Southworth Engines Boiler Feed Pump

[sbwhart]

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.



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.



Then mark out and center pop the bore position.



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



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



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



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



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.



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.



Stew

[saw]

I am very glad that you have taking this projet, I have thinking about this boilerpump.
Nice work. 

[lordedmond]

Stew


nice work

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

[sbwhart]

Cheers Chaps

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

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.



Drill the ports and the clamping holes for the steam chest



Tap the steam chest holes nice and square



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.



This machines cylinder



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



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.



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



This is what it looks like completed.



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.



These are the bits completed so far



And lose assembly



Stew
 

[Bogstandard]

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

[saw]

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. 

[sbwhart]

Thanks John

Saw I'll post bigger pics next time.

Stew

[saw]

Thanks Steve, no hard feeling but I learn so much from you so I will not miss it. 

[sbwhart]

Thanks Steve, no hard feeling but I learn so much from you so I will not miss it. 

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

 

Stew

[madjackghengis]

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,  Jack

[sbwhart]

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



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.



Grind up a grooving tool the width of the ring.



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.



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



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.



Fit the O ring



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



First turn the chucking piece up to get a clean diameter



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



Back face to thickness



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



and mill it out



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.



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.



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



And assembled



Stew

[saw]

Just wunderfull, tanks for bigger picture. 

[Stilldrillin]

Stew.
I love the way you work, and the work you produce. 

Watching/ enjoying, quietly...... 

David D

[madjackghengis]

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 , at some point I will have to invest.  Very nice pictures and explanations, fine craftsmanship all the way.   Cheers, Jack

[sbwhart]

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.



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.



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.





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



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.



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



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



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



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



Pick up the centre of the mandrel using a wobbler.



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



And mark it out using the indexer and height gauge.

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





Tap




Finished Job



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

And this is the assembly so far



Stew

[Bogstandard]

Looking absolutely great Stew.


John

[Brass_Machine]

Wow Stew... That looks very nice! 

[sbwhart]

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.



And in the assembly



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

Stew

[saw]

Looking very good 

[Divided he ad]

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"    So simple but so very useful to remember 




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







Ralph.

[Stilldrillin]

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! 

David D

[sbwhart]

Thanks very much Guys your support is much appreciated   

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

 

Stew

[Stilldrillin]

Thanks for the link Stew!

I've just ordered the Robinson displacer shaft. 

David D

[sbwhart]

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.



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



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)



Stew

 

[saw]

I'll think I must build this steam pump sone... 
You are building this pump very nice and it's so very easy to folow you, thank you.