Jump to content
Lunchy

Subaru Brat servo

Recommended Posts

The manual to the kit, right?  Or is there a manual that comes with the motor?

 

Thanks for you help?

 

Share this post


Link to post
Share on other sites

Hello everyone - 

I am about to start building the Brat... just looked at the instructions and saw something that I was a bit concerned about, being a newbie and all,  so figured I would reach out.

I see it gives a measurement between the pinion gear and the motor when tightening the grub screw... (See image below).   I'm sure everyone has their own way of doing things, but is there any good methods out there for measuring this to make sure you get it exactly right, if needed? 

image.png.aeea3ab6d9b3a952d99418d8def69b04.png

 

Thanks again all!

Share this post


Link to post
Share on other sites

The dimensions given in the instructions are generally drawn to size.

I tend to cut a piece of card, from a servo box or something like that about a centimetre wide, then cut the end squarely to the 16.5mm. Checking it with a ruler.

With one end of the card sitting on the motor face with the paper gasket in place (parallel to the shaft), loosely tighten the grub screw when the end of the pinion is flush with other end of the card you’ve cut. Spin the motor a couple of times and double check before fully tightening the grub screw.

You can also hold the motor in place on the gearbox without the cover plate on to see where the pinion is sitting on the spur gear.

Hope that makes sense mate.  

  • Like 1

Share this post


Link to post
Share on other sites

Hey guys -  Any thoughts on what is the best paint to use to paint the letters on the tires for the Brat?

 

thanks!

Share this post


Link to post
Share on other sites

I used an automotive tyre pen for my Buggy Champ, Brat, Wild One and Sand Scorcher shelf wheels.

The paint only lasted for about 3 runs on the Brat. It does look good when it’s fresh. If your going to be running your car a lot it’s probably not worth doing. Most people will have 2 sets of wheels, one nicely lettered for the shelf and a runner set.

I’ve heard of people using Tamiya PS paints for tyre lettering too. Spray some into the lid an apply with a toothpick or something. I’d tried it once but took ages to do.

8AD19BC4-A69E-4DF5-9B48-88615D596D1A.jpg

Share this post


Link to post
Share on other sites

Nice looking RC.

 

I ran into an issue today with the brat where part MR13 is missing.  Any ideas where I can get one?  

IMG-6707.jpg

Share this post


Link to post
Share on other sites

hey everyone.  

 

Couple of questions for you regarding the Brat that I am building...

1.   When building the gear box does the Bearing Lager really just sit on the bevel gear?  Seems like there would be some attachment or something.  the manual kind of shows that it just sits on it.  I attached a pic of the manual... IMG-6711.jpg.

2.   I thought when I had the gear box built the spur gear would spin the differential gear if I spun it.  So if I were to spin the spur gear the differential would also spin.  Mine does not spin.  Is that how it should be?  I attached a pic.. IMG-6709.jpg

 

A newbie to some of this stuff... but you guys have always been very helpful so I figured I should reach out.

 

THANKS!

IMG-6711.jpg

IMG-6709.jpg

Share this post


Link to post
Share on other sites

Sorry... another one for you.  What is the ring used for when connecting the drive gear to the spur gear... then Says to take off.  

41728459-369A-4166-BFEA-DB6B75B8EAB7.jpeg

Share this post


Link to post
Share on other sites

Hey @Lunchy, with regard to your Lager bearing query, (Larger printed as Lager 🍺 in the manual!!) have you put the metal 1150 bearing in the white plastic cup as in stage 8?

image.md.jpg

Can’t really tell from the photo. It seem odd that it doesn’t spin?

Try putting the drive cups in the Diff and spinning with your fingers to see if it’s working.

 

And the MR1 spring stays in place on the Spur Gear. They say it’s removable with tweezers if you wish to change to a different size Spur later with its respective Pinion gear.

There are 3 supplied gear options, 52 tooth Spur goes with 16 tooth pinion ( Torque, slowest top speed )

50 tooth Spur goes with the 18 tooth pinion ( Standard, medium ) 

49 tooth Spur goes with the 19 tooth pinion ( High Speed )

But all options will use the one MD3 part.

 

Share this post


Link to post
Share on other sites
11 hours ago, Lunchy said:

Sorry... another one for you.  What is the ring used for when connecting the drive gear to the spur gear... then Says to take off.  

41728459-369A-4166-BFEA-DB6B75B8EAB7.jpeg

The MR1 ring holds the MD13 gear in place, once it has been inserted through the PGx gear. It holds the gears together and prevents it coming loose and fouling the other gears.

Removing the ring allows you to remove the MD13 and use another PGx gear.

Terry

 

Share this post


Link to post
Share on other sites
12 hours ago, Lunchy said:

hey everyone.  

 

Couple of questions for you regarding the Brat that I am building...

1.   When building the gear box does the Bearing Lager really just sit on the bevel gear?  Seems like there would be some attachment or something.  the manual kind of shows that it just sits on it.  I attached a pic of the manual... IMG-6711.jpg.

