I can weld Ali but do not have the equipment, I used to do it at work when I worked for an engineering company.
The equipment is now available at a reasonable price but you require argon gas and that can be difficult for hobbyists

I have a ali, jet boat made by Jettec, a company here in NZ, who make full size jet boats. Mine is the lesser known model about 1/8 scale. The more common size was 1/4 scale powered by 2 stroke motors. ( there is a electric powered version used by the canterbury university, for water studies, but that's another story)
My 1/8 scale is almost to heavy with brushless motor, ESC, LIPO batteries.
Would be better to use a small glow motor, but where I sometimes use it, not allowed to use IC motors.

I've had in mind for a number of years to put together an aluminium jet boat. The type of thing they use in the rapids. The thing that stopped me is welding aluminium together. I'm told it's quite difficult. Cutting the shapes from aluminium shouldn't be a problem and also bending the parts. It's just tacking, welding the sheets.

Hi Chris
If you do we may be able to meet face to face
👍

Hi Ed - some months ago unfortunately! I may go Thursday though now that it is warming up!

Chris

Alessandro, Here is a picture of the drive

Hi Chris
No it’s one I bought from Temu and does not have a bucket reverse
When last were you down at the club
Ed

Reminds me I must start building my water-jet project but I'm trying to be good and finishing off some of my earlier builds first or at least progressing them. I've already printed off the drawings (yesterday) for my outboard project even though I've only just recently completed the drawings for that and it should be the last to be built. 😁

Ed - is yours a TFL water-jet? If so I bought the 29mm version so if so yours will be a bit of a beast!

Chris

Hi all I have a never used large brushed electric water-jet drive with bucket reverse toothed belt driven.
It belongs to club and I am looking for a buyer. It is a Rip Max model they had on sale for £160. £60 and it is 'yours'.
P.M. me if interested.
Roy

January 2024 ModelBoats Magazine has plans for modern landing craft

I have the issue some place, I'm not sure if it was twin jet or single. I can find it out and have a peek at the plan, I'm sure you should be able to acquire a copy

https://www.modelboats.co.uk/117106/january-2024/

Hi EdW, isn't there a photo?