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Tamiya mini cooper

Old 06-29-2015, 10:02 AM
  #24181  
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Or you could use a vacuum pump. Had mine of years so think that Tamiya makes it. Not sure though
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Old 06-29-2015, 10:36 AM
  #24182  
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Originally Posted by eR1c
I saw the photo before I read the post, ..I was like what the heck is that? some kind of beefy outdrive that is connected to the wheel??

Love your shock holder, i'll have to remember that for next time. I usually pour the oil in then look around my table for some nicely sized crevice to hold my shock ...or lean it up against something. Not as elegant a solution as you've come up with.
HAHAHA!!

Originally Posted by Granpa
Or you could use a vacuum pump. Had mine of years so think that Tamiya makes it. Not sure though
Yes, I should get one. I only rebuild dampers occasionally so been doing it this very ghetto way. Fill, move shaft up/down, and let it sit for 5min or so.
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Old 06-29-2015, 11:29 AM
  #24183  
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I have a couple of M03's for sale.

http://www.rctech.net/forum/r-c-item...m03s-sale.html
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Old 06-29-2015, 02:00 PM
  #24184  
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Yes, I should get one. I only rebuild dampers occasionally so been doing it this very ghetto way. Fill, move shaft up/down, and let it sit for 5min or so.[/QUOTE]

I'm quoting you, but this really is not meant for you. This is working for you so-----------.

This is meant for the guy who doesn't have a vacuum pump, but wants to build his shocks properly. If you want to blow oil past your seals, just leave air in your shocks. Air expands as it gets warmer and shock movement builds up heat in the shock---------walla, leaky shock. May not be noticeable, but if you've ever taken a shock apart and the oil level is less than full, it was leaking. Another way to check is to hold the shock close to your ear and move the shock shaft-----you'll be able to hear it and a full shock is totally silent. If you've lost a lot of oil-----maybe more than 4or5 drops you'll be able to feel that as you move the shock shaft.

Like in all things, this is just my opinion. 5 min is not long enough to let all the air bleed out. Especially if you moved the shock shaft up and down without doing so slowly and slightly tilting the shock. If you move it quickly, you'll have caused the air to foam in the shock oil and you'll have to let the shock rest for at least an 30 min. or so. The heavier the oil, the longer.

Okay, so how do you do it. Pour a small amount of oil in and move the shaft and piston so that you don't trap an air bubble under the piston. then fill the rest of the shock with oil. Pour the oil in like you would if you were pouring a beer and did not want to create a head. If you foamed the oil removing the air under the piston, that oil will be lighter so it will come to the top as you pour the rest of the oil. Obviously, using this technique the shock shaft will remain fully extended.

The only sure way to get air out is to use a vacuum pump. However, having said all that, a lot of good racers don't use a vacuum pump. I'm just anal about shocks. What's funny though is that I've had cars handle great even tho the bottom shock collar came off and oil was all gone.
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Old 06-29-2015, 02:13 PM
  #24185  
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Yeah, I do fill the oil in steps. I do agree I should get a vacuum pump regardless.

I do a drop of damper oil before shaft entry into the housing to lube the o-ring and coat the bottom of the inside of the housing, then another drop of oil on the thread and side the shaft in half way, fill to the top allowing the oil to drip below the piston.

Then fill some more, and more, and then move the piston all the way down and top off. Very slowly move the piston up and down a few times preventing foam, and let it sit for 5min or so. The entire process takes like 12-15min.

Usually by then most of the air is out, I can't see any more bubbles bursting at the top.
This is using the Tamiya clear oil, if I use the blue oil I need to leave it open for like 25-30min.
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Old 06-29-2015, 02:55 PM
  #24186  
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Thanks for the oil filling tips guys.

Does the position the piston is in when you put the cap on effect the shocks performance? i.e should it be at full extension or pushed all the way in?
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Old 06-29-2015, 03:17 PM
  #24187  
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How about after they've been filled and the bubbles are out from under the piston, you set them aside overnight? I tend to start rebuilding them late in the evening, then cap them the next day.
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Old 06-29-2015, 03:29 PM
  #24188  
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shocks? What shocks? ...we run "dampers" in our minis, right?

..good info, Granpa makes a great argument for a vacuum pump. But at least i'll pay more attention next time i fill my dampers.
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Old 06-29-2015, 03:43 PM
  #24189  
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Originally Posted by sakadachi
Made minor progress today. I realized this kit uses no servo saver.

I think I'm going to run Kimbrough just in case.

Ghetto damper holder to get the bubbles out.
I've been shopping around for a mini chassis and can't find any of the old tech racing CFRP conversions of the M05. Your car looks like its a treat of a mini. what is it and where did you purchase it?
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Old 06-29-2015, 04:29 PM
  #24190  
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Originally Posted by filippimini
Thanks for the oil filling tips guys.

Does the position the piston is in when you put the cap on effect the shocks performance? i.e should it be at full extension or pushed all the way in?
I usually have it extended all the way down because the oil crowns at the top when I have the piston all the way up, which basically spills out when I screw the cap. I fill it just enough that the inner gasket floats off the damper housing. Then the excess is minimal.

