Newbie and the Cylinder

[Foozer]

Trying another motor sub assembly, never made one of these so only one way to find out. Can I do it with only the Boat Anchor lathe I have

Idea on paper, be a steam chest of sorts also after I tackle this part

Looks easy enough 0.375 bore for a 0.750 stroke
Have had trouble working from the outside in, bore hole ends up off center, so this time drilled/reamed the hole first, turned down a piece of stock with a slight taper to it and wedged the soon to be cylinder upon it. Turned the outer profile and, well it works.

For the tail section of the assembly needed a slot cut so used one of those cross slide little home made V-Block thingies to hold part and used a Dremel router bit in the lathe chuck, cranked the lathe up about 4000 rpm and achieved the slot cutting. (clamp removed for photo)

Use the soft jaws, really like that tool, gave it a little bore on the jaws to hold the tail section and reamed the innards to clean up and size the innards.

The slot is 0.250 so the inner bearing surface for the piston rod will be 0.312. Should be able to see the workings while maintaining enough meat for the sliding bearing.

Have to cut the cylinder head, some bearings and connecting rod clevis fitting. Biggest challenge which could trash the whole thing is drilling the holes to that will be for the stud & nuts aimed to hold it all together.

Its all just practice, finding out what I can and cant do with what I have

Robert

 

[hitandmissman]

Looks like that turned out real nice. Plus gave me another idea to try out. Thanks.

 

[Foozer]

Looks like that turned out real nice. Plus gave me another idea to try out. Thanks.

Hope its successful for you

 

[Foozer]

Few cups of coffee, feed the chickens and back to turning some parts.

So I've got the basic cylinder and tailpiece done

Time for the Cylinder head. Just a little piece of brass where the soft jaw chuck really helps out. Using the same bore jaws to fit part as the other two pieces it allows the soon to be cylinder head worked up close. Got it turned down and profiled.

Using the rocker post sans the rocker holds the bit securely giving better results over the QCTP for in close work. Turned out a partial piston/rod and now its time for the tiny sleeve bearings and rod clevis portion.

Off course I dropped and dinged the tailshaft, piston rod looks bent in photo, must be the light. Made two of the piston/rod pieces. That AL gets a little springy at the smaller dia 0.187. too big (0.010) a cut and, another one for the "Shelf of Shame"

Next up, bearings and clevis. Saving the drilling of hole for last. Scrap or not scrap, that is the question this newbie has yet to encounter

 

[arnoldb]

That's looking good Robert Thm:

Looks like you discovered a new optical illusion, unless that's been brought on by the "hot sauce"

Regards, Arnold

 

[Foozer]

The smaller the part the longer it takes, I'm gonna need more "Hot sauce"

Task was to make the piston rod bearing for the tailstock. Got a piece of bearing bronze and thoroughly trashed the first attempt. 'Nuff to say that attempt now resides somewhere in the neighbors yard. The piece is supposed to be 0.375" long by 0.313" dia with a 0.187" hole in it. Also to have a flange 0.016" thick by 0.425" dia. Lesson, Dont finish the flange first and expect to have enough material for the chuck to hold while facing the other end.

So after the second attempt, a little bushing in the freezer and tailstock heated to 350 degrees it just popped in slicker than Goose Doo.
The mating side of the cylinder was also relieved an amount equal to the bushing so that when assembled the bushing will be captured. Sure its more than needed but as long as I am figuring out how to cut stuff, what the heck.

So not a big deal here Just a little piece of the puzzle. Got to do some math to figure exactly how long the connecting rod is to be, another day another task

Robert

 

[zeeprogrammer]

'Nuff to say that attempt now resides somewhere in the neighbors yard.

Is that where you keep your 'Wall of Learnings'? Or do you have more than 1?

How does the cylinder attach to the tailstock? Or does it? That is, does something press the two together?

Thanks.

 

[Foozer]

Is that where you keep your 'Wall of Learnings'? Or do you have more than 1?

How does the cylinder attach to the tailstock? Or does it? That is, does something press the two together?

Thanks.

Neighbor, well its a ten acre piece that the county just bought. Dont know what they be building, but anything I can do to help them out Got some larger pieces I'd like to throw at em to acknowledge all the dust they been raising lately

"Wall of Learning?" Got to go up the "Stairs of Stumbles" to view that one.

Idea was to use thru studs outside the cylinder with nuts. May have taken a big bite of the apple, drilling those holes, that's where a mill table would sure make it easier. Just have to see what develops in the "Darkroom of ideas"

 

[zeeprogrammer]

Got to go up the "Stairs of Stumbles"

Rof}

see what develops in the "Darkroom of ideas"

Rof} Rof}

Thanks. I'll have to remember these next time I'm in the 'Basement of Despair'.

 

[Foozer]

From the Barn of Boo Boo's another one goes upon the Shelf of Shame

Someone forgot to check the tailstock alignment, same someone only measured the connecting rod diameter at one point. Tapered connecting rod just aint gonna work to sliding thru the bushing.

