Author Topic: A vertical steam pump. (Read 1480 times)

Michael S. · « **on:** June 18, 2026, 09:50:30 pm »

Not long ago, Sanjay asked me if I was familiar with Torsten Schuer’s vertical steam pump and whether the castings were still available. I checked with T.S. Modellbau and found out that castings for the pump are being produced again.
However, I also recalled that the exact same pump appears in a Dutch book on model steam engines as a project with plans—and that was a pump I had always wanted to build. The only thing I had been missing was the piece of steel T-section required for the stand; in this version, the pump isn't built using castings.
Now I have that T-section in my hands, and construction of the pump can begin.
To start with, it’s purely manual work—sawing, filing, and drilling. Just the sort of thing I enjoy. I marked out the dimensions for the stand and got to work. Now I’m holding the stand, cut to its outer dimensions.

Michael

crueby · « **Reply #1 on:** June 18, 2026, 09:52:15 pm »

Looking forward to seeing it come together!

JackPick · « **Reply #2 on:** June 19, 2026, 03:55:53 am »

Off to a good start. I like it!

Jasonb · « **Reply #3 on:** June 19, 2026, 07:06:29 am »

Off to a good start. Was it just a freelance design or is it based on an actual older pump?

It's a very similar design to one I made some time ago, I just used two separate pieces of steel to form the "T"

https://www.modelenginemaker.com/index.php?topic=11075.0

Michael S. · « **Reply #4 on:** June 19, 2026, 09:03:18 am »

Thanks, everyone.

Jason, I’m actually familiar with this design from fire engine steam engines; I’ve often seen this type of slotted crosshead there.
The drawing and construction instructions come from the Dutch book *Handbuch Modelldampfmaschinen* (Model Steam Engine Handbook).
It’s a good book—especially for beginners.

Michael

Michael S. · « **Reply #5 on:** June 19, 2026, 06:37:57 pm »

Next up is the base plate, made from 8 mm sheet steel with four mounting holes. Small raised sections are added around the four holes to give it a cast-metal appearance.
The crankshaft requires a bearing bushing; a 15 mm steel tube was fabricated and joined using silver solder.
After that, a cutout needs to be machined to accommodate the eccentric.

Regards, Michael

Sanjay F · « **Reply #6 on:** June 19, 2026, 06:53:21 pm »

Quote from: Michael S. on June 19, 2026, 09:03:18 am

Thanks, everyone.

Jason, I’m actually familiar with this design from fire engine steam engines; I’ve often seen this type of slotted crosshead there.
The drawing and construction instructions come from the Dutch book *Handbuch Modelldampfmaschinen* (Model Steam Engine Handbook).
It’s a good book—especially for beginners.

Michael

The engine on the front cover does not look like a beginners engine, if it is, I must be way underqualified to call myself a beginner!

Michael S. · « **Reply #7 on:** June 19, 2026, 07:26:47 pm »

The stand still requires a top and a bottom plate—one to serve as the base and the other at the top for the cylinder.
The parts are attached with screws and then soldered using soft solder.
The large base plate was also stamped on the underside so that people will know later who built it and when.

Michael

Michael S. · « **Reply #8 on:** June 19, 2026, 07:43:11 pm »

Hi Sanjay, the book does include simple construction plans, and it explains a great deal about steam engine valve gear, boiler construction, locomotives, portable engines, steamrollers, and workshop techniques.

Michael S. · « **Reply #9 on:** June 20, 2026, 10:31:45 am »

The flywheel was turned from a 70 mm piece of steel. For the bearing bushings, I am using off-the-shelf bronze ones; three of them fit into the bearing sleeve. Only the outer diameter needs to be reduced slightly. The bronze bearings are simply press-fitted in. And finally, there is the crank disc; it, too, is simply press-fitted onto the 8 mm crankshaft.

Michael

Sanjay F · « **Reply #10 on:** June 20, 2026, 04:04:56 pm »

It's really starting to come together now, very nice work!

Michael S. · « **Reply #11 on:** June 21, 2026, 06:55:03 pm »

Thank you Sanjay.

The cylinder came from the scrap bin and is 2 mm longer than required. However, I’m leaving it at that length and making the piston slightly longer instead.
The valve chest and valve are finished, too. Then I noticed a mistake: I had misinterpreted a dimension, resulting in the crankshaft sitting 4.5 mm too high and the crank being too close to the cylinder. I fabricated a ring—featuring a rounded outer edge so it wouldn't be too conspicuous—to address this. The piston is finished now as well.

