Gus's Rupnow Hit and Miss Engine.

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Looking very nice Gus. I'm putting off the sideplates for fear of lining the bearings up properly, but I'll soon have no choice.
 
hi Gus.
What are you doing? Several days.
_______________________________
Jonny.
 
hi Gus.
What will you do tomorrow?
i'll be watching and waiting.
__________________

Jonny.
 
Great work Gus.....The sparplug is already inside & ready too make Sparks.
Can you make some pictures from how you machined the cilinder. The inside interested me very well.
 
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So how was the fishing Gus, fillets, steaks, or fillet steaks?

The build is looking good, measure twice and cut once is a good philosophy. When you can take the time, why not take it. Of course we are all grinding our teeth, waiting for the next part to the puzzle, so no rush ;).

Eddie
 
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C.I. Bar was surplus from Webster Engine built.
1.Had to carefully plan work/turning process to avoid scrapping.
2.Cut blank bar to diameter and shape.
3.Cut fins. Cross-slide and blue scribed line is my Poor Man's DRO.
4.Cylinder finned and done except for final boring to print I.D.Will leave the final boring
to tomorrow.
Gus is making some headway step by step.:hDe:

See fotos

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IMG_2240.jpg
 
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Unbored Aircooled Cylinder drilled/tapped and mounted on engine frame. Spark Plug put in for showmanship.
I have another 4 weeks to go to finish and run w/o the hitting & missing.
Will take my sweet time to boring to print I.D. and spot on with Holtest Inside Micrometer
to "0"

IMG_2242.jpg
 
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Very nice, gus. It's fun to watch you work.
Regards
________________________________
Jonny.
 
ELM6061 said:
So how was the fishing Gus, fillets, steaks, or fillet steaks?

The build is looking good, measure twice and cut once is a good philosophy. When you can take the time, why not take it. Of course we are all grinding our teeth, waiting for the next part to the puzzle, so no rush ;).

Eddie
Click to expand...

Hi Eddie,

Bad luck struck me for two days.
Two hits on Saturday and two on Sunday. Hit snag and broke off.
Sunday mate landed a 2 pounder for dinner at the Marina.

This coming weekend's tidal current too weak so its housekeeping on the boat.
 
Swifty said:
Going great Gus, once you have the cylinder and piston finished most of the hard work is done.

Paul.
Click to expand...

Hi Paul,

Thanks for the support. Still have the con-rod big end bearing fit to work on.
Having successfully bored the side plate to fit main bearing gives me some confidence to bore con-rod. The flywheel bored to shrink fit main shaft is another challenge with my limited machine tools. Having a "Warner USA''
Boring sure helps to do a good boring job. Boring to shrink fit will be dicey.That will be next week.Have done shrink fitting during my heavy air compressor erection days.
The piston is not too much different from Webster and so should not be a problem.
Now enjoying the assembled frame and cylinder and dummy shaft with main bearings fitted on.
 
Welcome back and the progress is looking great Gus.

Bad luck on the fishing, but as we all know; That's Fishing!!!! Mate if I ever win Tattsloto, I am going to come over and charter you for a run out, even if I cannot hold one of those groper myself, I sure would enjoy watching (heck, I will even bring Swifty if he is up for it. Bit deep for the fly rod though ;).).

Eddie
 
This engine is going to be beautiful,
That is nothing short of amazing.
_________________________
Jonny.
 
Air Cooled Cylinder bored but 2 thou oversize.).875"------0.877.:hDe:
Piston is a borderline save or reject. :wall:
The roughing mill under-tightened and drawn in to take a deeper cut with made slot hole pit deeper by 4 mm. Will decide to save or cut new piston.New piston will take a half day work.

IMG_2248.jpg
 
Terrific engine!
i'll be watching and waiting.
_________________________________
Jonny.
 
Gus--If the piston is .002" undersized, it will still probably be okay. I always bore the cylinder, then hone and lap it before I make the piston. Then I TRY to make the piston .001 undersize. Its pretty subjective, trying to measure or machine anything to within .001"---for me anyways. If the machined finish of the piston measures .002 undersize, I would still carry through with the procedure of lapping the piston into the cylinder as outlined in my build thread. In reality, very little of the piston rides on the cylinder wall anyways. Up near the area where the piston ring is, you get virtually zero contact, because the piston ring takes all the contact and holds the piston concentric in the cylinder bore. The maximum contact area with the cylinder wall is down at the far end of the piston skirt, and that doesn't seal much of anything---it just serves to keep the piston from tilting in the bore.---Brian
 
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wow, nice work gus! ill be looking forward on following your build.
 
Brian Rupnow said:
Gus--If the piston is .002" undersized, it will still probably be okay. I always bore the cylinder, then hone and lap it before I make the piston. Then I TRY to make the piston .001 undersize. Its pretty subjective, trying to measure or machine anything to within .001"---for me anyways. If the machined finish of the piston measures .002 undersize, I would still carry through with the procedure of lapping the piston into the cylinder as outlined in my build thread. In reality, very little of the piston rides on the cylinder wall anyways. Up near the area where the piston ring is, you get virtually zero contact, because the piston ring takes all the contact and holds the piston concentric in the cylinder bore. The maximum contact area with the cylinder wall is down at the far end of the piston skirt, and that doesn't seal much of anything---it just serves to keep the piston from tilting in the bore.---Brian
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Hi Brian,

Thanks for the expert advice.

Looking forward to spin this engine by End Sept. I have gone for Viton O-Ring since I have the #400 lapping compound. The Nielsen Honing
Tool was very handy to remove the rough surface. Will make a honing bar for the fine honing to take the Viton O-Ring.

Bought a "Made in China"---6" Starrett Digital Height Gage for your next engine build. H.Gage came in a spiffy looking Aluminium Case.
Cost me a bomb but no worries made some $$$ to cover up.

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she is really looking good.
______________________
Jonny.
 
Been another productive day. Completed new piston and rough honed cylinder to fit .:cool:

Con-Rod blank marked out. No fishing tomorrow since the tidal current is too dead slow.

Will try hard to cut a good looking con-rod tomorrow. Again the Poor Man's B.Head will be called upon to bore big end to fit bearing. The big end profile will require some milling with
my DIY Rotary Table.

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