Easy Sherline Tool Post Grinder

Discussion in 'Horological Tools' started by Joseph Bautsch, Mar 13, 2019.

  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  1. Joseph Bautsch

    Joseph Bautsch Registered User
    NAWCC Member

    Dec 9, 2006
    1,112
    122
    63
    Male
    Retired
    Atlanta, GA
    Country Flag:
    Region Flag:
    The attached photo shows an easy to make, less than half a day, tool post grinder for the Sherline. A two and a half inch length piece of 3/8" square cold rolled steel, faced off and with a 45 degree edge is strapped to the body of an pneumatic pencil grinder. The straps are worm screw 5/16" clamps on each end of the bar. The grinder is a Astro Pneumatic Tool Co. device. It turns 58,000 rpm. Thats way more rpm than needed for any project. The max psi is 90, but runs best at 60 psi. The silver band on the back of the grinder is an off/on speed control. The grinder is for light weight grinding, shaping and polishing and takes the 1/8" diameter shaft attachments. . The grinder is set up in a Sherline adjustable tool block, for 3/8" cutting tools. With a protractor any angle can be set up on either side of the work or head on.

    0-9.jpeg
     
  2. Uhralt

    Uhralt Registered User
    NAWCC Member

    Sep 4, 2008
    3,651
    341
    83
    Country Flag:
    Region Flag:
    Looks good. How do you prevent the abrasive dust from grinding damaging the lathe? I managed to kill the front ball bearing of the headstock of my Sherline. Since then I avoid grinding on the lathe.

    Uhralt
     
  3. karlmansson

    karlmansson Registered User

    Apr 20, 2013
    2,498
    85
    48
    Doctor
    Linköping, Sweden
    Country Flag:
    Plastic bag that the work pokes through tends to do the trick. Probably easier with a collet than with a chuck though.
     
  4. Joseph Bautsch

    Joseph Bautsch Registered User
    NAWCC Member

    Dec 9, 2006
    1,112
    122
    63
    Male
    Retired
    Atlanta, GA
    Country Flag:
    Region Flag:
    My understanding of the Sherline head bearings is that they are sealed. Grinding is a common work procedure in using any lathe and with sealed bearings, grinding dust should not have any affect on them. To find out Sherlines recomend procedure, the effect of grinding, I have sent a question to the engineering and technical people there for a response. I'll let you know what they say.
     
  5. MartinM

    MartinM Registered User

    Jun 24, 2011
    2,956
    79
    48
    Male
    Medical Insurance Systems Analyst
    El Dorado, CA
    Country Flag:
    Region Flag:
    I use an thin sheet aluminum shield on my mini lathe that surrounds the chuck and keeps the abrasive elements out of the intersection of the output shaft and the machine body. It is held in place by setting it on top of the machine and using the magnetic mount for a dial indicator.
     
  6. Joseph Bautsch

    Joseph Bautsch Registered User
    NAWCC Member

    Dec 9, 2006
    1,112
    122
    63
    Male
    Retired
    Atlanta, GA
    Country Flag:
    Region Flag:
    Here is the response from Sherline. Evidently there are more components of the machine that are subject to damage from fine grinding dust. Occasional grinding will have a minimal effect. But should not be an ongoing work process. Sherline also recommends using the toggle switch cover.

    "Joseph,
    Grinding dust is the absolute worst thing for any machine. We do not recommend grinding on our machines.
    The headstock bearings are lifetime sealed bearings. However, grinding dust will find its way into everything (including the speed control.
    If this is going to be something that you do once in a while, then the impact on the machine will be minimal.
    If you are turning your machine into a fulltime grinder, there will be premature wear on the bearings.
    I highly recommend buying the toggle switch dust cover p/n 3015 (https://www.sherline.com/product/3015-toggle-switch-dust-cover/ ) for the power switch on the speed control. If grinding dust gets into the switch, it will short it out."
    Have a great day,
    Karl"

    A good cleaning after each use will go a long way to extending the life of the lathe, but that is true after any use not just grinding.
     
