Hey all, been meaning to do this for absolutely ages but kept putting it off/getting distracted/procrastinating. But no more!

Finally time for a build diary to chronicle my Shunt replica build as, barring a couple of small alterations to more closely match the original, it's pretty much complete. Hopefully it'll be an enjoyable read for you all.

April 2018

I can't remember when I first had the idea to make a Shunt replica, but my earliest email to Jonno enquiring about the shell was December 2017, and he very kindly agreed to have a shell made from the mould he has. Fast forward a few months and I attended the 2018 Manchester Extreme Robots event to collect it (and took Drumroll along for some 'fun' - sorry Honey Badger!)

The reason for Shunt is that I initially wanted to make a Dead Metal replica, but it's difficult to get a reference point for size and scale with DM. Original Shunt is my second favourite house robot, and seeing it in the flesh at the time of the reboot was brilliant. Since Shunt has a fibreglass shell, this dictates the size of the main chassis. From there, I could then work out or guesstimate the size of things such as the scoop, wheel guards, plough and axe. This would involve a lot of studying of pictures and video footage to get an idea of how the original went together and how to plan mine - I lost count of the amount of hours I spent staring at zoomed in pictures and watching the Shunt section of the Ultimate Warrior DVD!

My aim was to keep the build secret for as long as possible, up until the reveal, though a few friends knew about it. I couldn't resist getting a picture of it next to ER's Matilda at Manchester, so hung around for a bit until people dispersed, then sat them side by side:

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The shell seemed quite small by comparison, though would obviously look more substantial with the extremities fitted. Still, it shows that for being considered the most powerful of the original four house robots, Shunt was also one of the smallest. With the shell in possession, the first thing I did when I got home was position a tyre and a drinks bottle in place. I remember reading that Shunt's exhaust stack in Series 1 and 2 was a lemonade drinks bottle, so wanted to make mine in the same vein:

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The wheel in the picture is 10" diameter. One thing that has never looked quite right with the Extreme Robots Matilda (and subsequently the Robotazia one) is the wheels, they've always looked too small, and that was true here too. After some more picture studying, I guessed that the correct size must be 12" kart wheels. Just one small problem, they're not easy to find! I eventually found one supplier in the UK that had them but it would be weeks before they were in stock, so I bought a pair of 10" kart tyres and split rims as a temporary placeholder.

May 2018

I was kept busy with work until the late May holiday weekend, so spent hours researching Shunt, determining how the chassis was constructed and what I'd run mine on, and got some materials ordered up. The guy in Argos was quite excited when I told him the steel he'd helped me carry to the car was being used to make a replica house robot :P
Shunt's main chassis seemed to be constructed from steel angle (all the house bots in Series 1 appeared to share the same basic chassis design) so by looking at the shell I had and what the various sections of it were like, I set about making a simple cuboid chassis that would slot into the lowest-most section of the shell:

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Due to my lack of machine precision cutting and thin plywood welding 'jig' the chassis is a bit rough around the edges and maybe not entirely square but no-one would see it. I settled on using 24V, 800W scooter motors for the drive as I had two spares from Coyote and they've done me well so far. I made some drive shafts from pieces of box-section upright and a length of silver steel which was welded to a collet which in turn was welded to the box section. Crude but effective. Then came some motor mounts and sprockets bolted to the wheels, and before long it was running around in the garden:

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One of the sizes I pondered over was that of the axe arm. Again I was looking at pictures of Shunt from the RW tent and the clips from the Ultimate Warrior DVD. Reckoned it was either 40mm or 50mm height, so made cardboard mock-ups of each and took a punt at 50mm. When the stock turned up, it looked spot on:

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It also weighed a lot! The scale of what I was working on was beginning to sink in.

I didn't do much to Shunt over the summer months. I was working in Aberdeen at the time and my workshop was 170 miles away at my parents' house. I had a couple of weeks off in July but had signed up for the inaugural Glasgow Maker Faire at the end of July. I should take this moment to mention that I anticipated Shunt to be a slow-burner build, maybe taking a couple of years before it came anywhere close to looking like it should, so the two weeks holiday were spent working on my mechanoid R.O.R.I. for Maker Faire as well as repairing and repainting Coyote after it fought in Dublin in January 2018.

The one Shunt thing I did work on (as well as swapping out to the 12" kart wheels which turned up) was to do some work on the exhaust stack. I found Highland Spring water bottles that looked to be about the right size, cut two in half and stuck the two neck ends together. One end would go into the body (and be secured by the lid) and the other half would be the top with the outlet pipe. One of my biggest quandaries was how to make the 'holes' in the exhaust stack, as it would need a layer of material with the holes drilled in that would wrap around the bottles. Then I stumbled across a glass drinks bottle from B&M that had a grey rubber grip on the outside with holes in it - perfect! I bought two so I had enough material to span the bottle and proceeded to butcher them for the grips. A quick test against the bottle, and it looked the part:

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The exhaust outlet was made from 22mm copper pipe and a 90 degree fitting. A length of copper pipe also ran all the way through the bottle as I had plans to maybe fit a smoke machine and have some smoke puffing out of it for dramatic effect.

That's all for this installment, next one coming soon!