2.   I thought when I had the gear box built the spur gear would spin the differential gear if I spun it.  So if I were to spin the spur gear the differential would also spin.  Mine does not spin.  Is that how it should be?  I attached a pic.. IMG-6709.jpg

 

A newbie to some of this stuff... but you guys have always been very helpful so I figured I should reach out.

 

THANKS!

 

 

1. Yes the bevel sits adjacent to the bearing. No big deal. Once the drive cups are inserted, the bevel is designed to work with the bearing and not against it, ie it’s supposed to be that way. 
 

2.  The best way to check good gear movement is to insert the drive cups, then turn each one the same direction - one cup in each hand. This will cause the diff gear to spin the spur gear. If you spin one cup and let the other spin freely, the differential will actuate and spin the free drive cup in opposite direction of the one you are spinning, and the spur gear will NOT rotate.  If you lock one cup while you spin the other, the differential will actuate, and the spur will rotate.

In all 3 cases, the movement should be nice and smooth and take minimal effort.  How much effort depends on the grease you use.

The ORV tranny is easy to get “backwards”.  If the tests above aren’t working, try rebuilding your tranny.  I’ve done dozens of rebuilds and I always manage to get something upside down or backwards...

Terry

  • Like 1

Share this post


Link to post
Share on other sites

Frog Jumper - When you say MD13... do you mean MD3?  If so, MD3 went right in nice and tight... didn't seem like you would need the ring.  I guess I might be missing something.

 

As far as the drive cups go... what are they? 

I actually didn't go past step 9.  Maybe that's why it seems lose and sloppy?  

 

Thanks again!

Share this post


Link to post
Share on other sites
1 hour ago, Lunchy said:

Frog Jumper - When you say MD13... do you mean MD3?  If so, MD3 went right in nice and tight... didn't seem like you would need the ring.  I guess I might be missing something.

 

As far as the drive cups go... what are they? 

I actually didn't go past step 9.  Maybe that's why it seems lose and sloppy?  

 

Thanks again!

Yes MD3. Sorry.  Use the ring.  It might be fine now but if the gear comes loose, it will be catastrophic.

And the drive cups are the things that stick out of either side of the tranny and drive the drive shafts to turn the axles.

Terry

 

Share this post


Link to post
Share on other sites
1 hour ago, Lunchy said:

At what point do you take the ring off?

When you change the gear and insert another gear. By switching gears, you can switch between the (3) different gear ratios offered with the Frog/Brat. 

Share this post


Link to post
Share on other sites

Finally found time to look at the ReRe Brat manual...

The drive cups are parts MD15 and MD16.  See step #12 and #13.

Terry

  • Like 1

Share this post


Link to post
Share on other sites

Got it.  Thanks.  Love learning new stuff about this hobby.

 

Another for you.  I got some Fast Eddie Bearings for it.  I assume I just use these bearings when it calls for a plastic one... am I correct in saying that?

 

Also - When using the fats Eddie bearings, do I add grease like it calls for when using the plastic one?

 

Thanks!

 

 

Share this post


Link to post
Share on other sites
2 hours ago, Lunchy said:

Got it.  Thanks.  Love learning new stuff about this hobby.

 

Another for you.  I got some Fast Eddie Bearings for it.  I assume I just use these bearings when it calls for a plastic one... am I correct in saying that?

 

Also - When using the fats Eddie bearings, do I add grease like it calls for when using the plastic one?

 

Thanks!

 

 

The bearings will go in place if any of the white plastic bushings.

I lube my tranny bearings but leave my wheel bearings dry. Grease can work as an adhesive and will turn into liquid sandpaper if it gets dirt sand or grit in it. In a closed system like a tranny, there is little chance of contamination so grease is ok. On wheels, the bearings live in a dirty environment. I will occasionally rinse them out with water and then hit them with some WD40.  Usually after our annual trip to the beach...

Share this post


Link to post
Share on other sites

I decided to go with the sport tuned motor over the stock.  I noticed the colors of the wires are different.  The stock motor has a green and yellow wire, while the sport tuned has a red and black wire.  

On the lunch box I believe the yellow wire went to the yellow wire on the esc and the green wire went to the blue wire on the ESC.  

What should I do for the sport tuned motor... what color wires should connect to the ESC?  

There is a pic that I attached

 

Thanks

 

 

Comparison of Motors.jpg

Share this post


Link to post
Share on other sites

Plug the Red into Yellow, and the Black into the Blue 👍🏻
 

(Orange from the ESC is not needed for Brushed motor)

Share this post


Link to post
Share on other sites

I have everything going well with the build but I do have one concern.  When I spin the drive shaft or where the wheels will attach the gears do not seem smooth. so for example, if I spin them both at the same time in the same directions it is very smooth.  If I spin one side and the other side spins in the other direction it feels rough and kind of "Grindy"... would that be normal?  Hope this make sense.

 

Thanks!

 

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...