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Re: Turbo Optima mid SE
Posted: Mon Jun 19, 2023 4:44 pm
by radioactivity
RichieRich wrote: ↑Mon Jun 19, 2023 4:11 pm
@ radioactivity If I'm reading your post correctly, a small adjustment, using the shim between the floating piston and the head of the shock shaft, makes the rebound much better?
This is the result of my "finger dyno".
I took 2 shocks with no springs, one with shim and one without.
Both shocks with 30w oil and set piston to head of the shock shaft gap the same.
At this point both shocks had the same o-rings, the old orange rings.
Mixed them up and tried to see if there was a difference. Kinda/sorta "blind".
One shock felt less damped on the rebound. Took it apart and it was the shock with the shim.
Not exactly scientific but to me, convincing.
I did all 4 shocks with shims after that. To me a very noticeable difference.
It may not be a perfect solution but maybe a step in the right direction.
If you should try it please let me know if it's only me!
Chuck
Re: Turbo Optima mid SE
Posted: Tue Jun 20, 2023 3:11 am
by RichieRich
Ok, yeah. I totally understand now. Any testing on these shocks is welcome. I have set of medium length platinum shocks that aren't being used right now. I may do some testing like you've done.
Re: Turbo Optima mid SE
Posted: Thu Jul 27, 2023 11:59 am
by radioactivity
Again not being able to leave well enough alone...
I've watched several YouTube videos by Barbatos Rex. Primarily videos about chrome paint and clear coating chrome paint.
I also saw that Dadio had experimented with Alclad paints.
The upshot is the AlcladII chrome and Alclad Aqua Gloss is very near the best chrome paint solution available.
I was fairly satisfied with the results on my wheels originally but wanted to try a better finish on them.
So I completely stripped them.
Primed with base coat and a very lightly applied coat of chrome.
Then a light coat of Alclad Aqua Gloss and I got what I believe is a much better result.
Trying to get a good pic of chrome is not real easy. Kind of like taking a picture of a mirror.
The effect of a light coat of the chrome almost gives a black chrome finish. I love it.
Before
After
Before
After
Chuck
PS
Not to beat a dead horse but adhesion to nylon wheels is not a problem, particularly with this paint.
Either flame treating, sand blasting or light sanding will get the job done.
This is not to say it's durable enough to take a beating on a track. Shelf duty is fine.
Re: Turbo Optima mid SE
Posted: Tue Aug 01, 2023 5:03 pm
by radioactivity
ESC #3
My Novak1 was DOA and the Novak T4 really did not fit very good.
The orange anodize on the Spektrum A5070 servo needed something to balance the look.
Also the amp draw on the servo is pretty high so I got a Spektrum Firm ESC, BEC has 7.4V and 4amps available for the servo.
Tucks in the chassis about as far as I can get it.
New servo mount also moved the servo in a little farther
New axles with a small spring in the outdrive
Mounted the refreshed wheels with tires
Chuck
Re: Turbo Optima mid SE
Posted: Fri Aug 04, 2023 1:51 pm
by XLR8
The car is looking great Chuck.
Something that should have been obvious all along has just struck me -- you're actually planning to RUN this beautiful car!!!
Please do your fans a favor and keep it away from the gravel??

Re: Turbo Optima mid SE
Posted: Mon Aug 07, 2023 11:25 pm
by RichieRich
Yeah, it looks fantastic. The wheels really came out nice.
Re: Turbo Optima mid SE
Posted: Mon Aug 28, 2023 1:48 pm
by Coelacanth
radioactivity wrote: ↑Tue Aug 01, 2023 5:03 pm
My Novak1 was DOA and the Novak T4 really did not fit very good.
The orange anodize on the Spektrum A5070 servo needed something to balance the look.
Also the amp draw on the servo is pretty high so I got a Spektrum Firm ESC, BEC has 7.4V and 4amps available for the servo.
Tucks in the chassis about as far as I can get it.
optima82.JPG
Chuck, as your Optima Mid chassis is quite similar to mine, I thought I'd share how I mounted my ESC, a Leopard Toro 60A unit, sideways. I'm not sure how wide your ESC is, but this can help you tuck it in completely under the top chassis plate.

