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D2 - Fuel and Exhausts Everything to do with getting fuel into the engine, and fumes back out again

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  #1  
Old 17th February 2020, 08:40 PM
MikkiJayne MikkiJayne is offline
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Default Exhaust tinkering

The D2 S8 has a donut-joint between the passenger side downpipe and cat, to allow the cat to be removed for access to the gearbox. Unfortunately most of them are looking pretty crusty by now, this one particularly so!



This is beyond salvation, and obviously unobtanium now - Prestige don't have any, and I don't have any good ones so time for a new solution.

Start with a 3D printed prototype to test fitment



That fitted the pipe quite well, so I sent the file to the local steel stockholder who CNC plasma cut me some flanges (minus small holes as the plasma won't cut them)



Drill mounting holes



Then stick it in the lathe and turn a chamfer in to one face to match the pipe



and then cut the lovely thing in half



Alas, this is the only way to get it on to the pipe.

Using the other flange, I bolted it all together to get it straight while back on the pipe. The pipe is covered in anti-spatter spray and I also used some aluminium foil between the new flange and the pipe so I didn't weld them both together.



Then attacked it with the mig, and we have this





I think this should work just fine, and I went slightly overkill and made it from 10mm plate, so it should last a few more years I need to do the same again to the cat which has the other side of this tomorrow, and then hopefully it will all bolt back together nicely
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  #2  
Old 17th February 2020, 09:55 PM
Davey Blueeyes Davey Blueeyes is offline
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Flipping Nora. Wouldn't the world be a better place if MJ was in charge of it?!

Honestly, I think you are about five years away from restarting complete D2 production from Devon.

If you do I'll have one
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Old 18th February 2020, 07:47 AM
Sit down, Waldo Sit down, Waldo is offline
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There are so many threads on here that make me think 'What have I done?'

Are you really attached to your day job MJ?
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Old 18th February 2020, 05:26 PM
MikkiJayne MikkiJayne is offline
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Quote:
Originally Posted by Sit down, Waldo View Post
There are so many threads on here that make me think 'What have I done?'
#D2Life I plan to drive my D2 until the dinosaur squeezings run out, and I'll take as many others along for the ride as possible

Quote:
Originally Posted by Sit down, Waldo
Are you really attached to your day job MJ?
I hate it, but it pays the bills and means that D2s can still be fun. If I did them full time, it would stop being fun

Finished this off just now. The second piece was much easier having learned a few things on the first. We end up with this:







Pretty happy with that, although yes, 10mm plate was slightly overkill 8mm next time, and make the centre hole a bit larger too.
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Old 18th February 2020, 06:32 PM
gninnam gninnam is offline
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Very cool
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Old 18th February 2020, 08:53 PM
Sit down, Waldo Sit down, Waldo is offline
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Quote:
Originally Posted by MikkiJayne View Post
#D2Life I plan to drive my D2 until the dinosaur squeezings run out, and I'll take as many others along for the ride as possible
I plan to drive mine eventually
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Old 19th February 2020, 11:17 AM
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Dezzy Dezzy is offline
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Hey you.


You should have said, think I have some more somewhere, I had them lasered, with the small holes
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Old 19th February 2020, 11:30 AM
MikkiJayne MikkiJayne is offline
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I didn't want to draw your attention to the quality of my welding

The next batch I will get done with either a better plasma or a laser, but that has to go up to Tivvy and takes a few days. These were done by Conibeare's same-day so I couldn't be picky
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Old 19th February 2020, 03:16 PM
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Quote:
Originally Posted by MikkiJayne View Post
I didn't want to draw your attention to the quality of my welding

The next batch I will get done with either a better plasma or a laser, but that has to go up to Tivvy and takes a few days. These were done by Conibeare's same-day so I couldn't be picky
They're tough to weld and make it look pretty. Think the ones I had cut were 6 or 8 thk so didn't need the edge prep.

I've not had much luck with laser people, getting back is too much trouble, getting it done in the next week is to much trouble, unfortunately cant go stand next to the operator and give him sweets till it's done anymore.

Mirror polished Stainless next time
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Old 19th February 2020, 03:50 PM
HPsauce HPsauce is offline
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I was putting my 3D brain into action and trying to think of another way of solving that without welding.....

Could you make each flange out of a pair of interlocking U-shaped pieces that slot onto the pipe, one from each side, maybe about 4mm thick? It should all pull together nicely once the bolts are fitted, though may need some clips (or just adhesive) to hold together while fixing?

I know a simple version as in my sketch won't apply pressure all round, that would need a protrusion on the second plate which might be tricky to make.
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Last edited by HPsauce; 19th February 2020 at 04:07 PM.
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