From The Ground Up (Advice Thread)

[Roland]

Re: From The Ground Up (Advice Thread)

Ok, so if it's built in (Edit:BEC) it's mandatory?
And if I where to buy a seperate battery pack for the receiver, how would I wire it through the safety switch? OR would I then need two, or perhaps none at all for the reciever battery?
Very helpful thanks.

[woody]

Re: From The Ground Up (Advice Thread)

Ok, so if it's built in (Edit:BEC) it's mandatory?

NO ..OPTIONAL

And if I where to buy a seperate battery pack for the receiver, how would I wire it through the safety switch? OR would I then need two, or perhaps none at all for the reciever battery?
Very helpful thanks.

You want a removable link in one of the main battery supply wires...this acts as a switch

[psychostorm]

Re: From The Ground Up (Advice Thread)

A BEC is not mandatory, but is one less thing to fail. Hence simplicity until is breaks...


It's best you have a switch for a rx, preferably next to the link. Mainly to stop the battery from draining between the arena and the pits, though partly for safety.

[Roland]

Re: From The Ground Up (Advice Thread)

Thanks everybody. I've been pondering over the design for a while, and I've decided that want a sturdy machine, as small as I can get it, I had a look at ratios and by the size of my wheels the rest of the chassis should come to around 400mm*256mm! My current problem is I can't fit the drill motors onto the wheels, I've thought of two ways to fix it, the first being my preferred of having the motors parallel to the wheels, but slightly down a bit, and attaching it to the axel on the wheels using bevel gears and of course the other which is to simply expand the machine - which I currently don't want to do for a few reasons: the larger it gets the more surface area I have to cover with armour increasing weight; I'll have to put more support onto the frame and the fact that I expand it means I'm going to have a large amount of empty space, which I want to prevent. So which one would have a larger advantage? :O
My design so far is here: EDIT: IT'S SO BIG HOW DO I MAKE IT SMALLER

[daliad100]

Re: From The Ground Up (Advice Thread)

A picture that large should probably be linked to or I think just uploading it as an attachment and not inserting it will make it smaller.

If you can get chains/belts you can have the motors diagonally with for example the rear motor powering the left side and the front motor powering the right side.

You could also try making the robot shorter and wider so its 400mm wide and 256mm long so it will weigh about the same but you will fit in four drill motors far easier with no extra gears

[Roland]

Re: From The Ground Up (Advice Thread)

Solved the problem earlier but I couldn't edit the post, it's now 470*300*70. I'm all set to go, but I'm not sure on what thickness the steel box section should be, I was thinking 20mm*20mm*2mm but that might be too heavy. Any ideas?
Thanks for the contribution though, I'll keep it in mind.

[Roland]

Re: From The Ground Up (Advice Thread)

problem solved. woop.

[gizz]

Re: From The Ground Up (Advice Thread)

i believe 1mm thickness would do the trick actually. my old fw frame was mad eof 2mm thick box section and it felt like an overkill.
But thena gain i never fought with that chassie so im not 100% sure.

[Roland]

Re: From The Ground Up (Advice Thread)

Oh good. 1mm is what I wanted, the frame was going to come to 7kg which I thought was a slight bit too much, so dropping it to 1mm should reduce that numbrero.
I can't find any duel speed controllers anywheeeeeeere.
Does anybody know where I should look?

[psycho_fling]

Re: From The Ground Up (Advice Thread)

technobots

robot market place

[Roland]

Re: From The Ground Up (Advice Thread)

Having look now.
I'm confused then, what should I be using for structural walls? If I used 1mm steel I wouldn't be able to weld it, so what would be the best method to attach it all together?
Or should I use a fairly thick aluminium alloy? Euuurgh. I don't know and there's nowhere else but here to ask. ;_;
I feel like a bug. xD

[daliad100]

Re: From The Ground Up (Advice Thread)

Welding thinner metals is much easier with a mig or tig welder but with good welding skills and thin welding rods you can theoretically weld thin metal with an arc welder.

I remember seing someone clamping a piece of material (copper or aluminium should do the trick) behind the weld to be a heatsink and help prevent blow through. I would suggest you practice on some scrap pieces first though.

If you don't want to weld then bolts and angle plates are probably the next best bet.

[gizz]

Re: From The Ground Up (Advice Thread)

Hijacking this thread for a quick question.

I'm in the midst of building my first real FW which is going to be powered by 2 standard drill motors and 1 additional for the weapon.
I'm aiming for it to be compact and was wondering exactly how far from the motors I need to put my 2,4ghz Spectrum RX?
I've seen very tight builds and was curious if there are any significant interference from motors when using 2,4ghz equipment?

I will twist the cables to the battery and the motors but havn't planned on using capacitors on the motors unless i experience interference.
I'm also thinking of shielding the RX with a folded piece of aluminm but not sure if it would help.

[botmad]

Re: From The Ground Up (Advice Thread)

The spectrum 2.4ghz eliminates 99.9% of interfearence so not to worry .....

[Roland]

Re: From The Ground Up (Advice Thread)

I was wondering why general purpose tufnol wasn't used in featherweight machines, what reasons are there behind that?

Thanks.