SHED MATTERS 2

[Stanley]

First job was to adjust the underside of the bed. I tried it on the surface plate and it wasn't quite seating properly. Probably a bit of warping after welding. I got a big flat file and dressed it flat. (One of my favourite engineering quotations is what one of Maudslay's men said of him after he died. He said it was a pleasure to watch him with a hand tool of any description but he was particularly fine with an 18" flat file'.)



Ten minutes work and it seats perfectly.



It's a pleasure to get back to some proper fitting after the last few days. I want to thread the end of the piston rod ready for fixing in the crosshead. Also on the agenda is a precise measurement of the travel I need to get on the slide valve. I need this before I make the eccentric and the chest has to be open to get it. I got a bit imaginative when I made this valve, I wanted to try a shorter valve and more travel so my usual 1/2" throw eccentric won't do. I also want to shorten the valve rod a bit, it's too long at the moment.







First job was to get the piston rod out, reduce it to 3/8" and thread it 26tpi. Finished off by giving it a good polish. Then I put it back into the piston, lifted the valve chest lid, measured the throw of the valve and reduced the valve rod by almost an inch.



Here it is ready for a trial fit on the target end and marking the crosshead. That'll do for today. The next two pics show that there's been a fitter about, tools all over the bench, drawers and boxes open, lovely! You can't have too much tackle!

[Stanley]

First job is to put a steam pipe in the side of the valve chest. So out with the valve and the rod and off with the rod guide because it is interfering with one of the studs if you remember!



The chest is very snug on its studs, any closer fitted and it would be impossible to get off! But, a bit of levering and it's off.







The usual sequence, mark out the position making sure you aren't interfering with stud holes, centre drill, 3/16"pilot hole, 8.4mm tapping drill for 3/8" 26tpi, start tap under the drill and transfer to the vice for finishing off.



Once the chest has been cleaned up and the oil taken off the valve face, I painted the mating surfaces with non-setting jointing compound. If you have a good finish no need for gaskets. Then clean out the valve seat face after getting the chest back into position. Then refit the valve and rod on a bed of oil so that if any excess compound gets to the valve it can't set but will be wiped off by the valve. Then nut the lid back on and clean off any compound that squeezes out of the joint.



I made the steam connection and fitted it no problem as I have plenty of 3/8" heavy wall copper tube. The 1/2" exhaust had to be made out of brass rod.





The cylinder is ready for offering up. The back lid is off because I need to get to the piston rod nut...



Fixing the cylinder in place. You can't beat having the right tools, those studs would be a bugger to get to with a spanner.



All the bolts in place and tightened up, very snug fit but no problems.



The good word is that the slide is exactly the right length, the rod is central on the crosshead dead in the centre of the meat. Further, at a rough guess, I am going to get away with the flyshaft centre without any extension of the bed. It looks as though my fag packet measurements were OK after all. Amazing!Tomorrow I can mark the crosshead and drill and tap for the piston rod after working out how much meat I can take off the block....

[PanBiker]

Looking good Stanley.

[Stanley]

Thanks Ian, it's surprising me as it grows! It's going to be a very compact and powerful engine! Nice thing is that the proportions are going to be OK as well. I popped in the shed last night, ground the face of the crosshead block and gave it two coats of blue while it was warm. It will mark nicely this morning.... I have a cunning plan to make the block shorter......
Later at 07:00. Back from an early walk, can't wait to get into the shed! Isn't it great to have an interest and a full day!

[PanBiker]

Indeed Stanley, we now have Ruby for the week. I have some more bits for moving my ground tuner on but doubt if I will be able to get into my shack to forward the project on. Lots planned with our Rubes though.

[Stanley]

Nice morning and everything has gone well. I got so engrossed I kept forgetting the pics! I started by marking the crosshead and drilling and tapping for the piston rod. Then I started cutting the excess meat off, I told you it would get smaller!



I only had metric silver steel so I had to reduce some a touch for the pin on which the con rod swivels. Soon had that done and nailed everything together...



Here's the result of the morning's playing out... I've got the con rod at the end of it's travel here and popped Newton's crankshaft in place. The good thing about this is that at the end of the stroke the crankshaft centre is inside the limits of the bed. This means that I can make a pedestal that only overhangs the bed slightly so no more welding! Everything is going to fit nicely and Newton's con rod and crankshaft will definitely do. The only thing that I found is that Newton didn't get his con rod fork exactly at right angles with the bearing end but I can adjust that when I make the bearing. One thing I have decided (but of course I might change my mind,,,,) is to make the flyshaft bearings solid. This was not uncommon on donkey engines as they could be easily replaced or bushed when they wore. A solid bearing lasts much longer than a split one....
A very satisfying morning. Now for a sleep before I go to Earby for my birthday tea!

