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Gallery, Projects and General => Project Logs => Topic started by: sbwhart on April 10, 2011, 12:33:25 PM

Title: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 10, 2011, 12:33:25 PM
A friend and fellow madmodder asked if I could help out and build a boiler feed pump for him.

The pump comes as a kit of casting complete with a set of very clear drawings from :- Southworth Engines, 6 Kennet Vale, Chesterfield, S40 4EW England.

The phosphor bronze castings seem to be good quality, but if you prefer the engine could be made from bar stock.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0004.jpg)

I've positioned the castings so that I don't give too much away on the drawings and have the copy right police onto me.

Starting with the cylinder casting first clean the port face off just enough to give a flat face, square the ends off taking again just enough off to get things square and to have a clean surface to work with.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0007.jpg)

Then mark out and center pop the bore position.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0009.jpg)

In the independent four jaw chuck and using a wobble bare get the bore on centre.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0010.jpg)

Nice deap centre drill then pilot drill followed by a 12.5 mm roughing drill.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0013.jpg)

Finish to size with an 1/2" hand reamer.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0012.jpg)

Next turn up a mandrel that a nice slide on the bore.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0016.jpg)

Wrap a bit of thin paper (fag paper) round the mandrel, and push the cylinder onto the mandrel so that it grips enough to get a drive and face both ends of the cylinder to length, this way you are sure that the faces are square to the bore.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0015.jpg)

The mandrel will be now used to mount the cylinder onto an angle plate so that you can mill the valve face off perfectly parallel to the bore.

This is it mounted up and marked up so the valve face can be milled to size.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0017.jpg)

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 10, 2011, 01:02:33 PM
I am very glad that you have taking this projet, I have thinking about this boilerpump.
Nice work.  :thumbup:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: lordedmond on April 13, 2011, 02:45:10 AM
Stew


nice work

what with your pussy faux pas now we have "fag" paper  :doh: what will our friends across the pond think "gay paper"  :jaw:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 13, 2011, 12:55:24 PM
Cheers Chaps

Bit more done today the Boss is away visiting a friend:-so I got all day in the shed  :D

On with the cylinder

With it mounted on the mandrel and angle plate fly cut port face to size nice and square to the bore.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0018.jpg)

Drill the ports and the clamping holes for the steam chest

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0021.jpg)

Tap the steam chest holes nice and square

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0022.jpg)

Then using a coaxial indicator centre the mill on the bore and drill the stud holes and connect up the port holes using a tickle wire to indicate when the holes join up.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0023.jpg)

This machines cylinder

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0029.jpg)

The port face plate, the steam chest cover and cylinder cover are cut from this one phosphor bronze casting.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0030.jpg)

Fly cut the face and square the edges up and cut them out.

Then drill the port face plate this has a similar hole arrangement to the cylinder but with more holes.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0032.jpg)

Then using a 1/6" burr join up the exhaust ports

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0039.jpg)

This is what it looks like completed.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0040.jpg)

Piston and steam chest cover yet more drilling work so not showing pics.

Steam chest is yet another casting, so again clean and square it up and mill it to size drill holes and mill out the middle for the slide valves.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0041.jpg)

These are the bits completed so far

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0043.jpg)

And lose assembly

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0044.jpg)

Stew
 
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Bogstandard on April 13, 2011, 02:22:09 PM
Coming along very nicely Stew.

I especially like the way you are using the mill for most of the work.

People seem to think that it should all be faceplate and four jaw work on the lathe, but like yourself, I find things like that a lot easier and quicker to do on the mill, with only basic set up requirements.


John
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 13, 2011, 03:08:56 PM
I just love your'e work, the only thing I wish for is that you could have a little bigger picture, it's little hard to see every fine work you are doing.  :dremel:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 13, 2011, 03:38:51 PM
Thanks John

Saw I'll post bigger pics next time.

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 13, 2011, 04:04:52 PM
Thanks Steve, no hard feeling but I learn so much from you so I will not miss it.  :thumbup:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 13, 2011, 04:20:21 PM
Thanks Steve, no hard feeling but I learn so much from you so I will not miss it.  :thumbup:

No hard feelings at all, just pleased to help and nice to know you find the posts informative.

 :thumbup:

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: madjackghengis on April 14, 2011, 08:23:21 AM
By the way Stew, no worries here from the colonies, I've been putting in plenty of pics with cigarette papers, and we're politically correct to know that you'd be calling them lgbtqw papers if you were refering to gay papers.  Every one knows a fag is a smoke, don't they?  Very nice set of castings, very nice work in milling out those passages, and lining everything up, this is an informative build, at least for me.  Cheers,  :beer: Jack
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 15, 2011, 04:56:23 AM
Thanks Jack

I always find it interesting how people who share a common language use words in a different way it can certainly land you in trouble. I often wonder what you Guys think of us limeys when we start chattering away to each other using strange words and with dialect spelling, you must think we've invented an all new language.

