SHED MATTERS 2

[Stanley]

It all started so well.... A sharp carbide tool with no rake and nicely rounded in the tip, some very careful measuring and away we go.



Two 50 thou cuts and it was a perfect fit so an extra one thou cut to give us a bit of clearance and we had a fit in the bore. Next job the piston ring grooves, 2X 3/16". No problem....



You can be forgiven for wondering what I'm doing pissing about with the VM. Would you believe that amongst all the parting tool steel I have all the 3/16" stock is specially shaped to fit a holder which I don't possess! I had hit this problem a long time ago and made myself a couple holders for the steel. Problem is that it was made for the toolpost on a bigger lathe, the old Wilson, and the holder won't fit my quick change post. It would just fit in the Harrison toolpost but the cutting height was too low. Of course I could have ground a piece of ordinary tool steel to shape but being a stubborn old bugger with plenty of time I decided to modify the holder so I can get it in one of the quick change blocks. That's why I'm milling steel!



It fits now and here I am doing a lot of swearing, waving a large magnifying glass about but eventually getting it set correctly.



Close of play. The tool set square and ready for some more measuring and groove cutting.... Never mind, I won't hit that problem again. Come to think there are two of those holders, I think I'll cut the other one down as well.....

[Stanley]

I told you the other holder was nagging me. It fits the quick change toolpost now.... I do like straight edges!



Back to the main event.... All set up and the new parting tool cut beautifully. Don't forget that when you're parting brass yo need a sharp tool, ste with no rake or a touch of negative and if anything mounted a tad below the centre line. That way you won't get any grabbing and digging in. Brass is a bugger for that. By the way, the same applies to drills as well, stone the rake of the cutting edges or you'll tend to get the same grabbing. The old turners used to keep a set of drills separate for brass.



Next job, pop a centre hole in and drill right through with a quarter inch drill. Keep pulling back and clearing the chips because another unfortunate habit drills have is choking on the chips and grabbing! I followed this with the 3'8" drill I wanted.



Next job is the counterbore for the nut with enough room for the socket. I just happened to have an old end mill that is 0.9", a bit blunt so just right, no grabbing!



I knew I was OK but just for a laugh I tried the socket in the hole.... Better now than later after the set up has been disturbed. That was it, I called it close of play. The great thing is that there is no pressure on me, slowly and carefully cancels out the eyesight!

[Stanley]

This wasn't the start of the day in the shed, we had another matter to address first. I got the shed Hoover out of the cabin in the back yard and the beater was jammed. So, a quick strip down, clean the bearings and oil them and put it back together again. That cured it! I broke the edges on the counterbore and the rim of the piston and then had to re-chuck it to part it off. Here we are being sensible again and dialling it in.



Parting should have gone well but no such luck. For some reason it started cutting badly and generating heat. I wasn't in the mood for investigating and making changes. I was half way in so I took it out of the chuck, cooled it down and cut it the old fashioned way with a hacksaw. All right I'm a wimp but I wasn't taking any chances.



I decided to break new ground for me and use a tipped tool I had ground to modify it. I wanted to clean up the slug that was left over so I tried it out on that. No problem, a good cut and finish.



I popped the piston in cushioned with some card so the jaws didn't mark it. Last job was to break the edge and eun the 3'8" drill through to clean the bore.



We have a piston and a clean slug of brass.... Next job is to make the valve rod guide that goes on the top of the steam chest.



A little tip here. If you want to check whether your tool is on centre height, pop a thin steel rule in between the tool and the work and nip it with the tool. If you are dead on centre it will be vertical....



I'd sorted my dimensions out and started cutting. It always amazes me how much material a small component takes if you are chopping it out of the sold....You can't see it here but I have made a mistake. I'd forgotten the centre drill hole in the end of the bar which I would have to turn off because this has to be blind and steam proof.



Close of play. I've got rid of the centre drill hole and started again on the body. Tomorrow is another day!

[Stanley]

It all started so well.... First job was to get rid of the centre hole, re-measure and get the body of the guide chopped out.



The end has to be domed so I popped a form tool in, got the shape and polished it up.



Mark the junction of the sizes with the parting tool and cut it off. Then I reversed it in the chuck protecting the finish with a layer of paper.



Next job was to get all the right tackle out and fit a 1/2" X 26TPI die in place and away we go. This was where it all went wrong. I forgot two things, first that these dies are very sharp and second that they need to be opened up as big as possible in the die holder because they tend to cut too small otherwise.



