Gus's Rupnow Hit and Miss Engine.

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It's all coming together really well Gus, don't push yourself too hard to get it done by the end of September, slow and steady wins the race.

Paul.
 
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You are doing a fine job Gus. That is going to be a good looking engine, and I'll bet it will run fine as well.

Cheers,

Tom
 
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Looking real good so far Gus. I'm slowly making progress with mine and I should have an update this weekend. I think you're already ahead of me.
 
Turned a bad day around into a productive day.
Bored Big End to fit ball bearing. The DIY Boring head earned its place on my PC Desk Shelf. The Makita BandSaw also. W/o which Gus would be half dead.
Been eyeing an Arbor Press but the poor man's press aka bench vice was a good substitute.
Piston and con-rod done.
See fotos.

Come next week. Will have flywheels done and piston will slide in Cylinder. Cast Iron F/wheels will be messy to machine.

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Brian Rupnow said:
You are making great progress Gus. You may end up with the third running Rupnow engine!!!---Brian
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OK ! Brian will try hard to be the third.:cool: In fact I sacrificed a deep sea trip Sept 2--3 as I just could not lose two good days cutting the flywheels. Plan to heat shrink shaft into f/wheel. Going for 1/2 thou interference fit. Is this good enough?? Plan to ream f/w hole and machine shaft end to fit.

Have done heat shrink fitting big compressor couplings to motor and compressor. 6" shaft. But couplings were USA factory bored.
Challenge is Gus to ream f/wheel and turn both shaft end.

Question, At TDC how much is the o/head and piston top clearance?.

After the f/wheel. The remaining jobs will be fun and challenging.

This time to cut pinion and wheel timing gear.
 
Gus--Nice to hear from you. For the flywheel to fit without slipping on the 3/8" shaft, you need a full .002" interference fit. Anything less than that, it will slip. If you are making a two piece flywheel, then I would have to know the two diameters involved. At top dead center, there is about .129" from top of piston to flat inside cylinder head. The valve heads stick up into that "clearance" about .045". ---Brian
 
Brian Rupnow said:
Gus--Nice to hear from you. For the flywheel to fit without slipping on the 3/8" shaft, you need a full .002" interference fit. Anything less than that, it will slip. If you are making a two piece flywheel, then I would have to know the two diameters involved. At top dead center, there is about .129" from top of piston to flat inside cylinder head. The valve heads stick up into that "clearance" about .045". ---Brian
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Hi Brian,

Thanks for the info. I am spot the TDC Clearance.

Will work on the Flywheel shortly.
 
Gus--That figure of .002" interference was for steel shafts being pressed into brass flywheels. I'm not terribly sure if it would be the same for steel shafts into cast iron flywheels or not.---Brian
 
Brian Rupnow said:
Gus--That figure of .002" interference was for steel shafts being pressed into brass flywheels. I'm not terribly sure if it would be the same for steel shafts into cast iron flywheels or not.---Brian
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Most of the motor pulleys we used for air compressors were fitted on to motor shaft with hydraulic press. Sometimes we drive fit with heavy hammers when for urgent jobs when hydraulic press is fully occuppied.

No worry will start from 2 though and see how it goes.
 
Sigh.:hDe:
Two days to machine two C.I.Pulleys. And too much excess metal to remove and overtaxing the mini Sakai Lathe and just turned 70 Gus.
Auto slide feed just packed shop. :wall:
Will try to free the lead screw tomorrow.

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Engine frame and flywheel assembly looks great.
bang-up, super
 
Going well Gus, I hate machining cast iron, the dust gets everywhere. If its humid where you are, that probably makes it worse.

Paul.
 
Sorry to hear the little lathe packed it in Gus, hope you are able to make an easy and swift fix.
So far, the work you have completed looks great, keep it up.

Eddie
 
Sorry about the lathe Gus, I machined cast iron for the first time last week, very messy, flywheels are looking good Gus, I will be in Singapore this weekend Gus, meeting my boat at Loyang, if I have time would you like to meet for coffee?

Dave
 
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