How to make a robot frame

hi all

some of you may be aware that i am soon to make a new body and frame for psycho fling. i have the mateerials sourced thanks to shane, but i now need to know how to secure the frame together once its all cut?

thanks alex

either weld it or bolt it together.

What material is the frame to be made from?

i think it is steel square box section 2cm with a 1.2mm wall

im just about to put a priliminary sketch on my profile of what i might do

alex

cant seem to get it up

ill put it on my website and post the address

alex

ok its on the website

http://www.psychoflingteam.co.uk/http://www.psychoflingteam.co.uk/

just click the face then robot improvements

thanks alex

If you can find someone that can weld it and do a good job then I would go for that. Otherwise the easiest option is to bolt it together. A good weld will be better than a bolt but a poor one will be worse.

Where abouts are you Alex ? If you cut everything Im happy to weld it up for you

We are based in heanor derbyshire, are you based in bury (profile) but my grandparents live near bury

thanks alex

Bury Lancs Nr Manchester. If you cut the steel and mark what wants to go where you could post it ?

yeh ok ill email or post when its all cut it may be a few weeks though

cheers alex

Were in Leicester (J23 off M1), but workshop is just off M1 J24 on A453 (opposite power station). Youre welcome to pop down and ill weld it up for you one evening.

Alan

thanks guys

ill see the weight of it all then decide the best option

thanks for the help

alex

quick question about welding how did everyone learn? and can you teach yourself? not that i would just wondering how people got into it

thanks alex

Trial and error. If your learning yourself be prepared to make mistakes.
The other way is have a look at your local tech. They sometimes run short courses and dont mind you bringing your own stuff to weld up.

Local tech? well like i say i dont want to start buying all the expensive equipment or anything but just to get started perphaps

alex

Alex, I learned at work, still not very good but dont get that much practise. Local tech, I assume Simon means look up see if there are any higher education technical colleges around.

I taught myself. I bought a cheap stick arc welder out of macro for £30 and a pack of welding rods off ebay for a fiver. Then I read as much as I could off the net and spoke to a few people that I knew could weld. After practising again and again I can now lay down a relatively nice clean weld. Still using the cheap welder!

http://www.aussieweld.com.au/arcwelding/http://www.aussieweld.com.au/arcwelding/
Worth a read.

The robot improvements page has been update, including the materials i will use

any opinions welcome

Could someone advise me on the material i should use for the lifter pannel? it will only be about 14cm wide but i may brace it with some box section if need be.

thanks alex

stainless :)

anything will do - from ali, steel,titanium, polycarb, hdpe. If you want it all welded up solid then steel/stainlesssteels your only real choice.

if i do go stainless what thickness?

cheers alex

I am new to this but looking at your video it looks to me as though you should try to have the actuator at the other end (away from the hinge) so that it not just a piece of sheet material trying to lift a 12k bot. Any thoughts anybody as I could be totally wrong

what so the lifter arm is attached lower down?

alex

Yes, as the sharp end of your robot is the point that will be trying to lift the opposition thats where the most weight will be and therefore where the actuator should join the bodywork. Again, I could be wrong as I am new to this but it does seem to make sense to me.

Alex, is this the new design to help it self right easier? if so i dont see any difference to the previous one to help it as the lifter still wont lift much higher than before.

it wasnt meant for that, but if i could incorparate that it would better. the main aim was to to cut down on the weight of things (previously 12.8kg) and improve manoeuverability and the lifter to lift other robots

do you think tjis could be done? if so how?

Thanks alex

In that case i guess its fine - but if you want to self right with that mechanism and that design i think you would probably need a front hinged flipper. To lift another robot, the closer the mechanism is linked to the front of the lifter the more it will lift, but it wont lift as high.

There is also the option of having an extra bar attached to the lifter which starts extending when the lifter reaches a certain point, helping with the self-righting (like what Ploughbot/Vertigo have/had) Whether you could get it into the weight limit, I do not know, guess it just depends what the mech is made out of.

In regard to your lifter attachment point - attaching it lower down will give it more power to lift with but I think with the way the Zeobot mechanism works, it may also increase the time it takes to achieve full lift. If you wanted to keep the attachment point as it is (thus keeping your lifters travel and time taken high) you could always bolt on a couple of lengths of box section steel (16mm squared stuff from the likes of Homebase would probably do) running the full length of the lifting arm - that will add some rigidity to the lifter plate.

yeh i was certainly thinking of bracing the lifter pannel

thanks jamie

I have tried to cut the box section proving difficult, i am currently modifying my vice to make it easily as im using a hack saw.

could anyone give some advice on how to make it easier or an easier way of cuttting it?

thanks alex

What problems are you having?

Is your blade brand new or is it well worn?

Are you using the full length of the blade when you cut?

Is it the Homebase stuff? If so, I cut mine with a hacksaw but it did take a fair bit of perseverance with the saw. Two options I can think of:

Put a new sawblade on your hacksaw (although thats only really necesary if your current one is a bit blunt)

Or, invest in an angle grinder - there are some for £20 in the likes of Argos etc that would be fine for cutting through the box section.

I suppose there are other otions like flame torches and laser cutters but that would just be me being complicated :)

The box section is from shane and my hack saw blade is newish

are the angle grinders easy to use and would i use a vice?

cheers alex

You will need a vice or some other secure way of holding the bit you are cutting. Angle grinders are fairly easy to use, yes. Be sure to buy safety goggles and ear defenders as well.

i know this is cheap and cheerful but will it do the job?

http://www.godfrey-diy.co.uk/power-tools/grinders/10/item32009100.htmlhttp://www.godfrey-diy.co.uk/power-t...m32009100.html

and what about the blade?

http://www.godfrey-diy.co.uk/power-tools/power-tool-accessories/12/item33003190.htmlhttp://www.godfrey-diy.co.uk/power-t...2/item33003190. html
Should do the job

i think ill try my hack saw again as my dad says he doesnt want me using a grinder :angry:

thanks all the same alex