Opposed 4 Compressed Air

[Deanofid]

Chuck, how'd you get the rods on the pins? Crank pins come out of the throws?

I vaguely remember this engine from when I first joined here. I went through the WIP's of older projects, picking out titles that sounded interesting. Still haven't seen them all. There are a lot!

Glad you're back on this one.

Dean

 

[NickG]

Chuck,

Seeing that crankcase has just reminded me I saw this from the start!

Wow, don't you need a rest after the i.c. engine! Obviously not!

Good going.

Nick

 

[cfellows]

Chuck,

Seeing that crankcase has just reminded me I saw this from the start!

Wow, don't you need a rest after the i.c. engine! Obviously not!

Nick, it's like Metal Butcher says, "If I don't keep busy, I'm afraid I'll roll to a complete stop!"

Chuck, how'd you get the rods on the pins? Crank pins come out of the throws?
...

The crank pins are silver soldered into the outer crank webs. Setscrews hold the crankpins in the thick, center web. It did it this way to simplify the connecting rods.

Thanks for the words of encouragement.

Chuck

 

[ariz]

very nice engine chuck!!!

but I can't understand how the crankshaft and connecting rods may enter in the crankcase... :-[
how do you do?

 

[cfellows]

very nice engine chuck!!!

but I can't understand how the crankshaft and connecting rods may enter in the crankcase... :-[
how do you do?

Good Question! I had planned to assemble the crankshaft inside the crankcase, but just discovered that it ain't going to work without some modification. I'm going to have to bore the hole at the back end of the cylinder larger so the crank can be inserted from both ends. I had originally planned to insert it piece by piece through one end but I can't get the back 2 rods over the crankpin that way. Nice catch!

Chuck

 

[cfellows]

Well, ariz, took a little wind out of my sails, but I'll get it fixed. In the meantime, I spiffied up the connecting rods.

Chuck

 

[NickG]

Really nice rods chuck, were they finished with a file or rotary table?

NIck

 

[Powder keg]

Looking good there Chuck!!! I want to start my Con rods this weekend. We'll see how things go.

 

[cfellows]

Really nice rods chuck, were they finished with a file or rotary table?

NIck

I have a small rotary table which fits in my milling vise that I used. It's not a geared rotary table, but rather swings with a handle that inserts in one of 12, evenly spaced holes around the periphery. I built it from plans in Model Engineer's Workshop a number of years ago. Actually, I'll try to post some pictures and maybe a video of it later today in the tools section. I use it a lot since it's quick to set up and pretty handy for lots of rotary operations.

Chuck

 

[cfellows]

Had about 6 hours out in the shop today. The temperature outside hovered around freezing all day, which is cold for Austin, but my shiny new electric heater kept it comfortable.

I bored the smaller end of the crankcase so I could install the crank pieces from either end. I had to make a new bearing block for that end which also meant drilling more holes and threading them... not my favorite activity! But, all is well that ends well. Here you can see the crankcase with the crank and con rods installed. So, next, it'll be on to the pistons.

Chuck

 

[Powder keg]

Looks like your making good progress Chuck.

 

[putputman]

Looking good Chuck.
Could you take a few minutes to tell how you assembled the crankshaft in the block and how you keep the shafts in line. Is it keyed and pinned.
I have a heck of a time keeping the shafts aligned on a single throw crank.

 

[Deanofid]

I like the way it's going together, Chuck. Very Volkswagen-ish.

(That's a compliment!)

Dean

 

[ariz]

great work Chuck, very well done :bow:

what are those little pin (?) that I see upward roughly inline with the shaft?

 

[vlmarshall]

I like that crankcase idea, and the look of the assembled parts.

I like the way it's going together, Chuck. Very Volkswagen-ish.
(That's a compliment!)
Dean

Darn right it's a compliment! ;D :bow: Ok, the crankshaft halves are 180 out, but it's close.

 

[zeeprogrammer]

Looking neat. I have the same questions about the pins and keys.
Oh...and don't forget about the pics for the rotary table!
[EDIT: Just saw you have another thread for it. Thanks!]

 

[cfellows]

Looking good Chuck. Could you take a few minutes to tell how you assembled the crankshaft in the block and how you keep the shafts in line. Is it keyed and pinned. I have a heck of a time keeping the shafts aligned on a single throw crank.

I'll take it apart later today and include some pictures of how the crank is assembled. At the moment, I'm trying to figure out how to keep my outside faucets from freezing up again tonight!

I like the way it's going together, Chuck. Very Volkswagen-ish.
(That's a compliment!)
Dean

Thanks, Dean, hadn't thought of the VW engine, was basing it more on the Liney RV2, only bigger (and different) ???

great work Chuck, very well done :bow:

what are those little pin (?) that I see upward roughly inline with the shaft?

Those aren't pins, they are dimples, also called witness marks maded with a center punch, so I know how to put things back together the same way.

I like that crankcase idea, and the look of the assembled parts.
Darn right it's a compliment! ;D :bow: Ok, the crankshaft halves are 180 out, but it's close.

Thx Vernon. The crankshaft is a little different than the VW to keep it simpler.

Chuck

 

[cfellows]

Here is a how the crankshaft, rods, and crankcase go together:

These are the pieces unassembled about as far down as it will go. Note that the main crank shafts and crankpins are soldered into the two end crank webs:

The big ends of two of the connecting rods are inserted through the piston holes on one end:

One end of the crankshaft is inserted through the end of the crankcase and the crankpin is inserted through the big end of the two connecting rods:

The large, center crank web is inserted through the other end of the crankcase and the exposed end of the crankpin is inserted into a hole in the center web. A set screw tightens against the crankpin to hold it in place.

The process is then repeated with the other end of the crankshaft, rods, and crankcase.

There is another setscrew on the other side of the center crank web to lock in the other end of the crankshaft.

Aligning the center web with the two outer webs is a wooley booger and I haven't figured out an easy way to do it other than trial and error. Probably won't be an engine that I will be disassembling very often!

Chuck

 

[Deanofid]

Gotta keep those wooley boogers out of the shop, Chuck.

The VW engine thing was made out of my fondness for flat engines. All of them in general. VW's in particular. I just like them.

Thanks for the assembly pictures.

Dean

 

[ariz]

yes, thank you for the assembly pics, I'll never find out how to do it without something 'to see' ;D