After getting the tailstock lined on center, real PIA when tightening the hold down moves it farther than the correction amount, at least got the shaft to 0.188 overall give or take 0.0005. Best this ol AA109 is gonna do. Also decided to fancy it up and made a piston out of bearing bronze. Threaded the end 10/24, dab of Loctite and put a tapped round of bronze on it.Turned the whole assembly at one time, once in the lathe, I'm not moving it till its done.

I see why the hard solder route is favored, turning small dia is, well that torch is looking a lot more practical every day.

Still have a bit of sizing to do on the piston, taking a break for the brides sake before hitting the sandpaper to final stage.

 

[Foozer]

Piston finished, turned all the piston material extra down to a final length of 0.200. Probably a tad on the long side for a double action cylinder but wanted to ensure a thread or two was still left on the shaft to hold the piston to the rod. Leaves me 0.050 clearance at each end of travel.

And the obligatory "Pop" test
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Couple more pieces to do, like a steam chest of some sort, and this cylinder assembly is done.

I should quit fooling around and actually make something

 

[zeeprogrammer]

I should quit fooling around and actually make something

Oo. Oo. An opportunity. Nah. I'll be nice.

Very nice Robert. Thanks for posting the 'pop' video. Helps to see/hear it rather than be told what it should do. (Mine didn't even wheeze.)

Do I have this right?...Connecting rod is threaded on one end and a bronze piston is threaded onto it? If so...can the piston unthread itself?

 

[Foozer]

Oo. Oo. An opportunity. Nah. I'll be nice.

Shy are we?

Very nice Robert. Thanks for posting the 'pop' video. Helps to see/hear it rather than be told what it should do. (Mine didn't even wheeze.)

Had you in mind so as long as I had a good popper in hand, might as well hear what the "Pop" sound is.

Do I have this right?...Connecting rod is threaded on one end and a bronze piston is threaded onto it? If so...can the piston unthread itself?

Your right it is threaded. Took a center punch and made a couple prick marks on the rods thread to give em a slight deformation (buggered em up a bit) A drop of Loctite and it should be more than able to withstand any tenancy to un-thread it self. Dozen different ways to achieve the end, most require smaller pieces that start to get all to fuzzy and fiddly for me to deal with

 

[Foozer]

So thanks to ZEE and the thread on indicators, thought I'd give it a try on setting up to drill a hole. Normally for this I'd just skim the face of the soft jaw and bring the cross slide attachment up to it flush to square it off. Took the longer route, set a piece of 1 inch tool stock 6 inch long in the jig and used the indicator to set the jig square. Locked the slide down, removed any extraneous bit and called it good. Actually overkill here, the play in this lathe makes for no real difference in final result.

Mounted the piece to be drilled, the sliding bushing for the piston rod that sets into the tail shaft and drilled two holes. One undersized for the 0.125 connecting rod pin and another about 0.063 which will help secure the bearing to the shaft once the final position is established.

Even used a bit of soda can as chaffing material . . .

So far this exercise looks like this. Actually moves free enough throughout its travel. Small bit of binding but a final work with some 600 paper ought to clear that up.

Still stalling on drilling the head bolt holes

 

[zeeprogrammer]

Looking good.
How does air/steam get in/out?

 

[Foozer]

Looking good.
How does air/steam get in/out?

Haven't a clue, yet. Just know it will require some itty bitty holes being drilled. A steam chest to hold the valving of some sort made. You know, balance big ideas against lack of ability.

Next phase is to drill the head bolt holes, hoping I left enough room for 2-56, dont want to go smaller.

Robert

 

[Foozer]

Finally drilled them itty bitty holes that will accept studs with 2-56 nuts at each end. Loose fit 0.096 and I sure hope that's right. Just made it on the tailstock end. I sorta over cut the recess so the bolt holes break out into it a bit. But they are evenly spaced so i could say "Designed it that way! Yup"

Well now to find some stock to make the studs out of, and a 100 mile (160km) trip to get a 2-56 die, or two, or three.

 

[bentprop]

Nice work so far,Foozer.
Just a thought,you can get 2-56 threaded stud in any shop that sells RC airplane stuff.It's used for attaching clevises to pushrods.Might save you a long trip?
Regards.Hans.

 

[Seanol]

Foozer,
I hear you on the tailstock alignment.

Looking good though. What type of engine is it?

Sean

 

[Foozer]

Nice work so far,Foozer.
Just a thought,you can get 2-56 threaded stud in any shop that sells RC airplane stuff.It's used for attaching clevises to pushrods.Might save you a long trip?
Regards.Hans.

Thanks for that tip, I'll find a shop around somewhere. I'm out in the boondocks north of Seattle. The drive's not so bad if I time it to miss the rush hour jams.

Foozer,
I hear you on the tailstock alignment.

Looking good though. What type of engine is it?

Sean

Thanks,
Haven't a clue actually. I've never done this sort of stuff, kinda learning as I go along. Just sort of an exercise to find out what I can and cant do with no talent and the tools I have. A drill press and an old small lathe.

I'd get laugh'd out of Dodge if I posted how I drilled the itty bitty holes

Keeps me hopping