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  • Making a tiny filing rest

    I've been really dragging my feet on this project, so I thought I'd start a thread to keep updated as I make progress, to keep me motivated to work on it.

    I'm making a filing rest for my swiss pattern watchmakers lathe. It has a "D" shaped bed that is sort of a pain to make attachments for (not nearly as easy as the American split bed type), so some time ago I made a little T slotted base to fit onto the bed, to which I could make other accessories to fit. This filing rest will be the second accessory I've made to fit that little base.

    I really wanted two features on this tool: Graduated height adjustment, and double rollers (I never really understood the point of single roller rests). I'm sort of winging the design - I made some sketches and wrote down some calculations but that's about it.

    Unfortunately I didn't start taking pictures until after I had finished making a few of the parts. So far, everything has been made from O1 rod and O1 flat stock. First picture I took was turning one of the roller pins on the lathe, with the rollers and the other pin laid out on the cross-slide:


    I really should have taken a picture while milling the body from 3/8" flat O1 stock - I used a small end mill in my little Barker PM. Here is the body after being roughly milled to shape, before being laid out and drilled for the pins. You can also see the threaded holes I'm using in the ends of the pins - I'm planning on making up a pair of M1.6 screws with big heads to retain the rollers... I may need to put some polished washers between them, we'll see.


    The necks of the pins, to be a press fit in the body, are 0.218" in diameter. I laid out the body for the pin holes, drilled pilots, drilled out to nearly the final diameter, then made up a 0.216" spade drill to take them to the final size (those little spade drills make beautifully finished holes that are much better than any twist drill I've used). 0.217" probably would have been better, I had to use a little more force than I would have liked to drive the pins in.

    Here's the assembly with the rollers set into place:


    I think it's starting to look like a filing rest, but now I need to make all the fiddly parts for the base and adjusting mechanism.
    Max
    http://joyofprecision.com/

  • #2
    Excuse my ignorance, but what is a filing rest and how is it used? I take it that it is a lathe attachment. Does a Swiss pattern lathe not have a carriage? Can we see a pic of the lathe? I do clock work, bushed two barrels and one plate this AM. Use a Unimat and a Jet 9X20 for most things. Also made a barrel cover since Iseemed to have misplaced it. I have been looking for a jewelers lathe for many years, but they are pricey. Bob.

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    • #3
      Originally posted by Bob Fisher View Post
      Excuse my ignorance, but what is a filing rest and how is it used? I take it that it is a lathe attachment. Does a Swiss pattern lathe not have a carriage? Can we see a pic of the lathe? I do clock work, bushed two barrels and one plate this AM. Use a Unimat and a Jet 9X20 for most things. Also made a barrel cover since Iseemed to have misplaced it. I have been looking for a jewelers lathe for many years, but they are pricey. Bob.
      Hi Bob,

      Used on a lathe, filing rests are a great, low-cost and simple way of performing certain simple milling operations, especially if you have an indexing headstock (or even better if you have a true dividing attachment for the headstock). When you do see them used (which isn't often these days, it seems), it's usually for filing a portion of round work square (for example, to square the end of an arbor that needs to engage a square hole). If you have a good one with accurate height adjustment you really can do a lot with it. I don't reckon most modern machinists would get use out of this sort of thing, but I rather like the idea of using one for certain tasks (call me old fashioned, I guess).

      You are correct about the lack of a carriage - it's not just the swiss pattern machines though. Jeweler/watchmaker lathes, and their bigger cousins (sometimes referred to as "instrument" lathes) are plain turning lathes. They are capable of threading and power feeding, but the attachments for that are fairly rare and quite expensive when they do surface. A gear train mounts to the back of the lathe bed, engaging with a gear on the headstock spindle, and that drives a telescoping driveshaft with two universal joints, that is attached to the rear of the leadscrew for the top slide of the compound rest.

