SHED MATTERS 2

[Stanley]

Looking at progress this morning.... I shall tap the holes under the mill on the same setting to make sure they are vertical. Then I'll skim the lids to the final finish. I'll only fit two set screws because when the cylinder is mounted on the target plate on the bed they'll have to be longer. The back lid can have it's full complement.

[Stanley]

Carrying on from yesterday I put the 2BA tap down the holes using the quill and a pointer to make sure I didn't wander. (Memo to Stanley... must make myself a spring loaded tap follower...)



I blew the holes out and finished them freehand with the bottoming tap.



Set up for the other end. I lost my stop location so I'm setting it again for these threads. I also marked the lid and the casting to register the holes. Then exactly the same procedure as the other end but with one slight difference. I sacrificed exact template position of the two holes on the lid side so as to avoid the bore on the drain cock completely.



Same trick with the dowels. You don't need to clamp the lid down for drilling, the register and the pegs hold everything in place.



Change of setup and a 4.9mm drill do give me the clearance holes in both lids.



Knocking off time. Tomorrow the first thing I'll do is put a finish skim on the lids. Nice morning, no mistakes and we have progress. Quietly away, no rush....

[Stanley]

Now we have the lids ready for mounting it's time to skim them up to get rid of register marks and the chucking and holding bruises. The straight skim across the face was easy but the Harrison chuck was too big to get to the periphery easily so I went on to Johnny's lathe.



Nice finish, now for the same on the edges....



I love this lathe.... I had to demount the overhead gear and get back to normal running but that needed to be done anyway. Once I had the lids done I mounted them on the cylinder using temporary studs.





Close of play. We are ready for valve making now.....

[Stanley]

Today is all about making the slide valve.... First job was a chip chase round the VM and replacing the normal machine vise, properly squared up.



Next job was taking the lid off the steam chest so I could get in there. I popped the 3'16" drill through the gland just to make sure there were no burrs in it. Then some careful thought and measuring up. The most crucial measurement at this point was to get the centre height of the valve spindle above the valve face. I shall not be making the traditional valve but follo0wing the design that Newton always used which I think has a lot going for it. In this design the valve itself floats free and is not restrained in any way by the valve rod.



Then we went into the drawing office....



I found an off cut of bronze in the treasure chest big enough to get the valve blank out of it. This involved sawing it in two and while I could have done it by hand I wanted to see if I had been right in that even though the shaper is mounted on the HM table I could still do useful work. So I installed the other machine vise, squared it up and put a slitting saw in. It's going to work with a bit of care....



Half an hour later I had my rough block. No measuring at this point, I just want to get a squared up piece of stock. Once I have that I can do accurate measurements.



The usual process of getting one square face and starting from there taking the minimum off the stock.



Once I had four square faces I found an accurate square on the end so I could be sure I had it square in the vise mounted upright.



Knocking off time. I have a square lump of bronze and can do some accurate measurements for the final cut. Quietly away, no mistakes and not a bad morning's work. I am happy with that.

[Stanley]

This block of bronze has to go in that hole.



The first dimension is to get the width.



It fits in the hole now. Next job is to get the length.



A careful mark up, set it square in the vise and chew some more off. My El Cheapo mill won't take the heroic cuts we see on Youtube so we go quietly away at it.



Before I started the next cut, five minutes in the T&C grinder is never wasted. One of my better investments. If you see one don't walk past it!



Length, width and depth are all done now.



Now we need a 3/16" channel down the centre and cut to the correct depth so a bit of careful measuring first.



Speed the mill up, 3/16" cutter and a bit of patience....



You can see in this picture where the valve rod will sit but just for the moment it's a 3/16" drill.



While I have the small cutter set up in the mill this is a good time to cut the big port in the bottom of the valve. Careful measuring first.



