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DIY Spit Roast Lamb


A few years ago – 2009 – and it was time to have a momentous stag weekend for my friend John, I was best man. We had use of another friends hideaway down in the lakes of Fermanagh on an island, so plans were hatched. The big dinner was planned for the Saturday night – fine dining it would not be, however: the dining was to be fine. I got to work on the idea of building a spit to roast some meat. Pigs are enormous and would have been too much for the 20 or so, albeit hungry, lads. One idea was to get a range of cuts to roast – which would have been good but tricky to get the cooking right I reckoned – we settled on spit roasting a lamb. Here’s the story of  the building of the spit and its subsequent use.

Getting Started

Lots of research first. There’s a section on spit roasting in the River Cottage Meat book by Hugh Fearnley Whittingstall in which he guides you through the process, using a spit which is turned 45º manually through the many hours cooking. Help was also found in many places on the web including these guys who no longer seem to have that section up, and the following three links which all proved invaluable in preparation:

3Men With Nothing Better To Do
The Firepit and Grilling Guru
Three Guys from Miami

Designing & Building the Spit

Once we’d decided on lamb next came design considerations for the actual spit. Whilst there’s no electricity on the island we were going to bring a generator: so I decide to build a spit that would rotate using an electric motor – and the heat would come from two fire pits on either side of the animal. After some head scratching I concluded the drive mechanism could be made out of a motor from an old washing machine – geared down to around 1rpm using bits of an old and dead bicycle. I ordered a 3cm thick piece of steel rod from local steel merchant and tapped threads for some threaded rod – this was to provide lateral support for the carcass whilst turning – otherwise it would have simply stayed put whilst the rod turned inside the beast. I’ll explain the contraption and its construction using the following set of pictures:

Spit Construction 1

This is at a fairly early stage of construction of the drive system. If you look carefully you’ll be able to spot how tolerant Mrs Scrumulous is of my projects, given this is our front room. The casing is  two pieces of half inch plywood, around 2X4′. They’re held together in a frame by threaded rod (easy to flat-pack – essential as we needed to transport it across to the island). The washing machine motor is held at the bottom again using threaded rod fed through the existing holes in the casing. The motor’s output has a wheel attached (runs around 1900rpm), to which a belt is attached which then spins the wheel which was from the main chamber of the washing machine. On the rod that this spins on is a smaller wheel (made from a spool from some welding wire):

Spool

 

Initially the spool (which powers the bicycle wheel using an old tyre as a belt) slipped, so it was lined with rough sanding paper.

Spit at Home

 

Here you can see how the existing cycle gears are used to gear down the speed further – as the large front gears are attached to the steel rod. This fits through a hole in the front and back of the casing, and is supported at the other end by a hole in a piece of 6X4 timber.

Spit with Rods

 

Here you can also see the threaded rods attached to the spit rod to stabilise the animal.

At this stage the spit was turning beautifully – but I had no idea as to whether or not it would take the weight of the animal without the motor giving up or the belts slipping. We didn’t have a lamb at hand – so I figured if it could spin me – it could spin a lamb. On I climbed and one of the guys flicked the switch – I now know what a rotisserie chicken feels like  – it worked like a dream. We were ready for the island.

Spit Roasting a Lamb

With much excitement we awaited the beast’s arrival – and watched as the small boat tendered it across the lake towards us:

The Lamb: Unadorned

The Lamb: Unadorned

It was beautiful, our first task was  to attach it to the spit:

Lamb Prep Pole

 

First, with some poking and prodding: insert the pole through the neck and out the anus.

Lamb PrepLamb Prep 5

 

Here the lateral rods are being inserted into the lamb, then threaded through the spit.

Lamb Prep 6

We tied the legs together for added stability. There’s something very satisfying about combining power tools and cookery.

Lamb with herbs

 

The last thing to do that night was stud the lamb all over with garlic and rosemary, rub with olive oil and then salt. We wrapped it in several layers of a clean cotton sheet and left it in an empty bath overnight. Saturday came and it was time to roast a lamb, here was our site:

Spit Site

 

And here with the spit set up and fire being prepared:

Spit Site pre-lamb

 

Here you can see we’ve stabilised the 6X4 with guy lines and used two pieces of sheet steel at either end of the spit, these both protect the wood and reflect heat back to the meat. The heat for a good roast should be, at the level where the meat will be, warm enough so that you can hold your hand there for 2-3 seconds – but no more. We used two pits so that we could put roasties (with half lemons and garlic) in pans below the lamb which collect the fat and make the best roasties ever.

Lamb Before Roasting

 

Here’s our beast – just before roasting.

Ben Spit Roasting

 

Here’s Benjamin tending the lamb, around 45 minutes after beginning – a lamb will take around 5-6 hours and should reach an internal temperature of around 60ºC.

Roasties!

 

Here’s the lamb a bit later, and then a few hours on, with the roast potatoes between the fires. These were par boiled for around 15 minutes first – then set under the lamb in roasting pans for about an hour.

The spit really worked fabulously, running at around 1.5 rpm for well over 5 hours. The only hitch was about half way through when it began to periodically speed up a bit – nothing too much to worry about but not ideal. I imagine it was something to do with the frequency of the alternating current from the generator – but I’m not an engineer so may be nothing to do with that. I noticed that gently applying pressure to the belts stabilised this for a while, so built a makeshift stabilising break which totally solved the problem:

Spit Break 1Spit Break 2

 

The pit break from two angles.

When the lamb was ready, we served it in pitta bread with a kind of mint raita, and the roast potatoes, and I think it was probably the best lamb I’ve ever had – though that might have partly been because we had just roast it ourselves on a beautiful island with some fabulous company – but I think it was pretty good lamb all the same.

Lamb ReadyReady to Serve

3 Replies

  1. Allison Moore Apr 28th 2016

    Excellent, will be trying this

  2. Patrick Jun 18th 2016

    The reason it started to speed up and slow down is probably because you were using the control panel from my old washing machine – it was probably doing it’s “rinse” cycle!


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