On with the job in hand then:-

Piston and piston rod:-the piston rod doubles as the pump rod, this will become clear in time, its made from 1/4" stainless steel. Turn down one end and tap M5 and undercut the thread so that the piston screws down square and cut it off to length.


This it being under cut

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0045.jpg)

The engine calls for a silicone piston ring, to ensure that you fit this ring correctly measure the cylinder bore accurately, and the thickness of the O ring and work out the diameter of the groove to give the ring about 10% compression and the diameter over the un compressed ring.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0050.jpg)

Grind up a grooving tool the width of the ring.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0051.jpg)

I used a bit of stainless steel hex as this was the only material I had big enough to get the piston out of, turn it up to the diameter of the uncompressed ring. Then cut the groove to the full depth of the ring.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0052.jpg)

Then stick the roughed out piston to the rod with stud loc.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0055.jpg)

Then mount the assembly in a collet and turn the piston down to a nice slide fit in the cylinder.

This way the piston and rod will be concentric.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0056.jpg)

Fit the O ring

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0062.jpg)

It should be a nice slide fit into the cylinder:-be careful you don,t end up pinching the ring on any sharp edges in the cylinder scrape them off.

Next bit the bottom cylinder cover.

This is the casting

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0063.jpg)

First turn the chucking piece up to get a clean diameter

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0064.jpg)

Turn it round face and drill and bore out the pocket for the sealing ring.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0065.jpg)

Back face to thickness

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0066.jpg)

Then over to the spin indexer mark out the fancy shape.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0069.jpg)

and mill it out

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0072.jpg)

Then over to the RT clock the bore central to the mill spindle, rotate RT so that the holes are drilled in the correct orientation.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0075.jpg)

This sequence of shots shows the advantage of having a tooling system based on one collet system in this case ER32.

Back onto the lathe and part it off.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0081.jpg)

At this point I realized that there was something wrong with the drawing/design as drawn the pocket for the sealing ring is too deep the closing disc won't compress the ring to give the seal, so Instead of having a plane disc as drawn I made the disc with a small boss that will sit into the pocket and compress the ring.

Her are the bits

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0085.jpg)

And assembled

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0088.jpg)

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 15, 2011, 05:07:51 AM
Just wunderfull, tanks for bigger picture.  :D :thumbup: :clap:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on April 15, 2011, 07:56:25 AM
Stew.
I love the way you work, and the work you produce.  :clap: :clap:

Watching/ enjoying, quietly......  :thumbup:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: madjackghengis on April 15, 2011, 10:40:57 AM
Hi Stew, I too enjoy the word interplay with our cousins across the pond, it is interesting, and having spent time in the Marines, and visited a few Brit ships, it is easy to enjoy the close relationship we have.  You stated the value of having many tools using the same collet system and I was just going to comment on how handy that must be, it has worked very well in this build, and you've shown some very fine bits and pieces, nicely done.  I definitely envy your set of collets :lol:, at some point I will have to invest.  Very nice pictures and explanations, fine craftsmanship all the way. :beer:  Cheers, Jack
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 16, 2011, 03:03:08 PM
No problem Saw my pleasure.

Thanks Dave

Cheers Jack:- John first showed me the benefits of having a tooling system and I took full advantage of it.

Top pump cover yet another casting this time it odd shape meant I couldn't grip it to clean up the cucking piece, so this time I grip the chucking piece got things running true as best as I could then cleaned up as much of it as I could using the long reach of a parting tool then parted it off so that a I had a sorter but clean bit to grip onto.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0092.jpg)

It was then just a mater of dealing with it in the same way as the cylinder bottom cover.

For those who have not seen one of these this is the coaxial indicator I use to centre the job under the mill.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0100.jpg)

To drill the holes around a pitch circle I use the PCD feature on my DRO it's a lot easier than using the RT to index.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0104.jpg)

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0105.jpg)

This is the finished part after a tidy up with a file.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0107.jpg)

Pump Body:-this casting was a bit lean on material so had to be carful with it, bit of an odd shape to deal with.

First clean up the main body diameter and face off just enough to give a clean register to work with.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0109.jpg)

Mark it out checking that everything will come out in the correct position with enough material around it.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0111.jpg)

Back onto the lathe face off to the mark clean the other dia up and drill out the pump chamber.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0115.jpg)

Again in the lathe just clean a whisper off the clack valve extensions, getting them running as true as I can.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0116.jpg)

Turn up a mandrel to locate on the pump chamber diameter, mount this in the spin-indexer.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0117.jpg)

Pick up the centre of the mandrel using a wobbler.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0118.jpg)

Set the casting up level using the height gauge (my indexer has a centre height of 70mm)

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0119.jpg)

And mark it out using the indexer and height gauge.

