Re: Looking to buy a handwheel for apron for Heavy 10
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I have had exactly the same problem on my steam loco renovation. One or two joints in the valve gear are held together by a collar and tapered pin rather than a washer and plain spit pin. 2 collars went missing over the 19 years the job has been ongoing, but the chassis is now finished awaiting the boiler, promised back from the contractor at the end of September.
This is what I did after turning a new collar:
1. Place tapererd pin in hole in spindle and, by eye, scribe a line across the end of the spindle as close to aligning with it as you can.
2. Measure distance of hole centre from shoulder.
3. Drill a hole a the same size as the small end of the tapered hole in the spindle into the collar at the right distance from the face that abuts the shoulder.
4. Fit the collar to the spindle, then put your small drill in the hole as far as it will go, and wiggle the collar around till it is central, then continue the scribed line across the collar.
5. Centre pop the second side of the collar and drill slightly larger than the second side, but not so big the taper pin enters to full depth.
6. Get busy with a round needle file till the taper pin enters decently and finally remove the absolute minimum metal with the taper reamer. You can make your own taper reamer from silver steel (USA "drill rod"?) by turning on the taper, flatting to exacly half the diameter and hardening.
Caution: Metric standard taper is the nice round 1 in 50, Imperial is the nice round 1/4" per foot which is 1 in 48. And yes, it does matter if torque transmission or vibration are present.
On Tuesday, 9 July 2019, 00:55:13 BST, Jim_B <jim@...> wrote:
Yes John a mil could be substituted for the lathe, but you are still stuck finding the correct and\gle and offset in order to drill a matching hole in the hand wheel collar so the taper pin fits both the shaft and the collar without drilling another hole in the shaft.
Of course drilling a second hole is always an option.
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