Mery 6-stroke kit.

[Jack3M]

Hey all,
Saw one of these at the Great American Steam Up in Brooks Oregon last summer and fell in love with it. Apparently it is one of the more rare, but highly spoken of. Purple (powder coat???) Apparently the builder got lucky and some high falutin' pinstriper did the pinstriping on it. It really is a gorgeous machine. The only original that still runs was also there and got to see that in operation too. I hope to even replicate the cooling system.

This is for now, a sideline, fill in project until the one ahead of it is completed. This way when one project is held up it will be possible to work on another and chill the brain cells as needed. Also we have another member starting on one also and we have been in contact. I welcome interaction, but please lets stay on the given topic and questions. There is another build out there by a member here,
http://www.teqknow.com/Shop/Mery.html
That one is done by someone who knows their pooh, I am a wannabe machinist so it might be of interest to watch me stumble along.

First order of business is to get the 60 sheets of drawings (8.5x11) into a notebook in the protective plastic sleeves. Learned about using sleeves on another project and in the oily dirty environment they are just awesome. Additionally there are a few sheets where it will be necessary to refer back and forth. With greasy fingers this quickly soils good drawings. Plus this way they can be kept in order in a 3-ring binder. Frankly for this type of project I prefer the smaller sheets over huge plan sets. (Actually turning one set into 8.5x11 sheets for a traction engine in my spare moments.)

If anyone is interested, my casting is #361

 

[Jack3M]

Though not the Mery, a task necessary to learn before working on the Mery. That task/skill is cutting your own gears. On a different project, a steam donkey, the gears necessary (according to plans) would have cost almost $250....plus shipping. NOT. So, cast up some gear blanks, two were 4.5 inches, one one one inch diameter, 22 and 90 teeth. Through several errors, and making my own gear hob, I learned the skill. How cool

 

[Philipintexas]

I built this engine about 15 years ago with castings from Martin. Can’t say enough good about his castings. Not the easiest to complete but it runs well on propane. I added my own water pump running off a second eccentric and it makes a good water-heater. I was surprised at the amount of heat it produces. I didn’t make a cooling system, just a large reservoir as it heats the water quickly. The most amazing thing is the size of the exhaust hole(s), about the size of a small pencil-lead and it would not run on a larger hole..?? Very odd since the engine does an exhaust and then a second intake/exhaust through those tiny holes.
Another idiosyncrasy is the difficulty in sealing the two intake-valve “Boxes”. Combustion takes place in them before igniting the cylinder so the pressure tends to blow gaskets at the plug cover. Leave as much sealing surface as possible...

 

[Jack3M]

Thank you for the advice. Did you try metal gaskets on the combustion chamber?

 

[Philipintexas]

I finally found some gasket material that stood up to the pressure. It’s just the small sealing area that presents a problem.

 

[Jack3M]

Well, am beginning. I may have to farm out the work on the main portion due to my machinery not being big enough. Looking at ways to do this on the lathe, but even that is doubtful at this point. It is possible to true the base, just none of the boring it looks like to me.

 

[Jack3M]

After a long discussion with a retired machinist friend of mine, it sounds like if I take it really slow and easy with modifications to tooling this can be done. Building a holding jig now for the lathe slide. Guess I should get a photo or two.

So far have made the base parallel to the C/L. This was done by smoothing down the parting line on the top of the body. Indicated this out using shims. Then trued up the 3 locators provided by Martin Models in the casting. In turn then it could be flipped over and the bases trued to the horizontal to the model centerline thru the crank and piston....

Measuring for the height to the center of the crankshaft by the drawing numbers puts the C/L off low by 1 /4 inch or so. Taking that much off the bases would destroy them so that value in the drawings will have to be changed to get true center.

The jig was marked to the center of the lathe using a piece of stock turned to a point and compared to the tailstock center for verification. The base was drilled at it's mount locations and them bolted to the jig which was squared prior. ( 2.5" thick aluminum)

Still need to finish the hold down points in the jig, then modify the slide to accept a couple M8 bolts for balanced tie downs for those points in the jig (4). This concept will use two existing M8 holes so will make these parallel with the existing. Hopefully I can use the tie downs I have and don't have to make those too. I will try to get some photos tomorrow.

 

[Jack3M]

Sure am tired this evening. All that thinkin' I guess. Had to do other things this morning, like get a hunk of granite to get a flat surface. That helped me figure out the height of the C/L.

Then spent a great deal of time on the jig. Of course the new bolts (Hillman Fasteners) stripped out...in aluminum right away and had to get replacements. Milled out the slots in the big chunk and using 3 tie down setups got that working, indicated out, and put the main base on the jig. Double checked height related to C/L and that was still okay.

