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mklotz
04-13-2007, 01:03 PM
This is an interesting little pump to a design by Elmer Verburg. On the right is a double-acting steam engine with D-valve visible through the plastic cover on the steam chest. It directly drives the piston of the double-acting steam pump on the left. The exterior isn't much to look at it but inside are four working ball check valves.

Directly connecting the engine to the pump poses a problem for attaching a flywheel. Elmer solved this dilemma by driving the flywheel with a ball joint on the end of the arm attached to the connecting rod. A side effect of this technique is the fact that the pistons rotate slightly as they move back and forth.

In operation, pumping mineral oil, the pump produces a nice steady stream due to the fact that it pumps on both sides of the stroke.

http://i81.photobucket.com/albums/j234/mklotz/pump.jpg

rake60
04-13-2007, 02:07 PM
Very Nice Marv!
I just started the Pumping Engine with the catwalk. A broken 1/16 drill bit in one of the 11 degree holes in a cylinder convinced me that it was time to take a break from it... Still trying to figure out if I can salvage it.

Rick

laddy
04-13-2007, 02:25 PM
Beautiful job!!! I have his book, I have to look that one up. Superb!!!

mklotz
04-13-2007, 04:19 PM
Very Nice Marv!
I just started the Pumping Engine with the catwalk. A broken 1/16 drill bit in one of the 11 degree holes in a cylinder convinced me that it was time to take a break from it... Still trying to figure out if I can salvage it.

Rick

That one is on my to-do list. Small diameter angled holes are a trial. Make sure the work is well-supported from below at angle - I use a no-longer-good-for-metrology sine bar in the milling machine vise. Use a small diameter center cutting endmill to make a flat on which to start the drill. Peck like a mad chicken.

rake60
04-13-2007, 04:28 PM
I had drilled both holes in the first cylinder, and broke the bit in the first hole of the second one. I had the piece set flat and square in the mill vice with the head set at 11 degrees. It snapped off when it broke through to the milled port in the top of the cylinder.
The plan was to make the cylinders aluminum and the covers and steam chests brass, but I do have a 1" square bar of brass in the stock box. Maybe it would be a little less gummy for drilling and porting those small holes.

Your opinion?

BTW GREAT information on your web pages!

Rick

scott96088
04-13-2007, 04:38 PM
.
The plan was to make the cylinders aluminum and the covers and steam chests brass, but I do have a 1" square bar of brass in the stock box. Maybe it would be a little less gummy for drilling and porting those small holes.

Rick

Brass will grab a small drill and break it off too!
copper is even worse to drill.

You need blunt the cutting edge just a bit.

Scott

rake60
04-13-2007, 04:47 PM
Thanks, I'll try that.

Rick

mklotz
04-13-2007, 04:50 PM
Lots of kerosene when drilling aluminum. Track the depth of the drill in the work (I use a DI depth gage) and peck even more gently as you reach the break through point. Also, consider using a harder grade of aluminum. IMO the brass would be better but be sure to use a drill that's been modified for brass, i.e., no rake.

Alum has been recommended for removing broken taps/drills from aluminum. Search the archives.

Orrin
04-16-2007, 02:45 PM
Beautiful job, Marv! Are the plans for that in Elmer's Engines? I don't recall seeing it, before.

Regards,

Orrin

Your Old Dog
04-16-2007, 03:06 PM
Marv Unchained!

You been grinding out the work lately Marv. Really nice to see someone being productive! It must feel pretty good.

mklotz
04-16-2007, 05:07 PM
No, YOD, I can't lay claim to a sudden inspired spurt of productivity. (To the contrary, between the dentist and my latest grandson, I've been conspicuously absent from the shop.)

The reality is that I treated myself to a new camera (and, coincidentally, a new computer and DSL connection to support it) and I've been documenting a lot of previous work to put up on our club webpage. Since I had all the words and pictures prepared, it seemed logical to post them here in the fond hope that some of it might be useful, or at least inspirational, to the members.

Orrin: Look on page 155 of "Elmer's Engines".