Author Topic: 30cc Flat Four (Puma)  (Read 2352 times)

Offline doubletop

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Re: 30cc Flat Four (Puma)
« Reply #45 on: July 09, 2019, 08:59:49 PM »
Interesting comment Brian, must admit I was in the camp that thought a very wee clearance was required before using loctite.  Do you have the loctite number for press fits, I will get some in!   :ThumbsUp:

Nice piston rods Pete.

Chris

Thanks Chris

Pete
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss

Offline doubletop

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Re: 30cc Flat Four (Puma)
« Reply #46 on: July 15, 2019, 10:22:19 AM »
Well I rolled the dice and, as I had a busy week ahead, decided not to start anything major. So did things like gudgeon pins, cam follower bushes etc. Then the bearings arrived so I was able to do the crank bearing holders.

That allowed a trial fit of the everything Iíve done so far.



This also allowed me to try out the timing belt sprockets. But that led to a bit of a disaster.



Drilling the crank sprocket to fit the 5mm stub on the end of the crank it fell apart (compare to the good one on the left)

Checking the supplierís catalogue and anything up to 16 teeth is a type 1 on the right are type 2 and they start at 18 teeth. So, it has to be a minimum of 18 teeth on the crank and 36 on the camshafts.

A bit of an update in the CAD and it looks feasible. The order will be placed tonight.



Youíll notice Iíve also included an alternative, simpler, exhaust pipe, the ľĒ x 32 spark plugs and a carb sourced from Hobby King.


Pete
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss

Offline doubletop

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Re: 30cc Flat Four (Puma)
« Reply #47 on: July 15, 2019, 10:43:59 AM »

A brief video of the trial fit. No pistons yet so it turns quite freely and the conrods can be heard rattling in the bores


Pete
?To achieve anything in this game, you must be prepared to dabble on the boundary of disaster.? - Stirling Moss