Design Dilemma

[typhoon_driver]

You can measurebate all you want but you won't use much more than the capacity from a 3Ah pack. I've run a few high powered discs and never used much more than 2 to 2.5Ah from a pack and that's running it non stop for an entire 3 minutes

[Eventorizon]

Ewan, you mentioned using Nylon as a chassis material. Where would you advise getting it from an do you know what the density is. Solidworks is giving me 2 options, one with a density of 1400kg/m^3 called Nylon 6/10 and another at 1150kg/m^3 called Nylon 101?

At 10mm thick for all parts the chassis weighs 2Kg in 6/10... which given as I have cut the back off seems a little strange...?

[Ellis]

Here you can buy sheets of Nylon 6. http://www.directplasticsonline.co.uk/N ... Sheet.html

I believe many people use that site for HDPE and such as well.

[Eventorizon]

I found this site...

http://www.nyltek.com/pdf/SAFETY.pdf

in an attempt to find the density of Nylon 6 and it has given me...

Specific Gravity / Density: 1.0840g/cm3

and this one for Nylon 66

http://www.theplasticshop.co.uk/plastic ... _sheet.pdf

which says 1.14 g/cm3

Does anyone think that these are wrong or unreliable?

[ewan]

The link that Ellis gave (http://www.directplasticsonline.co.uk/N ... Sheet.html) is a good source and where I get mine. Here's the datasheet for the natural (white) Nylon 6 they stock http://www.directplasticsonline.co.uk/p ... t_Cast.pdf with a density of 1.15g/cm^3

A 2kg chassis seems reasonable for a feather- where's the remainder of your weight going if it's still too much?

[Eventorizon]

I will have 2 GR-1 motors (Got them today ), 2x 30A electronize ESC's, 1x 40A Electronize ESC, 1x Speed 900, 2x Technobots Blue wheels, then probably a linear actuator to act as a shrimech and flipper, and I am looking into getting lipols onsteda of my NiMH's so combine that with loosing 2 motors and 10cm of body work it should all fit in

[Laser]

1x 40A Electronize ESC, 1x Speed 900

If the 40a speedo was for the speed 900 I would get a bigger speedo to be on the safe side e.g victor 883

2x Technobots Blue wheels

What are they? Do you mean robo challenge or banebots?

[Eventorizon]

Done it again, the Robochallenge blue wheels and yeah the 40A ESC was for the Speed 900BB, will it definately blow cos I have already ordered it!

[Laser]

well most people who use speed 900's use victors.
as its a spinner your motor will stall if you have a low ratio and hit another robot, so its just to be on the safe side soo you dont blow the speedo.
another way to get round this is to put a fuse in so you dont blow the speedo, and blow the fuse instead

[Eventorizon]

I was going to go for a 4:1 ratio with speed 900 so the disc will spin at about 1400RPM, is that enough of a drop?

I was also going to fit a massive heat sink if that will make a difference...