building a drum spinner

**Max** · 29th June 2011, 22:38

My drum design is pretty similar to drumroll's but I defiantly can't afford to use 3mm steel for the drum, it's either 1.5mm or a push 2mm thick steel or 3 or 4mm aluminium ( not 100% sure on the thickness for aluminium as I havn't done the math. Which material do you think would be best?

**typhoon_driver** · 29th June 2011, 22:56

Then make it 2mm thick. Not only will you have a hard time welding to 1.5mm without blowing through it, but a vertical hit to it will make a decent dent if not go through. I'd also advise stainless steel if possible. You can pick some stainless tubing up pretty cheap on ebay (it's used for those stupid boy racer exhausts).

I wouldn't use aluminium. You can't weld steel teeth to it.

**Max** · 30th June 2011, 07:00

Could I use hardened steel?

**Max** · 30th June 2011, 20:59

Hi, sorry to re-post this but I want to get the drum made soon, can/should I make the drum out of hardened steel?
Also do people use some kind of glue as well as screws to fix hdpe together?

**typhoon_driver** · 30th June 2011, 21:27

what do you mean by hardened steel? Mild steel that's been tempered or some other material?

Glue's don't work well with HDPE. The best way to join it is to heat it up and melt the edges of the panels together.

**Max** · 30th June 2011, 22:14

I mean heating then cooling the steel drum once it's made to strengthen/harden it

**typhoon_driver** · 30th June 2011, 22:18

Yeah sure, should be fine. Just make sure you temper it to the correct hardness. You don't want it to be brittle.

**Max** · 8th July 2011, 19:05

Hi again,
The drum is being made and i don't want to start putting together the rest of the robot until it comes in case it is not done to my exact specification meaning I will have to change to design slightly to fit it in.
One quick question, i have (and only have the weight to have) two 12v batteries. Before I thought I would use on for the drive and one for the weapon, now however I want the weapon to run off 24v but still want the drive to only be 12v because otherwise I fear the batteries will run low in the battle and I get no gain as it is not a pusher from the extra drive power.
Is there any way of getting these two voltagesfrom my two batteries?
Thanks

**Max** · 9th July 2011, 18:19

How much ground clearance do you think I'll need because at the moment I will only have a few millimetres and am worried that the bot may get beached on the ground!