Chris's Holly Pumping Engine Build

[crueby]

Hi Chris, looks good so far. Are you counting cranks, or just working to the lines?

Counting cranks - the lines are there as a double-check for miscounts and for confidence that I am not way off.

[Don1966]

Looking great Dog, but I have to ask if you have a brass stockpile in your house that stuff is at a premium right now. Always outstanding work Chris….. 


 
Don

[crueby]

Looking great Dog, but I have to ask if you have a brass stockpile in your house that stuff is at a premium right now. Always outstanding work Chris….. 


 
Don

Yeah, prices are up, I've bought enough for the next several parts so far, and I buy 'drops' from Yarde Metals of roundbar that are about 1/3 the normal price, oddball sizes, usually about 3' long, that I use for the larger parts. This flatbar had to be bought at normal prices, though the price varied a LOT from different suppliers, this time Speedy Metals had the best price by far, maybe they had it from a prior pricepoint. I try to keep a stock of common sizes to avoid buying short lengths for a specific use, longer lengths tend to work out cheaper per pound, and get used eventually. Also, the income from my articles in Live Steam pays more than enough to cover all my projects, so I dont care so much about price!

 

[crueby]

Got started on shaping the ends of the engine bed plates - they are flat at the corners next to the frame mounting pads, then arc out in the center to give a little extra room for the cranks. The ends will be angled in, but I started with the mill head vertical to set the length. The parts are screwed one at a time to a faceplate mounted on the rotary table.

When all the ends had the shape milled in, I then tilted the mill headstock a whopping 2 degrees - just visible against the mill column on the left of the headstock.

To know when I had advanced in to the initial shape, I drew on the face first with a marker:

Then took several light passes, here it is halfway with part of the marking gone:

Another couple passes and all the marker was gone, same process on the other flat end and the arched center.

The sides of the beds stay vertical, its just the ends that they angled in. So, on to finishing the rest of the ends....

[Kim]

Is just the flat part of the end angled? Or is the curved part angled at 2^o also?  Hard to tell in the picture...

Kim

[crueby]

Is just the flat part of the end angled? Or is the curved part angled at 2^o also?  Hard to tell in the picture...

Kim

Hi Kim,  the curved part is angled as well. Just 2 degrees, but it does change the look, I was surprised that it's noticeable, at least in person. In the picture its upside down.

[cnr6400]

 

[crueby]

Hi CNR! 


Got the rest of the ends angled in on the bed plates, now turned them over to put the arcs in the recesses on the top surface...

Next? Well, I need to cut the arc in the opening in the center,  tap the mounting holes on the corner pads,cut the center opening out, and get things prepped for the bearing blocks and the bottom arched blocks...

[sid pileski]

Chris- My wife and I visited the Boston pumping station this weekend. They are pretty amazing engines to see in person. We were able to do the "below and above" deck tour.
So, we got to clime up on the Leavitt engine, and go below to actually explore the  bottom side of the Allis engine.
Our Docent was very knowledgeable. (I forget his name) He was in pumps all his working career. 
Only one thing that I kind of disagreed with him about.
In the pictures below, you can see a little gear that engages one of the flywheels for barring the engine. It is on a shaft that has a larger gear that engages a worm gear, to a shaft with a universal joint.
He claimed that this was added later t drive an auxiliary oil pump to lube the engine. I disagreed, pointing out that, one of the reasons you use a worm drive is so that it can't be back driven, as he was describing. additionally, let's assume that the flywheel is 20' in dia, and the small gear is 1.0' in dia (it was actually smaller) at an engine speed of 50 RPM, the shaft would be turning 1000 RPM. Not even taking into account the next gear and worm (if it could be driven) the final shaft would be flying.
Looking at the lack of and substantial bearings on the shafts, I wasn't buying it.
I believe what it really was for was barring the engine with either an axillary engine as is quite common or an electric motor, later in it's life.
The designer did put in a method of barring the engine originally (not using the flywheel), but you had to clime up on top of the engine and spin, essentially, a ship's wheel.

[crueby]

Hi Sid,
I really want to get back there on a day when I can take that extended tour! Unfortunately I could only be there Friday when it was not offered, hoping to be there a day it is next time.

I agree with you on that worm gear - no way at all it could drive a pump from the flywheel, you can't backdrive a worm gear as the docent claimed, that looks like an add-on for a motor they may have used to drive the flywheel around for demos after it was out of service - it also has no way to disengage it like a normal barring setup would.  When I was talking to the director there he mentioned at one point that they would like to set up the Allis engine to be driven by an electric motor for demonstrations.
Glad you were able to get in there, it is a very nice museum, great to have the several different types of engines all together.
Chris

[sid pileski]

Chris- I thought about the demo thing too, but in their info and history of the engines, it was never mentioned that these were anything more than working engines.
When they were put out of service, that was it. Now, this particular engine, as you and they pointed out was troublesome and I think was off line when the Allis and Worthington were working. So maybe it was a demo drive.
I should have looked closer, but I don't think that gear was engaged to the flywheel.
BTW, down below, there is another single  vertical engine that they used for generating electricity. Between the Worthington and Allis is the remains of a switch panel.
They thought it was probably DC generated. (in that time period, probably).

Sid

[crueby]

Chris- I thought about the demo thing too, but in their info and history of the engines, it was never mentioned that these were anything more than working engines.
When they were put out of service, that was it. Now, this particular engine, as you and they pointed out was troublesome and I think was off line when the Allis and Worthington were working. So maybe it was a demo drive.
I should have looked closer, but I don't think that gear was engaged to the flywheel.
BTW, down below, there is another single  vertical engine that they used for generating electricity. Between the Worthington and Allis is the remains of a switch panel.
They thought it was probably DC generated. (in that time period, probably).

Sid

In your picture it looks like the small gear on the shaft holding the larger worm gear is engaged with the openings in the flywheel - or is there a space between? Or is that not the flywheel?


I didn't notice the other single vertical engine - I was so busy gawping at the big ones that I must have missed it! Did you get a picture of it?

[sid pileski]

Chris- that is one of the flywheels. I did not get a better picture. I can't tell from my own photo if it was engaged or not, but I didn't think it was.
The generator engine was below on the pump level. So, you would not see it if you did not do the tour to the "basement".

Sid

[crueby]

Chris- that is one of the flywheels. I did not get a better picture. I can't tell from my own photo if it was engaged or not, but I didn't think it was.
The generator engine was below on the pump level. So, you would not see it if you did not do the tour to the "basement".

Sid

Gotcha!  One more reason to get back there for the better tour. I should be going up to Maine again this fall for the logging museum fall event (looks like that may happen this year), and may be able to work in a trip up to the old logging camp/locomotives way up north with a couple guys from the  museum. If so, maybe I can work out the trip so I can hit the waterworks museum on a Wednesday when they have the special tours - the logging event would be on the saturday and sunday so those tour days are out. Have to see what the fall tour schedule is, they dont have anything in the fall posted on their website schedule yet.

[crueby]

And got started on cutting the ends of the center opening through the bed plates - this should be the last operation for these parts on the rotary table. I used a small end mill to give the inside corners a small radius, which meant that I had to finish the cuts from the other side of the plates.

Two plates up to this point, one more to go...