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  1. J

    Workholding -- itty bitty polycarbonate cones

    I Googled chicklet and I'm still none the wiser. Can you provide a drawing of what you're making?
  2. J

    Lets Talk 6X4 Bandsaws !

    It looks good to me Timo.
  3. J

    Shrink Fit

    ouch.
  4. J

    Let's talk milling machines

    I recommend these guys: conon motor A bit more expensive than eBay, but they offer good support and the manual that comes with the VFD is reasonably easy to understand. My PD is mid-80s Taiwanese. I was able to dispense with the intermediate pulley. I replaced it with a belt tensioner. Sorry...
  5. J

    Let's talk milling machines

    Hello Baltic and welcome to the forum. The VFD I fitted to my pedestal drill has an adjustable PWM frequency so you can select a frequency that doesn't annoy you. Perhaps yours allows this too?
  6. J

    Shrink Fit

    Yes, you're right. This video explains: https://www.khanacademy.org/science/in-in-class11th-physics/in-in-thermal-properties-of-matter/in-in-thermal-expansion-in-solids/v/thermal-expansion-of-ring-class-11-india-physics-khan-academy
  7. J

    Shrink Fit

    No worries. I made some edits while you were posting. I reckon a test is a very good idea. The Q sounds like the perfect place to do the heating.
  8. J

    Shrink Fit

    Hi, while researching many websites on shrink fits (in steel) I came across the following rule of thumb: allow 0.025mm (1 thou) per 25mm of diameter for a shrink fit I heated the outer piece to 200C in my kitchen oven and cooled the inner piece in the freezer. I still needed to give the inner...
  9. J

    Etcher/marker

    I'm not one to sell tools (my kids can have that pleasure when I'm gone), but I've read that engraved tools attract lower sale prices. Some say up to 50% lower. So probably not a good idea to engrave expensive tools. Perhaps engraving the size doesn't devalue the tool as much as engraving your...
  10. J

    Etcher/marker

    I didn't know such a beast existed.
  11. J

    Etcher/marker

    Gordon, Unless you have superhuman vision, you're going to need a loupe to read the engraving on a ⅛ diameter tool. In which case why not just reach for the digital callipers and measure the diameter of the tool? If the tool I want to use isn't in its original packaging with the size marked on...
  12. J

    A new attempt at making piston rings

    I seriously doubt that.
  13. J

    A new attempt at making piston rings

    Fair enough Brian. I haven’t tried lapping a big piston. which confirms my thinking that the fit of the piston isn’t critical for a piston with rings. There are thousands of engines being mass produced every day without lapped pistons.
  14. J

    A new attempt at making piston rings

    Brian, a VFD will solve that problem. When the speed is very slow, the torque is low enough that you can stop the lathe with your hands. You would have absolutely no trouble stopping my lathe with your T handle.
  15. J

    A new attempt at making piston rings

    And doesn't that prove that the fit of the piston in the cylinder isn't terribly critical for a piston with rings? Because if it was, a cold aluminium piston wouldn't develop enough compression to start the engine. True. And my clapped out old lawnmower would be impossible to start. And yet it...
  16. J

    1" Bore x 1" Stroke Vertical i.c. Engine

    This is how the F1 mechanics solve that problem: "Due to the very tight bearing and piston-to-bore clearances on an F1 engine, the engine cannot be started from cold and must be brought up to the recommended start up temperature in order to avoid damage to the moving parts. The recommended...
  17. J

    Lathe slide wobble

    Being Chinese I reckon it's more likely they decided they could save money by not adding them. 🙂 What's the gib in the picture from?
  18. J

    Lathe slide wobble

    Perhaps not, but if you refer to post #4 the OP said his gib originally didn't have pockets, so he added them. So he already knows the experiment you suggested won't help.
  19. J

    South Bend lathe

    I have a Hercus 260 which is a metric Southbend 9 clone built under licence in Australia. I replaced the wicks in my saddle. It was straightforward if you take care. The saddle is actually quite a complicated piece of gear. Use the manual- don't try and wing it. I know yours is a 13 which is...
  20. J

    Lathe slide wobble

    Just to clarify here, the saddle rides on the bed/ways. The cross-slide rides on the saddle. If you can shake the saddle by hand I don't think the gib screws are the issue (despite what loosening the screws may have led you to think). There's something else going on. My lathe has a plate on...
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