      This is my second watchmakers lathe, my first was an old Rivett that was beautifully made but severely lacking in the tooling department. This one is a Sincere C6104, that's a Chinese make. It's a great little machine if you're willing to do the finishing work that the factory couldn't be bothered to do themselves. It comes from the same factory as the Vector lathes (a German brand, if I recall correctly) commonly found in watchmaking schools, but the finish quality on the Vectors is much, much nicer. Here is a pic of mine, right after I unpacked it - it came with a great milling/grinding attachment, lever feed/collet holding tailstock, and a set of indexing plates for the headstock.
      Max
      http://joyofprecision.com/

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      • #4
        Jere Mihalov's excellent blog has a great post about using the filing rest in a traditional fashion, for squaring one end of a winding arbor (he actually made a replacement set of rollers for his factory-supplied rest, that applied a slight taper to the work): http://watchmaking.weebly.com/barrel-arbor.html
        Last edited by mars-red; 05-05-2013, 06:51 PM.
        Max
        http://joyofprecision.com/

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        • #5
          Thanks, Max, I never thought about filing a square as a use. Does this thing need to be hardened to hold up long term? ,like to see a pic in operation. Bob.

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          • #6
            hi i have a boley and a levin watch makers lathes i was lucky enough to get a filing rest with both of them when i aquired them 30 years ago all i have ever used them for (rests) is putting a square on a turning. mostly stems for watch repair

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            • #7
              Originally posted by Bob Fisher View Post
              Thanks, Max, I never thought about filing a square as a use. Does this thing need to be hardened to hold up long term? ,like to see a pic in operation. Bob.
              Yep, the rollers will need to be hardened. I'll be leaving them glass hard to keep the files from chewing them up. The pins I will harden and temper to blue, and same for all screws and levers that I end up making for it. I really enjoy heat treating small parts, so I'll probably end up doing the same for the parts that don't really need it, too (like the body).

              I'll be sure to show some pics in use after I finish this thing, but you can also see a filing rest in use on the page I linked to above. You could try searching youtube, it wouldn't surprise me if there's a video or two kicking around showing a filing rest in use.

              Originally posted by 257 View Post
              hi i have a boley and a levin watch makers lathes i was lucky enough to get a filing rest with both of them when i aquired them 30 years ago all i have ever used them for (rests) is putting a square on a turning. mostly stems for watch repair
              I sure do like those Levins! They make some fine machines. It does seem that winding stems are the stereotypical use of a filing rest. I make a lot of small screws, and sometimes use a screwhead slotting file to form the slot - they're great for that as well. Also handy for making "D" shaped reamers (my Sietz set is missing a few sizes).

              I'm glad you guys have commented here, it's great to hear from others on the forum who are into watch and clock work. If you guys have any projects posted up here or on one of the watch/clock sites, let me know. I always like to see what people are up to!
              Max
              http://joyofprecision.com/

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              • #8
                Google Images search for "filing rest" examples: http://www.google.com/search?hl=en&s...mg.JAVHYSf6xuU

                David Merrill

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                • #9
                  More questions, do glass hard rollers have a dulling effect on the files? That is a sweet looking lathe, what kind of $ are we talking? Thanks for the replies. Bob.

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                  • #10
                    Originally posted by Bob Fisher View Post
                    More questions, do glass hard rollers have a dulling effect on the files? That is a sweet looking lathe, what kind of $ are we talking? Thanks for the replies. Bob.
                    If they're functioning properly, they shouldn't be tough on the files. We're also not talking about a lot of force here, as the rollers are just a rest/guide. When starting the filing operation, there is no need to have the file contact the rollers at all, it's only toward the end of the operation that they'd be seeing much contact, I think. That's just speculation, as I haven't used one of these myself yet.