I thought it felt a bit tight but crashed on! This was the result, a buggered useless thread far too small for the hole. The air was blue....
So, what to do, make another one? I decided against that I shall punish myself by reclaiming this. I shall retire hurt and return like a giant refreshed tomorrow. These things happen and we all have cock-ups. I never hide them from my mates, after all we might learn from the experience.....

[Stanley]

Can't wait to get back in the shed to rectify my stupid error... Am giving myself a hard time!

10:55. Had a good morning but it didn't start well!



The task was to make a brass plug threaded 1/2" X 26TPI. Bore the guide out tapping size for the same thread and screw it in, then bore 1/4" for the valve rod. Nowt to it. I cut a slug of brass, put a chamfer on the end and went to thread it using the die holder for accuracy. I'd made sure the die was opened up slightly in the holder so it wasn't cutting too keen. Result? Exactly the same as yesterday! A totally buggered thread. I checked everything again but found no errors. Bit of a my7stery.... All I could think was that the answer was in my eyesight so I started again but checking everything twice. As a final test I rotated the chuck with the die holder on the bad thread but without its tail being in the guide. That was it! It wandered all over the place. The problem was that the die holder doesn’t automatically locate central on the holder, all I had to do was slacken the fastenings, mount it on the guide while still on the thread and rotate the chuck. Tighten up the fastenings and Bob's your uncle! Problem solved. I'm sure that if my eyes had been better I would have noticed the misalignment. Onward and upward....



I soon had the plug made and chamfered and popped the guide back in the chuck to turn the buggered thread of it.



Centre drill it....



11.5mm tapping drill poked up it



Then put my heaviest tailstock chuck on and thread it 1/2" X 26 to full depth.



While it was in the chuck I drilled it 1/4" for the guide hole for the valve rod and then screwed it into the end of the valve chest. I had to run the die down it again with it nipped up a touch because I'd left it wide open in the die holder.



Last job was to drill a 3/16" hole in it for a tommy bar to tighten it up. The problem had been that my tailstock die holder was so good it was rigid and the wander in the die holder was held firmly enough for the die to cut eccentric....



Here's what we were after all the time but it took a while to get there!



That out of the way I addressed the gland nut for the other end of the valve chest. I started with my reclaimed brass riser.



Close of play. A bit of drawing so I knew where I was going and the major and minor diameters turned on the slug with a chamfer on the end ready for some trouble free threading tomorrow!
I feel better now I've cracked that one. Bugger the eyesight!

[Stanley]

Everything left ready so it didn't take too long to turn the major and minor diameters. Then, the dreaded threading!



Absolutely no problems. Just as it ought to have been for the guide!



Before I parted the gland off the slug I popped it under the mill and bored four small tommy bar holes in the rim. This one needs more than one because it is harder to get to because of its position.



I sharpened the parting tool, what I should have done yesterday and no problems at all.



After facing the parted end off, here it is ready for the rod and valve.



After a bit of measuring up and deciding sizes I started on the bottom cylinder gland. Plenty of meat to go at and here's the major diameter coming in to size with one cut after a starting cut to get a good measuring surface. This was close of play, hopefully tomorrow will go as well as today!

[micktoon]

Hi Stanley , Christmas activities have had me distracted but good time had by all. It looks like you have had good and bad times in the shed but are winning overall so I hope tomorrow is another good day for you. I hope it will be warm enough in the shed too as its got a lot colder the last 24 hours, its a heavy white frost out there tonight, looks like winter has finally caught up with us !
You will have to be thinking of your next project soon at this rate Stanley.
Cheers Mick.

[Stanley]

Do you know Mick, I was pondering that very thing only yesterday. Funnily enough my mind leans towards making a donkey engine. I have plenty of material for it except the bed but if I took a leaf out of the Tangye designs and the later Yates and Thom engines where the trunk guides were circular and formed part of the bed I can get round that. Perhaps if I make a flywheel and shaft for it I shall be inspired! It would be a chunky little bugger, about a foot long overall....
Shed temperature isn't too bad, 46F at the moment and if I leave the door open from the kitchen while I am out having a walk it will get close to 50F and soon go up more as I work. More brass today..... The bucket of turnings for John is building up....