Maybe this might work for you.

Re: Turbo Optima mid SE
Posted: Mon Aug 28, 2023 10:10 pm
by radioactivity
Coelacanth
I have tried with my Novak 1 and the Novak T4 about every config I could think of trying.
Don't think I didn't look at all your cars closely for inspiration.
OptiMutt has something my car does not, that little bit of extra space where I have to contend with the lower belt cover.
But I may steal one more idea from you, possibly a name of sorts.
Cyanamid
What I really want to help complete the car is an OT85 idler. I have one designed but just can't convince my self to print one.
In my hunt for a gear I found that the Robinson and the Pargu are both 32p not .8 mod. They are too small in diameter and noisy.
It "grinds my gears" to hear that gear box howl.
A 28t .8mod derlin idler is my "Holy Grail".
Chuck
Re: Turbo Optima mid SE
Posted: Mon Mar 18, 2024 4:44 pm
by radioactivity
For the handful of you that have Platinum shocks....
Several months ago, while working on my shocks, I had tried new white P4 orings. They turned out to have been too tight and have too much friction.
The original orange Kyosho orings were somewhat leaky, and after reinstalling them they still tended to leak.
So I gave it one last try to stop the leak.

- Shock o-rings.2.jpg (35.97 KiB) Viewed 1690 times

- Shock o-rings.2.jpg (35.97 KiB) Viewed 1690 times
What I did was replace the orings that seal the shock body to the lower shock cap with slightly thicker Associated orings.
I found the original orings were in pretty bad shape.
Never had removed them and originally thought they probably OK.
They were not.
By replacing the old orings with the thicker orings there was not as much "squish" on the new white shock shaft orings.
Happy to say no leaks and very, very smooth shocks.
Chuck
Re: Turbo Optima mid SE
Posted: Mon Mar 18, 2024 4:58 pm
by coxbros1
radioactivity wrote: ↑Mon Mar 18, 2024 4:44 pm
For the handful of you that have Platinum shocks....
Several months ago, while working on my shocks, I had tried new white P4 orings. They turned out to have been too tight and have too much friction.
The original orange Kyosho orings were somewhat leaky, and after reinstalling them they still tended to leak.
So I gave it one last try to stop the leak.
Shock o-rings.2.jpg
What I did was replace the orings that seal the shock body to the lower shock cap with slightly thicker Associated orings.
I found the original orings were in pretty bad shape.
Never had removed them and originally thought they probably OK.
They were not.
By replacing the old orings with the thicker orings there was not as much "squish" on the new white shock shaft orings.
Happy to say no leaks and very, very smooth shocks.
DSC08514.JPG
Associated vs Kyosho orings.1.jpg
Chuck
Nice update!...Platinums are key for any vintage build...keeping them going is cool
Re: Turbo Optima mid SE
Posted: Mon May 06, 2024 11:49 pm
by radioactivity
This is getting picky but...
The gear I was going to use to replace the Kyosho OT-86 counter gear was a Robinson RRP-3750 for Optima Mid.
The Robinson is a much better gear than the poor excuse for a gear that Kyosho made but the Robinson is 32p. Why 32p, why not the correct .8mod???
I found an M.I.P. MD-3 and after a couple emails discovered it is the correct .8 mod. Thank you Eustace!
And the M.I.P. is a really, really nice gear.
Before 32p = .8mod discussions, I can tell you these two counter gears do not play well together.
When held together and rotated they are notchy and don't mesh good.
Robinson left M.I.P. right
Next item in the mail will be my holy grail 27t .8mod 20degree P/A acetal ( derlin ) center gear from
https://rwracing.co.uk.
This will replace the OT-85 Pargu that is also 32p. The Pargu is pretty looking but not what I want.
Really can't hardly wait till the RWracing gear gets here.
This combination should yield the best trans I can build.

