Elmer's #33 - Yet Another Mill Engine

[vascon2196]

Great job Stan...lots of great pics! Your Kurt vise looks brand new...I'll trade you for an antique Kurt vise equipped with accidental drilled holes to give it that "swiss cheese" look.

Make sure you finish this engine for Cabin Fever...I booked my hotel this past weekend!

 

[Sshire]

I think I'll pass on the vise trade. It is brand new. A holiday gift.
It'll be good to see you at CF. if you can, bring the Henry Ford engine.

 

[Sshire]

Elmer’s #33 - Mill Engine
Episode 10
Screwed!

I hadn’t expected to be in the shop today, but I finished a short consulting job early (consulting means that you know slightly more than the people contracting you.)

Figured I’d get to something and the shoulder screw that connects the con rod to the crank was a likely suspect.

A short piece of 12L14 .25” hex bar in a collet. Turned the shoulder to .1875 to fit through the con rod.



Next, the part to be threaded turned to .125”



Threaded to 5-40.



Parted off. I left plenty of hex because I thought that Elmer’s head height looked a bit thin. I was comparing the dimensions in both Elmer’s drawings and the specs in Machinist’s Handbook.



Machinist’s Handbook head height was slightly higher than Elmer’s, but I thought that, visually, they were both too thin. I went about 20 thou thicker.

A 30 degree (as speced in than Handbook) carbide tool to chamfer the corners.



Completed shoulder screw.



Here’s where it’s used.



Richie, my UPS guy, delivered some ¼” brass hex from Online Metals for the pack nuts. Those and a few other parts are for tomorrow.

 

[dreeves]

Looking good Stan. Can't wait to see her running.

Dave

 

[Sshire]

Other than machining the flywheel casting that arrived from PMR, all parts are done.
Look for the finished stuff tomorrow. I do have a "test" flywheel that mysteriously bent itself off center, but it's close enough for testing.
Just to hold you over, here's something to watch.

[ame]http://www.youtube.com/watch?v=-VUK8bgnDeM&list=UUtv2FL7ehRo9CV-vt2kPlWw&feature=c4-overview[/ame]

 

[Sshire]

Elmer’s #33 - Mill Engine
Episode 11
Elmer! Come in for dinner!

Elmer Verburg sits at his drafting table putting the finishing touches on a steam chest drawing.
“Let’s see. Intake ports. Threaded mounting holes. Nine tiny holes. Ha! That should give the guys with .050 backlash a fun day.
Hmm, did I miss anything? Oh, yes. The hole for the exhaust port. I have it on the cutaway but not on the top face drawing. Also need a drill size for the hole.”
Elmer picks up his pencil to add the missing elements to the drawing.
Suddenly, “Elmer! Come in for dinner. You can finish that later.”



Of course, Elmer never does add the two missing elements and I spent some time this morning figuring that one out. When I made the cylinder, I remember noting that the exhaust had to exit somewhere, but in the frenzy of making the other parts, like Elmer, I forgot. So the cylinder goes back on the mill for drilling the exhaust channels.



Now to bevel the base and sub-base. The angle isn’t critical; it’s supposed to suggest that the bases were cast and have a draft angle. 5 degrees looked about right so the angle vise was clamped in the Kurt (anything not to have to re-indicate the Kurt).



The 2” face mill bevels the long sides



A side view.



Now that those edges are finished, the ends will be done. I used a high helix end mill. Nice finish on the non-ferrous stuff.





Milling is finished.



The machining marks removal department.



Since the base and sub-base are going to be painted, I started by bead blasting the parts.



This was followed by self-etching primer and black gloss enamel.

While the paint is drying, I moved on to the two pack nuts: one for the steam chest valve rod and the other for the piston rod. Started with .250” brass hex in a 5C collet. Marked the part to be threaded to length.



Then turned to something under .190 (.186 IIRC) for the 10-32 thread.





Through drilled for the rods then, parted off.



The piston was just the littlest bit tight. Timesaver fixed that.





I’ve decided to do the floor in lumber planking. First I scribed around the bearing tower and the sub-base. This will tell me where NOT to lay my flooring.



Basswood stripping with Bartley’s Gel Stain. Cutting and fitting followed.



Double-stick carpet tape to affix the stripping.



You’ll see that when it’s finished. If you don’t know by now, Richie is my UPS guy. Since he brought the flywheel casting from PMR, that needed to be addressed.

The soft jaws went onto the 3-jaw chuck. They were tensioned at about the right diameter and bored to grip the bronze flywheel casting.



More than half of the rim can be reached for truing.



Then, faced and the hub faced and turned. The part is then reversed in the soft jaws. Repeat.



Then drilled a bit under-size and reamed to .250”



Oliver removed the flash and cleaned up the corners.





Then to the bench. I started with 80 grit then 100, 120 and 220. I use the fabric-backed abrasive rolls and use a piece until it stops cutting or looks like old denim.



This is where I stopped for the day. Still need to smooth between spoke at the rim, then masking, priming and painting. That’s for tomorrow.