I can produce to your design if you need a source...Mark
----- Original Message -----
From: "Peter Vucinic" <vucinic@b140.aone.net.au>
To: "Tony Drews" <tony@tonydrews.com>; "FOT" <fot@autox.team.net>
Sent: Monday, July 05, 2004 1:57 AM
Subject: Re: Pump Shafts
> Gentlemen,
> Just updating on my oil pump shaft "fix" as listed below. I manufactured
the
> oil pump shaft as described and it was a complete success, using the
methods
> described. As we all know, the pump shafts supplied with current
replacement
> rotor kits are extremely poor in manufacture and are 'soft'. Virtually
mild
> steel. The first rotor kit that I fitted saw the pump shaft worn 0.010"
> within 2000 miles.
>
> In manufacturing my replacement rotor shaft I encountered the following
> manufacturing issues: -
> 1. The case hardened material made the machining of the tang slot
difficult.
> 2. The retaining pin/or locking fastener between the shaft and rotor was
> impossible to drill due to the case hardening of the shaft. I had to
firstly
> have a pilot hole spark eroded into the rod and then finish the hole by
> drilling. Very carefully!
>
> What I learnt: -
> 1. It would be far better to start with un-hardened material to
manufacture
> the shaft(s) and then have it hardened. What I made up on by utilising an
> already hardened shaft material, I lost in extending the machining time
due
> to the hardness of the material.
>
> I also manufactured a rocker shaft utilising the same material. It turned
> out splendidly. But the guys that had to spark erode all the rocker oil
feed
> holes
> said they weren't going to do another one for me in that way. Nearly drove
> them crazy!
>
> Regards
> Peter Vucinic
> TR-4
>
>
> > From Peter Vucinic in Aug 2003:
> >
> > Many thanks to all those that contributed to my TR4 Oil pump shaft
> problem.
> > Much good information and ideas were bandied about. So, to this end I
have
> > decided on having my own pump shafts manufactured as follows: -
> >
> > 1. Staring with 1/2" linear bearing shaft material. Readily available
'off
> the
> > shelf', hardened, ground precision rod. Case hardened to a depth of
about
> > 1-to-1.5 mm. The material is difficult to machine. But it can be done.
> > 2. Have the distributor shaft drive tang slot machined with a radius in
> the
> > bottom. This should be able to be accomplished using a ball nose milling
> > cutter.
> > 3. Use Greg Solow's idea of drilling and taping the pump shaft and pump
> > rotor.
> > 4. I am also looking at having the oil pimp body machined to take a
bronze
> > bush, at the rotor end.
> >
> > I have ordered the material(s) and I should have the finished product in
a
> > week or so. I will advise of the end result for those of you that are
> > interested.
> > Kind Regards
> > Peter Vucinic
> > WORKS-4
> > TR-4
> >
> > From Kas:
> >
> > That shaft material sounds very much like what we call "drill rod".
Cheap
> > and available at most steel servers. Available in many diameters,.
> >
> > Reply from Peter:
> >
> > Kas,
> > The material I am using is definitely not along the same lines as drill
> rod.
> > Linear rod is a precision ground, hardened bar used in such applications
> as
> > material handling/packaging equipment, where linear motion ball bearing
> > units are required.
> >
> > I am getting the specification sheet for this material, but haven't seen
> it
> > as yet. Typical mechanical properties for this material will be similar
to
> > the below: -
> > Hardened & ground - inch dimensions. Steel: Ck60 Surface hardness: 62
> > Tensile strength: 550-750 N/mm
> >
> > Kind Regards
> > Peter Vucinic
> > WORKS-4
> > TR-4
> >
> >
> >
> > At 10:20 PM 7/4/2004, Bill Babcock wrote:
> > >Seems like I remember a thread about better pump shafts. This part is
> > >obviously flawed. The stress in those sharp corners must be huge.
> Likewise
> > >the drive slot. Does anyone make an improved part with radiused edges?
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