- Optima Mid-4 Acetal Idler Gear.JPG (15.05 KiB) Viewed 1588 times

- Optima Mid-4 Acetal Idler Gear.JPG (15.05 KiB) Viewed 1588 times
Chuck
Re: Turbo Optima mid SE
Posted: Fri May 24, 2024 1:35 pm
by radioactivity
The installation of the rwracing.co.uk acetal gear did not go as smoothly as possible.
But I believe it is partly due to my usage of the ball diff vs using a gear diff.
The rwracing gear is much wider than the Kyosho OT85 style gear. Approximately 9.1mm for the rwracing gear vs 7.7mm for the Kyosho and about 8mm for the pargu aluminum 32p OT-85 variant.
This extra width caused interference with both the gear diff and the OT-86 main gear pinion.
For the most part, trimming the rwracing gear width to 8.8mm tended to solve the interference problems.
Then shimming the bearings properly and adjusting the main gear shaft a little got the gear in place without any interference.
It is a very tight fit even with the ( now thinned ) gear. Clearances of approximately .004" to .010 side play all around.
Chuck
Re: Turbo Optima mid SE
Posted: Fri May 24, 2024 2:30 pm
by radioactivity
A portion of the interference at the ball differential was caused by the integral shoulder on the gear. Ball diff on right.
It is a little difficult to see in the pic but the 2 piece design of the gear diff, on the left of the pic, gave a little more clearance.
The diff cannot really be shifted side to side and spacing the full size ( 9.1mm ) idler to clear the ball diff caused the idler to contact the inside of the gear box.
That is why the rwracing idler gear needed to be thinned to 8.8mm.
Chuck
Re: Turbo Optima mid SE
Posted: Fri May 24, 2024 2:56 pm
by radioactivity
Now with all the clearance issues aside, on to the benefits.
15% wider contact area vs the Kyosho idler gear. More face contact = more strength.
The Kyosho idler gear, by all appearances, is quite soft and not very durable.
Conversely a Derlin/acetal/POM gear is beautiful to machine, very durable and a known high quality plastic for gear manufacturing.
The gear train is now back to all .8mod. The slightly larger OD of .8mod vs 32p has removed all unnecessary slop between the gears.
The gear train feels buttery smooth when rotated.
Really quiet when spinning.
Overall very happy with results, well worth the effort.
The final "breaking in" of the gears is accomplished with compressed air blown across the spur gear. Spin the heck out of it.
After 3-5 minutes of high speed break in I feel the case, out drives, etc to feel for any warm/hot areas that could potentially show binding or friction.
And the last spin revealed that the diff was a little too tight. Removed one thin shim and it now spins quite smooth and freely.
That blow gun is a favorite tool for breaking in gear boxes.
Chuck
Re: Turbo Optima mid SE
Posted: Sun Jul 28, 2024 3:44 pm
by radioactivity
Much like designing and having a center gear printed only to find a Derlin center gear already available for purchase, I recently designed and had Shapeways print spring perches for 12mm springs.
The rear springs that I have are the "Hard" ( gold finish ) version and they feel way more stiff than most other comparable springs.
I have been looking for the original "Medium" ( black finish ) version for a very long time.
The thought being 12mm springs to be more easily found than the rare and oddly sized springs for Kyosho Platinum shocks.
Yes some early Losi springs and some Duratrax springs can works but length and spring rates are pretty much a shot in the dark.
I think the 12mm spring perch adapters look really nice. 12mm on left original Kyosho on right.
I felt as though they were a really nice improvement over an earlier attempt at 12mm adapters.

- optima75.JPG (52.37 KiB) Viewed 1472 times

- optima75.JPG (52.37 KiB) Viewed 1472 times
All that being said I recently found the elusive Kyosho AD-9 Springs, the correct springs for the rear of a TOMSE.
Black springs "Medium" on left are the recent acquisition, gold springs on right are the incorrect "Firm" springs
So I now have an correct full set of black medium springs.
So..." Much like designing and having a center gear printed only to find a Derlin center gear already available for purchase, I recently designed and had Shapeways print spring perches for 12mm springs."
I have twice, and fairly recently found, if I go to the effort of finding a solution to an unobtainable part ( design, print and wait ) that part generally falls in my lap shortly after I complete my solution.
Chuck