[Bodger]

What could you make with a rope and a mirror, British technology at its best!
http://www.britishpathe.com/video/teles ... y/wildcard
http://www.britishpathe.com/video/cave- ... y/wildcard

[Stanley]

Johnny made a 6" reflector telescope.... I shall not be going there!



It didn't take long to go through exactly the same steps as the other gland but a bit larger. Here's the check for size just before I parted it off.



I used the Doublejohn method of making sure the gland ran true before facing it and making sure the bore was chamfered.



Here's the finished article...



Next was some concentrated measuring up and a dig in the treasure chest for the materials... We are on to valve making now and all is ready to begin...

[Stanley]

I thought it might be a good time for a pic of the shed so I popped in this morning and did one.
Today has been valve making. Forget what Stuart's say on their drawing, Newton taught me a far better way of making a slide valve, I think originally it was Johnny who came up with it. Of course if you want to do it the traditional way you will ignore me but I have always made them this way and there are certain advantages. The valve is free floating, it's only held in place by the design. This means that you can make the valve rod rigid by making the guide for it. In addition, adjusting the valve is dead simple, you don't have to open the chest up and start fiddling with small nuts, all you do is uncouple the valve rod from its linkage and rotate it to move the valve. This limits you to half a turn at a time but with 26tpi on the thread into the valve driver this is quite small enough to get an accurate event. One half turn of the rod moves the valve 1/52". It will all become43 clear as we make it....



I started off being lucky, I found a sharp slitting saw in the tre4asure chest. Only problem was that I wanted to rotate the vice and it was fouling the holding down bolts. Now somewhere there are two bolts that work but I couldn't find them so I had to modify two to fit which all took time. Anyway I got there in the end and put my block of bronze under the saw. Easiest way to line it up is a ruler laid across the face ans away we go. The saw cut beautifully...



It didn't take long to get a slab 1" thick.



Then it didn't take long, two cuts, to reduce it nearer to milling size.



Close of play, we have a block that's getting close to a size, not going to need too much taken off in the VM. We're ready for making it into a valve!

[Stanley]

The first job was to look for some square sides. I used the fly cutter and it was fast, cut cool and chucked brass all over the p-lace!



Once I had two faces parallel I used this cutter to get a square face on the end using the configuration of the vice jaws.



Then I measured up and marked the dimensions I wanted.



next job is a 3/8" slot down the centre line deep enough to accept the valve rod.



Once I had that slot I needed another at right angles but deeper but leaving enough meat on the bottom to mill out the steam space. Some more careful measuring and marking.



Close of play, I've got my marks done and started milling out the cross slot. Don't worry if things haven't become clear yet, they will tomorrow!
Nice morning, no drama.....

[micktoon]

Hi Stanley , it looks like the last day of 2014 has gone well in the shed so hope 2015 will follow on in the same way I have not been in the garage as feeling rough, just not right some bug type thing that is going around so its a quiet night tonight too. Your milling is going well and the fly cutter has been worth making.
All the Best for New Year Stanley , may 2015 see many enjoyable days in the shed for you

Cheers Mick

[Stanley]

Same to you Mick! That stomach bug has been doing the rounds this Xmas I had a touch myself but my old immune system was obviously well on top of it....
Give my best to John and Bob. Onward and Upward!!

[Stanley]

Start of the morning. It didn't take long to complete the cutting of the cross slot in the valve body. I cleaned the slots up with a file but at this stage don't be tempted to do any finishing. In particular don't touch any of the edges associated with the face of the valve. It's essential that these are left as machined.



This is the point where you have to do some very careful measuring! Forget what the drawing says, it's essential that you mark the edges of the face of the valve according to what you machined into the face of the steam chest on the cylinder. You may not have machined the valve ports exactly to the drawing, so get your dimensions from the ports themselves. You have two dimensions, the longer side of the aperture is not as important as the ends but measure the width of the valve ports and make sure that the inner edge of the valve partially covers them. The outer edge is the seal between the steam space and the valve ports at all times. Remember that steam gets into the steam valve from outside the valve, all the aperture is for is managing the exhaust flow from the steam ports via the large port in the middle to atmosphere. The shorter size at the end is the most crucial. To get the dimension of the long axis measure the overall length between the outside edges of the steam ports and subtract the width of lone port. If you've done a half decent job they will be both the same. Needless to say both these dimensions have to be central on the face of the valve. If you've got everything right the width of the wall at each end is the same as, or slightly under, the width of the steam port. Remember that the edge on each side of this short wall is vital as it is the part of the valve that controls admission and exhaust events.