Originally Posted by monkeyracing
How about after they've been filled and the bubbles are out from under the piston, you set them aside overnight? I tend to start rebuilding them late in the evening, then cap them the next day.
Okay, you win!

Originally Posted by byteme909
I've been shopping around for a mini chassis and can't find any of the old tech racing CFRP conversions of the M05. Your car looks like its a treat of a mini. what is it and where did you purchase it?
That is my new TOP Racing SabreFD Mini. I bought it from a guy on ebay, but if you're in the USA, TQRacing carries it, so do many stores in Asia, and you can also buy directly from https://www.topracingusa.com/

Monkeyracing has a Xevo which actually sparked my interest in these Tamiya M-chassis geared other brand cars. There's also a 4WD version of the SabreMini if you're interested. I looked at the 4WD and it looked very similar to my Tamiya M-Four, so decided to try the FWD chassis. I'm really liking the quality of this kit. Zero play with the suspension arms, very smooth, fit and finish is top notch.
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Old 06-29-2015, 04:42 PM
  #24191  
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Originally Posted by eR1c
shocks? What shocks? ...we run "dampers" in our minis, right?

..good info, Granpa makes a great argument for a vacuum pump. But at least i'll pay more attention next time i fill my dampers.
Yep, there's no substitute for good tools!

I see there are different length pumps. I am assuming for our cars we can use the regular length pump, but I have trucks that run much longer damper housings that I also want to use on.

This one appears to be overkill though in length?
Is there like a Long one but not "Super" long?

http://www.tqrcracing.com/shop/produ....asp?p_id=5161
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Old 06-29-2015, 05:08 PM
  #24192  
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Originally Posted by filippimini
Thanks for the oil filling tips guys.

Does the position the piston is in when you put the cap on effect the shocks performance? i.e should it be at full extension or pushed all the way in?
I didn't touch on this cause it's a totally different subject. This is pretty much what happens----Not 100% correct, but, hay, it's close enough. Here's what happens----let's say you have the shock fully extended and the oil filled to the top of the shock body. If you push the shock shaft up, oil will spill over the edge. As the shock shaft moves up, it will displace the oil and cause it to overflow.

Now this is why we have the bladder. If we put the bladder on a shock with the shock fully extended, as you push the shock shaft up, since you cannot compress a liquid,as the liquid or oil is displaced, the bladder deflects. The more the the shock shaft moves, the more oil is displaced and the more the bladder deflects. This is why, if the shock is not fully up, the shock shaft will come back out, because the bladder will want to return to it's original shape. If it doesn't come back out at all, that's a zero rebound shock. 2mm a 2mm rebound shock. And so on.
The amount the shock shaft extends from the bottom of the shock body, When th e top ring is cinched down goes a long way in determining how much rebound your shock will have. It's important to make the shocks the same from side to side, not so much front to rear. I imagine you could alter handling by making the front and rear shocks a different rebound, but I don't drive good enough to have seen a measurable difference.

This brings us to another subject. It is impossible to build a zero rebound shock with a Tamiya TRF type shock if your components like the bladder are in good shape. When you put the cap on, you will trap air between it and the bladder. As you tighten the top ring, the bladder compresses and so does the trapped air which causes it to distort the bladder and force the shock shaft out. You can get around this by drilling a small #60 sized air bleed hole in the plastic cap. The TCS tech guy did not like this, so plug the hole up after the shock is assembled. That's a totally different subject about anatomy and orifices.

I hope this explanation did not get too basic, but it wasn't intended for the pros.

Last edited by Granpa; 06-29-2015 at 05:24 PM.
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Old 06-29-2015, 05:31 PM
  #24193  
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Bladder, that's what I was I trying to say!!

I brainfarted and couldn't remember the term..
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Old 06-29-2015, 06:02 PM
  #24194  
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One more tip. When using the oil dispenser, I wait until the air inside the dispenser rise and pop inside and at the tip of the dispenser before flowing oil into the damper.

That air can get inside your damper and it makes it nearly impossible to rid the bubble.
Worst is when you move the piston and cause foaming.

Need to start over then.
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Old 06-29-2015, 09:43 PM
  #24195  
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Finished building the chassis. I didn't have any Lipo's charged at the time so popped in my old NiCd.
I am running the Kimbrough servo saver as the kit only came with a servo horn (no servo saver included).
I set the ride height dead even front to rear to start, D60 Super Grip Radials front with firm inserts and
rear with soft inserts.




Took it out for its test drive without the body. Here are my impressions:

1) THE GOOD: Very easy to drive, no throttle on/off twitching, a tad on the tail happy side
during off throttle. Will dial-in the suspension and alignment once I figure out how to mount
the Rover Mini body on it.

2) THE I COULD LIVE WITHOUT: Gearbox is LOUD! Yes, I did re-check the mesh on the pinion.
It is as loud (if not louder) than my M03 and Tamiya off-road trucks.
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