[Stanley]

I've decided that the next job is to get the con rod straight and make the crank pin bearing. Once that is done I can do some measuring and decide on the centre line of the crankshaft.... So I've been in the treasure chest and found a lump of brass I can get the bearing out of.... A good start!
Later.... Not a great deal to report this morning, first job was to solve the mystery of the con rod being slightly skewed. After a bit of measuring I found that Newton's con rod was fine, it was the fit of the pin in the crosshead which was causing the trouble. Once I had identified it I put it right and moved on the the brass for the crank pin bearing....





It's surprising how big a lump you need for the brass. First I cut a slab off the right thickness, milled it perfectly square , marked it up and cut it on the other axis.



Getting there! I've left it slightly oversize at the sides and now I have to cut it off to the right length, we want to finish up with a square block, as long as it is wide.



At close of play I have a block ready for the next stages. If you are really eagle-eyed you'll note that I haven't quite cut to the mark. This is because one of the operations to come is to split the brass with a slitting saw, it has to be split to allow it to be fitted because of the design of the crankshaft. Doesn’t look a lot but I'm satisfied.

[micktoon]

Hi Stanley , it sound like Happy Birthday wishes are in order , I hope you had a nice birthday tea.
Good progress in the shed too, sounds like you are pleased with the results so far too
The 3 jaw is finally back on my Harrison , with great thanks to John , his latest video shows it getting sorted out, we are both more than pleased to see the back of that bloody thing I can tell you but its made some good videos for John too.
Keep up the good work Stanley .
Cheers Mick.

[Stanley]

Glad you have the 3 jaw running. I have been watching John.... Haven't seen the last video though. Now we need to see you turning a test bar.....
Yes, I'm pleased with progress and the way it's shaping up, particularly the way the proportions are working out. I'll make the pedestal for the main bearing heavy enough to balance the cylinder end up. It's going to look good when it's finished. We are nearer a finish than anyone thinks and this is the time when you have to guard against rushing... I have plenty of time....

[chinatyke]

I've been following your progress with much interest, it's wonderful to see it taking shape. Will you be fitting a fly wheel (is that the correct term?) on to it?

[Stanley]

Thanks for that China, I'm glad you are enjoying it. Yes, and a belt pulley as well. Haven't made my mind up about the size of the flywheel yet, I have a couple of options..... Main consideration will be to have it to scale with the rest of the engine. Proportions are important for the final result.

[Stanley]

This morning's task was quite simple. Fit the co rod with two studs that will hold the bearing brass in place. Nowt to it if you can see and can trust your eyes! I can't, so everything got more difficult. Including distinguishing between 0BA and 1BA studs!! But, if I've learned anything at all recently it is that you can cancel out these problems to a large extent by using supportive methods and triple checking everything! Even so I get to the stage where, even though my eyes are telling me something is wrong, I have to ignore it and trust to the method.



I won't bore you with how long it took to get to this relatively simple stage. I had decided to tap the holes through the foot of the con rod and fit a backing nut as this meant I could have the studs rigid for transferring the measurement to the bearing block. Incidentally these holes are always awkward because you have to drill them from the back as the chuck is blocked by the shaft of the con rod. Going on previous experience I have made the brass slightly over size as it can be trimmed back in a later operation.



I think it took over an hour to get to this point but the studs are firm and look as though they are pointing the right way!



Another hour later.... Things could be worse! I had to give the holes through the brass another .2mm extra clearance, not because I was out of line but because I'd underestimated how much I needed. The suds are snug in the brass and it took a little tap with the hammer to get a seat.



Close of play and not a bad result. Just a slight misalignment but I was expecting that and have allowed for it. The next stage is to mill the brass while it is fitted together like this so the fit will be perfect because I'll mill back to the shape of the foot. I left enough meat in to allow for this.
One thing did surprise me, I measured the crank pin before starting because I knew I couldn't have the studs interfering with the bore for the pin and it was about .75" I had assumed it was .5". No problem, I've allowed for it. All told, two and a half hours of patient careful work but no sweat, there is plenty of time!