Check to make sure that your machine vice is dead square, no point messing up at this point!



Then some very careful cutting. At this point I had magnifying glasses and strong lights at the ready. High stress for a bloke that can't see!



Close of play. I think I have it right! Don't do any cleaning up in the aperture, it isn't necessary and you might damage the cutting edges of your valve. This is 3/32" deep and you might be tempted to go deeper, that's up to you but I know that this is perfectly adequate, you would be surprised how much steam a hole 1" wide X 3/32" can pass when it's open to the atmosphere.
Right, that's enough for the first day of the year....

[Stanley]

I realised this morning that I was so busy trying to explain how to get the dimensions for the aperture at the bottom of the valve that I got my calculations wrong. This valve will work OK but will need 1/2" travel on the eccentric instead of 3/8". I shall carry on but rework the internal dimensions yourselves and get it right! Sorry about that... the principles are right but the calculation was wrong. Just goes to show what a bum engineer I am!
On reflection this isn't a bad fault as the cylinder will have a very free exhaust. Sometimes you discover improvements via mistakes!

[Stanley]

This morning's job was to make the driving block for the valve, it has to fit exactly in the cross slot I milled yesterday but have enough play to float so that the valve can find its own seat. I think you've realised by now that the actual slide valve isn't attached in any way, it's just located by the valve rod and the driver block.
So pick a lump of bronze as near to the size as possible and do some marking and cutting. I ran the fly cutter at the same speed as the 3/8" end mill, 580rpm and it cut like a dream, cold and with chips flying all over the place but a lovely finish.



It didn't take long to get a size and here's the finished result.



Tomorrow we'll drill and tap for the valve rod and do some minimal finishing which will include grinding the seating face on the bottom.

[Stanley]

First job this morning was to vacuum up the brass chips my fly-cutter had flung all over the bench. Then a good sweep up of the lathe because we're moving back into steel turning and I want Doubleboost's scrap to be clean. Then a good root through the various material piles to find a short piece of 1/4" steel. Polish it up and prepare the end for threading.
Before I started on this I made sure that the rod fitted the gang of three 1/4" holes in the gland nut, the valve chest and the guide at the other end. You'll be very lucky if they are dead in line but that's no problem because the hole in the gland nut and in the wall of the chest can be safely opened up as they will be sealed by the packing when we get round to it.



We've got a good fit with only minimal opening up of the gland.



Then thread enough of the rod to cover the travel. No problems this time as the die holder is lined up properly. A dab of Trefolex to ease the job, my favourite threading compound for steel.



Next job was to mark the driving block with the end of the rod while it was in the gland. Pop it and drill tapping size for 1/4" X 26tpi in the drill press and without moving it. pop the tap in and get it almost all the way through. Then transfer to the vice to finish it off secure in the knowledge it is in line.



Close of play. We have a nicely threaded valve rod dead in line with the centre of the valve. You'll notice that theoretically, because the valve itself is floating and you haven't made your driving block tight in the valve it can float sideways as well as up and down. Don't worry about this because in practice it will always tend to be in the centre and will not deviate sideways enough to give any problems.

[Stanley]

I said this morning on 'Today I shall be mainly' that I was undecided. I made my mind up and here's the story.
The ballast for the bum kitchen light arrived yesterday so I got the lamp out of the hall and set about installing it. I was perturbed to find that instead of a block of 7 connectors at one end it only had 6. I went on the web but could find no answers. So I shifted the wiring from the old to the new ballast ignoring the spare wire, it worked! so I taped up the bare wire and stuffed it out of the way in the fitting. So, I had the good fitting ready for putting up in place of the temporary one which was destined for the shed. I was itching to do the job but knew it was a two handed job putting the fitting back in place. That was why I was undecided.
After a bit of thought I reckoned I was capable of taking the temporary fitting down and I could put up with the wait for Mo to come so I got the ladder and with great care climbed up and got it disconnected and down on the floor.
I had a look in the shed and decided I could put the new twin tube up over the bench by myself. I found two of those plasterboard screw fittings that expand in the void when you tighten them up and soon had the fitting fastened in place. I had been intending to wire it into the existing lighting circuit but then I had a better idea.
I have always had an old anglepoise mounted on the wall above the grinder and used that as a supplemental light for the bench. It took up a lot of room but was useful. It was wired via a plug onto a gang of sockets at the back of the bench with no switch, those sockets and the grinder were all on the same gang and were switched off when I left the shed. So there was no difference if I did away with the anglepoise, gave myself more room and tidied that corner up considerably. The lamp had always been a bit of a pain.
So I wired a plug to the new strip light and tried it out. Perfect, floods of light and it served the grinder as well. Only one small incident when I took the lamp down. I decided to lift the support out of its socket and deal with the mounting block separately. I hadn't realised how powerful the internal spring in the unit was and as I lifted it out of the socket the bars snapped shut trapping a fold of skin on my hand. It was bloody painful and if you could have seen me getting the vice open so I could grasp the support and put pressure on to open the bars and release my hand you would have had a good laugh!
However, I managed tidied the wire up down to the plug and then set about cleaning all the chips and plaster dust off the bench. I Hoovered the floor while I was at it and so I have a clean improved workshop with bags of light over the bench but no progress on the valve....

