The Bucket Foundry

[Yow Ling]

Are you accusing me of using a decimal point Yow Ling ?

No , just commenting on the margin of safety that you allowed. Last time I checked decimal points were still legal

[Frits Overmars]

Last time I checked decimal points were still legal

Must have been some time ago .
You will be aware, of course, that mixing metric and imperial units and customs can have hilarious consequences, like losing an umpteen-million-dollar satellite before it could even reach orbit .

[Flettner]

The most useful tool for pattern making, nice new sand paper. About once every two years, yum.

[Flettner]

I win, water jacket in place. Not as easy as it looks, it's been a fight all the way and it still needs a little modification as the water jackets don't fit quite right.
A word of warning, don't use gum as a pattern wood, it's hard to work with, stringy, cracks easy and tough to sand. Stick to pine or macrocarpa.

[WilDun]

I win, water jacket in place. Not as easy as it looks, it's been a fight all the way and it still needs a little modification as the water jackets don't fit quite right.
A word of warning, don't use gum as a pattern wood, it's hard to work with, stringy, cracks easy and tough to sand. Stick to pine or macrocarpa.

So I guess that would apply to most hardwoods? I saved a few pieces from a plum? tree I cut up with the chainsaw at my son's place and put it under the bench to dry out. It was so bloody hard there were sparks coming off the chainsaw! I thought it might have been good for turning but having just looked at it, there appears to be a lot of cracking.

In your pictures, are three of those ports for inlets? and three for exhaust?

[Pursang]

I have had this 'alternative crank' verified by an 'off shore expert' and it seems it might be workable, certainly better than the epicycloid. Interestingly it also acts as a balance shaft and it's much easier to build with no internal gear. Epicycloid might shake a bit I think.

This is nicely balanced and would be relatively straight forward to build.



Depending on the pivot positions, link lengths and direction of rotation you could play with asymmetrical stroke rates & dwells.
The 'magical' primary reduction of the crank gears is pretty cool too.

Also, one of the linear bearing suppliers was offering ceramic coated, aluminium rod, tougher than anodise.

Cheers, Daryl.

"First they tell you you're wrong, and they can prove it.
Then they tell you you're right, but it's not important.
Then they tell you it is important, but they knew it all along."
Charles Kettering.

[WilDun]

This is nicely balanced and would be relatively straight forward to build.
Depending on the pivot positions, link lengths and direction of rotation you could play with asymmetrical stroke rates & dwells.
The 'magical' primary reduction of the crank gears is pretty cool too.

Also, one of the linear bearing suppliers was offering ceramic coated, aluminium rod, tougher than anodise.

Cheers, Daryl.

I like that one Daryl - got a lot of possibilities (and there are other ones too). Not so sure about the primary "reduction" though!!
Maybe that illustration is meant to be pump mode.

[Flettner]

So I guess that would apply to most hardwoods? I saved a few pieces from a plum? tree I cut up with the chainsaw at my son's place and put it under the bench to dry out. It was so bloody hard there were sparks coming off the chainsaw! I thought it might have been good for turning but having just looked at it, there appears to be a lot of cracking.

In your pictures, are three of those ports for inlets? and three for exhaust?

Three ports are inlet direct to the cylinder AND feed the 'under piston' (formally known as the crank case) at TDC, piston port. The other three you see are exhausts, under the exhausts (not easily seen) are three more boost ports, for want of a better description. These aim into the combustion chamber.

[Flettner]

I like that one Daryl - got a lot of possibilities (and there are other ones too). Not so sure about the primary "reduction" though!!
Maybe that illustration is meant to be pump mode.

Yes there must be dozens of layouts, but which one is best?
Yes my 'new system' I'm embarrassed to say was a dud. Off shore expert pulled me up on it, he was right. Never mind there are others.

[Drew]

This is nicely balanced and would be relatively straight forward to build.



Depending on the pivot positions, link lengths and direction of rotation you could play with asymmetrical stroke rates & dwells.
The 'magical' primary reduction of the crank gears is pretty cool too.

Also, one of the linear bearing suppliers was offering ceramic coated, aluminium rod, tougher than anodise.

Cheers, Daryl.

"First they tell you you're wrong, and they can prove it.
Then they tell you you're right, but it's not important.
Then they tell you it is important, but they knew it all along."
Charles Kettering.

Stopping the beam from bending would mean it need to be pretty heavy.

[husaberg]

Stopping the beam from bending would mean it need to be pretty heavy.

I don''t believe It needs to have a beam at all, imagine it, as being the skirt of a piston.

[Drew]

I don''t believe It needs to have a beam at all, image it, as being the skirt of a piston.

I was kinda thinking of just connecting both rods straight to the slug. Thrust forces cancel each other out, same result and a piece remobed from the puzzle.

[Ocean1]

Yes there must be dozens of layouts, but which one is best?
Yes my 'new system' I'm embarrassed to say was a dud. Off shore expert pulled me up on it, he was right. Never mind there are others.

If you could keep the mass down...

[Flettner]

I feel so pretty in my beads and all

[Pursang]

I feel so pretty in my beads and all

I had a girl friend who was quite partial to receiving a String of Pearls

Cheers, Daryl