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Recent content by ogesII

  1. O

    New to me Pratt & Whitney 12 x 30 model B

    Mine has almost a 2:1 pulley reduction off the motor and a 900 rpm name plate on the belt housing. I just tested it with the tach and got 1780 at the motor and 926 at the top pulley. It's interesting how many different speed plates we are seeing. You'd think with my S/N being relatively low, I...
  2. O

    New to me Pratt & Whitney 12 x 30 model B

    I'm adding my serial number plate to the thread for anyone who's curious. Sent from my SM-G920V using Tapatalk
  3. O

    1925? Pratt & Whitney 12x30 Model B

    So those pictures are of the reverse clutch, right? The pin looks very clean compared to mine -- that should work fine. But the dog does look pretty warn. What's strange is it looks like there are two pins on the gear? Sent from my SM-G920V using Tapatalk
  4. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Ok, the issue with the binding isn't the opposite pin hitting the helix. It could be a clutch linkage adjustment issue but I haven't seen any adjustment yet. The binding only happens occasionally when engaging the forward feed and the pin doesn't fully engage with the dog. When this happens I...
  5. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Well shes all back together and working great! Getting the headstock back on and everything reassembled only took 3 hours. Now that I've done it once, this could easily be a one day job if everything goes smoothly and you have the replacement parts on hand. I didn't clean up the dog with a...
  6. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    I'll see how the surfaces mate up tomorrow after I press the pins in and resemble the shaft. I'm not too worried about damaging it because I only shift the clutch at 0 rpm. There are cone clutches in the carriage that I use for engaging while things are spinning. Sent from my SM-G920V using...
  7. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    The material is fairly hard so I was thinking I couldn't mill it. I only have HSS end mills. I guess I could try cutting it to see what happens. Sent from my SM-G920V using Tapatalk
  8. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Well all the parts have been washed in WD40 and are ready for reassembly tomorrow. I made two pins to replace the reverse pin also since I'm in there. They are both tempering in the oven right now. After further inspection, the keyway on the feedshaft is what caused all the trouble. The shaft...
  9. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    I don't know much about EDM but since the lathe was produced in the mid '40s I'm guessing it was completely a manually cutting process. Just looking at the piece and the helix makes me wish I could have been there to watch one being made.
  10. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Here is a picture of the rough surface on the shaft. I'm guessing this is what caused the issue. To the finger tip it feels mostly smooth but the finger nail can feel the abrasions.
  11. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    So using the rotary table to mill a new pin was a failed experiment. I can hold a diameter for 0.75" depth of cut but I lose 0.005 in the last quarter of an inch. The pin needs to be an inch long. I'm using a 5/8 4-flute HSS end mill to do the cutting. I thought the larger diameter would hold a...
  12. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Yea, I miked the shaft and the bore on the dog clutch and there is 0.0025 clearance which seems perfect considering it is keyed. The bearing wasn't actually the problem, instead it was the dog clutch which is behind the bearing that was causing the hang up. But in looking at the shaft, there are...
  13. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    I got it apart! The slide hammer was the trick but it still took a ton of pounding. Here is my slide hammer setup with the aluminum collar. Thanks Paolo_MD for the idea. Somebody had been in there before and did a more extensive repair moving the pin 180* on the gear. Here you can see...
  14. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Your repair looks exactly like what I have in mind -- if I ever get this bearing off
  15. O

    Single Tooth Clutch repair on Pratt Whitney 12 x 30 model B

    Actually I see now that the clutch disc I was pulling on is up against a shoulder so it must be assembled from the other end of the shaft. I guess there was no concern of me pulling it off then. From now on though, I'll be pulling on the clamping collar I made to make sure I don't damage that...
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