Took it all down and made the boring bar, which I needed the lathe for. I am not sure this will be solid enough, using 3/4 tool steel and boring head. The bar itself got a carbide insert, easier to change an insert than sharpen tools Considering just waiting and using a bigger diameter bar, like 1.125 dia.

Indicated out the boring bar head as mine is R-8. It fit great in the 4-jaw without issue.

As promised, pictures, most are the tiedown setup, some showing the methods to true things up.

 

[Jack3M]

So I spent hours yesterday skimming. Had to take enough cut to prevent chatter. Was interesting how speed of travel and depth of cut were very independent of each other. After about 40 passes the smoothest finish was acheived. I stopped about 0.075 from finished diameter waiting on an internal measuring tool to arrive. So at this point I don' know if I have a taper or not. Thinkin on how this is working, I should have the same amount of flex all along the cut, not just at one end. We shall see.

I am going to have to pull off for a few days to work on a house remodel issue that needs preparation for contractors
.

 

[Jack3M]

I think I would like to include a statement of lack of knowledge. I am just going at it here. No special training, not a machinist, it's all play to me and I surely am doing some things incorrectly. What I show is just my approach and does not mean it is the correct way to do things. It is just a lifetime of scale modeling from plastic kits as a kid to scratch building static steam engine replicas to draw from. (It is rare I do a kit now, but this kit was just too kool to pass up and is just like scratch building except I don't have to draw up the plugs and cast the parts and they do much better castings than I do.)

 

[Jack3M]

Having issue with tolerance. There is no way I have tools accurate enough to measure inside diameter to within .0005".

First, I see no need for that tolerance in the cross slide area, and the front part I can measure more accurately which is what I believe is the important part as the cylinder mates there. I can probably get .001 there. We are talking 1.5 inches diameter.

My inside measuring is giving me variations of .001-.002". Taking several measurements and then averaging, throwing out high and lows. Anybody got 2 cents worth of opinion on this?

 

[Jack3M]

Well, I just settled for 1.5. The end shown in the photos is now faced and the recess for the cylinder assembly created. Took my face mill and used the 4 jaw. Piece of cake. Plus tore up the kitchen some, with more today. My body can only take so much of that really physical stuff at a time. So between all, this project gets some attention.

As far as the crosshead section, that will get honed after the oiler is tapped and drilled, within a thou there.

 

[Joe]

Having issue with tolerance. There is no way I have tools accurate enough to measure inside diameter to within .0005".

First, I see no need for that tolerance in the cross slide area, and the front part I can measure more accurately which is what I believe is the important part as the cylinder mates there. I can probably get .001 there. We are talking 1.5 inches diameter.

My inside measuring is giving me variations of .001-.002". Taking several measurements and then averaging, throwing out high and lows. Anybody got 2 cents worth of opinion on this?

Only worth what you pay for it but could you turn a gauge pin to the 1/2 thou tolerance and use that ?

JG

 

[Jack3M]

Only worth what you pay for it but could you turn a gauge pin to the 1/2 thou tolerance and use that ?

JG

That is close to what I did, not a gauge pin but steel that was dead on OD. When it was difficult to pass but passed I called that good enough. Again, I don't think the clearance is that important until you get to the mounting end....that is critical, but that is not difficult to get good measurement and slip the gauge in.

 

[Jack3M]

Caught up on kitchen waiting on contractors to do their thing for awhile so get some time to play. Got the hole for the gear axle done. Drilled from one side only, fearing walking, but not so. Used a cobalt bit, went slow and drilled like I was working in brass, just pecking. Came thru straight so something is lined up right I guess.

 

[Jack3M]

Then with great trepidation the area at 45 degrees where the bearing cap goes was cleaned up to get the whole 45 degree. By using the previously measured and punched location dots for CL of the crankshaft was used to score a line across both, these too also got a punch mark so the calipers would have a definite spot to measure from and marked the end edges which stick up and prevent end-to-end movement of the caps. I could be +/- a degree here, but don't think it will be much issue if the rest fits and later drilling is true. Taking a break now, but working on the bearing cap right now, maybe more photos later....

 

[Jack3M]

Where am I? Bearing caps. Straightforward mill working.

Then had to stop to make a plug to mold some bronze for the bearings. Soft solder and bronze don't like each other, even with flux. But they are soldered and ready to hit the lathe. Will do the outside to dimension, and several thousanths undersize for the hole for later line bore.

 

[Jack3M]

Well bronze doesn't work well, will not solder together with plumbing solder and don't want to use silver solder, so working on brass now, at least it soldered.

 

[Jack3M]

Brass worked like a charm. Still soldered together. After boring the base, drilling a combination oiler and locator pin hole, it should be good to go.

 

[Jack3M]

Not much to say, Got it all reamed and the shaft turns glassy smooth with fingertips. Halves separated and solder wiped off while still hot, recheck shaft after all said and done. The first photo is how I kept the bearings tight while drilling.