RogueTwo Robots

**RogueTwoRobots** · 11th November 2013, 19:09

Update

The continued lack of employment has stopped any decent robot progress recently but in a few weeks I'll be moving up to Aberdeen to start a new job. Downside is that I'll be in a 1-bed flat with no workshop to hand, so been spending a fair bit of time in the Cave of Blunders while I can. After servicing the robots from the Deeside event, I needed something else to do, and got thinking:

Originally Posted by Eventorizon

How much weight do you have? You could put a saw of some kind in the middle and go for something like Deadmetal! Removable so you can use it at scot bots of course.

Always fancied the idea for Carcinus but ended up building the axe for it instead, then developing Onyx when the axe put Carcinus overweight. But a quick search around my various spares and I realised I pretty much had all the parts to do a Dead Metal style saw, similar to the Series 1 design.

Firstly I needed a method of swinging the arm. I had enough chain spare from Onyx and some sprockets to make a 3:1 chain transmission from a drill, but knew that would still be too fast, so decided to have a bash at making a three-stage drill gearbox.
Welded two ring gears together (absolutely shoddy welding I know, but sufficient), trimmed them down and stuck the gears in:

Then because the plastic gearbox plate that mates to the motor wouldn't fit on, I needed a way to join it all together. Cue some parts from an old GR-01, using the motor plate at the rear and the front plate (minus the bearing) to bolt everything together. Bit of a hybrid unit. Stuck the 10-tooth sprocket on the drill output and that was done:

Then made some bulkheads to secure the motor and mount the bearings for the arm shaft. It would be neater and lighter if I got some needle rollers and pressed them into the bulkheads but these were in the spares pile I was working from and have been sitting doing nothing since 2007:

The saw arm is a bit of box-section that I pulled out of Scar's insides, cleaned up with a couple of nuts welded on. M6 bolts go through these nuts and tighten against a couple of flats on the shaft (M12 bolt) and grub screws secure the large sprocket and bearings to the shaft, resulting in the whole thing rotating when the motor spins:

I had hoped to use an old angle grinder gearbox to connect the saw blade to the motor but it proved unsuitable so I'm going to have to make something custom and more reliable once I've started earning again and have the time. Currently it just has a cutting disc bolted on through some Nylon to complete the look; I hooked up the HTI motor I was planning on using via timing belts and pulleys and it sounds menacing but there are no bearings between the sawblade shaft and the nylon that's holding it on so things got hot and melty pretty quickly.

Still need to weigh it to see where it's currently sitting but pretty happy with it so far. Got an Electronize controlling the arm and got a spare SSR for the blade motor, though the Electronize will get upgraded to a TZ85 at a later date to give more precise control.

And finally, if you were able to sit through that, the customary video:

**typhoon_driver** · 11th November 2013, 19:35

Bud you will me more than welcome to come up and do the robot stuff in my new garage. Only 25 mile or so out of town

**Porker** · 13th November 2013, 18:25

What motor will you use to spin that disc?

**RogueTwoRobots** · 1st January 2014, 22:58

Sorry George, only just spotted your post. The disc will either be spun up by an HTI motor or Speed 900; will need to wait until I get a transmission sorted out before trying them both out and seeing what works best.

Update

Spent the past few days on CAD giving Drumroll a virtual rebuild. It was in a bit of a sorry state after the 2013 champs and hasn't been touched since April, with the focus being on Carcinus, Onyx and Scot-Bots. With murmers of the 2014 event starting to surface, I've started planning what to do with it. Here's how the current CAD looks:

As you can see it's not hugely different visually but the chassis and insides have been changed up a bit. The Nylon chassis is going in favour of 6082 T6 aluminium. I've found an online supplier that provides pieces cut to size and the total cost of the aluminium for the chassis is going to be around £28, which is cheaper than getting a sheet of Nylon to rebuild from so it's a bit of a no-brainer.

The drives are being upgraded to Banebots as they were the biggest issue last year in terms of reliability so I want to eliminate (or at least majorly reduce) that.

The lipo will be getting upsized, I'll be switching to TZ85s, and the ring-tooth drum will also return. Not all of this will be done for the 2014 champs. The training I'm doing for work is quite intensive for the first six months to a year so the upgrades will be getting applied in stages. Stage 1 is replacing the chassis with the aluminium, Stage 2 is fitting the new drives and Stage 3 is the weapon.

I'm hopeful of getting it to Stage 2 in time for the champs but even if I only manage to get the chassis swapped out, it'll be an improvement. The ali will be getting ordered tomorrow now that all the sizes are sorted out. And it's worth noting that any similarities to drumbots living or dead is purely coincidental. I totally didn't raid Dave's 720 build thread for ideas

**mattsdragons** · 2nd January 2014, 08:55

How much do the banebot drive units come out at all in? They look really solid drive motors

Also, what gearbox are you aiming for?

Cheers

**mrsam** · 2nd January 2014, 09:23

New drumroll design looks amazing can't wait to see it, if you don't mind me asking what's the name of the aluminium supplier that you found?

**RogueTwoRobots** · 2nd January 2014, 11:15

Not sure how much the Banebots order will cost in total, I've currently got a few spares of things in the basket as well and there is still shipping and possible customs charges to go on it once I've placed the order but I expect it to be at least $250. The gearboxes are just the stock P60s.

The aluminium supplier is: http://www.aluminiumwarehouse.co.uk/

Just placed my order. The standard delivery charge is £12.49 so if it's only a small order, that will make up a large percentage of the cost, but it should balance out a bit if you order more stuff. They seem to have a pretty extensive range as well, so if the service is good, I can see myself using them again in the future.