Gear materials in wCK 1108/1111 servos / 11.1v power ...

[NullARC]

I am interested in purchasing a Robobuilder 5710k kit. I would like to eventually upgrade to the metal bracket set and run an 11.1v Li-Po for more torque and speed as I advance. In reading the incredible amount of information you provide, I saw the need to upgrade the internal gears in the wCK servo modules. But because there is so much information, I'm a little confused as to what gears in the currently provided 5710K kit are plastic and which are metal and what I would eventually have to purchase to make them durable enough for the 11.1v power upgrade.

I noticed a couple of references to a 5740K kit that had all of these upgrades. However I am unable to find this anywhere, including the Robobuilder home website. Was that kit just never made available?

Also, as I upgrade, what might I also find useful?

Thanks so much for your time and help!

- Marc

[PedroR]

I saw the need to upgrade the internal gears in the wCK servo modules. But because there is so much information, I'm a little confused as to what gears in the currently provided 5710K kit are plastic and which are metal and what I would eventually have to purchase to make them durable enough for the 11.1v power upgrade.

Because of all that amount of information we've put together an upgrade guide that is available here: http://robosavvy.com/RoboSavvyPages/Rob ... eGuide.pdf

In essence if you're buying a new Robot (produced after March 2009) which is most likely the case, you need:

- 1x "Pack of Metal Gear 1 for 1111 (4 units)" which includes 4 metal gears.
- 12x "Pack of Metat Gear 1, 2 & 3 for 1108" which includes 12 sets of gear 1, 2 &3 for the 1108 servos.

The only difference between "old" and "new" Robobuiders is that the old ones did not have gear number 4 in Metal. The new ones now have it, so it's one less gear that you need to purchase.

In these new kits the following gears are used:
- 12 Servos 1108: Gear 1, 2 & 3 are Plastic. Gear 4 is Metal
- 4 Servos 1111: Gear 1 is Plastic. Gear 2, 3 are metal. Gear 4 is metal.


If you're looking into buying extension kits and additional servos please be careful since depending on the kit, the material of the included gears varies.
All of this information is included in the
http://robosavvy.com/RoboSavvyPages/Rob ... eGuide.pdf

I noticed a couple of references to a 5740K kit that had all of these upgrades. However I am unable to find this anywhere, including the Robobuilder home website. Was that kit just never made available?

The 5740K was a promotional robot developed by Robobuilder which consists of a 16 DOF Robobuilder with all 1111 servos, all Metal Gears and an 11.1V Lipo.
This robot was, at the time, much more expensive than the standard 5710K and I am not sure if it is still in production.

With regards to purchasing a LiPo for your Robobuilder I'm afraid we are unable to supply those anymore as Robobuilder cut the supply for them (apparently due to some issue with their LiPo supplier).
I am not sure but I believe this issue with LiPos has also dictated the end of the short career of the 5740K.
I believe the 5740K surfaced more as a demo robot than any other thing. From what know it's commercial career has been dim.

If you have any additional questions, please post here.

Regards
Pedro

[NullARC]

Pedro,

Thanks for your help. I have noticed in so many of the posts, your quick and detailed input. I just wanted to say how nice it is to have someone to thoughtfully answer our questions!

As far as Li-Po's go, I have plenty of experience with them. I am heavily into R/C. So getting a Li-Po that will be compatible with the Robobuilder shouldn't be a problem for me.

I'm sure I'll have lots more questions over time and hopefully I'll be able to contribute to the community instead of just leaching! =)


Thanks again!

- Marc

[NullARC]

I believe that I read somewhere that the speed/torque difference between the wCK 1108 and 1111 is only the gearing. If that is correct and I am not mistaken then it would be possible, when upgrading to metal gears, to buy enough 1111 gears for all 16 wCK modules, thereby essentially making all 16 modules have 1111 speed and torque. Am I correct in this assumption, or is there something that I am missing?

[PedroR]

Hi NullArc

Yes you are correct.
The electronics seem the same.

However bear in mind that to make 1108 servos into 1111 servos you need to purchase Metal Gears specific to 1111 servos.

It's not just gear 4 that is different. Gears 2 and 3 are also different in 1108 and 1111.
We do not stock gear 2 and 3 for 1111 servos because those servos already include those gears in metal.

This means that we (Robosavvy) don't have all the necessary gears in stock to upgrade an 1108 into an 1111 (we don't have gears 2 and 3 for 1111).

In addition, if you choose to this you will throw away the Metal Gear 4 for 1108 that is included in the 12x 1108 servos in a Robobuilder kit.
This means you'd have to purchase 12x Gear 4 and the cost of the upgrade to full mtl gears raises significantly because each gear number 4 if quite expensive when purchased separately.
If you choose to maintain the 1108 servos, you do save some money because you don't need to purchase Gears 4 which are the most expensive. Those should already be included with the servos in the kit.


As a final note, bear in mind that a higher torque servo has a lower speed and vice versa.

Pedro