British Menace

The whole point is to measure it! Your point of reference being the way the car acted on the track. When you really liked the feel of the car. You can then check the tension of the diff' with this machine. then replicate it when you return to the track with the same car in similar condition's you know that tension was good.

In reality you may find you had 100K in the diff' when you really liked it. The diff' machine show's a tension of X amount. On your return and re-build of the diff, you may have to put 80K oil in to achieve the same tension (X amount) as you had when you liked the car/ diff'. (Maybe due to using new gears, for example)
The point being is you can then know if putting 100K in your diff this time is going work the same as last time you used it....

On the spring front. We do not use fully calibrated springs. They are manufactured using set wire thickness and number of coils. While this does get the spring in "the ball park" of the spring strength, say 37lb. It may be very inconsistent between springs. It's always a good idea to test spring's to see what their actual rate is. En devour to match them in pairs to optimize their performance.
Consistency of testing being vital. This machine would help in trying to attain some consistency in their testing.

Regards
BM

PS. May I just say that for the like's of probably myself and many mortal club driver's. A difference, felt by a machine like this, with the same diff, same fluid in etc, we, as driver's, would probably not feel the difference. Even though the machine showed a different tension!

nitrodude

iTrader: (8)

Ovethinking it... KISS method...

thunderbt3

iTrader: (14)

+1

I don't think I've ever seen the non-mortals (Collari, Pietsch, Grosskamp, Lemieux..etc) use such a device, unless they get special calibrated & matched springs from the factory...

They'll still be able to whoop me with a Walmart 8AA cell RC...

lil-bump

iTrader: (89)

+1

I've never asked a fellow driver (What was your diff resistance in the rear?)but I will ask what weight fluid and brand.)

Pass you soon...

British Menace

It's all I have as I am not gifted with the talent of the non mortals.

British Menace

Maybe you were not able to ask as I'm not sure there's a machine available yet that provides that information.

British Menace

Vast majority of the non mortals, and many other drivers are not designer's or vehicle dynamic's expert's. Usually, they have an immense talent to drive rc car's and practical knowledge of setting up rc car's.

No disrespect meant to any one, or to those who, like myself, have vehicle design or dynamic's training.
Even with all the knowledge in the world, I can hardly compete at club level never mind any higher.
I have the utmost respect to all those people with such talent!!
As much as I would love to say otherwise, knowledge is all I have in Motorsport even if I can't relay it very well.

Regards
BM

Roelof

I think a lot of people just want tools so they do not have to rely on their own feeling and think the tooling is making it all right. If you just work straight on with a clear mind then there are no such tools needed.

blis

I saw these tools posted a couple of years ago, Im sure of it. If you separate the racing and the hobby, these tools are representative of the modelling. Some people enjoy the bigger picture and if they get a kick out of inventing and innovating then its good for everyone.

Whether I'd go to all the trouble of measuring to that detail, Im not sure I would. If I had the tools, it's sure good to know I can!

Roelof, it's much like a bearing tool remover debate. No you don't need one, but when you have one, you wish you'd done it earlier. I also own a Losi shock tester I rarely use but still like the tool and it did solve problems on a 1/5th scale shock system.

robk

iTrader: (22)

There is a guy who has built something similar that is mostly for electric sedans. The idea came when somebody said they were running "5000 wt" in their diff and it felt like 1000wt. The idea was to be able to compare across cars, with all the differences in design and materials, and with the build technique, in terms of amount of fluid, shims, etc. Is it necessary, no, but if nothing else it shows what things like amount of fluid in the diff in the same weight will do.

RedBullFiXX

iTrader: (34)

How many of these tools seemed "Necessary" before they were introduced to RC ?











etc...

am

A good example is the buku brake tool for 8th-scale offroad. It works briliantly!!!!! You can set your brakebias the same evry time! I would assume knowing what your diff is like is quite important.

i use Losi oils, but the last 8 tubes i bought has different Wt even the numbers on the tubes are the same ( 4 tubes of 3000 and 4 tubes of 5000).

bertrandsv87

iTrader: (2)

I hope this machine does not start a diff of the week frenzy, where racers will buy 100 diffs to build a single perfect one...

blis

Jokes aside, I'm inquisitive as to what a couple of those actually do?

PS: Without enthusiastic inventor like this, we'd still be running a eyeball carved wooden chassis, measure something and you can structurally qualify it to stand up to the task.

rcmadkiwi

iTrader: (3)

I agree, what's wrong with fitting each diff, testing them on the track & comparing the outcomes? That machine won't tell you everything.