Here's the result....





I'm pleased. Less clutter, more light and a clean start for tomorrow. The message for Mo is that all we have to do when he has time is put the old fitting back up in the kitchen.

[Stanley]

Couldn't resist popping in the shed last night to gloat over my tidy, well lit workplace! I'm looking forward to getting in there today! A small thing but isn't it nice when you can get enthusiastic about something like this. Never a dull moment...

[Stanley]

What a nice clean, tidy well-lit start to the day. Incidentally, I noticed when I switch the new light off and we are left with just the old ones, it is incredibly gloomy!



My first job was to address the fact that the piston no longer fits in the bore. I used Doubleboost's ball bearing on a stick to get it running true. I wondered why it wasn't fitting because it did when I made it so I did a bit of checking. I had made it a bit too close fitting and the cylinder casting has moved a touch as the casting stresses come out after machining. It is a shade out of a true cylinder now. Nothing worth bothering about and anyway it will keep happening for a while. I just reduced the piston with a smooth file until it was a good fit.



Once that was sorted out I looked for materials in the treasure chest for a piston rod and a clevis for the valve rod. Then I checked my measurements.



One of the problems about a treasure chest full of scrap ends is that you are never quite sure what you are dealing with until you cut it. This was not free-cutting MS! The chips came off blue and I had to change cutters and re-sharpen a piece of HSS. Fine cuts and I was getting a finish. This rod will never wear out!



The final cut. Dead on 19/32", what I was going for. I cut the length off, squared the end, reduced it to 3/8" and put a chamfer on for the Whitworth thread. Then I hit my old problem, I had not got a 3/8" Whit die! I remembered why, being a cheapskate I always use a 3/8" UNC die because it is 16tpi the same as Whitworth. I think I might treat myself to a 3/8" Whit die!



Here's the piston on the finished rod.



The gland and the lid have good clearance, the piston and the rod fit the bore nicely.



The next job is a clevis for the end of the valve rod. I had found a piece of square key steel and so I swapped the three jaw for the 4 jaw SC chuck and we are ready for tomorrow....

[micktoon]

Hi Stanley , more good progress, and all looking very ship shape. I bet you are glad you have gone to the trouble of putting the new light up, funny when you do things like that then see how dim it was before the new addition was made, it makes you wonder how you managed. It has got to help the situation with your eyesight too.
Keep up the good work.
Cheers Mick.

[Stanley]

So much so that I want another 2X35watt over the Harrison!
Can you and John look through the boxes and see if you have a spare 3/8" Whit die? (These pensioners can be so demanding....)

[chinatyke]

I'm enjoying reading this thread and seeing the photos of your thingamajig taking shape even if I don't know the whys and the wherefores most of the time. It's wonderful to see you create pieces from simple rod and bar. A true craftsman at work. Well done.

[Stanley]

Nice of you to say so China. Funnily enough I never think of myself as a craftsman, all right I can make some nice stuff but I compare my work with much better men and women I have known and I still have a long way to go. I once sold a lathe to a bloke in the hills behind Hebden Bridge and when I delivered it he was making some small bits and they were coming off the lathe perfectly finished. I told him it made me feel like going home and scrapping my shed but he said I was wrong, the only reason he could do things like that was 40 years in the tool room and I had to give myself a break! I took notice, and I do.....