Greyhound Upgrade

[CharlesD]

I did an upgrade of the Greyhound, it appears to be faster than the original one, i have no way of measuring it though.

2 x Buwizz 3.0
PU Servo
4 x Cada Pro L motor
Redesigned wheel hubs without turntables
(some) Superglue

Would you like to know more?

[Daniel-99]

2 x Buwizz 3.0 units - is a serious improvement ;-) I used them together in some of my cars until they get drowned... 

Does axes hold such big wheels while cornering? High speed + tight corner = extremal load on an outer front wheel which could pull it off the axe. (again, tested with my cars).

[CharlesD]

I used carbon fibre axles at the end, superglued to a metal universal joint in front and an axle connector in the back.

They grip well on plastic, i just added some superglue to the axles that did not grip well, let it dry and it grips fantasticly.

[Daniel-99]

I see. I use a superglue from time to time as well ;-) 

I made my own 4x4 off-roader with 4 PF L-motors powering each wheel. 

But it has one very weak place - a plastic CV joints at the front axle. I wish Lego would sell metal once! 

Also It would be so cool to drive both of our cars together ;-) I suppose yours will be a bit faster!

 

[gyenesvi]

Why did you need to redesign the wheel hubs? The original design based on the turntables seemed very sturdy, and you replaced it with something that relies on a single axle that does not hold by itself so you had to use superglue (this is how I understand it). How is that an upgrade? What was wrong with the original design?

[CharlesD]

The turntables give a lot of friction, i gathered that removing them would increase the speed and save some weight.

But having no way of measuring it i do not know if it actually did, the CADA motors in theory output ~2 times the power of the regular motors, so the best way to test if it really helps would be to install the turntable hubs.

The motors and buwizz 3 and PU servo alone would be an upgrade, don't you think?

I actually came up with this idea because of another car i am working on with porsche rims, the turntables are not very wel mountable with those. That works good, so i decided to test it with the greyhound, since i had all the parts laying around.

 

Edited August 9, 2022 by CharlesD

[gyenesvi]

I think the turntable design needs greasing to work well, that's how it should be compared, but I have never tried it (yet) so cannot really tell, just read it in its thread I guess.

Sure the power may be boosted by the cada motors and buwizz 3, though the build does not really change by putting in more powerful ones, so that's not a real upgrade for me. Maybe the PU servo needs a bit of rebuilding because of the different form factor, but still probably not too substantial, and you haven't mentioned if that resulted in better steering or not (in your video you don't seem to be able to control it too well).

[amorti]

The turntables need grease to run well. They have the advantage that they'll never melt unlike an axle in a hole can. You can tighten up the wheel to the hub like this:

Pins in pin holes, means less play. You just have to get over the use of the middle 1L of the 2L part of the pin.

Also you can then turn the wheel inside out, to get its axle hole nearer the driving axle, so again less play:

 

 

Edited August 9, 2022 by amorti

[CharlesD]

Even with grease they do not rotate all that well, and no the PU servo is not really better, controlling this with a smartphone while trying to film at the same time is also not very easy.

But if you have only buwizz3 with 4 PF outlets you kinda have to use a PU servo.

That mounting on the turntable does not work for Porsche rims, which was my ultimate goal.

 

Edited August 9, 2022 by CharlesD

[CharlesD]

I made an offroad video, what do you think @Didumos69 ?

 

[Johnny1360]

Man, for a minute, I thought the front was the back because of the tire orientation. Looks good and fun.

[CharlesD]

Fun it is for sure, any faster and it would be very hard to control.