    Uhralt likes this.
  7. Joseph Bautsch

    Joseph Bautsch Registered User
    NAWCC Member

    Dec 9, 2006
    1,112
    122
    63
    Male
    Retired
    Atlanta, GA
    Country Flag:
    Region Flag:
    Attached is a couple of photos showing how I made Jerry Kieffer's lantern pinion knurling tool. The knurls sold by Sherline are hardened HSS tool steel for cutting. The only way to get the shape needed for the lantern pinion knurling tool is to grind the shape. There is, and rightfully so, concern for the grinding dust getting into the machine head and controller. The solution is to use an upholstery vacuum tool held next to the work being done. That will pull most all the grinding dust into the vacuum. A small green stone is used for the 45 degree inside facing and a larger green stone was used to cut down the outside diameter to the size needed. Both the lathe and the stone should be turned at a slow rate of speed, with the stone cutting on the backside of the work. Even so grinding on the Sherline lathe is not recommended on a regiular basis.
    0-3.jpeg 0-1.jpeg
     
  8. Uhralt

    Uhralt Registered User
    NAWCC Member

    Sep 4, 2008
    3,651
    341
    83
    Country Flag:
    Region Flag:
    Joseph, thank you for following up with Sherline! My bearing was killed after only a few minutes of grinding. Maybe the dust cover wasn't working or they may have changed it after I got my lathe. Anyway, I will remain cautious and cover what I can if I need to grind on the lathe.

    Uhralt
     
  9. MARK A. BUTTERWORTH

    MARK A. BUTTERWORTH Registered User
    NAWCC Life Member

    Jul 4, 2009
    2,237
    66
    48
    Male
    Diistributor of movements and movement parts.
    Muscatine, Iowa 52761
    Country Flag:
    Region Flag:
    One might consider making a grinding machine by putting a Jacobs chuck or
    3 jaw chuck on an electric motor or even an electric drill. Then if it gets ruined it will be far less expensive to replace.
     
  10. MARK A. BUTTERWORTH

    MARK A. BUTTERWORTH Registered User
    NAWCC Life Member

    Jul 4, 2009
    2,237
    66
    48
    Male
    Diistributor of movements and movement parts.
    Muscatine, Iowa 52761
    Country Flag:
    Region Flag:
    Another thing to consider regardless how one does the grinding operation, is the damage the dust can do to one’s lungs. In some cases it maybe carcinogenic. Nose mask and eye protection could be helpful.
     
  11. D.th.munroe

    D.th.munroe Registered User

    Feb 15, 2018
    297
    79
    28
    Male
    Full time clock and watchmaker
    BC Canada
    Country Flag:
    Region Flag:
    I got a cheap old ww lathe for grinding and messy polishing with a shop vac dust collector, and the same style of grinding post as the OP, still have to use my cross slide and I do still clean it all regularly.
    This is a very important thing to always consider. If you care about your health.
    I also wear nitrile gloves if I'm touching stuff alot and for many other things.
    Dan
     
  12. wefalck

    wefalck Registered User

    Mar 29, 2011
    457
    20
    18
    Male
    Paris
    Country Flag:
    Wearing gloves when operating machines with rotating parts should be a no-no. It is very easy for a glove to get caught and then your finger will wind around the spindle too ... still have to find any dangerous stuff to touch in a watchmaker's workshop (apart from some plating chemistry and the likes).
     
  13. D.th.munroe

    D.th.munroe Registered User

    Feb 15, 2018
    297
    79
    28
    Male
    Full time clock and watchmaker
    BC Canada
    Country Flag:
    Region Flag:
    Well I was hoping that was obvious. I mean when its not running.
     
  14. Jerry Kieffer

    Jerry Kieffer Registered User
    NAWCC Member

    May 31, 2005
    2,436
    236
    63
    Male
    wisconsin
    Country Flag:
    Joseph
    I suspect you would receive the same response from every manufacturer with some being more appropriate than others. As an example, I would never grind on my Cowells Lathe with the cone bearings and cost should damage occur.