Then machine the arms to length and drill the valve chamber.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0121.jpg)

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0122.jpg)

Tap

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0123.jpg)


Finished Job

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0124.jpg)

I then turned up the pillar supports sorry no pics simple turning job.

And this is the assembly so far

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0127.jpg)

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Bogstandard on April 16, 2011, 03:33:01 PM
Looking absolutely great Stew.


John
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Brass_Machine on April 16, 2011, 07:43:42 PM
Wow Stew... That looks very nice!  :bow:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 17, 2011, 09:14:14 AM
Cheers  Guys

Two more bits ticked off this morning.

Pump body bottom cover and activation lever.:- more of the same really so no making pics.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0128.jpg)

And in the assembly

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0129.jpg)

Couple of more days and we shall see if it will work.

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 17, 2011, 11:05:49 AM
Looking very good  :clap: :clap:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Divided he ad on April 17, 2011, 07:07:57 PM
Missed this lot over the last few days Stew. With the site re-locating and all.

Very happy that John looked at this thread when I was there this afternoon.... Came home and read through the whole thread and very glad I did.... A little gold mine of mounting and machining tips.... Very much liking the "tickle wire"  :lol:  So simple but so very useful to remember  :thumbup:




Very nice work and well shown. Happier about the new picture size too  :thumbup:







Ralph.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on April 18, 2011, 01:53:32 AM

Couple of more days and we shall see if it will work.
Stew

If component quality and looks are anything to go by...... It will work. Splendidly!  :thumbup:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 18, 2011, 03:50:37 PM
Thanks very much Guys your support is much appreciated   :headbang:

Got few more bits done today:- valve rod stops, steam chest covers and made a good start on the slide valves mainly drilling work I'll post some pics tomorrow.

Had a good bit of customer service to day from an ebay trader, I order a length of 1/16 stainless steal for the valve rod, it came very quick but when I tried it in the engine I found they had sent me 3/32, so contacted the seller pointing out their mistake, this morning what should land on the doorstep but two length of 1/16 bar, so sent them a mail asking if they wanted the 3/32 bar returning:-no they said were very sorry for the inconvenience.

This is the company http://stores.ebay.co.uk/CLIPS-BITS?_trksid=p4340.l2563

 :D :D :D :D :D

Stew


Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on April 19, 2011, 02:21:51 AM
Thanks for the link Stew!

I've just ordered the Robinson displacer shaft.  :thumbup:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 19, 2011, 12:42:24 PM
Not much shed time today as we were looking after grandson it's amazing how quick they grow that sounds stupid having had two kids of our own, but I seem to notice his development more, mind you I was too busily putting bread on the table when our own were growing up.

Completed some small parts:-

Slide valves, valve rod stops, and steam chest end covers.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/IMG_3218.jpg)

To mill the slots in the slide valves I used a 1/16 tungsten burr it did the job well.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/IMG_3204.jpg)

This is how the two slide valves fit in the steam chestengine the inlet is driven by a valve rod and the exhaust is driven by a spool valve activated by back pressure in the cylinder. (I've got to make the spool)

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/IMG_3206.jpg)

Stew

 
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 19, 2011, 12:55:24 PM
I'll think I must build this steam pump sone...  :D
You are building this pump very nice and it's so very easy to folow you, thank you.  :headbang:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: arnoldb on April 19, 2011, 03:59:53 PM
Good going Stew  :thumbup: - great job so far!

I see you finally got around to 2mm or smaller screws  :lol:

 :beer:, Arnold
Title: Re: Southworth Engines Boiler Feed Pump
Post by: madjackghengis on April 19, 2011, 08:44:57 PM
Hi Stew, I haven't been able to follow this thread for a couple of days, and you've done some very fine work.  Your attention to detail is apparent in every little bit you make.  I'm getting a real education on this build log.  I've long wanted to see the inside of one of those pumps, and you show it off very well.  It is gorgeous looking as you build it.   :beer:  Cheers, Jack
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 20, 2011, 01:55:50 PM
Thanks a lot Lads

Little more today

Made the spool valve, from 4mm stainless steel you make it like a dumbell the middle bit is only 1/16 dia so it need some suport from a centre, I made it over length for the centre and faced the centre out to get the correct length.

(http://i431.photobucket.com/albums/qq32/sbwhart/131_0132.jpg)


(http://i431.photobucket.com/albums/qq32/sbwhart/131_0137.jpg)

And how it fits in the engine the inlet valve is activated by the valve rod the exhaust valve from the back pressure in the cylinder moving the spool valve.

(http://i431.photobucket.com/albums/qq32/sbwhart/131_0147.jpg)

Just the clack valves in the pump to finish off and a final assembly then we can see if she will pump water.

