These are best for deburring http://www.amain.com/product_info.ph...all-End-Reamer

Wow. Tool snobbery much? I mean I know we're all tool snobs and looking for the next gizmo to display in our toolboxes, but geez.

Dude, get a good, nice, new 2mm drillbit (I prefer those with a quick fit hex driver - I have a driver, plus it can be used by hand if need be) and drill from inside, then cut the burrs on the outside with a scalpel/hobby knife new blade around the base of the drill after it punched through. Withdraw the drill and voila! The perfect burr free hole. Any 2mm hex driver will go through that hole when it's lined up with the ball hex.

The drillbit itself can be used as a reamer after drilling the hole by pushing/pulling it through the hole without spinning. The very sharp edges of its cutting spiral do a great job, but it might drag some swarf inside the cup, so be careful.

That's it, job done with 2$ worth of drillbit!

When you've built as many tamiyas as I have you'll realise 25 bux is nothing to pay for a lifetime of smooth ball cups

That Muchmore tool does more than deburring, it actually perfectly & evenly increases the ID of the ballcups--in case you are using a different brand/type ballcup than ballstud.

I am all for saving money when you can but this Muchmore reamer is a useful tool.

Never had anything other than perfect ballcups from Tamiya myself. As far as the hole-drilling for access goes, I tried it on a couple of cars in the past and now I don't bother. It takes lot of unpopping of ball ends before they wear dramatically, and drilling the hole is a lot of effort which just makes the cup more likely to stretch anyway.

The reason I started this post was a "funny story"... I was going to say how much this car continues to perplex me, as I went racing today expecting all sorts of problems with varying levels of grip on the track (started dry but a brief rain shower took the grip away before my second run), but I was surprised by how consistent it was during the day, with and without the centre screw on the top deck attached. It was pretty much perfect (by my standards) using kit settings with the exception of the springs and the fluids...

...and getting back home I just noticed that at some point during the day the bottom centre screw had fallen out of the car! So I have no idea what kind of chassis flex I was running.

Sounds like you were having fun with the car though

The bottom screw is something you can remove to give the car more flex. I sometimes do this but use a 3mm set screw so the chassis can flex more but it keeps it a little more controlled on the flex.

So much for all the tuning sweat.

Personally I prefer not to drill because of all the crap that can get in then, but sometimes I hate popping off links so I drill them if I can't use open cups (I have a whole stash of Yokomo cups/balls with perfect fit, and play free unlike Tamiya's). A play free joint will show wear a lot sooner, Sosidge.

And here's a tip. The fluorine coated ball nuts for TRF dampers (Tamiya item #42231) are a perfect fit for the kit tie rod cups. I replaced all the balljoints on the car with these (pretty exxy, I think I used about five sets @ 10$ a pop?) and I drilled the cups when I realised I would wear them sooner if I kept popping them off. But the car is absolutely slop free now and smooth as butter. I like that in my cars.

I have been using xray 4.9mm ball joints with hole (302665) and 4.9mm ball ends. They have more material than the tamiya ones.

I hated drilling ballcups, too. Take a sharp body reamer and it'lll make a perfectly round factory appearing hole with no excess.

i'm curious to know what people are doing here - i've found the setup to have a little more play than i'd like - on the posts in particular anyway - is anyone else adding more than the kit shims here?

kit calls for a 0.1mm shim on top of each of the arms (at the post) and 0.1mm shim plus the 0.7mm spacer between the arms and the bridge.

i've tried an extra 0.1mm shim *under* the arm on the post and it is still a little sloppy, but 0.1mm under and 0.2mm over it binds.

I did nothing on the steering bridge but on the bellcrank posts, I added an additional 5x0.1mm spacer. Make sure not to overtorque the screws on top of the posts. My steering is still smooth but with just about 0 slop.

The key with shimming is to make sure that the parts have as little play as possible but still run absolutely freely. If 0.1mm extra makes it too tight, don't use the extra. RC cars are not like full size cars, the get really upset by anything other than a free-running fit.

I shim my cars, my TRF418 only has some extra shims on the steering cranks and the wheel axles If I recall correctly, and not much extra at that. I've also replaced the 0.5mm spacer on the hingepins with shims, but that is mainly because the 0.5mm spacer is too tight and I don't want to shave the arms.

Machined parts are going to have pretty fine tolerances, the moulded parts can have a wider tolerance so not every car will need to be shimmed the same.

Above or below the arms?

If you want to get real particular, 3Racing makes a 5mm ID shim set with finer thickness increments--perfect for tightening up the steering posts:

http://www.tqrcracing.com/shop/produ....asp?p_id=7244

Got it to 0 slop on the posts using something like that. It makes a big difference imo.

The suspension hinge spacers should all fit, including the 0.5mm and still have some wiggle room. Just make sure you apply outward pressure (from the arm's perspective) to the suspension blocks as you tighten them down. You can slightly adjust the wiggle room with the outer most block.