Duesenberg Straight 4, quarter scale

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its the little things that take so much time...
here are the distributor and oil pump, still works in progress
(and there's a water pump part currently clamped to my mill,
which is taking up lots of mental energy to design)


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a small amount of progress on the water pump (have mostly been working on other projects)
some (fun for me!) rotary table work was involved, plus lots of filing afterwards


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some machining operations on the rotary table for the water pump scroll
first is approximating the scroll height as a staircase
second is using a 45-degree end mill to approximate the tubular roundness of the scroll


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speaking of "small parts", I recently ground the pair of cam shafts

(am very pleased with the results I got switching to a CBN wheel
but not sure how to dress the wheel once that is needed)



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perfection is the enemy of git-er-done, this doesn't look great, but will be functional and well hidden inside the water pump
mostly machined on a tilting rotary indexer, with a little bit of dremel work afterward
the entry and exit blade angles are wrong for a water pump, but won't make much difference for an engine that only gets run for short periods of time for demonstrations (a similar water pump on my Merlin V-12 blew a plastic hose off its fitting, so "good enough for government work" !)


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water pump housing needs inlet pipe
if you have a mill vise you're at the start of a long journey of collecting necessary clamping fixtures and devices :) !!!


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I didn't photo the machining of the flywheel/clutch housing, but here it is, mostly finished. basically it was a lot of rotary table work. now the engine has mounting lugs and I can start on a traditional oak wood box base to mount it on. It has a boss for a starter motor as per full size, but I don't see how to actually get a one-way-roller-bearing in there so that might be cosmetic, and starting might be via a electric drill on the crankshaft.


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Can you put the one way bearing on the crank instead of the the starter?? Better anyway because the belt/chain stops when the engine starts.
normally that would work but with the Duesey there's a ring gear that's cut directly into the flywheel. I guess I could make the ring gear separate, and if I wanted to be clever then use a one-way mechanism to engage it with the flywheel (like pawls and ratchet in a ten-speed hub, those tend to be noisy but with the engine running I doubt you'd be able to hear the ratchets), so maybe that was a good suggestion after all!

the other idea I have in mind is a transmission to bolt onto the flywheel/clutch housing and put the starter motor inside the transmission !


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Separate the gear and flywheel. The gear holds the one way clutch and rotates on the crank. The flywheel is attached firmly to the crank?

that's a good suggestion, but the ring gear should be between the crankshaft and the flywheel, and the flywheel bolts onto a large flange machined on the end of the crankshaft so no way to get the roller bearing in there (without designing a new crankshaft, argh!) that I can see
Peter the engine is looking good and the cam shaft grinder works very well.
Is there any information on making the cam shaft grinder

there was a fellow BAEM Club member that was going to turn my camshaft grinder drawings into something readable and/or usable by other people but that hasn't happened yet, and I can't say when I'd be able to get around to it, perhaps I can answer some questions ?

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