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Bogstandard on April 20, 2011, 04:36:42 PM
I got to get my grubby gorilla fingers on this beauty this afternoon, when Stew called in for a gum beating session.

If it runs as well as Stew has made it, it will be a stunner.

Stew makes light of the machining part of this project. It is in fact a very precise machining exercise, like a steam powered swiss watch.

Very well engineered Stew, a real credit to your skills.


John
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 22, 2011, 01:19:02 AM
Thank you very much John much appreciated.

Well I lost round one at getting to work, took me ages to get my head round how to set the timing at last I figured out that due to the rod stops and the configuration of the steam way that it work back to front to a more conventional slide valve set up, when I eventually got it sorted and subjected it to air found that I'd got a huge air leak from the bottom steam chest cover. At that point decided I needed a cuppa and a bit of cogitation time.

Round two start this morning

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on April 22, 2011, 01:43:43 AM

Round two start this morning

Stew

Today's the day......   :smart:

Good luck Mate!  :thumbup:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 22, 2011, 04:30:55 AM
Got it running  :D :D :D :D

Bigest problem getting a seal arround the steam chest.

I'll run it for an hour before trying the pump, I'll post a vid with the pump running (fingers crossed)

 :thumbup:


Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 22, 2011, 08:30:00 AM
Her we go



 :D :D :D :D


Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Bogstandard on April 22, 2011, 08:34:44 AM
Stew,

Great.

N'uff said.


John
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Rob.Wilson on April 22, 2011, 09:46:50 AM
 :clap: :clap: :clap: :clap: :clap: nicely done Stew  :bow: :bow: :bow:

Interesting project


Rob 
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on April 22, 2011, 12:00:51 PM
Big smile time again.....  :ddb: :ddb:

Very well done Stew!  :clap: :clap:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: arnoldb on April 22, 2011, 03:41:44 PM
 :clap: :clap: Good going Stew  :thumbup:

 :beer:, Arnold
Title: Re: Southworth Engines Boiler Feed Pump
Post by: saw on April 22, 2011, 04:34:15 PM
Nice I just love it  :clap: :clap: :clap:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: ozzie46 on April 22, 2011, 06:01:44 PM

   Great job Stew.  :bow: :bow:  :beer: :beer:

   Isn't that Colorado Rockies cup a bit far from home.   :scratch: :scratch:  :) :) :)


  Ron
 
  Pueblo Colorado, USA
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 23, 2011, 12:47:50 AM

   Great job Stew.  :bow: :bow:  :beer: :beer:

   Isn't that Colorado Rockies cup a bit far from home.   :scratch: :scratch:  :) :) :)


  Ron
  
  Pueblo Colorado, USA


Yes, it is, visited my wives cousin who's a Minister at a Denver Church a few years ago, our Daughter saved the cups from a baseball game we went to, I now use them in my shed for the odd wet jobs.

Thanks for your comments Chaps

Stew

Title: Re: Southworth Engines Boiler Feed Pump
Post by: Bogstandard on April 23, 2011, 01:43:49 AM
A gang of us (3 actually) gathered in my little shop last night and put this little baby thru it's paces.

First off, I personally couldn't believe how little pressure it required to run. We had it choked down to what we summised as about 2 PSI and it gently nodded away doing it's own thing.

Restarting, even from this very low pressure, it didn't miss one beat, stop it, put tiny pressure to it again, and away it went, just as though it had never stopped.

One of our mottley crew then brought up the question.

This is basically a single cylinder double acting engine, and when used in the context of powering a model as an engine, single cylinder engines are usually shyed away from, purely because once stopped, they are very fickle as to whether they can restart again just by applying pressure. The valving arrangement on this engine seems to have solved this age old problem. That definitely requires a good dose looking at. As far as I can see only one problem exists, you would have no control which way the crank would turn as you restarted.

But anyway, back to this pump.

General consensus all round. A fantastic little unit that does what it was intended to do absolutely perfectly.

Very nicely made Stew. :bow: :bow: :clap: :clap:


Bogs
Title: Re: Southworth Engines Boiler Feed Pump
Post by: lordedmond on April 23, 2011, 02:39:28 AM
Stew

Whats it like when its working against a head ,after all that what it is a boiler feed pump

as you know it should be able to pump to a higher pressure that that it is fed with



Stuart
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 23, 2011, 04:19:30 AM
The gang of three did shake out one small fault:- an air leak arround the steam chest, Johns leak detector (cigaret) traced a number of leak that we fixed by shortening screws that were bottoming out, a bit of Hylomar fixed others but one persisted, that was eventually traced to the little o ring arround the valve rod, the pocket cut into the steam chest for it, was way too small for the ring which was holding off the bottom cover, so this morning I cut the pocket bigger, and made some PTfE gaskets from material that John gave me, this seems to have solved the problem, its now running even better and the pump also seems to be bedding in nicely.