Michael

Michael S. · « **Reply #12 on:** June 21, 2026, 07:07:26 pm »

I’m having trouble uploading 8 images. For the past few days, I’ve only been able to upload a single image along with my text. If I try to upload two images—or all 8 at once—nothing happens, and the upload stalls. I have to cancel the process and upload each additional image individually by editing the post. Could it be an issue with my smartphone?

Michael

Sanjay F · « **Reply #13 on:** June 21, 2026, 07:59:14 pm »

I really like the rectantagular but curved gland on the steam chest, how did you make that, was it by filing only?

Michael S. · « **Reply #14 on:** June 21, 2026, 08:15:24 pm »

Hi Sanjay, I initially machined the stuffing box in several stages, but then finished it with a file. It was supposed to look more concave, but I liked the way it turned out this way.

crueby · « **Reply #15 on:** June 21, 2026, 08:19:44 pm »

The ring looks good - more like a fancy casting detail.

Michael S. · « **Reply #16 on:** June 22, 2026, 08:31:16 pm »

Thank you Chris,

The next step was fabricating the crosshead. First, I marked out all the dimensions; then, I drilled the center before milling it out. Creating a perfectly parallel slot was not easy. The entire part required a combination of sawing, milling, and filing.

Michael S. · « **Reply #17 on:** June 22, 2026, 08:46:39 pm »

After grinding the curves on the belt sander and smoothing them with a file, the part went back onto the lathe for the ends to be machined. The bronze sliding block was fitted and test-mounted. To perform a final test, I had to manufacture and install the pump piston and pump body.

Michael

https://youtube.com/shorts/Wt0D-uCmT1A?is=0O0fcMN8KT7lhPFD

Sanjay F · « **Reply #18 on:** June 22, 2026, 09:01:30 pm »

Looking great and have you much more to go before it's running?

crueby · « **Reply #19 on:** June 22, 2026, 09:09:09 pm »

Looks great, moving very smoothly, should be running well soon!

Michael S. · « **Reply #20 on:** June 22, 2026, 09:15:32 pm »

Many thanks, Sanjay and Chris.
Today, I started drilling a number of holes in the pump block. According to the plans, the pump doesn't use balls for the valves; I have to fabricate valves that need to be lapped in.

propforward · « **Reply #21 on:** June 22, 2026, 10:04:49 pm »

I just watched the video showing you turning it over by hand. Excellent workmanship!

Kim · « **Reply #22 on:** June 22, 2026, 10:48:11 pm »

That is very nicely done, Michael!

Kim

cnr6400 · « **Reply #23 on:** June 23, 2026, 02:37:49 am »

Great job Michael! I predict things will be getting sprayed with water soon...

Michael S. · « **Reply #24 on:** June 27, 2026, 07:58:08 pm »

Thank you,

It was a very hot day today—41 degrees Celsius.
However, it was bearable in the workshop, and I was able to fit the pump block with a few flanges and covers. I am using O-rings instead of flat gaskets for the valve covers. The block isn't finished yet, though; the air tank and a pressure relief valve are still missing.

Michael

Sanjay F · « **Reply #25 on:** June 27, 2026, 08:02:59 pm »

41 degrees and there's us complaining in the UK!

Well things have progressed in the workshop and your pump looks like its glowing in the setting sun

This one going to be an impressive working pump and work of art when completed

Michael S. · « **Reply #26 on:** June 27, 2026, 08:42:27 pm »

Thanks, Sanjay,

The intense heat is getting unpleasant.

Michael

crueby · « **Reply #27 on:** June 27, 2026, 08:45:21 pm »

Crazy high heat in Europe this week! Drink plenty of water. If you stop sweating in that kind of heat, get more water!

PaulR · « **Reply #28 on:** June 27, 2026, 08:50:56 pm »

Looks great Michael. In the first photo in reply 17 where you put the yoke back in the lathe to do the ends, is it just held by pressure against the piece of brass hex or is there a screw in there?

Michael S. · « **Reply #29 on:** June 27, 2026, 09:00:41 pm »

Thanks Paul,

The crosshead has M5 x 0.5 threads at both the top and the bottom.
The part is screwed onto the hex section.
I have a stock of brass parts with various internal and external threads; they always come in handy for jobs like this.

Michael

Michael S. · « **Reply #30 on:** June 27, 2026, 09:19:54 pm »

Hi Chris,

My two workshop elves and I take the "drinking a lot" part very seriously........Evening workshop meeting......

Michael

crueby · « **Reply #31 on:** June 27, 2026, 09:34:54 pm »

And great taste in drinkables...

Roger B · « **Reply #32 on:** June 28, 2026, 12:55:25 pm »

Prost

Michael S. · « **Reply #33 on:** June 28, 2026, 07:19:58 pm »

Today I worked on a few parts for the pump.
I made an air vessel—also known as an air chamber. The pressure relief valve isn't being mounted on top of the air chamber, as called for in the plans, but rather on the valve cover. I fabricated a valve for this purpose.

Best regards, Michael

Sanjay F · « **Reply #34 on:** June 28, 2026, 07:38:49 pm »

Hiw did you get the copper colour on the brass air vessel? Looks really nice with the tap on top

Michael S. · « **Reply #35 on:** June 28, 2026, 07:58:59 pm »

Hello Sanjay, that is a 15 mm copper pipe. It is soldered to the brass caps using silver solder.

Sanjay F · « **Reply #36 on:** June 28, 2026, 08:27:57 pm »

It looked like the copper and brass had blended together hence my question

crueby · « **Reply #37 on:** June 28, 2026, 08:29:28 pm »

Wonderful little valve - I like how you drilled the hole in the valve stem. Here in the US the pump manufacturers called that a 'force chamber', to take up the pressure waves from the pump motion and keep them from hammering the water pipes downstream.

PaulR · « **Reply #38 on:** June 28, 2026, 10:40:18 pm »

Quote from: Michael S. on June 27, 2026, 09:00:41 pm

I have a stock of brass parts with various internal and external threads; they always come in handy for jobs like this.

I'm gradually acquiring a bunch of these 'widgets' as well, at the minute they're all living in one drawer, I really need to separate and label them.

Michael S. · « **Reply #39 on:** July 04, 2026, 09:34:14 pm »

Over the last few days, I managed to make a few more valves and an oil reservoir with a valve. I wanted to bend the handle on the oil reservoir's valve; I know this has to be done very slowly, but it snapped off anyway. This was likely because the handle was too short and the brass material was too brittle.
I was able to reattach it using silver solder.
Three drain valves were also produced; they feature an M5 x 0.5 thread at the end for connecting a pipe.
Now all the holes in the cylinder and valve chest are sealed, and I could start working on the eccentric.

Michael

crueby · « **Reply #40 on:** July 04, 2026, 09:47:33 pm »

Fantastic work!

Kim · « **Reply #41 on:** July 04, 2026, 09:51:01 pm »

Those are the cutest little valves! Nice work, Michael!

Kim

Sanjay F · « **Reply #42 on:** July 04, 2026, 09:52:27 pm »

Yeah I agree, they look great, well done, its looking better day by day, post by post

Michael S. · « **Reply #43 on:** July 05, 2026, 08:27:47 pm »

Thanks Chris, Kim and Sanjay

Today was eccentric day. The weather bears no resemblance to July, and the climate in the workshop is perfect.
I still need to make the connection to the valve rods.

Michael

Sanjay F · « **Reply #44 on:** July 05, 2026, 09:45:42 pm »

Everyday is an eccentric day in our household .......according to my wife!

Its definitely getting there, not long and we'll be able to see some pumping

Michael S. · « **Reply #45 on:** July 07, 2026, 07:47:02 pm »

I’ve finished the connecting rod between the eccentric and the slide valve. I was curious to see if the pump would turn when I pressed the compressed air hose against the inlet. The joint currently uses just a simple M2 screw; that will be changed later. The pump valves are also still missing.

Michae

https://youtube.com/shorts/T8Qknv03bMw?is=euOearGT2D5MOuV5l

The initial test run was performed without seals on the cylinder or stuffing box. The piston does not yet have a piston ring, and the slide valve was only roughly adjusted. Still, I am pleased that the engine turns.
Now, everything is being disassembled, and the iron parts are being painted.

crueby · « **Reply #46 on:** July 07, 2026, 08:17:19 pm »

Even without those last parts and the seals, its running very well!!

Sanjay F · « **Reply #47 on:** July 07, 2026, 08:25:30 pm »

It looks gorgeous and runs great without all the seals etc. You've really made something special there, congratulations

PaulR · « **Reply #48 on:** July 08, 2026, 08:19:38 pm »

That's a beauty Michael and what a smooth runner already!

Roger B · « **Reply #49 on:** July 09, 2026, 10:26:49 am »

Looking good

I've always liked scotch yoke engines

Michael S. · « **Reply #50 on:** July 09, 2026, 11:14:40 am »

Thank you, Chris, Sanjay, Paul and Roger.

Michael S. · « **Reply #51 on:** July 12, 2026, 06:42:14 pm »

Some small progress has been made on the steam pump. The parts to be painted are currently with the painter.
While the parts are drying, I’ve fabricated a simple main valve and a T-fitting with a displacement lubricator. All that’s missing now are the valves for the water pump. So, there’s still a bit of work to do.

Michael

Sanjay F · « **Reply #52 on:** July 12, 2026, 07:57:39 pm »

Its the small details which make the difference and you certainly have them

crueby · « **Reply #53 on:** July 12, 2026, 07:59:59 pm »

I really like the shapes on the valves.

Michael S. · « **Reply #54 on:** July 16, 2026, 08:19:08 pm »

The cylinder sheet is finished—this time made of copper.
Since copper darkens quickly, I used a copper/brass patina solution to help the process along.

Michael

cnr6400 · « **Reply #55 on:** July 18, 2026, 05:23:51 pm »

crueby · « **Reply #56 on:** July 18, 2026, 06:37:26 pm »

The patina solution gave it a great color.

Michael S. · « **Reply #57 on:** July 19, 2026, 05:57:30 pm »

#Invalid YouTube Link#Today I made the two valves for the water pump and then lapped them with fine polishing compound.

I even had time to test with water.

https://youtube.com/shorts/dAwTKqKB29c?is=UwcseQsezHoW0Kwz

crueby · « **Reply #58 on:** July 19, 2026, 06:21:46 pm »

Do the valves have springs holding them down, or is it just their own weight?

Michael S. · « **Reply #59 on:** July 19, 2026, 06:32:45 pm »

Hi Chris, no springs.
The plans don't call for any springs. It looks like it works. I’m not sure which is better, though—ball valves or cone valves, with or without springs.
In any case, this is my first pump using these types of valves.

Michael

Michael S. · « **Reply #60 on:** July 26, 2026, 06:38:11 pm »

Hello everyone,

The steam pump is now finished.

It was fun building the pump. I think the green color suits pumps well.

Michael

<a href="https://www.youtube.com/watch?v=EJwsfkTFYnU" target="_blank">http://www.youtube.com/watch?v=EJwsfkTFYnU</a>

Sanjay F · « **Reply #61 on:** July 26, 2026, 06:49:12 pm »

A stunning piece of work made from scratch; it looks amazing, sounds great chugging away. All the little detailed components you have fabricated have added so much to the overall look

Michael S. · « **Reply #62 on:** July 26, 2026, 06:55:45 pm »

Thank you very much, Sanjay.

crueby · « **Reply #63 on:** July 26, 2026, 09:02:16 pm »

Terrific! Works and sounds great, the green sets off the metal very well. Your shop elf/engineer seems very happy with it too.

cnr6400 · « **Reply #64 on:** July 26, 2026, 09:07:40 pm »

Great running pump Michael, and looks excellent too. Congratulations on the new shop staff as well.

Kim · « **Reply #65 on:** July 26, 2026, 10:26:14 pm »

Runs great, and looks great! Wonderful job, Michael!

Kim

Dave Otto · « **Reply #66 on:** July 26, 2026, 11:23:14 pm »

That turned out really nice Michael!

Dave

Admiral_dk · « **Reply #67 on:** July 27, 2026, 06:50:35 am »

Beautiful result, the Pump looks magnificent, run well

Per

wagnmkr · « **Reply #68 on:** July 27, 2026, 11:40:34 am »

Another excellent engine to go in your display. Runs well and looks great!!

Tom

Michael S. · « **Reply #69 on:** July 27, 2026, 07:03:39 pm »

Thanks, everyone, for the kind words.
Maybe I'll test them with steam sometime.

Michael

crueby · « **Reply #70 on:** July 27, 2026, 08:26:38 pm »

It would be interesting to see how far the water will jet from a small nozzle at higher pressure.

Michael S. · « **Reply #71 on:** July 27, 2026, 08:39:49 pm »

I also think this pump is better suited for use as a fire pump; it is not well-suited for filling a steam boiler.
The old fire pumps have that slotted crosshead.

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Author Topic: A vertical steam pump. (Read 1480 times)