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Old 19 April 2023, 13:06   #1
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Country: UK - England
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Need a bit made

I need to get a pair of these made up in aluminium - it's a spacer plate for my exhaust. Roughly 120mm x 137mm x 50mm thick (Can be cut from 50mm plate, that'd do). Ideally black anodised, if possible, but I'll take what I can get!

Can anyone help, or put me in touch with a company that can? There don't seem to be many local machine shops around any more. I havd a dxf file of it.

Thank you.
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Old 19 April 2023, 13:31   #2
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Darren is my go to gut for things like this

https://www.dandcengineering.co.uk/?...CwW2c8axbBJqL4
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Old 19 April 2023, 13:39   #3
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Thank you - will get in touch with him. What's your surname and I'll let him know the referral was from you?
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Old 19 April 2023, 20:48   #4
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Quote:
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Thank you - will get in touch with him. What's your surname and I'll let him know the referral was from you?
Squirrell
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Old 29 April 2023, 21:24   #5
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Nobody would quote, let alone make them, so I cracked on and made them myself. Happy enough with how they came out.
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Old 29 April 2023, 23:33   #6
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Impressed, looks a nice job.
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Old 01 May 2023, 21:27   #7
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Quote:
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Nobody would quote, let alone make them, so I cracked on and made them myself. Happy enough with how they came out.
The cheat way of doing that would have been to have 5 x 10mm plates lasered A waterjet could have probably done it out of 50mm plate.

Nice job anyway
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Old 01 May 2023, 21:29   #8
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I fear that wouldn’t have ended well.
Main issue was I couldn’t find anyone prepared to do it.
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Old 01 May 2023, 22:08   #9
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The rest of the job was going quite well (pic1), until pic2.

a. How many amps do I need on the tig to join a bit of 12mm to a bit of 1.5mm. The lesson - 50 amps is too low, (didn't get enough penetration on the 12mm bit) 100 amps is too high - blew a hole in the 1.5, then.

b. In addition, I had a purge line set up to the inside. Which had fallen out! And therefore cooked the whole damn lot anyway.

So in to the bin that lot'll go and new stainless flanges (which I can easily get water/laser cut) are on order.

I quite like a bit of tig welding, but it takes time & practice.
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Old 17 May 2023, 22:44   #10
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So I cut apart that "bad" one I did and redid it:


Came out much better - practice.

However I then learnt that welding the outer cooling jacket on distorts the flange, despite it being 12mm thick. It's OK - but for the 2nd exhaust, I bolted it to a piece of plate:

This one came out perfect. I'll make a new one for the other side eventually.

And I also made up a tool for holding the "job":


And welded the AN-10 coolant inlets on:

Not forgetting to purge the inside as well when welding.

Also had to modify the actuator mounting brackets:


And it finally looked like it might all work OK:


So we're now at the stage of trial fitting it all to the boat. You can see the flanges came out OK:


And externally:


Which is where we are now. Next steps are to work out the routing and rigging for the air pump that runs it, along with take it all apart, give it a jolly good polish with my new 1.1kW bench polisher:


Still lots of jobs to do - fix the leak in the sump gasket, finish the new air intake scoop, but it's all good progress.
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Old 11 July 2023, 19:36   #11
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Done. Now it has operational switchable mufflers - just need to do a bit more work on the engine hatch to make sure that any water that goes down the scoop doesn't get injested into the engine and we can take it for a test run.

You can see the port engine water dump didn't get polished - neighbours got the hump with the noise.
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Old 30 July 2023, 17:33   #12
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Finally got a chance to test the new exhausts out yesterday, along with doing a bit of work on the fuel map. Bit choppy to do to much work on the map, but aside from that all the mods and upgrades worked well:





The main purpose of the test to see if the new exhaust system worked and the mufflers quietened things down a bit. A success in that regard, and in fact I think I can put a bit more water in to the mufflers to quieten them down even more - I might yet be able to make it marina friendly.

Was also good to give everything a check over after not running it for 2 years, and also manage to do some faster runs. Can't video those though as I was a bit busy, but quite enjoyed romping through some of the chop.




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