Stuart

I tried elevating the out pipe this morning to give it a head to work against it managed a 10" head no problem, that was the length of the pipe, putting my finger over the pipe, stopped the flow but there was a considerable pressure their, the pump kept on working, and the coupling joints started to leak.

Hope this helps

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: lordedmond on April 23, 2011, 05:15:56 AM
Stew

thanks for the info

with 80 psi steam it should do at least 95psi on the water side

I have seen the LBSC type running ( the one with the two rockers on top ) they do chuff well when under load

they sound nice in the station with the exhaust up the lum under load


Stuart
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 23, 2011, 05:42:50 AM

I have seen the LBSC type running ( the one with the two rockers on top ) they do chuff well when under load

they sound nice in the station with the exhaust up the lum under load


Stuart

Just dug out my copy of "shop, shed and road" is that the pump LBSC calls Duplex Double Acting Feed Pump ?. Looks a very interesting design, you can't help but admire the man.

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: NickG on April 23, 2011, 09:44:20 AM
Wow, very nice work Stew. Yourself and Bogs have recently made machining castings correctly look easy but I know otherwise!  :thumbup:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 23, 2011, 10:12:36 AM
Thanks Nick

I was begining to wonder where you were having not heard from you for some time. I bet that four letter word "work" as kept you away.   :D

Stew

Title: Re: Southworth Engines Boiler Feed Pump
Post by: lordedmond on April 23, 2011, 10:42:04 AM
yes that the one Stew

you can not help but admire the man/woman  but that another story , but a brilliant engineer ,he did a lot to get us where we are today , I wonder what he would have made of the current CNC setups


very good work with the pump BTW
Title: Re: Southworth Engines Boiler Feed Pump
Post by: NickG on April 23, 2011, 01:53:54 PM
Stew,

Kind of, been away a few nights which messes up your whole routines! Then I've been doing some bits and pieces tidying the car up. I'm off for a week now so am hoping to get back in the workshop and finish that 2nd poppin. Got the electric loco to finish then I was going to do an i.c. engine, but I've changed my mind, I either want to do a boiler for mabel or do sweet pea-  I have a professional boiler for that and I think I bought most of the fittings. Decisions decisions!

Nick
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 24, 2011, 01:34:34 AM
Blimey Nick


 
Quote
I'm off for a week now so am hoping to get back in the workshop and finish that 2nd poppin. Got the electric loco to finish then I was going to do an i.c. engine, but I've changed my mind, I either want to do a boiler for mabel or do sweet pea-  I have a professional boiler for that and I think I bought most of the fittings. Decisions decisions!


Sounds like you've got a dose of  :proj:

Sweet pea sounds interesting I've got a project planned for some time in the future that would use a Sweet pea boiler, but first I've got to finish off my own Mabel first.

Have fun  :D

Stew




Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: NickG on April 24, 2011, 02:25:53 AM
I know!  :proj: There's not a great deal left to do on the Poppin and electric loco, just a matter of grabbing the bull by the horns really. I've then got a list on Word that I keep chopping and changing. If I go the Mabel route I'll be asking lots of advice and for a loan of your formers if possible! Our new boiler inspector pretty much condemned the old mabel boiler and probably rightly so, don't think it's worth messing about with. The sweet pea is tempting though as it's a relatively simple engine - there's a lot of parts to make, but probably the most difficult part for a lot of people (boiler) is sat there in a box all done.

Quote
I've got a project planned for some time in the future that would use a Sweet pea boiler
sounds interesting!

Nick
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on April 24, 2011, 05:14:50 AM
No Problem with the Mabel formers I can get them to you via the internal post to you if you want them.

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: madjackghengis on April 24, 2011, 01:08:23 PM
Really great job on the feed pump, Stew, very fine work, and it looks very nice with the castings all in all.  Look forward to seeing it pumping into a boiler, the real test in the end.  I am going to have to go through this log again, and get a better look at that valving, I wished I could've been there to watch with you.  :beer:  Cheers, Jack
Title: Re: Southworth Engines Boiler Feed Pump
Post by: doubletop on August 03, 2013, 05:07:23 AM
Ive just finished making one of these pumps and although this is an old thread I thought we may as well keep all the information together..

