Chris's Marion Valve Winding Engine

[Ye-Ole Steam Dude]

hello Chris,

Beautiful work 

Have a great day,
Thomas

[mike mott]

Nice work Chris! I am amazed by what you are accomplishing with the small lathe and mill It is difficult to tell what size endmill you are using for the block clean up and shaping it looks like about 1/2 inch.

Mike

[crueby]

Thanks guys. Mike, that is a 3/8" end mill, the holder I have takes 3/8" shanks so thats the largest size I buy. For scale, the web sides are 3/8" thick, 3/4" wide, distance between centers on the shafts is 1".

[Johnmcc69]

 
Looking good Chris!
 
  John

[mike mott]

Thanks for the answer Chris.

Mike

[scc]

Brilliant build thread Chris,   I am learning so much            Terry

[crueby]

 

[crueby]

Continuing on with the crankshaft, I want to have the flywheel in the center between the cylinders, but still be able to remove it if need be. Making a two-piece flywheel was not in the cards for this build (will do one someday), so opted to split the crankshaft rod in the center. Sort of like George did his, but I wanted to ensure that the two halves did not pull apart horizontally - added a hook to the overlapped section in the center. This section will be inside the taper-lock on the flywheel, so will be held together. After measuring out the lengths of the rod needed, allowing for putting a winding drum on one end, I notched the ends of the rods:

Here they are test fit together:

All looks good, they fit snug and without a step between the outsides, so that is a go. Here is what the whole assembly will look like - I put the connection inside the taperlock and tightened it down, no wobble. 


Marked out the locations of the webs on each shaft half, and got out the loctite to hold them in position. Once they have set up well, the webs/shafts will be drilled/reamed for 4/0 taper pins for a secure connection, then the remaining bit of the rod between the webs can be sawn out. The center connection laps made it easy to line up the webs 90 degrees apart - one lap horizontal, one vertical, when assembled it will be all properly offset.

[crueby]

Got the holes drilled for the taper pins - first one was a bit of a botch, the website I looked up the drill size on had PART of the page from the handbook copied in, so it misled me on which drill to use, and I went one size too large, fortunately there was enough room to plug it and re-drill next to it.

Then used a matching taper reamer on the holes (4/0 pins and reamer)

pins driven home:

and sawn/filed off flush. Also cut through the main rod between the webs to finish off the shape. Here it is all assembled on the flywheel:

Very happy with how that came out, now can start on the bearing blocks/stands for the crankshaft (just remembered that I still need to make the shoulder bolts for the crosshead/con-rod connection too).
 

[derekwarner]

Chris.....

Prior to the final assembly, do you degrease the pins, put them on a small sheet of Gladbake cooking paper then in the freezer for 24 hours.......degrease the cranks & use Loctite primer then a squirt of high strength Loctite then very smartly insert & gently tap  the pins home?

[A few years back, a young professional Engineering student  in his 5th year at University decided to go one better than the advice offered and used liquid Nitrogen [poured into a Polystyrene drinking cup] knowing that it would provide a greater dimensional shrink

The result was the pins at the lower temperature when contacted, boiled the Loctite and left a degraded deposit that did not cure]

About the only correct element in his plan was to use the double Polystrene drinking cups  for the N2 ...he didn't need to use Gladbake paper...however the Tefon impregnation in the paper stops the pins sticking to the paper in the freezer

Derek

[Ye-Ole Steam Dude]

Hello Chris,

Boy that looks really nice, kind of strange seeing the Flywheel in the center of the Crankshaft. 

Have a great day,
Thomas

[crueby]

Chris.....

Prior to the final assembly, do you degrease the pins, put them on a small sheet of Gladbake cooking paper then in the freezer for 24 hours.......degrease the cranks & use Loctite primer then a squirt of high strength Loctite then very smartly insert & gently tap  the pins home?

[A few years back, a young professional Engineering student  in his 5th year at University decided to go one better than the advice offered and used liquid Nitrogen [poured into a Polystyrene drinking cup] knowing that it would provide a greater dimensional shrink

The result was the pins at the lower temperature when contacted, boiled the Loctite and left a degraded deposit that did not cure]

About the only correct element in his plan was to use the double Polystrene drinking cups  for the N2 ...he didn't need to use Gladbake paper...however the Tefon impregnation in the paper stops the pins sticking to the paper in the freezer

Derek

Nope, never done any of that. For degreasing, usually either alcohol or for bigger parts have a can of Brownells degreaser made for gun parts, works great. Even running very hot water through works well, evaporates off. A lot depends on the version of loctite too, some are more tolerant of leftover oil.
These taper pins are a really tight fit, the loctite may do nothing for them, I had it out so put in a drop anyway.

[crueby]

Hello Chris,

Boy that looks really nice, kind of strange seeing the Flywheel in the center of the Crankshaft. 

Have a great day,
Thomas

Yeah, not usual on a model, have seen some real ones like that, with the two piece bolt together type flywheels. I just thought it looked good there. The outer end of the shaft will get a winding drum, like for a mine hoist. Remember, this is not a scale model of any particular engine, just a made up one similar to the type, so I can do what I like style wise. Nice to go a bit freeform for once!

[steam guy willy]

Coming along nicely...looking great 

willy

[crueby]

With the crankshaft done, now it needs a set of pillars to hold it and its bearing blocks. As some of you remarked early on, the original posts looked too skinny, now even the heavier versions I had changed the drawings to are still too light. So, I went through the rack of steel bar stock and picked out a set that added up to the correct height:

These look more like it for an engine that would be hauling mine elevators or rail cars up an incline. They will get squared up and held together in the stack with screws from underneath. The top pair of square bars will be the bearing blocks which will be drilled/shaped to take bronze bearings and screw down from the top.