    However, in regard to Sherline, it is my opinion that they may not be considering one of the major advantages of their machines. The machines are highly effective and very reasonable in cost compared to other compatible machines. I use and abuse mine approximately 1200 hours a year on a daily basis and have done so for the last 35 years or so.
    While I do not grind on a daily basis, I probably grind on them as much as anyone. To purchase separate grinding equipment to do what I do on these machines, would cost several times the cost of the Sherline machines themselves. While I have never had a bearing issue from grinding dust, Had I had so, it would not of been a issue.

    I would have simply replaced the headstock bearings being only a tiny insignificant amount of separate grinding equipment and very simple to do as follows.

    (1) Remove (press out) the old bearings from the headstock and then the bearings from the spindle.

    (2) Freeze the new bearings and spindle.

    (3) Remove the bearings from the freezer and immediately drop into respective cavities of a room temp. headstock.

    (4) Once the bearings have reached room temp., remove the spindle from the freezer and immediately drop into the bearings. Adjust per Sherlines instructions.

    Jerry kieffer
     
  15. wefalck

    wefalck Registered User

    Mar 29, 2011
    457
    20
    18
    Male
    Paris
    Country Flag:
    For the last 150 years or so lathe manufacturers have been making and selling toolpost-grinders. For most of that periods grinders and headstocks had cone-bearings. So there must be some merit in them - ok, someone said, the lathe manufacturers did this to increase their lathe sales ;)

    There are some situations, when grinding a part in situ is warranted, as re-chucking it in another machine would mean loss of cocentricity. Also, you want to re-grind your lathe centres in the spindle to which they belong. All these are occasional operations, not production activities. So, with adequate protection, this is, as Jerry was pointing out, the only economic way.
     
  16. Uhralt

    Uhralt Registered User
    NAWCC Member

    Sep 4, 2008
    3,651
    341
    83
    Country Flag:
    Region Flag:
    If I had only known the freezing trick earlier! When I replaced the bearings I did everything at room temperature and had a very hard time pressing the new bearing and spindle back in. I was concerned that I might have damaged the new bearing in the process but luckily it survived my brutal force.

    Uhralt
     
  17. Jerry Kieffer

    Jerry Kieffer Registered User
    NAWCC Member

    May 31, 2005
    2,436
    236
    63
    Male
    wisconsin
    Country Flag:
    Wefaick
    Great point and far better explained than I.

    It should also be noted that cone bearings are easily cleaned if there is a concern. I should also mention, that if my Cowells lathe were my only Lathe of this size, I would not hesitate one second to grind on it even though I may take more precautions than with the inexpensive Sherline.

    Uhralt
    I should also have mentioned to always oil the Sherline headstock cavities and spindle when installing bearings.

    Jerry Kieffer
     
  18. Joseph Bautsch

    Joseph Bautsch Registered User
    NAWCC Member

    Dec 9, 2006
    1,112
    122
    63
    Male
    Retired
    Atlanta, GA
    Country Flag:
    Region Flag:
    This follow up adds a lot more accuracy and versatility to the grinding process using Sherlines Lathe Compound Slide #1270. (By the way even while Sherline frouns on grinding they do sell a Micro Grinder Tool Post Holder #8976). The slide mounts on the lathe cross slide table and can be set to to any angle to within .5 degree. The mounting bar is cold roll steel 1.5"x.5"x.25". Mill a groove down the center of one side. The two parallel lines generated will give the mounted handle a lot more stability and keep it from shifting up or down while grimding. Two end slots are cut, (.040" wide) to accommodate the clamps. Cut the slots so that there is more width than .25" to fit in the clamping slot of the slide. The compound slide has three different mounting positions, left, right and across the front. Using a powered flex cable handle and drive also allows the turning direction to be reversed. It should be noted that the handle center line is not on the lathe turning center line but that has no affect on the grinding process.
    1270_pic.jpg 0-1.jpeg 0-2.jpeg 0.jpeg IMG_1139.JPG IMG_1140.JPG IMG_1141.JPG
     

Share This Page