Any progress on the simple PSRU? I have a neighbor that is a
retired millwright, and he has a 12" metal lathe in his basement.
He has been building mini steam engines in his basement for a
while- a steam powered mini ferris wheel, locomotive, etc.
Last I remember you were discussing using the ceramic bearings-
and were trying to get them from China. If I can get an idea of
the internal parts and where to get them, I can try to make one.
Have we made any progress lately?
Kevin Alderman
It will be awhile. We had a ceramic bearing supplier picked out
but there was some evidence he was less than reliable. We are
attempting to finding another source.
Paul Lamar
I assume the heart is a Ford planetary, but where does the splined
shaft come from? Do we have to machine the splines on a shaft?
Kevin Alderman
It must be welded up from a manual transmission, one inch
diameter, input shaft or Ford auto tranny splined part. Tracy uses
the auto tranny part.
Paul Lamar
OK, I guess I need to go get a used E4OD and tear it apart and see
what's inside. Sounds like fun!
Kevin Alderman
No need. New parts are cheap.
http://www.makcotransmissionparts.com/
I have ordered from them and I think Tracy also buys from them.
Here is an outfit on the west coast.
http://www.slauson.com/
We are in the process of ordering the bearings in china now.
The smart thing to do is let us build one and see if it works
first :)
Paul Lamar
\--------------------------------------------------
You can order thin section steel bearings from mcmaster carr
but steel thin section bearings are limited rpm wise.
we are using the 4 inch size.
This is why we are trying to buy ceramic thin section bearings.
Cost is the reason for buying them in china.
Paul Lamar
I just noticed the NOTE:. The max RPM is with grease as a
lubricant. High RPM would heat the grease due to the internal
friction in the viscous material. How will lubricating with oil
affect the RPM rating?
Dale Davies
Perhaps a bit higher but no way is steel going to live long enough
with grease or oil.
Here is the specs on Shanghi Lilly thin section ceramic bearings.
The success of this design depends on the high rpm capability of ceramic
bearings.
Paul Lamar
Paul, I was looking at the attachments and it appears that the 4"
standard all stainless construction thin section bearing is rated
at 4800 RPM (grease) and 5700 RPM (oil). The propshaft would be
turning 7500 RPM/ 2,85 or 2631 RPM, well in range of a 5700 RPM
bearing. It would seem that using silicon nitride balls in the
bearing for an 8000 RPM rating would be overkill. I understand
that the input shaft might be turning 7500 RPM but with a much
smaller diameter where the speed ratings are much higher. It would
seem that a standard size bearing with C3 clearance would be
appropriate on the input shaft.
george grimes
The Shanghi Lilly are ceramic balls.
What manufacture was that? Most all steel thin section bearings
that size are limited to below 1000 rpm.
Paul Lamar
Paul, I was looking at the attachments on the 8:51 am posting. One
chart was 4800/5700 and the other chart ranged from 8500 to 15000
RPM for the same size. It would seem either type could be used.
george
Those RPM numbers are for the silicon nitride balls not steel
balls. The last attached jpg shows a steel ball bearing that comes close.
The penalty is a smaller shaft and a much larger housing.
The shaft strength goes up with cube or the fourth power of the diameter.
Paul Lamar
------------------------------------------------------------------------
This company in general does not post the RPM.
Paul Lamar
---------------------------------------------------------------------
This one might be worth a try to validate the concept as Milo has
suggested.
The cost makes it unattractive.
Paul Lamar
==========================================================================
Paul, will this do the job? Milo
Buy online VD040CP0 Thin Section Bearing 4"x5"x1/2" inch Open Slim
Ball Bearings
VXB Home Thin Section Bearings
VD040CP0 Thin Section Bearing 4"x5"x1/2" inch Open Slim Ball Bearings
Quantity in Basket: None
Part Number: Kit13153
Our Low Price: $179.00
Shipping Weight: 0.10 pounds
========================================================================
No I don't think so there is no RPM specified.
It would only last a few hours.
Paul
I spent weeks sorting the bearing issues out. Contacted all of my local
suppliers, and most of the 50 state online houses. Nearly all of
them did not return my query. I have been visiting bearing houses
for 30 years, this time they stumped me.
Plus, the size we need is actually 6821, not 6820. And, 4x5x 1/2 was
available for $500 each in silicon nitride with only 4 available nationwide.
We want this size:
105x130x13mm, this size is listed as 6821. You must specify silicon nitride
balls when you request a quote.
Anyone can buy the steel ball version of any of the above sizes for
about $20 each on ebay. But you cannot get the 6821 in this country,
especially with the ceramic balls.
We are the highest taxed nation in the world folks, that is why they
are only available in China. No investor would be dumb enough to
dump half million dollars into the newest bearing manufacturing
equipment only to watch ameropean or european governments stripe the
profit potential away.
I am currently tooled up to make the prototype. I don't have time
this next 4 months or so to continue the process.
Ed Carver
We can make minor changes in the size using sleeves. So if we can
find 100x125 in ceramic that is a more common size. 100 is 3.397
while 105 is 4.133.
I am tempted to spend the big bucks on this Amazon one just to try
a steel unit rated at 4400 RPM but only after Henry tries ordering
ceramic bearings from his Chinese supplier.
Paul Lamar
OOPS; 100/25.4 = 3.937"
Dale Davies
Right! thanks dale for catching that.
Paul Lamar
--
The Rotary Engine News Letter. Powered by Linux.
ACRE NL web site.
http://www.rotaryeng.net
You Tube key word PaulLamar2
Copyright 1998-2012 All world wide rights reserved.