At knocking off time I was set up for cutting the port 1/8" deep but that's for tomorrow.
Now it's confession time. After I had cut the slot for the valve and marked the port I put the valve back in the vise without thinking and tightened up with the slot still longitudinal. It felt soft and I realised what I had done, squeezed the two sides of the valve in and partially closed the slot. Not good! I carefully opened the slot up with a wedge (a cold chisel actually and a hammer) but didn't try to get it completely open because of the danger of cracking the valve. The cutter was still set for the last cut on the slot so I ran it through again and got my size. This means the sides of the valve aren't quite plumb but that's no problem and any disturbance of the flat base is slight and will be sorted out when I've cut the port and finish ground the base. Silly thing to do but I was lucky and got away with it.
One other thing, you'll notice that I haven't quoted any measurements for the valve, this is deliberate, go and find your own, plenty of drawings of valves on the web or in your library of books on steam engines!

[Stanley]

I forgot to mention this yesterday. Anyone who hasn't built a cylinder may wonder if there is enough room for the steam to get in and get to each end of the chest. Don't worry, there is plenty as it is but there will be even more when I cut the cross slot for the driving bar for the valve. One thing I found was that even the professionals made mistakes when leaving room for flow through a valve especially in the clack box of pumps. They set them up with up to 1/4" lift on a three inch clack which was far too much. 1/32" on the periphery of a 3" valve was plenty and much more efficient because in that case the valve closed quicker when back pressure came on it at the end of the stroke. It could double the delivery! Newton taught me this and he was right....

[Stanley]

I left this part of the job marked up and ready to cut last night. Not a big job as I am only taking just over 1/32" out. It won't look enough but believe me it's plenty!



I need a driving block for the valve so I got a box of offcuts out and picked one that looked handy.

First job was to make sure it's square.



Once it was square I could start looking for the size I want.



We have the size and it's square so now I am ready to mark the valve itself up for the cut that will be needed to accept the driver.



It's a shade under 3/4" so I had to find a cutter. I found this old broken end mill that had been converted to a two flute slot drill. I gave it a good sharpening on the T&C grinder and started shifting metal. Light cuts, my little mill won't handle heavy cuts accurately.



Quietly away until I had reached my depth. I need to be below the level of the slot for the valve rod as I have to drill and tap this block to accept the rod.



I couldn't finish sizing the slot with the old mill because it wasn't cutting cleanly on a side cut so I put another cutter in to finish it off. Here we have the driver sat in the valve. Ready for a bit of finishing and drilling and tapping the block for the valve rod... That's for tomorrow. I told you there would be plenty of room for the steam to get into the chest and round the valve!

[Stanley]

Finishing the valve. First thing was to get the warding files out and clean up all the internal surfaces and remove the burrs from the milling process until everything fits together nicely.



Just like this!



Stick a sheet of carborundum paper down on to the surface plate and polish all the faces. Take any burrs out that remain with small files....



When you're sure everything is working freely and fitting well, block the valve to get it solid and pop a 3/16" transfer punch though the gland and pop the location for the valve rod on the valve driver block. Before you take it out of the chest put two pop marks on the valve and the driver as a register and from now on always match them up.



I forgot to mention that I had a good chip chase earlier and harvested John's non ferocious scrap... Before putting the bigger cutter in the mill I gave it the lightest of touch ups on the grinder.



Before I put the cutter back in I used the VM to hold the driver block dead square and drill it 4mm, the tapping size for 2BA which is the thread I am going to use for the valve rod.



I tapped the hole on the same setting as the drill, again, to make sure it was dead square.



Then I found a piece of 3/16" bright stock and threaded it at one end for the driver block and at the other end for the clevis that will go on the end.



Almost knocking off time so I had a trial fit. Everything fits nicely and the valve runs true.



Then a bit of clevis designing, a fag packet drawing and find a piece of stock I can get 3/4" out of... ready for tomorrow. Nice morning and I'm happy with the way it's gone together.....

[Stanley]

We need a clevis.... It never fails to surprise me how big the stock has to be to make a small irregular shape!



Once I had the diameter turned and had drilled and tapped it for 2BA I put it under the VM to put the squares on it. I lined them up by eye, one of these days I'll take a leaf out of John's book and make a square and a hexagonal collet holder....



