Re: Vespa + HPI Mini Rotor

Graham Motzing /
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i dunno if you figured out the taper cutting thing or not yet but this is how my toolmaker buddy taught me to do it

#1- put the crankshaft in the lathe in a 4-jaw so you can true that fucker up to the .0001 in terms of runout, put a dial indicator in the actual tool holder of the lathe, like, clamp it in where you would put the cutter, measure the runout at the taper itself, because even the best crank ever won't be that perfecto. when i do them, i will use a sacrificial crank and just bash it into place with a hammer. never done a vespa but with puch and tomos i clamp to the opposite side bearing race.

#2- now you loosen up the cross slide and get the angle close. snug it down a lil' bit and run the dial indicator across the taper. at this point i use a tiny hammer or usually the wrnch from the tool holder to just tap it back and forth while running the cross slide in and out across the taper. obviously you're going to go back and forth and you want the indicator to stay at '0' +/- .0002 or so. Then you rotate the crank like 90 degrees a couple times and repeat. Usually the tapers have some surface roughness so you'll never get it perfect but you get a good feel pretty quick for getting that cross slide dialed in on the the fuckin nuts. once the crossslide is tracking the taper perfect, tighten it down, check again, and remove the crank

#3- put the rotor in the 4-jaw, true that fucker up on the inner surface- this way you keep the factory balance. Take the dial indicator out and put a boring bar in the tool holder. cut the taper to whatever size you need. I usually figure what the smallest diameter will be and use a pin-gauge to guess and check but if you have a DRO or some fancy shit you can probably just get it right on that way. the actual bore diameter is probably only +/- .005 because you can shim your variator out to whatever you want by putting a shim between the flywheel and vari.

this is how i've done it for putting different-taper stators on different cranks.

This single post is part of a larger thread. Start from the top or view this post in context.
Subject Written By Posted
  Vespa + HPI Mini RotorTopic by: Max (ツ) Max (ツ) 05/11/16 09:36PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/11/16 10:28PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 05/11/16 11:00PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/12/16 07:09AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 05/12/16 09:55AM
  Re: Vespa + HPI Mini RotorRe: Mike Boyd Mike Boyd 05/11/16 11:19PM
  Re: Vespa + HPI Mini RotorRe: ***VANILLA BLUNDER*** ***VANILLA BLUNDER*** 05/12/16 09:18AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/12/16 11:22AM
  Re: Vespa + HPI Mini RotorRe: Dave Steele Dave Steele 05/12/16 03:43PM
  Re: Vespa + HPI Mini RotorRe: «tyler » «tyler » 05/12/16 09:09PM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 05/13/16 12:22PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/13/16 05:41PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/18/16 09:58AM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 05/12/16 09:32PM
  Re: Vespa + HPI Mini RotorRe: «tyler » «tyler » 05/12/16 09:51PM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 06/01/16 12:51PM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 07:19AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 09/30/18 02:51PM
  Re: Vespa + HPI Mini RotorRe: Dirty30 Dillon Dirty30 Dillon 10/02/18 10:50AM
  Re: Vespa + HPI Mini RotorRe: JBOT Admin JBOT Admin 06/01/16 01:04PM
  Re: Vespa + HPI Mini RotorRe: JBOT Admin JBOT Admin 06/01/16 01:16PM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 07/25/16 08:10AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 08:32AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 08:35AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 10:23AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 09/10/16 10:25AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 09/23/16 08:26PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 10/01/18 11:30PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/02/18 12:03AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 10/03/18 10:20AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/03/18 11:32AM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 12:58PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/08/18 01:19PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:31PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:44PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:57PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/08/18 03:08PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 03:45PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/31/19 05:49PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 03/31/19 07:18PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:26PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:28PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:31PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 04/03/19 10:43PM
  Re: Vespa + HPI Mini RotorRe: Dave Steele Dave Steele 04/04/19 11:30AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/04/19 11:37AM
  Re: Vespa + HPI Mini RotorRe: EH FCC of the QCB EH FCC of the QCB 04/04/19 06:27AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/04/19 07:26AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/04/19 01:58PM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/04/19 03:41PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/21/20 08:35AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/22/20 12:02PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/22/20 06:43PM
  Re: Vespa + HPI Mini RotorRe: ᴛᴇʀʀʏ ᴅᴇᴀɴ ᴛᴇʀʀʏ ᴅᴇᴀɴ 03/22/20 11:01PM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/01/20 08:40AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/01/20 09:05AM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/01/20 11:53AM
  Re: Vespa + HPI Mini RotorRe: Daniel '' Daniel '' 04/01/20 09:51PM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/02/20 09:34AM

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