[Stanley]

I'd been puzzling about the next stage. I wanted to mill the surfaces of the bearing flat and square and in line with the foot of the con rod. It dawned on me last night that I might be able to use the edge of the machine vice as a register and hold it solely by the flat surface of the con rod foot. So I popped into the shed and tried it, it looks OK.



I checked that all the nuts were tight and made sure the face of the bearing brass was tight against the square end of the vice jaw. A but precarious but it should work. Fine cuts putting as little pressure on the brass as possible.



After I had done both sides I addressed the faces. Not as easy because I couldn't use the jaws as a register. So plenty of fiddling with parallels until I had it as close as possible. Normally I'd have trusted my eye but......



Not bad. There's a bit of a low point on this face but that';s nothing to worry about. I took all of these surfaces back until I was just skimming the foot of the con rod.



Most important! At this stage put a witness mark on the foot and the brass. It's so easy to get orientations confused! If you look carefully there is a zero on the foot and the face.



Next job was to mark the centre of the brass for splitting. Once more a witness on either side of the cut.



I'd left plenty of meat in the brass so no problem in using the slitting saw on the HM.



Back onto the foot for a fitting check and the centre line of the split marked and a centre hole drilled under the pillar drill. This is for use as a register when setting the brass up in the lathe for boring to .721" I took the brass off the con rod and nutted the two halves tightly together.



Set up on the lathe in the two jaw chuck and ready for boring. This was close of play, a nice easy start for tomorrow morning.

[Stanley]

My first job was already set out for me. Bore the crankpin bearing out to a shade over.721" Freshly sharpened boring tool, meat taken out to half an inch with drills and away we go.



The last cut, a spring cut coming back out of the bore.



Bevel the edges, make a last check and we have a bearing. I can't tell you how many times I measured it! Every tool was used. I must have done something right because I finished up with .722" Bang on the money.



I put fresh witness marks on to replace the ones I had bored out and bevelled the inside edges slightly so that they didn't act as wipers taking the oil off.



Then a trial fitting, everything OK. There are some finishing touches to be added later but this is fine for the moment.



I put marks on the slide for each end of the stroke and dead centre and fitted the con rod to the crosshead slide so I could get some ideas about the location of the crankshaft centre.



Some serious measuring and a hunt for some stock for the bed under the flyshaft bearings.



Once I had the measurements I cut two 4" lengths.



Close of play. The bed for the bearings will overhang the main bed by about an inch to make it look right. I was going to do this by shaping the underside but then decided there was an easier way. I'm going to have to make a wooden base for the engine to give me clearance for the flywheel. I can step the wooden block to fit the junction with the main bed. When it's painted black to resemble cast iron they'll never see it off the Ribble....

[Stanley]

The design committee in my head has been working on the overhang all night. When I got up this morning it presented and alternative to the management and they liked it so we will go about it in a slightly different way..... They do good work while I am asleep!

[Stanley]

The design change the committee had decided on was to use the piece I cut off the target end as an extension of the bed to enable the pillar blocks to be positioned nicely and supported. No need for any welding because it would be integral with the pillar blocks which are going to be bolted down on the bed and when the base is put under it the extension will be bolted down to that as well. So the first job was to square the extension up and make sure it was exactly the right thickness.







Once that was done I squared the ends up on the pillar blocks.



This gives you the idea of where we're heading.



The next job was to adjust the size of the pillar blocks to give a comfortable clearance for the crankshaft and also face the bases so they sit firmply on the bed. I intend to leave the outside faces as they were in the black bar as they will look like a casting.





Close of play. There is more to be done on the blocks but we have good faces and a comfortable gap in the middle. One thing about this view. You'll notice that one side of the crankshaft is a bigger diameter than the other. At the moment, in this view it is on the valve chest side but I will be fitting it the other way round so that the larger diameter will be supporting the flywheel. It makes no difference for this trial fit.
Not exciting but solid progress....

[micktoon]

Hi Stanley more good progress , its late so I am off to bed , just wanted to say I have the die from John's so its all my fault if you don't get it now but I will send it off asap. Hope you have good weekend.
Cheers Mick.

[Stanley]

Don't worry about it! If you see John tell him I am trying to mail him but have had the mail returned. I have sent it again....

[Stanley]

The design committee presented their latest thoughts this morning so I knew exactly what I was doing. The job was to complete the finish on the rising blocks for the flywheel bearings and fix them to the bed so that accurate measurements could be made for the centres of the flyshaft bearings. In addition, they wanted a bit of titivation....