Once I had the square I popped a 1/4" slot drill in the mill and carefully cut out the centre section of the clevis.



Once I had the slot cut and before I sawed it off I cleaned it up with a smooth file.



The last job was to pop it under the VM and drill the 1/4" hole through it for the pin.



We have a clevis on the valve rod. First job tomorrow is to make a pin for it.... Looks even more like a cylinder!

[Stanley]

Not sure at the moment but writing articles may trump the shed.... If so, apologies lads.

[Stanley]

We need a clevis pin so a bit of measuring, a fag packet drawing and find a piece of stock.



Off we go!



I checked to make sure I had a good fit...



Another little step forward.



Once again I have to start getting stuff out and littering the bench.



I made the retaining collar and drill both it and the pin at the same time. Size the hole to take the middle diameter of the taper pin, you can cut the excess off when it's finally fitted.



Just about right.



The cylinder is nearing completion. No more machining on it so we can do some finishing touches. First one is to get a seal between the steam chest and the valve surface. If you want to fiddle about with paper gaskets, go ahead. I'll stick to liquid sealer, I've never had one leak yet. Mind you, this depends on how well you finished the faces.... First thing you have to do is separate the surfaces of the joint. These are so tight I have to start with a packing knife and then go on to different screwdrivers.



No need to take the chest right off, you just need enough room to get the joint compound in. I'm using Loctite liquid gasket. Once you have it in, gently tap the lid down with a hammer and wooden drift and then pop the lid on and tighten the nuts up evenly until gasket flows out of the joint then wipe the excess off and take the lid off again.



Clean the excess from the inside as well. A cotton bud is handy here.... And yes, I did get the bit I'd missed!



The next job is packing the valve rod gland but it was almost knocking off time so I'll leave that until tomorrow, however I got the packing string out of it's hidy hole under the 1957 lathe. One of the disadvantages about having a well populated shed is that you have to shift a pile of stuff to get to some items! Then I had a quick chip chase.....

[Stanley]

Late yesterday afternoon I improved the shining hour by going back and looking at Shed Matters 1. Interesting to go back to the puffer engine and marvel again at the wonderful job Mick did on that Harrison lathe......

[Stanley]

Later... Sorry lads but I have to address the BET article pile.....

[Stanley]

I was in the shed before 07:00 this morning. First job was to pack the gland on the valve rod. Get as much in as you can, then compress it with the g;land nut and put some more in until you have a solid packing and sufficient threads inside the gland. Oil the rod afterwards and rub it backwards and forwards, than give it a final nip.



The front cover won't have to come off it again so you can put some liquid gasket on and nut it down tight with the two temporary studs. You can't do anything about the permanent studs until you are fitting it to the target end on the bed.



We're ready for packing the piston. Get your tackle together. The jubilee clip is going to be your best friend....



Get as much packing as possible into the groove on the piston and compress it with the jubilee clip. Put plenty in and finish up with the clip dead tight but slightly proud of the cylinder diameter.



Assuming you have the piston turned to the right diameter it will enter the bore easily, oil the bore before you do this. The piston rod will slide easily through the gland because you haven't packed it yet. Once it is entered, knock it in with a solid wooden drift and quite a heavy hammer. You can't do any damage it's only excess packing that's holding you back.



As the packing is forced into the cylinder the sharp edge of the bore will cut any excess of like a shear punch. Don't worry if the piston then feels a bit loose in the bore, this is normal because it is perfectly sized. It will be steam tight, don't worry!



Once the piston is home you can cut the remaining set screws to the right length to take the full depth of thread you cut. Don't put any packing on this lid yet because it is probably going to have to come off at some point when you are doing your final fitting when you are erecting the engine.



Once you have the gland packed you can temporarily put the valve chest lid back on and nip it down to keep the muck out. Don't put any packing in as it has to come off again when you are valve setting. You can leave the studs as they are, no need to file them down to finished length yet and you know all the nuts are free on their threads.
I'm in trouble now! To all intents and purposes, apart from drain cocks, this is a finished cylinder. Now I have to decide where to go next! I'd been at it for two hours so I decided to be kind to myself, do some putting away and tidying up and retire for a think.....



