Due to the difficulty of finding replacement ring gears at a
reasonable price for the Mazda auto tx flex plate I suggest we use
the current flex plate and merely tig weld the damper to it. Your
current starter is sure to still fit and work.

I was quoted ring gears $95 each from a company in NZ with $95
shipping by boat. No telling how long that would take.

Mark Steitle brought up the issue of room for a thrust bearing
between Tracy's spline flange (brown in the 3D) and the PSRU adapter
plate. Simple solution. Reverse it.

That gives more than enough room for a thrust bearing.

Here are the 3D's.

Some of the 2nd gen current flex plates have large holes near the
center that weaken them. The solution is tig weld in a plug. The 3rd
gen did away with the holes.

I just bought a 13B auto tyranny flex plate on ebay for $12. Shipping
and handling was $30 :)

Lots on ebay for $50.

Paul Lamar

Just a thought, the ring gear can be easily cut from an existing
flex plate, welded to new one. easier than cutting many plugs and
welding them into the old plate. C. Smith

That would add about $150 to the cost as there is labor involved
cutting off the ring gear and making and entirely new flex plate. If
that is OK for everybody I will do it that way. The plugs would be NC
laser cut out of 4130 scrap.


My guess on the cost right now is $250 +- $50

Paul Lamar




Paul,

I have a ring gear that I separated from a cracked flex plate.  Let me know
if you want me to send it.

FWIW, these are fairly easy to remove,  There are a few short welds
that must be ground off and then you can tap them a little at a time, going
around the perimeter and get them apart.  A little heat and the ring would
probably fall off on its own.

My thoughts regarding the welding... we need to be very careful so as to
not to cause warpage.  I believe they should first be tacked multiple spots
around the circumference, then welded a short distance, move across to the
other side, and weld a short distance, then move back and repeat the
process, keeping the heat even.  And they still may warp. A small amount of
runout will cause the flex plate to eventually crack.  Been there, done
that.

Mark S.

Ye4s I want it.

Three options in order of cost.
A Weld to existing flex plates
B Find a new ring gear and buy it. Weld a new flex plate.
C Remove ring gear for flex plates and weld up new flex plate.

Vote :)

Paul Lamar


Let's see...
Option "A" would be the heaviest, but would probably have least warpage
from welding

Option "B" - Not necessary (for me) as I have a ring gear.  Also, new ring
gears are difficult to find.  But could be combined with option "C" for
those of us that already have a ring gear.

Option C - This option allows for the 20b folks to get the thicker .125"
flex plate (less likely to crack).  Would ring gear spacing be the same?
This design would probably be the most compact, allowing more space for
thrust bearings, and easier to pre-flight.

I like Option "C", with option "A" as my second choice.

Mark

Bill Jeppson came up with a good idea. Bolt it on as I have a rotary
table to drill the holes and check the run out.

Paul Lamar

Why can't we remove the ring gears from our flex plates our selves then send them on? again, this is real simple to do. I don't see the need to pay someone to grind out 4 or 5 welds.
On the warpage issue in re-welding, use pre-heat, just as you do with 4130 tubing.
C. Smith


The Rotary Engine News Letter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
You Tube http://tinyurl.com/beqqxas
Copyright 1998-2013 All world wide rights reserved.