You can do things easily on a horizontal milling machine that would be difficult on the VM. There was another advantage. The small diameter cutters meant I could run the mill in high range. Not often that I get up there so it was good for the gearbox, it polished gears that hadn't been used for a while!



Here's the result. I had only polished one of the top surfaces when I did this pic. I went on to polish the other and break all the edges. They were both finish milled on the same setting so they are dead level with each other. The job now was to get them located on the bed.



Setting the engine up was more difficult that it might seem because it is unbalanced at the moment and won't sit flat of its own accord. I cut a plywood pad for it to sit on, got it in roughly the right place and held it down with the quill while I got the blocks in place and clamped them. I got them both clamped and set them by feel to where I thought they should be and then I checked the alignment with the dial indicator callipers. I got them within 2thou of truth and clamped them down tight. Then I marked the holes for the first holding down bolts, centre drill and a 3/16" right through to the plywood pad.



Knocking off time and this is what all the fiddling was for. Two holes right through the base. Tomorrow I shall drill and tap the holes and fix a 1/4" whit stud in each hole so that the blocks can be bolted down tight with one location set. Then I can set up for drilling the same holes on the outrigger section. These will only be temporary fixings as when I finally mount the engine on its wooden bed these bolts will go right through just like proper holding down bolts.
Slow progress again but everything checked and checked again, I think I have it right!

[plaques]

and fix a 1/4" whit stud in each hole

Never heard of anyone using 1/4 whit since the railways closed down. Whitworth was used in cast iron for some applications but generally speaking for steel it was all BSF.

[Stanley]

When did you ever see a BSW thread in steel fail? The most common US thread is the National Coarse, exactly the same as BSW. I'll stick to my 'old fashioned' standards thank you.

[plaques]

Don't talk about american threads, they are still using threads that went out with the ark. How many times have I seen a 1/4 whit fail? Too many to know that some ham fisted mechanic will screw its neck off.

[Stanley]

I've got better things to do than defend BSW P so you have your own way. I'll follow the old engineers, after all, it's an old engine I'm building....



Start of play. Looks as though there is a fitter about! Today's job is to complete the fixing of the rising blocks accurately on the bed and the extension using 1/4" British Standard Whitworth bolts! Nowt to it......



A good start, usual drill, centre drill, bore both the rising block and the bed tapping size, tap the hole in the bed and then drill the block clearance for the bolt, 1/64th over a 1/4"



Once the first bolt was in I had to make sure that the other was in exactly the right place. I used a packing piece and an adjustable parallel to make certain I had the block correctly positioned. Overkill I know but I can't trust my eyes, this way I could be reasonably certain I had everything right. Takes more time but no cock-ups!



I got the matching bolt in on the opposite side and then attacked the one on the other side after making sure everything was correct using the parallels again. There's a shortage of pictures here because the gremlins struck! When I drilled the tapping size in the third hole the drill broke off in the hole part way through! Before anyone asks, I haven't the faintest idea why. The only thing I can think is that there was an inclusion in the steel and I was unlucky enough to hit it. I got it out by measuring up very carefully and drilled the block from the opposite side until I just broke through and then punched the broken drill end out with a succession of very slender punches. This was not done quickly!
Once I'd retrieved that situation without cocking the hole up I went on as before but as you can guess, very carefully!



Close of play. Both blocks firmly bolted down in the right place. I checked them for parallel and there might be two thou difference between the ends. Not bad for a half blind fitter! I'll settle for that.
Contrary to what I said before I'm going to run a weld across the bottom side, I think I can make a good enough job. Before I do that I want to drill the cylinder wall for a lubricator. I've decided to fit one and the engine will never be set up better than this to do the job. The lid is still off the far end so I can make sure I get all the swarf out... I shall drill and tap it for 3/8" brass thread, 26tpi, another archaic but totally authentic thread! There will be four of these lubricators, Cylinder, crank bearing and one on each flywheel bearing.

[chinatyke]

Can I ask a naive question that has been puzzling me?

Why do you use brass and phosphor bronze bearings and not roller or ball bearings?

[plaques]

Why do you use brass and phosphor bronze bearings and not roller or ball bearings?

Or for that matter a tin based Babbitt metal. Formulated way back in 1839. in USA (wash your mouth out) Now commonly referred to as 'white metal'. But as you say "its not running 300 looms".