Just for reference, this is my serious piston ring compressor which I used to use when building slightly bigger engines... It will go up to about 9" bore!



If you have a good surface plate, look after it. They have a nasty habit of going rusty if you don't! Everything cleared off, a good rub down and a good spray with WD40.



That'll do for this morning. A clean tablecloth on top of an oiled up surface plate and all the tackle cleaned off and put away if necessary. I do like a straight edge!

[chinatyke]

I thought of a next project suggestion for you whilst I was looking at you making the valves.

Do you remember the wooden cube puzzles made from various pieces that all slotted together to form the solid cube? Wouldn't one of those look nice in brass and imagine the lovely feel of perfectly finished lubricated brass slilding together. I guess you can still get the wooden ones to use as a pattern.

Just an idea to consider.

[micktoon]

Hi Stanley, just been checking in to see your progress and there has been plenty . Its looking really good and well documented and explained too. Like you say you will needing the next project soon, the brass puzzle cube coukd be interesting ?

Cheers Mick

[Stanley]

I'm not into puzzles China.... Thanks Mick... when say I am going to retire to think it's about what to do next to make it into an engine.... I need to get some cutting sizes out for 3/8" steel plate and have a word with my mate Terry..... Question is do I make an overhung crank or one like the last one.....

[Stanley]

I can't do anything about sourcing my materials for the engine bed until tomorrow but there are things I can carry on with....



For a start off I can put the 26tpi thread on the end of the piston rod because I know it's about the right length and there's latitude when I get round to positioning the cross head into which it will screw. So I took the back lid off, undid the nut holding it into the piston and after slackening the gland nut, drew it out carefully.



I squared the end of the rod, put a 45 degree chamfer on it and threaded it for just over 1/2" which will be plenty.



Tip. When you put the rod back in put the newly threaded end in first and screw it through the packing. If you try to put the other end through with the shoulder on it will almost certainly foul the packing. Once it is in, withdraw it carefully, oil it and pop it in the right way. I'm tightening the nut on the end of the rod here and restraining the rod using the die I have just threaded it with.



Plenty of oil in the bore and pop the back lid on again. The piston runs better now the nut is tightened properly on the piston, a very satisfying sucking noise when you move it back and forward and it runs easily and smoothly.



Another job I can do is make the drain cocks so a bit of designing, a fag packet drawing, check my threads (1/4"26tpi) and a furtle on the treasure chests.



You were no doubt wondering about the rusty p[iece of stock for the plugs of the cocks. It's a good example of the way you have to keep your wits about you. It looked rusty because when I found it it was outside mixed with some badly rusted steel stock. It is actually a piece of brass which will do nicely.



Why a picture of a brush? I was up early this morning to look after Jack and decided I didn't want to immediately plunge into making drain cocks. When I was in the shed in the back yard the other day I realised I had a long sweeping brush with a worn out head I'd forgotten about. I also had a new brush head in the treasures so the solution was obvious. Scrap the old head, clean the stale up and finish up with a good soft sweeping brush for nowt.
That'll do me for this morning, I'm ready for my dinner and a good sleep....

[Stanley]

The first job this morning was to do a bit of measuring, draw up a cutting list and send it to my friend Terry at Gissing and Lonsdale. The engine will be about the same size as the last donkey....



My mind has been working on the flywheel. I've run out of flywheel castings at £80 a throw by today's prices. I was considering asking Mrs McMaster to cut a slab off a piece of 6" stock I have about me but then remembered this chuck back casting. I doubt if I will ever need it and I can get an 8" flywheel out of it. The oversize hole in the centre doesn't matter, I can soon plug that up!



Then back to the matter of the drain cocks....



Basic stuff, I just cracked on at it. 1/8" bore and 1/4" 26tpi at each end.



At knocking off time I had the bodies partially finished, I shall turn the other end down and thread them tomorrow.

