123x58 aluminum boat ongoing project

Been 12 year since I have pulled up a boat, this project takes a 2nd seat to real work…

Uploading: 20210928_090506.jpg…


I should also add I had to index both the bottom sheets and the sides, my table is 48x96 and the sides cuts were roughly 132 long. Also this will get a 130hp 2stroke seadoo engine and jet. Thinking it will be about 600lbs dry and hoping it will do 55mph


Whoa! That’s Awesome!

Oh come ON! How on earth am I supposed to feel good about myself after seeing that?


Looks awesome! I’m curious what the process of waterproofing aluminum joints looks like. Is it simply a sealant fillet like on wooden boats or is there a mechanical component like rivets required?

It will be a welded hull


Is this boat similar to the Jetstream boats?

Yes, close in size and power. However, I designed this one. Also the first time I have don’t from cad with cnc cut parts…

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Get yourself some shockwave seats in there to save your back while you’re at it!

Ouple more progress pics, I need a couple more good days to complete fabrication on the hull before I shelf for a bit and qork on some actual pending jobs!


Bit by bit, getting there!!


Looked into them, way to pricey for this build!

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Few more progress pics. Hope to have her flipped after tomorrow for bottom welding and hope to have donor jetski by the weekend. I should really look into checking cylinder compression though. Any guidance with this would b greatly appreciated! The jetski does come with a spare engine, so I hope I can piece together a working set up without spending too much at the machine shop… I will also most likely design and fabricate a aluminum intake tube to avoid flanging and using the one out of the jetski… need the jetski at this point


WOW… Project of the century! Definitely following!

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I have had a few ski’s what are you looking to figure out?

Off the top of my head, test cold, Wide open throttle, redo the top end when it gets low (quick cheap and easy)…or you will end up buying a new one or a total rebuild (expensive, no fun).

Like no idea how to lol, I should prob do some research…

Oh, sorry. I use something like one of these, https://amzn.to/3ks8QXx, you can rent one from a auto parts store usually. Take the lanyard out of the ski, as well as both spark plugs. Put the tester in one barrel, hold the throttle wide open to let all the air in, and crank it until the needle stops moving. Reset and try the other side.

You can look up the specs for your motor to see where it should be. Typically between 150-180 (for the two strokes), the biggest thing to watch for is the cylinders should be very even more than 5 psi difference and you need to get a new top end asap. I have never seen one more than like 3psi difference.

The spark plug caps typically have a grounding post nearby they fit on to save your ECU, for when you do this, use them. They look like fake flat spark plugs. When you unplug a spark plug they get plugged into the post, (or a cylinder head bolt depending on the ski). never hang them

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You don’t like random sparks in a potentially fuel-filled ski hull while cranking an engine over? :slight_smile:

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Thanx for the info, obviously you can’t crank over by hand? I believe the donor I’m looking is in need of a starter

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