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/2-004_zpsfacdc773.jpg)

It looks like its going to do what I need it to, and be able to feed a boiler at 90psi. Here it is running on 20psi air pressure and giving 60-70 psi of water pressure. 0.5 piston and 0.25 ram gives a theoretical pressure gain of 4. With losses Im getting a gain of just over 3 so if I run it at 30psi it looks like it will to the job

[ Invalid YouTube link ]

Stu pointed out some errors on the drawings and I have some more to share. He pointed out the error with part 6 and the bore for the 0 ring was too deep. Its also the wrong diameter. The O rings supplied are 0.25 x 0.375 with 0.625 section. So the easy way is to just bore the hole is a 3/8 slot drill. I found making them 0.060 deep was sufficient that it didnt cause the piston to bind. This applies to parts 6 and 22

The castings are very soft and I blew my valve chest off the cylinder trying to run at 30psi. drilling the holes for the 10ba studs only 0.075 deep is just not enough. However, if the holes for the cylinder ends are drilled at PCD of 0.065 then the holes for the ends caps and the valve chest can be as deep as you like (within reason) as they dont get in each others way. I did mine 0.35 deep. (Spacing to the valve chest is 0.6 and a PCD of 0.650 gives a spacing of 0.403 which mean 0.1 between the hole centers, just enough for 10ba)

This is where the dimensions on part 5 are wrong

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/Part5_zps904b7bf8.jpg)

A 0.5 spacing isnt a PCD of 0.650, radius of 0.325. The 0.5 spacing gives a PCD of 0.707 and the holes will clash with the valve chest holes as they are only 0.05 apart.

 I also did a PowerPoint to show how it works, attached below

Hope that helps somebody

Pete


Title: Re: Southworth Engines Boiler Feed Pump
Post by: tom osselton on August 03, 2013, 01:38:13 PM
Stew


nice work

what with your pussy faux pas now we have "fag" paper  :doh: what will our friends across the pond think "gay paper"  :jaw:

So dandruff would be fairy dust then! !    :bugeye:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: OldMetaller on August 14, 2013, 04:50:41 PM
Hi guys, I'm really glad this old thread has been reopened, as I bought the castings for this feed pump from the new owner of Southworth Engines a year or so ago, and scared myself to death!  Much too complicated for a newbie like me, I thought, but now with this thread, I may just steel myself and have a go at it!

Thanks for such an informative build thread!

Regards,

John.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Stilldrillin on August 14, 2013, 05:12:57 PM
Hi guys, I'm really glad this old thread has been reopened, as I bought the castings for this feed pump from the new owner of Southworth Engines a year or so ago, and scared myself to death!  Much too complicated for a newbie like me, I thought, but now with this thread, I may just steel myself and have a go at it!

Thanks for such an informative build thread!

Regards,

John.

Hello, Young Man!  :wave:

Don't forget, we need a build log. With pictures!  :thumbup:

 :worthless:

David D
Title: Re: Southworth Engines Boiler Feed Pump
Post by: doubletop on August 15, 2013, 05:57:48 AM
John

One point I'm going to make about the approach Stew took to the pump. And this isn't a criticism as there are many ways to skin a cat.

I'm not sure why he drilled the ports this way

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0122.jpg)

When they could have easily been done at this point of the machining process.

(http://i431.photobucket.com/albums/qq32/sbwhart/Southworth%20Boiler%20Feed%20Pump/131_0116.jpg)

A 3mm drill to start, then a 7/32" slot drill, tap the 1/4" x40 thread and finish with a 1/8" reamer and then guaranteed nice sharp and square faces for the valves.

Good luck with the build and let us know how you get on. As I found looking at the kit of parts doesn't get the job done. Everything looks quite small at first but getting stuck in and cutting metal you soon get used to working on this small scale

Pete
Title: Re: Southworth Engines Boiler Feed Pump
Post by: sbwhart on August 15, 2013, 07:37:33 AM
I'm not sure either  :scratch:

 :D

Stew
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Steam Geek on August 22, 2013, 11:55:17 AM
I am in the process of ordering the castings to make up a feed pump for my Achilles, tired of messing around with injectors and want something reliable.

Also a test of how accurate my machining is :bang:
Title: Re: Southworth Engines Boiler Feed Pump
Post by: doubletop on August 25, 2013, 06:33:41 AM
I had this running  fine on air but when the input pressure was raised it would just stop and vent through to the exhaust . That implied to me that one of the two valves were lifting. My first thought was the slide valve as it doesn't have any form of crosshead and the only thing keeping the valve rod in line is the thickness of the valve chest wall. On the bigger version the valve rod extends through the top of the valve chest so I thought I'd give modifying it go. Here's the list of changes I made to the various parts.

#18 Slide Valve nut - make it 1/8" thick and drill 1.6mm rather than tap 10ba. on the top edge drill and tap 10ba for a grub screw to hold the valve rod

#15 Valve Rod -  make 2.5" and 1.8" from one end file a small flat for the grub screw

#17 Slide valve - make 0.1" lateral slot now 0.13"

#2 Valve Chest - repeat valve gland on top face. Remember to offset to the correct side to match the gland on the lower face.

#4,4A Cover top/bottom - make two items 4A note there is a drawing error here the No50 hole isn't on the centre line its offset to match the offset on the valve chest.

