On Monday 13 October 2014 08:01:35 andy pugh did opine And Gene did reply: > On 13 October 2014 12:50, Dave Caroline <dave.thearchiv...@gmail.com> wrote: > > I looked at the face of the slope and think it was done :- > > endmill the path along arrow > > http://www.collection.archivist.info/archive/mirror/03-620-Locknut,%2 > > 0Magneto,lv-gec.jpg > > My impression is that they are a true spiral, but it is hard to say: > http://www.geutskens.eu/neracar/6_foot_starter_assy.htm
I get the impression the ramps were cut with a straight end mill long axis so the cutting on the face was done on the side of the mill, while the rotary table was advanced in step. Note the groove across the face at 3 of the 4 90 degree aspects. It may have started as a casting so the face wasn't dead flat, not that it would count. But I also would have expected to see evidence of a small end mill cleaning up the push faces of the ramps, and I don't. Perhaps wear is hiding that. I looked around on that site, at some of the other pix. I know a bit about 2+hp per CID 2 strokes, and that one is wasting 50% of its power with those hugely wide rings. They are both a huge contributor to the heat from their friction, but also represent an un-realistically low rpm limit else they chatter, and break well before the 4000 feet per minute limit normally associated with broken piston rings. The thin steel rings can and have done 6 or 7 thousand feet a minute without breakage. You would be amazed at the increased zip it had if that bucket had its rings removed, and the locator pins too, and the groove hel-iarced closed, then remachined for a 1/32" thick steel ring, but reinstall the pins after centering the lower ring groove on the pin, but I'd place the top ring at the top of the present groove and relocate the anti spin pin to the top of the old groove. The anti-spin pin is to keep the ring from ever having an end, which would project out into the port, move across the port and get caught and broken by the edge of the port. Cleaning up the face of the deflector on the piston will help the high revs, but that design is generally all done by 7000 revs. I did manage to keep a 13 cid water cooled twin running at 8000 but it took every trick in the book. As it was a rotary intake, it took 2000 to get it started, but running on booze, by 4000 some 6" wide 12" diameter slicks were leaving black marks on the pavement behind me. Any idea how much piston to bore clearance it has now? Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Meet PCI DSS 3.0 Compliance Requirements with EventLog Analyzer Achieve PCI DSS 3.0 Compliant Status with Out-of-the-box PCI DSS Reports Are you Audit-Ready for PCI DSS 3.0 Compliance? Download White paper Comply to PCI DSS 3.0 Requirement 10 and 11.5 with EventLog Analyzer http://p.sf.net/sfu/Zoho _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