[Stanley]

It's nice to have friends.... I got mail from Terry last night that my cutting list was in the shop and he would mail me as soon as it was ready. As it's small and will be easily sheared on the guillotine I will soon have the materials. I taxed him about payment for it and the bed for my shaper and he said that we'd get round to that..... Nice!

[Stanley]

Carrying on with the drain cocks and before anyone starts criticising my lack of speed, it's quite amazing how many operations there are to making them! Today I am working on them to make a tapered hole for the cock, make the tapered cock to fit the hole and add a handle. There are more operations needed on it but this is today's target. The first job was to find a 5/16" tapered reamer and get the first body set up under the pillar drill. Notice the vest pocket level. This is something I learned the other day watching Adam Booth on Youtube. He used a small level like this to ensure a small item was set up level in the machine vise. I realised I had one in the front room but have never thought of using it in the shed. I got it out and it's perfect! Check the level of the jaws and then set the workpiece to the same bubble. Dead easy, works like a charm. You learn something new every day!



Once I'd centre drilled, poked an 1/8" pilot hole through and followed that with a 1/4" drill I put the reamer in the chuck, set the speed to slow and reamed the hole out, all at the same setting. I did the other body exactly the same. Now we need a matching cock.



I'm going to machine the taper on the cock by offsetting the top slide and using that, it has plenty of travel. There are all sorts of fancy ways to set the slide, you can spend hours looking tapers up in Machinery Handbook and still get it wrong. My way is to put the reamer in the chuck and set the slide by trial and error. The white paper on the bed helps you to see how you are doing.



It must be my lucky morning.... Got it dead right, a lovely feeling to the fit.



Then drill and tap the end for a 2BA set screw which eventually will restrain the washer that holds the plug in the cock.



Nice!



I set the bar with the cock on the end under the pillar drill using the level before I cut it off. Found the right taper reamer and taper pin, drilled the appropriate sized hole. Use a drill that is the same diameter as the thinnest part of the taper pin. Don't worry about the taper, when you eventually knock the pin in it will make its own fit. I didn't want to alter the setting of the tool and the top slide so I cut the cock off by hand and finished the end on the grinder. (I know.... but it was the easiest way!)
That's it, one cock almost finished. That took care of a couple of hours! But, in my defence, no mistakes and a good fit. The next one will be easier because the body is drilled and tapered and I have all the tackle picked out and to hand.



They say you can always tell a good fitter because his bench is uncluttered and tidy. I leave you to draw your own conclusions!

[Stanley]

Mail from Terry. My bed plates are cut and waiting for me. Nice to have reliable friends.....

[Marilyn]

Nice to see you are keeping busy, Stanley.

Where do you leave your pipe when you go to bed?
(It seems to be with you at all times)

[Stanley]

It never goes upstairs Maz, I only smoke downstairs....



I started the day by doing the same operations on the second drain valve as the first and then carried on with the finishing touches on both of them. First thing was to line the handle up with the bore and poke the 1/8" drill through the cock. It will be open when the handle is in line with the bore and closed when it is crossways. All drain cocks were made like this so that the engineer could see at a glance whether they were open or closed.



The two cocks finished apart from making arrangements for piping the condensate away. I've left plenty of meat so I can have a choice of how I do it, if and when.



Next I decided to make a start on the flywheel casting. I started using the big three jaw SC but soon decided this wasn't the way to go.



I popped the big 4 jaw on and set the casting up as near central as the shape would allow.



When I got as near as I could I started cutting to get a face on over one half of the rim. Biggest carbide round nose I have and 75rpm. This brought us to knocking off time but there was one more job to do....



I took Jack for a walk down the hill to Gissings and picked my bed plates up. Plenty to go at now!

[Stanley]

The design committee met last night and have recommended that I ditch making the flywheel for my latest engine out of the large casting. Instead I shall cut a slice off a large piece of 6" stock I have about me using the services of Mrs McMaster. 6" is too big to cut at one pass, it will foul the frame but I can cut it in two cuts. I'll continue to clean the big casting up now I have it set up in the four jaw but then put it back into stock. The committee is right, it's a waste of good material...