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So now just working with the Sol Plate, I got it where I wanted it and continued to drill the tap holes.

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While I was at it I also prepared the bearing bolt holes.
And the Sol Plate mounting holes for if/when I find it a home.

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Of course I have to tap.

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Paused for a moment to see how things were lining up ---

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Then went back and finished the tapping for the bearing studs.

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Another couple of views.


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And finishing up for today ---
I found a Base Plate from my D10 build, maybe I'll clean it up and use it for the base -

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Thanks for reading -
All comments welcome.

Next time --- The Steam Chests


Regards,
Jim
 
So nice to see that those matching holes came out located symmetrically within the sole plate's corners. A perfect job of placing the ten most crucial holes in the engine.

John
 
STEAM CHESTS

Started working on the two chests. The casting was very close to finished size.
So lots of skim cuts. Add to that file work and finish up with my linisher for polish.

I did the Low Pressure Chest first, then the High Pressure, and then the covers.

No drilling yet.

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Finishing up the Steam chests -

I guess holes come next.
I plan to drill the covers first and then
use those to locate the holes in the chests
and then the block.

Then I guess it is time to drill for the
covers too.

Thanks for reading.
More to come.

Jim
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Time to Drill.

Guess I need to drill holes sometime.

First I drilled the holes in the Steam Chest Covers.

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Then I used the cover as a template/jig for the Steam Chests.

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Then I used the Steam Chests to locate on the Cylinder Block.

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I Then drilled and tapped a couple of holes in order to temporarily mount the Chest.

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Using 2 studs to hold the chest in place, I used the "clearance" drill to locate the placement and then drilled for tapping.
After the holes were drilled, I used and Number 2 Tap followed by a Bottom Tap to prep for the studs.

I only went in 1/4 of an inch. The drawings do not give a depth.

Then I added the studs and tested the fit.

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And finally the cover.

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Tomorrow the High Pressure Set.

Thanks for reading,

Jim Pope
Denver
 
High Pressure Steam Chest

Followed the same process.

First use the Chest as a template.

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Use the "Clearance Drill" as a marker. Then tap a couple of holes to hold the chest in place.

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Then continue to mark and drill the remaining holes.

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All done with the first part of the steam chests,

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Cylinder Tops and Bottoms next.

Thanks for reading,
Jim
 

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Hi Jim - Yes, Dorian did roar through here but nothing like down South - the ocean is cooler up here.
You have done a lot of work on your engine in a relatively short time! You must be quite pleased to see the results - John


 
Crosshead Bracket

This is a Bronze Casting - known as gunmetal in some places.

It came fairly rough, lots of flashing.

There are two drawings for the bracket. One for the version without the reversing gears,
and one showing the addition of the rod from the reversing gear kit.

There are conflicting measurements.
The thickness of the bracket is 1/4 inch on the first set of plans,
and is reduced to 3/8 inch on the set from the reversing gears.

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I chose to go with 1/4 inch.

After cleanup and reducing the thickness of the bracket,
I needed to drill for the rod.

So I mounted the bracket in a vise, and attached it to an angle bracket.
making sure all is level, square, and plumb.

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Then I located the starting point on the "top" rod

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Then the drilling -

I used an assortment of drills, starting small and then larger.
Then I used a long drill to get a pilot hole thru the bottom
bracket.

I used a small mirror to watch the progress from below.

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Then finished with a reamer.

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Then I used the rod as a mandrel in the 3-jaw and left the other end a little "loose" in the tailstock drill chuck.
Worked the ends to be symmetrical to the rod.

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Jim, my plans both show the same dimensions as yours: the 1980 drawing for the non-reversing bracket shows 1/4" thickness while my 1970 diagram for the reversing bracket is 3/16". I made mine 0.213" thick for some reason. Even at that it is a little too thick as I could hardly get the crosshead back washers to clear the bracket when bottoming out (and I used even smaller rectangular washers rather than the ugly(!) round ones suggested).
A little judicious milling on the top of the bracket just where the slides meet it would solve that problem without needing to make the entire bracket thinner.

I can't see why it should be different between the plain and reversing engines. However there is a different location specified for the bottom holes on the slide brackets between the Compound and Twin (which I thought were identical in that respect). On the Compound the holes are 1/8" from the bottom of the slide - on the Twin it's 3/32". That extra 1/32" clearance would make a difference to the sliding back washers...

Nice progress!
John
 
Bet your old shop steward has gone back to school - however this one looks pretty capable as well.
I spent a little time over the last few days putting up webpage about a small marine gas engine model that I built - but all the while still thinking about our compounds!
- John
 
Went back to work on the bracket and slides.

First - located drilled and tapped the holes in the bracket.

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Then started on the slides. First a little layout.

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Then I drilled the corners of the slot.

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Followed by the use of a rounded 3/16 mill.

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Then the countersink.

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And finally in place.

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The slots still need a little cleanup with a file.

So what next?
Pistons ?
Crankshaft?

We will just have to see.

Thanks for reading.

Jim
 
Beautiful countersinking Jim. Getting that right is often more difficult than meets the eye and surely it is a sign of good workmanship.
After the pistons, glands and crossheads are done you will be able to determine how accurately everything lines up and slides. That's the important part. The cranks and connecting rods then should be just a simple fitting job.
I think that hound dog is keeping you working well! - John
 
Greetings again.

Just wanted to say that I have had to pay attention to my "Day Job" and have not gotten back to this project for a while.
I will probably pick it back up after the new year.

Everyone have a Happy and Safe Holiday Season.

Regards,
Jim Pope
Denver, CO USA
 
Well, that was an interesting year!
I got sidetracked with the other 1/2 of my hobby - which is the construction of the
crafts to put these engines in.

So I spent the last 14 months in the Model Boat side of the shop. and neglected this
build until now.

I am cleaning the dust off, and studying the drawings.

Here are a couple of my "side projects"

Thanks for reading, I hope this thread stays entertaining.

Regards,
Jim
JPDenver
Denver, CO USA

Look for me on YouTube - Hilltop Boatworks

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