Zee Needs Popcorn

[Tennessee Whiskey]

I’d put that next to the jar of cocktail onions and look at it the rest of the night     Damn nice Zee

Eric

[jonesie]

zee that looks really good  keep up the good work,looking forward to seeing it run,sure you are also.

[Kim]

Wow!  That's a challenging part for sure.   There's a lot less metal on it when you finished up!
Kim

[Steamer5]

Hi Zee,
 You nailed that! Hope Mrs Zee wasn't to put out with you being preoccupied all evening!

As a thought now you have thinned down both sides & exposed that internal corner, could you set it up & with the correct sized end mill take out the square corner? Totally understand if you are more than happy with what you have!!

Right more  needed......spring better hurry up!

Cheers Kerrin

[zeeprogrammer]

Thanks everyone. I felt pretty good about it.

As a thought now you have thinned down both sides & exposed that internal corner, could you set it up & with the correct sized end mill take out the square corner?

It's tempting. My biggest fear is the dreaded thought "only one more operation and it's done" jinx. I'm also not sure how to hold it in the lathe without crushing it.
So, yes, I'm happy with what I have. 

[zeeprogrammer]

Disaster.

See that hole under the cylinder cover? Fooey.
Dumb mistake. When I made the cylinder, the plans appeared to show that hole drilled perpendicularly to the bore to a port.
I had used an end mill to make the port but worried that it wasn't deep enough.
So I moved the hole a little out thinking the cover would still cover it...dumb.
When I made that hole, the ol' little voice in my head said, "Odd. For past cylinders I had drilled that hole at an angle."
Looking at Stew's article I saw that he had drilled the hole at an angle. Sigh.

Make cover bigger? Nah. It would look weird.

I'll remake the cylinder. If you all recall...the cylinder was damaged anyway by a previous boo-boo.

That will bring me to cylinder #3.
Wish me luck.
A 3rd failure typically makes me question why I bother. 

[Jo]

That will bring me to cylinder #3.
Wish me luck.
A 3rd failure typically makes me question why I bother. 

But are you enjoying yourself ? Just think how much experience you are getting, you couldn't have tackled something this difficult only a few years ago.

And what would life be like if we didn't find ourselves new challenges to try to over come? Its the journey that matters 

Jo

[zeeprogrammer]

That will bring me to cylinder #3.
Wish me luck.
A 3rd failure typically makes me question why I bother. 

But are you enjoying yourself ? Yep Just think how much experience you are getting, you couldn't have tackled something this difficult only a few years ago. True

And what would life be like if we didn't find ourselves new challenges to try to over come? Bored Its the journey that matters  Okay. Okay. I'll come out of my hole. It didn't hurt to have done that crosshead guide just before. 

[Tennessee Whiskey]

As I’ve said before; first one is the prototype, second one is for the revisions, third is the finished part. Or, just figure you’re helping our fledgling steel industry  .. Personally, as long as I’m making chips, I’m happy and never really count the “prototypes” .

Er

Eric

[Johnmcc69]

Can you drill/tap & plug the hole & re-machine it?
 It's coming along nicely Zee...Keep at it.

John

[Jim Nic]

Zee
The inlet port is supposed to be drilled parallel to the cylinder bore.  From Stew's original metric drawings the cylinder end cover at radius 28mm is supposed to be larger than the rounded part of the cylinder, which is radius 24mm, and so will cover the port.  On my model the edge of the cover is level with the flat base of the cylinder block.  It would appear from your picture that your cylinder end cover is too small enough and if you made that part bigger it may save you making a new cylinder block.

Jim

[JC54]

I can understand your pain/frustration on 3rd attempt at a part, I have finally got my first engine ( a simple wobbler) running after 5 attempts at the piston . I think the knack is to learn from your mistakes, and as you do, ask questions.... The expertise on this site is so amazing and freely given..    John

[propforward]

A 3rd failure typically makes me question why I bother. 

I go through that, but on the whole it's a lot of fun, which I think is the reason for bothering. Also, it just goes to show that this is NOT an easy hobby. It tasks the ol' brainbox, which is a good thing.

[b.lindsey]

Think of it this way Zee. The world population is currently around 7.6 billion. Even if there are a million of us worldwide that enjoy making engines that works out to .00013 or just over 1 in 10000. You are a part of a somewhat rare and sadly dwindling fraternity.

Bill

[zeeprogrammer]

Thanks everyone.
Not to worry. 

@John: re drill/tap & plug...I would have my doubts. The part of the hole that is covered has a passage to the bore and I think it would be messy to plug. I'm not sure as I've rarely done such a thing. Besides I wasn't really happy with the cylinder due to the damage I'd caused when milling the outer curve so this is a nice excuse to push me to remake the cylinder.

The inlet port is supposed to be drilled parallel to the cylinder bore.  From Stew's original metric drawings the cylinder end cover at radius 28mm is supposed to be larger than the rounded part of the cylinder, which is radius 24mm, and so will cover the port.  On my model the edge of the cover is level with the flat base of the cylinder block.  It would appear from your picture that your cylinder end cover is too small enough and if you made that part bigger it may save you making a new cylinder block.

Good to know I hadn't misread the drawing. Does make me wonder why Stew drilled at an angle. My cylinder cover is 1 3/32 (28mm-ish) and the cylinder is 15/16 (24mm-ish).
The problem was I'd moved the hole out a little. I was hoping it would still be covered but I'd measured incorrectly and moved too far. The reason I moved the hole was because the end mills I used to make the ports are a little short. Drilling the hole where it belonged wouldn't have touched the ports. I could make the covers still larger but I don't think I'd like the look.

I suppose another possibility is to not use an end-mill for the ports and instead chain drill with a 1/16" bit. But that seems like I'd be asking to bust a bit.

@Bill: 1 in 10000 eh? I was always told I was 1 in a million.