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ET: Engine (Twin) Chopped engine, reunited with original gearbox.

greg brillus

Well Known and Active Website User
VOC Member
Well this is a very scary topic.........has anyone done it, with any success. Or is the grief of trying to do it way over the top. The welding, massive distortion, not to mention the large chunks that are missing, cut off and thrown in the bin.........Does it remind you of when the Titanic broke up at the surface, basically split in two with large chunks spread out over the ocean floor........I am asking in all seriousness.......... Any comments or pictures of said repair would be great to see. Cheers............ Greg.

Bill Thomas

Well Known and Active Website User
VOC Member
After the first bit, I was going to stop watching !,
Glad I didn't !!,
A few things I didn't like, But who am I to judge.

A Must watch for anybody who wants to turn a Comet Into a Twin !!!!,
Only Joking, Honest.
Last edited:


Well Known and Active Website User
VOC Member
Further to the Bob Dunn weld job, I remember seeing it partially welded in his workshop around 2008. Later, in 2012 - on another visit - I saw the engine in the process of re-assembly and snapped a quick photo. Why it had a layer of what looks like sealant sealant covering the weld I can only guess...(?).

Either way, it was a remarkable feat of endurance on Bob's part.

Peter B


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Bill Thomas

Well Known and Active Website User
VOC Member
I wonder if it's still being ridden ?,
Big Job .

Before Bob did Alloy welding, I took my cases to Dave Lindsey, They worked together,
And Dave took me to His friend for the Alloy welding on my gearbox,
Great Gobs of Weld, Always worried about a bit coming off and going into the gears !!,
But that was over 40 years ago, So I think I should start worrying about something else !.


Well Known and Active Website User
VOC Member
I have no direct experience but have heard good things about using the new generation of handheld laser welders which seem to allow even novice fabricators produce high quality joins . The advantage for Aluminium is supposedly a clean and fast weld with a very small and limited heat affected zone and depending on the head used a wide "wobble"bead can be produced . A1500 Watt machine is ( I am told) capable of producing a weld depth of up to 10mm in aluminium. Maybe a local search to see who has appropriate equipment and experience would be worthwhile but I understand the reluctance to commit as you will only get one chance and it must be right first time.
I use a laser firm close to me, you also need a deep pocket. With the machines costing upwards of £100,000.00 the need to recoup that outlay has to be factored in. The CNC rotary fullt automatic, cast £500,000.00.

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