FW Electric hammer - Robo Challenge (no name yet)

[mattsdragons]

Really like this build, looks great!

Can you explain how the cam system works? Looks really interesting and im guessing its something to do with saving switching the motor back and forth?

[grant_ploughbot]

I spent abit of time yesterday machining out the lower cams. I think they came out quite nicely.
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Its taken a reasonable amount of manual machining aswell, and the modification of a cutter to finish them off. When the cylindrical grinder doesn't work - gaffa tape an angle grinder to the lathe
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[Ellis]

Grinders and gaffa tape, my kind of engineering!

Looking great man, how you're going to build this in time I have no idea but I wish you luck!

[Eventorizon]

Dave, I machined once... with you... remember? All trying to put a hole in the centre of that steering column.

[grant_ploughbot]

I've been doing a little more work on my robot and managed to get it working in time for filming on Thursday.
The only material I could get for the axe handle itself was a 3m long, 71mm x 44mm price of 7075 aluminium. It added a fair amount of time having to mill it down to the 40mmx30mm size I needed.

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I spent a number of hours lightening the axe and machining it to fit nicely
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Most the components are machined ready for assembly.
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And a picture of the weapon mech mostly assembled.
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I had to make a very bodged base, drive and armour for it intime for filming, so excuse the bad looks!
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I've got a video I posted on Facebook that I will try posting on here of the testing. I ran it on 5S lipos and only 1kg on the axe head and I'm quite happy with the results

[shakesc]

Looking very nice, look forward to seeing this in competition

[razerdave]

I know you said the mag is pulling over 100A on 24v, what's it pulling on the 5S (18.5v) test? My plans for Hell's angel may have changed and it involves a mag motor, hence my asking.

[grant_ploughbot]

I'm not too sure on this setup, I would need to stick a meter on and check. As the axe head is only 1kg and not 2 it doesn't seem to be pulling a lot. After it's first fight on Thursday with lots of fires the mag was barely warm which is good.

[Ellis]

Any footage of that fight, or is it TV-only for now?

[grant_ploughbot]

http://m.youtube.com/watch?v=Mm1UaraxD7E
Here's the first test vid on only 5S.

[shakesc]

Impressive

[PJ-27]

How are you controlling the axe? Beefy relays and quick reactions on the controller?

[razerdave]

From Grant, when I inquired:

To fire it at the moment I'm using an Albright contactor for motor reversing ( DC88-556PL, Albright 24v DC, motor reversing solenoid, intermittent, 100A, IP66)

[PJ-27]

Thanks

[sam_smith]

Looking really impressive Grant.
Engineering on the axe mech looks awesome - look forward to seeing it in action in competition.