2mm bearing already overlaps the threads for the lower end cap, and pushing it to 36mm would give the cap maybe one full thread engaged. Assuming I found the confidence, competence, and tooling to remachine the liner, that end still only has about 1/2" of material between the shoulder the bearing mates with and the point where it necks in to enter the casting - and that seems like a Really Badô place to go skimping on strength.

    you may find you need to make a new spindle, or at a minimum regrind the taper.
    Ugh. I guess I shouldn't have kept putting off that steady rest purchase.... or troubleshooting when I noticed the South Bend was starting to taper where it shouldn't. I guess I also shouldn't have completely blocked in the South Bend with tool carts and castings when I was trying to make room to work on Frankie Rambo. I could probably also add something about a general lack of confidence in my abilities, too, but I figure the list of spontaneous excuses probably makes that clear enough by itself.

    But, before I get too carried away with excuses and inadequacies, are you suggesting it'll just flat out need to be replaced/reground regardless, or just possibly to accommodate the different bearings?


    -Bats
    (if more and/or higher resolution pictures of anything are likely to be helpful, just ask. I've got just about every part, in just about every stage of disassembly and cleaned up. I can even take more pictures. please! look at my pictures, dammit! don't make me feel like a poor lonely grandmother when she can't find a helpless and unsuspecting stranger that can be locked into their bus seat and forcibly subjected to her 400lb album of ugly baby photos!)

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    The way that spindle is made the bearings can't be preloaded.

    i would replace them with relatively cheap 5808 and 5206 bearings.

    if there is still too much axial/radial slop in the bearings then buy a more expensive lower clearance 5808 for the bottom.

    anyhow get some v blocks and a test indicator and verify it isn't bent.

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    Quote Originally Posted by johansen View Post
    i would replace them with relatively cheap 5808 and 5206 bearings.

    if there is still too much axial/radial slop in the bearings then buy a more expensive lower clearance 5808 for the bottom.
    Any guidance on calibrating the relativity of my cheapness? "Grab something out of a cracker jack box & then upgrade to 'toy' grade if it's too sloppy"? ABEC-x? "Give til' it hurts, but stop short of bankruptcy"?

    The 5206 looks like it's a match (at least size-wise) for the upper one, but am I right in guessing that "5808" was meant to be a "5208"? The only 5808 I can find mention of is a CRI-5808 tapered roller bearing that's 290x400x120mm, and might require a little creativity to fit on a 40mm shaft in an 80mm housing. That, or a really, really big press.

    On a related note: A lot of sites seem to list the 3200 and 5200 series as identical substitutions. I get the impression that's not actually true, but are the differences significant enough that I need to care?

    anyhow get some v blocks and a test indicator and verify it isn't bent.
    I knew I was going to kick myself for passing up that cheap lot of step & v-blocks...

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    yeah i meant to type 5208.
    there are a number of them on ebay, nos about 30$
    the 5206 bearings are cheaper, more options. i'm not sure i would buy a cheap one from china for 9$ though.

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    Quote Originally Posted by johansen View Post
    yeah i meant to type 5208.
    there are a number of them on ebay, nos about 30$
    the 5206 bearings are cheaper, more options. i'm not sure i would buy a cheap one from china for 9$ though.
    I guess that was the real question - whether to go for just-kinda-cheap or are-you-sure-that-price-isn't-for-an-empty-cardboard-box?-cheap. If the specs aren't important, yeah, it looks like I can get both domestic (either Federal-Mogul to match the not-actually-original bearing, or Fafnir to match the also-not-original pulley bearings) for under $50 shipped, which is probably about what I paid just for gas to bring the machine home.

    Any idea whether there's a good reason they previously went for open over shielded (or which would be better for a replacement)? There's a zerk (previously used for/clogged by grease) in the casting about a third of the way up from the lower bearing, but basically no access to the upper bearing at all without removing the pulley & end cap, so using something that doesn't require regular lubrication would seem to be the intuitive choice... but I suspect my intuition's lacking in a fair bit of important bearing theory.


    -Bats

    ( ebay's "browse related" selections were all Build-a-Bear related. I guess smooth joint movement is more important than cuddlyness and lack of grease in today's teddy bear market )

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    Perhaps I am looking at a different part, but the bearing balls I see in the picture do not look so bad. They have a little more scratching than usual on the very best bearingss, but they are "used".

    The bearing itself appears to be a double row, and may likely be a "zero clearance" or "internally preloaded" bearing, similar to what was used on Logan lathes.

    They do appear to have the remnants of ancient grease still stuck to them in places (the dark stuff). That can be removed. I tend to use lye-based cleaners, because they have no tendency to rust anything or otherwise discolor steel.

    I have heard of people using Pine-Sol, and swearing it cleaned everything up perfectly, but cannot confirm that. It discolored the only bearing I ever tried it on, and I will not use it ever again unless someone can explain the discoloration in a satisfactory way.
    Last edited by J Tiers; 03-15-2019 at 09:11 PM.
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