PMR 7 Twin Cylinder Steam Engine

[zeeprogrammer]

Thanks guys.

I need a little  here.
I need to do a 45 degree chamfer on the eccentrics. I cannot figure out how to set the cutter to achieve that.
It seems to me that I need to rotate the tool post itself, not just the compound.
In rotating the compound only, I can't seem to figure out how to set a cutter to get the path needed. I typically run out of Y travel.

But that nut on top of the tool post doesn't seem to want to let go.
It should...shouldn't it?
If you look closely...you'll see a gap just below the nut in the picture. There's another one on the other side.
Is that significant for loosening this up?

Is it just a matter of not giving enough oomph?

For the eagle eyed...pay no attention to that red thing. It's a 3D printed spider and not working very well.

Can you believe it? This is the last part I need to machine. 

I had a pretty good scare earlier this evening. It looked like the piston rod wasn't on the same line as the crosshead.
Whew...I think it's okay. But if it's not...then this project is toast. Or rather...a door stop.

[crueby]

Don't know how your toolpost attaches, but alternative is to just file the bevel while it is spinning. Carefully. Unless the chamfer is a critical dimension.

[b.lindsey]

That nut should free up the toolpost to swivel Zee unless there is a spanner that fits those slots you mentioned. Have you moved it since you bought the machine? No more chamfer than you need on those rings, you can probably just plunge in once you get the cutter set to 45 degrees. It won't take much at all and is mainly cosmetic.

Bill

[zeeprogrammer]

Thanks.

@Chris...I was thinking about filing. Both sides have to be beveled and I worry whether my hand skills can match them.

@Bill. I haven't touched the tool post itself since I got the machine. Obviously there's a way to remove it but I don't know enough to know whether it's just the nut (and it's really tight for some reason) or if I need to do something in addition to the nut to get it loose.

[crueby]

Did they make the nut a left hand thread by chance?


Or is the toolpost bolted from underneath the cross slide?


I know you are a software engineer, but there should be an instruction book?   

[zeeprogrammer]

Did they make the nut a left hand thread by chance?


Or is the toolpost bolted from underneath the cross slide?


I know you are a software engineer, but there should be an instruction book?   

Hm...instruction book. Didn't come with but I hadn't looked on the internet. Lemme find the model number.

[b.lindsey]

I can't imagine having to bolt it from the underside. If you can't find any info on the internet, give them a call and ask them. My bet is on an overly tightened nut, but best to find out before messing something up for sure. curious as to what the answer will be so please let us know.

Bill

[zeeprogrammer]

I got it off. Turns out it was just really really tight.

The odd thing is...searching around the net...I could not find instructions for installing or removing this particular model.
The main difference being that 'ring' below the nut with the two gaps. I didn't see anything similar.

But oh well...I should be okay to continue.

[b.lindsey]

Great,  now you know  Thanks for the update.

Bill

[zeeprogrammer]

And so with the help of a great educator and a great elf...I got a chamfer.

  Getting there!

[crueby]

YeeHah!


 

[b.lindsey]

So all the parts are done now....great!!!  Just the touch up stuff and assembly to go and you will have a fine runner I am sure, and it hasn't even been a month yet  . I am going to need to up my game 

Bill

[zeeprogrammer]

So all the parts are done now....great!!!

Not so fast my friend. 

I needed to finish the eccentrics.

1st pic shows boring.
2nd pic shows ensuring the eccentric hub fits.
3rd pic shows the eccentrics done. Oops.  Not so fast my self. I still need to drill/tap the hole for the eccentric rod.

I also need to make the pistons again. The rings just don't fit well enough. 

[crueby]

Nice job on the eccentric followers. On that model the rods go through into the slot in the eccentric cams, right?

 

[zeeprogrammer]

Nice job on the eccentric followers. On that model the rods go through into the slot in the eccentric cams, right?

Yep. But only if I remember to drill/tap the holes.