Page 6 of 6 FirstFirst 123456
Results 76 to 89 of 89
  1. #76
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    4,919

    Default

    Hi Neevo,

    My mill is a Chinese copy of an Optimum BF20L, the one with an extra long table and MT3 spindle.

    I was going to put a picture here, but it seem that its no longer in my pictures !!!

    Need help with new mill perchase-12-09-2019-007-jpg
    Best Regards:
    Baron J.

  2. #77
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default Try and repair or learn to live with it?

    What with lockdown Iím slowly running out of jobs in the garage, at least until I have more parts arrive for my Electronic Leadscrew build. So I set about making a scraper for the mill when I finally get around to scraping it in.

    I started with 3mm x 20mm steel. This works well with the exception of 1 part. Mainly because itís slightly curved across the width which gives it a bit extra strength but at the same time being flexible.

    Cut the pieces on the bandsaw:



    I had mistakenly bought a file handle for a file system that uses a locking handle. So the centre was a big hole. Not a worry, I popped some pine in the lathe and trimmed it down:



    Hereís the plan:




    Drilled a hole in the pine plug and hammered it all home without an issue. I also cut a step in the end of the scraper blade to accept some carbide:



    So on paper it looks good, but there is 1 part I need to redo. The carbide holder is too thin and bends when tightened down firm, so whilst the concept works. I need some thicker stock to make this part from. But that should be a relatively quick job:



    I used Stefans video here as the inspiration.

    https://youtu.be/QJXqHpSh3SE

  3. #78
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    No time like the present to fix the issue. Scrapped the old scraper holder and cut up some 10mm plate instead.



    A dramatic difference in rigidity!



    Mounted:



    Iím trying to figure out a way of using the large carbide insert I was given but may have to resort to buying one of those Sandvik scraper blades.

  4. #79
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    1,754

    Default

    Looking good.
    In my limited scraping experience - the Sandvik inserts just work, so unless your large insert is very similar Iíd say just buy a Sandvik one.
    Little bit hard to tell from the photos but to me it looks like your clamp may need to move downwards a bit, as youíll only be clamping the back third of the carbide.

    Steve

  5. #80
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    Yeah I think youíre right about the inserts. On the hunt for one.

  6. #81
    Join Date
    Mar 2014
    Location
    South of Adelaide
    Posts
    892

    Default

    I have seen this mob advertise the sandvik inserts on facebook

    https://www.facebook.com/PMKEP/

    Not sure what the go is now getting sandvik stuff here in Aus, they have shut their local office, not a big enough market apparently.

  7. #82
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    In preparation for doing some scraping Iíve added to my micrometer collection:



    Have a 0-1Ē and 1-2Ē Mitutoyo already so pleased to add a 2-3Ē, I really like the feel of them and their locking mechanism. The Starret is my first and took a fair bit of cleaning and taking apart to make it move freely but is now working perfectly. Not as nice as the Mitutoyos but still a nice quality feel. Doesnít have carbide anvils either.

    The 2-3Ē was required as Iím going to test out scraping on my lathe first. The dovetails are much smaller and will all fit on my little surface plate. Iím not planning on scraping the sliding surfaces much but aim to get the dovetails parallel, as mine are about 5 thousandths out:



    I need to grab some gauge pins but did the measurements with a couple of drills for a rough measurement.

  8. #83
    Join Date
    Mar 2011
    Location
    Adelaide
    Posts
    876

    Default

    Last time I needed two gauge pins, I just put a grinder through two 5mm drills that were blunt and cleaned the cut end up in the lathe. Rough enough for mining

    I like the scraper, that finished up rather nicely

  9. #84
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    Good idea. Can only find carbide gauge pins and theyíre $25 each. Will hack up a drill instead.

    Thanks on the scraper, I surprised myself too. Iím definitely getting more capable with machining the more I do it.

  10. #85
    Join Date
    Jul 2010
    Location
    Melbourne
    Posts
    8,795

    Default

    Quote Originally Posted by neevo View Post
    Iím not planning on scraping the sliding surfaces much but aim to get the dovetails parallel, as mine are about 5 thousandths out
    I'm not 100% sure how well that is going to work out.
    Do you have an idea how far out the flat ways are?

  11. #86
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    No idea on the sliding surfaces but Iíll measure them. Mostly just trying to remove the wear in the middle of the travel so I can consistently tighten the gibs. Same problem on my lathe and mill.

    I would assume though if the middle is worn on the dovetails then it would also have a corresponding dip in the centre of the sliding surfaces too?

  12. #87
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    55
    Posts
    1,754

    Default

    Other useful sources of pins for measuring uses are the shanks of endmills and the elements from parallel or needle roller bearings.

    Steve

  13. #88
    Join Date
    Jul 2010
    Location
    Melbourne
    Posts
    8,795

    Default

    Quote Originally Posted by neevo View Post
    I would assume though if the middle is worn on the dovetails then it would also have a corresponding dip in the centre of the sliding surfaces too?
    Without doing the maths.
    If the flat way isn't flat what does that do to your "across dowels" measurements?

    If we assume the flat ways are some sort of curve and you manage to get the dovetails flat and parallel.
    Won't that mean the cross-slide is trying to move in a straight line and a curve at the same time?
    Maybe things are close enough that is wont matter...

    Don't get me wrong, I don't always aim for perfection, often an improvement is good enough or at least "good enough for now". I just try to avoid doing something that will need redoing. But hey, if the flat ways are pretty close, what are they chances you'll put enough wear on them to ever need rescraping?

    Don't forget you need to keep the dovetail square to the ways(or almost lol)

  14. #89
    Join Date
    Sep 2009
    Location
    Sydney
    Posts
    502

    Default

    Iíll get the flats on the surface plate and see how far they are out. Might as well try and do it right from the beginning.

Page 6 of 6 FirstFirst 123456

Similar Threads

  1. What did you learn today?
    By Stustoys in forum METALWORK GENERAL
    Replies: 897
    Last Post: 9th Sep 2021, 08:31 AM
  2. The things you can learn when you try
    By Michael G in forum METALWORK GENERAL
    Replies: 16
    Last Post: 28th Feb 2016, 09:52 PM
  3. which tafe course to learn?
    By ftssjk in forum WELDING
    Replies: 27
    Last Post: 2nd Jan 2012, 10:41 PM
  4. Where can i learn 6g tig welding??
    By Jullin in forum WELDING
    Replies: 12
    Last Post: 5th Apr 2008, 11:53 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •