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  • Several Regions have held meetups already, but others are being planned or are evaluating the interest. The Calgary Area Meetup is set for Saturday July 12th at 10am. The signup thread is here! Arbutus has also explored interest in a Fraser Valley meetup but it seems members either missed his thread or had other plans. Let him know if you are interested in a meetup later in the year by posting here! Slowpoke is trying to pull together an Ottawa area meetup later this summer. No date has been selected yet, so let him know if you are interested here! We are not aware of any other meetups being planned this year. If you are interested in doing something in your area, let everyone know and make it happen! Meetups are a great way to make new machining friends and get hands on help in your area. Don’t be shy, sign up and come, or plan your own meetup!

Search results

  1. RobinHood

    4140 crankshaft modifications - propeller hub build

    I turned some 4140 yesterday. 4340 should behave similarly. TNMG (I think it’s a 432), 570 to 770 rpm, 0.050” DoC, 0.008 to 0.010 “/rev. The lathe has to work a bit, but nothing that’s going to hurt or break anything. The large OD is 3.5”, the snout is 1.25”. (Yes, the boss of my part is...
  2. RobinHood

    4140 crankshaft modifications - propeller hub build

    No, I would not weld it. This is a critical part. I’ll get you a new piece of the exact same tool steel when I get home. PM me and we’ll set up the details.
  3. RobinHood

    Tool Post Grinder

    I would start with a known manufacturer of grinding wheels. Here is a link to Norton mounted stones (for example). https://www.nortonabrasives.com/en-us/searchproducts?f%5B0%5D=product_type%3A5591 If you expand the search, they give you applications, properties, specs, etc. That is common...
  4. RobinHood

    Tool Test Bar

    It’s all good. That’s what makes this Forum interesting.
  5. RobinHood

    Tool Test Bar

    Since we’ve veered off topic anyway… Pratt is not responsible for the interior of any airplane, not even anything beyond the basic engine and the components that make it run. It’s the manufactures in conjunction with the airlines who decide on the crappy interiors you speak of. It’s all about...
  6. RobinHood

    Anti-foam agent for oil ?

    As @PeterT states: complicated. I believe in your case with the small drill, the point where the oil exits acts like a “homogenizer”: it literally tears the oil molecules apart and in the presence of air, the solution reforms with air molecules trapped in it (the foamy, milky appearance). You...
  7. RobinHood

    Tool Test Bar

    I can’t remember if I did a write-up of the test. It was for another member (maybe @YYCHM ?) who had purchased one. We ran some generic test on my A level surface plate using high quality measuring tools. The bar was surprisingly well made (I think it was one from India).
  8. RobinHood

    Tool Test Bar

    Perhaps your work holding can be changed to clamping directly onto the mill table using one of the T-slots as an alignment guide? You’d be surprised how accurate a well set-up mill table can be and it solves your support issue at the same time. You can even “leap-frog” strap clamps without the...
  9. RobinHood

    Oxy fuel brazing brass

    I wondering if you need to preheat (in a BBQ for example) the part? It almost sounds like your part is sinking too much of the heat away.
  10. RobinHood

    4140 crankshaft modifications - propeller hub build

    I’d give it a try during the roughing phase. Also try a faster feed rate. I usually go to the point where the chips just turn from straw to blue (straw when they are airborne, [light] blue once they have landed). The lathe will let you know if it is still happy. 4000 series steels like...
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