                    For the money it really is a sweet machine... as long as you realize it isn't ready to run. What I really wanted was a "kit"... if I could have purchased a casting kit for one of these lathes with the various attachments, I would have... after doing some research about these Chinese machines they seemed like the next best thing. Firsthand reviews said the bearings were good, and tailstock alignment was good... those were the really important things so I decided to go for it. It was better than I expected, for sure. The lathe with all those accessories/attachments was right around $1k, and I paid a little extra for some metric collets to go with it. IIRC, the vectors are in the ballpark of $5k, similarly equipped. Boleys and the "real" names are upward of $10k (some of them, very very upward).
                    Max
                    http://joyofprecision.com/

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                    • #11
                      If anyone was wondering exactly how I manufactured the tapered rollers, I'll show you now. And the short answer is: I cheated.

                      I turned them with the tapered side toward the tailstock, then parted them off. To clean up the parted face (because I can never seem to get a nice finish from parting), I ended up making a tiny expanding arbor so I could reverse them for facing that side:

                      Here are the 3 pieces of the expanding arbor:


                      The expanding portion was only slit on one side. If I ever need to use this thing again, I'll make an expanding collar with several partial slits coming from opposing directions (the way ER collets are slit, for example). Here are the pieces assembled:


                      I used it with a collet, rather than making an entire WW shank... so any error introduced by the expanding collar would be in addition to the collet runout. Nevertheless, it seems to work just fine.
                      Max
                      http://joyofprecision.com/

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                      • #12
                        After thinking for a while about the remaining pieces that need to be made, I decided to make the locking "T" pin for the base, next. This pin will engage with the T slot base (or "shoe", or whatever you want to call it), and will have a very small range of movement via a lever at the bottom of the filing rest, to lock it into the T slot. I used mild steel for this - some scrap that a buddy of mine got for me a while ago. I don't know the alloy but it's not very nice to machine. Better than the hardware store stuff, at least.

                        Here's the turning in progress:


                        I switched between left hand and right hand tools to fully form the groove. Here is the T slot base being test fit onto the pin:


                        I told myself I wasn't going to worry too much about the finish on this part... I guess I lied to myself again because I ended up hitting it with some oil and fine abrasive paper backed withe a small slip of wood:


                        The decent finish on the rest of the part made the parted surface look all that much worse, so I filed off the machining marks on the parted surface with a coarse jeweler's file, followed by a pivot file (best thing since sliced bread, I would be lost without it!), followed by a couple grades of super fine abrasive paper and oil, backed by a glass sheet. Here's the nearly completed pin, sitting in the T slot... eventually it will need to be cross drilled but that will come later:
                        Max
                        http://joyofprecision.com/

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                        • #13
                          As a matter in interest to those looking at this thread that do watch repair/work, I have a watchmakers lathe and quite an assortment of watchmakers tools, notes etc. from my Dad when he was in watchmakers school in the late 1940's. I am not likely to use them myself and have mainly kept them for their sentiment value. However, perhaps it is time to consider allowing them to a new home where they would be put to better use than just taking up space. If there is any interest I could put together a list of what's here and go from there.

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                          • #14
                            i like your work and your blog a lot

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                            • #15
                              Originally posted by Robg View Post
                              As a matter in interest to those looking at this thread that do watch repair/work, I have a watchmakers lathe and quite an assortment of watchmakers tools, notes etc. from my Dad when he was in watchmakers school in the late 1940's. I am not likely to use them myself and have mainly kept them for their sentiment value. However, perhaps it is time to consider allowing them to a new home where they would be put to better use than just taking up space. If there is any interest I could put together a list of what's here and go from there.
                              Watchmaking tools are pretty popular these days, people are getting really good money for genuinely good lathes that are tooled up. I don't know how many posts I've seen on craigslist, with people looking for watchmakers lathes and tools. They seem to sell well on e-bay, as long as you have a lot of positive feedback as a seller. Here in the US we have local chapters of the NAWCC that meet regularly, and hold "marts" where members buy/sell/trade... not sure if there's anything of that sort up your way, though.

                              Originally posted by Elninio View Post
                              i like your work and your blog a lot
                              Thanks Elninio! Do you have a tumblr account? I hope to have some more time this spring to make some progress on my actual watch repair projects. It'll be nice to start posting some pictures of watch work for a change!

                              -Max
                              Max
                              http://joyofprecision.com/

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