Turbo Optima mid SE

[GoMachV]

Yeah the pressure plates are the diff rings. Looks complete to me

[radioactivity]

The 2nd question...

It seems as if there were 2 different of methods to "clamp" the diff balls in the diff.
One method using a pressure plate and another with diff rings.
Are any diff rings compatible with the conventional (later?) style diffs?
Inside diameter slightly over 8mm, outside diameter 18.3mm.

Chuck

[keithrc]

On the subject of SE ball diffs, are we limited to Kyosho replacements of the diff balls and drive washers or are there generic parts that will fit and work just as well?


Keith

[radioactivity]

Keith
I measured the diff balls at slightly more than 3mm, so I am guessing 3mm is the magic number.
The thrust bearing balls measure right at 1.5mm.

The diff rings, which are what I am curious about, may be the same/similar to ZX5/ZX6 diff rings.
I sent off a couple messages to sellers asking about inner and outer diameters on Kyosho WBD4 Lazer ZX5ZX6 rings.
The image on Kyosho's site makes me think they may be close.
On Kyosho's site I took the size of the ring on my screen and compared it to the text on the header card. Then I compared that with the same style header card I have.
Rough approximation but it seems very close.

pressureplate.1.JPG (25.92 KiB) Viewed 1300 times

pressureplate.1.JPG (25.92 KiB) Viewed 1300 times

If no answer from sellers I will probably just go ahead and order some unless anyone else here has an answer.
My NIP rings measure an inside diameter slightly over 8mm, outside diameter 18.3mm.

Chuck

[keithrc]

Thanks Chuck , very handy info there. I've got an incomplete SE here with a few upgrades and very tight diffs, feels like they're in bad need of a refresh. Apart from the diff parts, I think I have most parts needed to get it back in one piece except for the stabilizers.


Keith.

[radioactivity]

Keith
You're quite welcome.

I did just get a reply from Amain tech "The outer diameter of these rings measures 18.5mm while the inner diameter measures 8.1mm."
This is close enough to get me to order a pair of these pressure plates and compare with my originals. I will update when I get them.

I will also want to add sway bars. My arms are new style so they are a bit different.
Good luck on the refresh, will you have any build pics?

Chuck

[XLR8]

Hi Chuck. I've been trying to catchup with progress and I have a really dumb question - sorry about that.

So, you have a new diff assembly for the front that uses "presser plates" but you've also found replacement diff rings and I'm assuming these are for your rear diff?
Not sure which is late vs early so I'll avoid referring to them that way. I recall that both of my SE's use plates rather than rings and although they are clean, they are really notchy. It seems that the plate's turned surface is nowhere as smooth as the surface of rings so I think I would prefer to have rings.
I was just wondering if there is a way to fit (or bond) the rings to the plates or if doing so would increase the overall width making the assembly too wide to fit the case.

Again, I may be totally lost so ...

[radioactivity]

Hi Doug

Nope, there are no dumb questions only dumb answers. And I've given my fair share of dumb answers.
And you're pretty much spot on, not lost.
I've been a little vague because I wasn't really sure of what direction I was going with the gear/ball diff decision.

Story is that I got a large grab bag of RC parts and low and behold there were front and rear ball diffs for a TOMSE in the mix, what are the odds of that?

I was not necessarily intending to go ball diff but I guess they are more original/preferred, not that the rest of the car is original. Seems as if I can't leave well enough alone anyways.
I had just gotten the SG25 set up for gear diffs and was headed in that direction. Already had all the new internals for the front and rear gear diffs.
Now I will probably go with the ball diffs because it seems I've got all the pieces.

To try to answer your question.
The rings for the rear diff are appx. .67mm and the spacers for the front ( if they were eliminated) are appx. .2mm.
Though I haven't tried to assemble either diff, it would seem as though adding rings to the presser plates would be too wide. Unless the presser plates were machined for the additional width of the rings.

Another part of the build, the front diff, has had me kind of stuck for a while.
The front gear box case ( 1/2 of an OT-84 ) has threads that were stripped. I thought a dab of CA would help but I did not like the results. Too far gone.
And I can't seem to get my hands on a front diff box either. At least not yet.

The only other option I can think of is to try 3mm helicoils. And who knew there is such a thing as STI tap, not me.

Chuck

[XLR8]

Ah, okay, got it Chuck. Thanks for the summary.

So, I've never had to use thread inserts but I read that they work great. Now that I think about it, as many old motorcycles as I have in pieces over the years, it's odd that I haven't needed to repair some pulled threads but so far none. Anyway, if the thread insert solution goes awry for any reason, I could send you a set of printed cases.
This may take some time however as they will need to come from the printers. Perhaps you could use them as placeholders until something better comes along.

By the way (and for what it's worth), I have two sets NIB complete ball diffs for the Ultima and they also use plates. In fact, I don't have a single Kyosho ball diff that uses rings. It would be interesting to learn the history - which came first and why did they change them.

[keithrc]

Keith
You're quite welcome.

I did just get a reply from Amain tech "The outer diameter of these rings measures 18.5mm while the inner diameter measures 8.1mm."
This is close enough to get me to order a pair of these pressure plates and compare with my originals. I will update when I get them.

I will also want to add sway bars. My arms are new style so they are a bit different.
Good luck on the refresh, will you have any build pics?

Chuck

Thanks again Chuck. Sorry no pics as yet, just wanted to see if there was a more affordable option. Reading the last few posts has me curious about my diffs, might have to do some disassembly to see if they have the rings or not.

[radioactivity]

I got the Kyosho WBD4 pressure plate rings in the mail today.
OD matches exactly. Thickness matches exactly. ID is slightly ( .02mm) larger.
I would say that they will work just like the original ball diff rings.
The ring on the right is OEM.

Chuck

[EvolutionRevolution]

AFAIK, Kyosho has a habit of reusing many parts in later cars. For the electric car diffs, the Optima gear diffs evolved into the Lazer gear diffs and then the Tour Force gear diffs, and the same goes for the ball diffs (not too remarkable, because the TF-1 is basically a shortened, narrowed Optima Mid...).

[radioactivity]

Update...

I trimmed the body and wing finally.
The wing shows a method I have been using to get those pesky corners started without a lot of effort.
Not the final corner but a good start.
The paper punch is also pretty handy for getting a nice round end to the slots cut for shock towers etc.

Chuck

[radioactivity]

I had also been trying to decide for a color for the body when I remembered something.

In the middle of page 4 of this thread XLR8 posted an amazing rendering of a white TOMSE.
So I stole his image and opened it in MS Paint. Thanks Doug!!

From there I just started flooding the white areas with different colors.
This made it so easy to visualize against the decals, it was like cheating. Thanks again Doug!!!
And I found the color I really liked.

Did I say Thanks Doug???

Chuck

[radioactivity]

So then on to recreating the color.

Though I have 40 or more colors of paint nothing came close.
So mixing drops then small batches of paint was next. After getting an idea of the correct mix I went on to spray.
Spraying samples on scrap lexan with different thickness of paint and amount of backing paint.

I settled on approximately

1st coat
75% Createx Fluorescent Yellow
10% Createx Flourescent Green
10% Createx Base
5% Parma Fascolor Faschange Green (for a slight pearlescent addition)

Backing coat
90% Createx Iridescent Green
10% Createx Base

2nd Backing coat
100% Createx White

Still need to paint the body....


Chuck