You'll need another 1/16" x 3/16" O ring. my kit came with two.

The trickiest bit was the 10ba grub screw as its only 0.1 long.. Rather than trying to put a slot in a 10ba rod. I turned down the head of a countersunk 10ba screw and the threaded the end. It then comes with a ready-made slot.

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/3-012_zps229f22ed.jpg)

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/3-015_zps1f487b8b.jpg)

Heres the valve chest  assembled with the extended valve rod coming out the top of the valve chest.

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/3-023_zpsacd37297.jpg)

As would be expected the slide valve is kept well in line. However on re-assembly and re-test the problem of the venting wasnt resolved. So it had to be a problem with the shuttle valve. Checking it was quite a loose fit and able to lift some way off the port face. If you use the 1/64 hallite gasket as suggested in the plans then the lift is an additional 15thou. Although in an earlier post Id suggested using and anaerobic gasket I found you couldnt guarantee any gasket not oozing in to the valve chest under the shuttle valve. And theres no way to check.

If you look at the attached .pdf file you can see the clearance for the shuttle valve to lift is is 32thou Id suggest both should be no more than 10 thou. That what Ive made mine to be. The 0.090 dimension on part 14 should be 0.115. My pump now behaves itself and Ive fitted to my loco.

(http://i747.photobucket.com/albums/xx112/doubletop/Southworth/3-035_zpsa1723a47.jpg)

And it runs this it it pumping water slowly against 90psi boiler pressure

[ Invalid YouTube link ]

I had it at the track today and it was ticking away happily to itself all afternoon. And was adequately pumping water when I upped the pace

Hope that helps somebody

Pete

Title: Re: Southworth Engines Boiler Feed Pump
Post by: NickG on August 25, 2013, 01:27:42 PM
Thats's great Pete, glad it's working well. Well done.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 11:17:37 AM
I'm gearing up to build the pump this winter during the long Vermont winter The castings and appropriate diameters of stainless steel rod are sitting on the bench and I have spent hours reviewing the postings in this thread so many thanks to all of the contributors. Does anyone have photographs or input on machining the butterfly valves?
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 06:50:44 PM
I'm answering my own question here as I decided to make the butterfly valves. 

Turned the 0.125 dia wing section stem to a length of 0.14 then formed the undercut positioning the parting tool against the shoulder. 
Turned the 45deg valve seat and then cut off last inch of stock which was reversed in chuck, faced and center drilled.
The 0.1 spring mount was then turned to facilitate holding the valve in the rotary table chuck to machine the valve wings after which the waste was cut of and the spring locator stub was filed to length.
 
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 06:56:18 PM
forming undercut
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 06:57:59 PM
Turning valve face
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 07:00:03 PM
Turning spring locator
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 07:01:13 PM
milling valve wings
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 01, 2013, 07:02:45 PM
finished valves
Title: Re: Southworth Engines Boiler Feed Pump
Post by: doubletop on September 16, 2013, 06:12:46 AM
Alan

You made a nice job of those valves. I had a few failed attempts, but that was me trying to be smart and grind the 45deg angles with a diamond disc on my tool an cutter grinder. It seemed like a good idea at the time as I've always had trouble seating home made safety valves. I did it your way in the end and they work fine. I think using a 7/32" slot drill in one operation to cut the valve seats and the tapping size for the 1/4 x 40 threads contributed to the success.
 
Pete
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on September 21, 2013, 11:41:04 PM
Thanks for the compliment. I suspect the degree of surface finish on a valve face my be dependent on the pressure and viscosity of the fluid being contained as well as the dimensions of the transfer passage. You would certainly grind the valve faces for an internal combustion engine where pressures and temperatures are high but the viscosity of the intake air and exhaust gases are low. The water pump valves I made did hold air pressure but in practice any backflow on the intake side probably offers more resistance to flow than the output pressure needed to feed the boiler.     
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on November 11, 2013, 05:56:41 PM
My pump is up and running but I have only run it on air so far. I made liberal changes to thread sizes from those in the design substituting #2-56 for many of the 10 BA locations. Getting BA taps and dies is not easy in the USA with many sizes not being available on this side of the pond. Fortunately I inherited a good collection of BA taps and dies from my father but am still missing some from my collection.   Getting the exhaust valve timing adjusted is certainly a labor of love and start up was initially erratic but I traced that to having been too energetic with polishing the shuttle valve spindle and creating too much clearance for it to hold pressure and move the valve body.  I also had problems with the valves seating and made some changes to the height of the valve body to making it the same thickness as the valve chest with the gasket material providing the working clearance.  As other have commented the exhaust valves floating cross head seemed a trifle sloppy and I extended the 1/16 inch rod through the top of the valve chest to provide better control of the cross head's movement, Thanks to Bob Potter for providing two 1/16 ID O rings with the casting kit. :clap:   

