Thank you Tree Monkey

[LegDeLimber]

In theory the cam action would work. I'm not sure how well it will hold in a thin section of aluminum like a piston dome though.
I would be a bit leery of depending on it myself.

If you're using steel for the mandrel, then about an inch deep of thread and screw would probably give decent service.

Are you thinking of being able to use it in more than one bore size?
Thus needing the adjustment.

 

[czar800]

In theory the cam action would work. I'm not sure how well it will hold in a thin section of aluminum like a piston dome though.
If you're using steel for the mandrel, then about an inch deep of thread and screw would probably give decent service.

Are you thinking of being able to use it in more than one bore size?
Thus needing the adjustment.

Not necessarily thinking of different bore sizes, but more of just real fine adjustment. That's a hard hole to drill just right. That's why I think if you made the bolt head shap a little bit of a cam lobe then you could fine-tune then final tighten everything.

 

[czar800]

This is not exactly what I'm talking about, but shows the concept. I grind bolt heads or screwheads in a Camloop shape often to move things very small increments.

 

[bikemike]

Poor folks have poor ways. View attachment 401558

At first I thought that was a poor man's pop up piston until I seen the tool steel

 

[LegDeLimber]

Poor mans pop up? I think I recall a couple of us wondering about a few ideas like that.
We need a volunteer to build one. I want to see the solid/upset rivet one , myself!

Then the cam screw: Yeah, i figure try to get the notch in the cutter/file piece,
so as to be close as you can to the bore size.
then the cam screw probably would be good if you took it off to about the shank diam
then swept out to the full head diam. Might not even need that much range.
Just have to build it and see how all of the geometry of your hole patterns vs part diameter work out.

 

[drf255]

I'll be 100% honest, I don't quite know what you mean. Full disclosure I'm a complete hack and have never ported a cylinder in my life. But I figure if I'm going to try I may as well figure out how to cut a squish band manually. If it's good enough for tree monkey it can't be all that bad, right? I did play around with the "cutter" today after work...I put the piston in the cylinder upside down and moved the cutter over so it barely touched the cylinder wall then snugged it down. Rigged it up in the vise using a nut and a socket and here's what I got...
View attachment 476788

Seems to have taken the ridge off. Next up...accurately trying to lower the base with no lathe and figuring out a good place to start with timing numbers...

Is @wcorey selling his adjustable mandrels yet

What's the squish at and what cylinder is that? What mm diameter?

Sometimes if you elimate the base gasket, you won't need to cut the base.

 

[big t double]

What's the squish at and what cylinder is that? What mm diameter?

Sometimes if you elimate the base gasket, you won't need to cut the base.

It's a 460 cylinder going on an 044. It was a head slapper with no gasket...untill I sandblasted the carbon off the band. I didn't check the squish after that. Should've....but didn't. I need softer solder...or that plastigauge stuff.

 

[Macman125]

This thread peaked my interest. I had to try it out. It works quite well surprisingly.

 

[big t double]

View attachment 476856

This thread peaked my interest. I had to try it out. It works quite well surprisingly.

nice...pics of the squish band you cut with it? .... and I like the saying under your name...im still trying to get time to read rothbards man, economy and state w/ power and market...dam its a huge book. sometimes ill listen to the audio books on my way to work that are up on mises.

 

[Macman125]

Rothbard makes for some good reads. Also ludwig von misses, Ayn Rand, Stephen Molyneaux, George Orwell, Lysander Spooner. If you have the time find the book: Behold A Pale Horse by Milton William Cooper. As for the cyl pic here it is. The flash kind of screws with the detail though. I ended up shaving the band down till it was flush with the start of the taper.