I increased the thickness of  the valve chest top and bottom cover to better allow even compression of the gaskets in those locations.  I also modified the cross head design to accommodate a #2-56 cap screw making it stand proud of the valve chest face and used a thicker back plate with a slot milled to provide a track for the cap screw head to run in. 
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Steam Geek on November 22, 2013, 03:04:34 AM
When you are machining the castings what tollerances are you aiming to achieve ? 2 thou ?
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on November 26, 2013, 09:36:43 PM
Posted video of pump working on air on  YouTube.  Use "alan frost steam boiler pump" as search string to locate.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: dsquire on November 27, 2013, 10:32:49 AM
Alan

Here is the link to your video. This will save the members from having to search for it. Hope you don't mind me putting it in here.

    [ Invalid YouTube link ]

Cheers  :beer:

Don
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Doc on November 28, 2013, 10:17:49 AM
Just spotted this build and I must say nicely done! I haven't done a boiler yet but am hoping to attempt one in the future. That is a nice little feed pump! Thanks for posting a build on it!
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on November 28, 2013, 08:07:33 PM
Thanks Don, I was trying to work out how to include the URL in a post but the server didn't like the punctuation in the message and kept kicking me out.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: dsquire on November 28, 2013, 09:23:31 PM
Alan

Glad to help. Nice work that you are doing.  :D :D

Cheers  :beer:

Don
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on January 09, 2014, 03:00:15 AM
Finally got back to plumbing the pump into the boiler to attempt to get it running on real steam.  This is my first serious steam project so Im on a steep learning curve and may be missing some essential point so feel free to provide feedback and suggestions on what I have missed.
The power plant is a PM1 boiler coupled with a PM #8 steam engine. I set up a temporary oil trap, jam jar and plastic piping, for the test.


The initial test resulted in large amount of steam exhausting from the pump but no pumping action because the pump piston suffered from hydraulic lock. The amount of condensate from the engine and pump was large and rapidly filled the separator.  The volume of condensate led me to believe that while the boiler raised steam quickly the steam itself was highly saturated.  I modified the steam line routing it directly back into the boiler head space, down into the firebox via one of the fire tubes and up and out through a second fire tube to provide a degree of super heating. This did drastically reduce the amount of condensate in the separator to that generated by the steam condensing when it hit the cold masses of the engine and pump. It did not however, eliminate the lack of pump action.
 I disconnected and plugged the steam feed to the pump and fed the pump with a regulated supply of air.  I then fired up the boiler to run the engine.  Running the pump on air I adjusted the pump stroke and speed to replace the steam consumed by the engine and ran the system for an hour. Boiler pressure was between 10 and 25 PSI during the test.
To determine the PSI at which the pump was operating compared to the boiler pressure I replaced the displacement oiler with a pressure gage. To maintain the required feed rate I used an indicated pressure of 15 PSI which gave an open valve flow at 10 PSI. You can see this on the posted you tube video.
So I have a conundrum to solve; the individual components, engine and pump, run from independent pressure sources but not from the boiler alone. The pump requires less pressure than the boiler is generating so my current thought is that there needs to be some pressure regulation of the steam feed to the pump.
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on January 20, 2014, 06:36:28 PM
Finally have the pump and motor running but as usual there is more work to do. Having determined that the pump needed more of the available steam at a flow of at least 10 PSI while the engine will happily turn over with as little as 2 PSI of flow I designed and built a regulator to reduce the pressure and flow to the engine only discover that the ceramic burner I'm using only provides sufficient output to provide a flow that barely exceeds the minimum required. It is possible to get the motor and pump running at the same time for short periods but the pump was not able to replenish the boiler losses even with the burner on full and the fuel tank icing up because of the high evaporation rate. I  resorted to directing the flame from my trusty MAPP blow torch into the firebox which increased the flow rate to around 25 psi. The added pressure and flow ran both the engine and pump and the pump sustained the boiler level.  More heat or a more efficient boiler appears to be the solution. The test is on YouTube. If anyone has suggestion for a higher output heating source let me know.     

&feature=youtu.be
Title: Re: Southworth Engines Boiler Feed Pump
Post by: alanfrost on January 20, 2014, 07:47:06 PM
Eureka!!! I've been running my ceramic burner on butane lighter fuel as it's all I can get locally but I finally stopped at a camping store and picked up some butane/propane camp stove fuel and wow it really burns much hotter than butane alone so I now have the pressure I need.   
Title: Re: Southworth Engines Boiler Feed Pump
Post by: Steam Geek on June 27, 2014, 05:00:57 AM
I have actually got round to machining my set of castings, one thing that always bugs me on model engineering drawings is the lack of tolerance information.

What tolerances have you been machining to for your steam pumps? :nrocks: