SHED MATTERS 2

[Stanley]

This morning's task is to make the piston for Sarah's cylinder. Everything was set up so I got stuck into it and soon had it made.



A bit later.... Both cylinders have pistons, marked Debs and Sarah so there are no mix ups. I also cleaned up the lids on the lubricators so they look nice.



The sideboard in the kitchen is looking busy! There are two engines here and while there is a lot to do yet we are getting there! The bad news for Mick and John is that I can't go any further now without either making work or doing a lot of guessing so this is it until I get the remainder of the castings.....



When I took the remains of the piston stock back to the treasure chest I had a furtle and found this slab of bronze. I can get the crank bearings out of this. I considered starting to straighten it up ready for use but then decided against it. I need to get some proper measurements before I invest time and material into what could be the wrong size. Instead I decided to do another little job that's been on my mind....



First I had a good clean up and tool tidying session. Then I got this spirit level out and set about checking the level of the lathe. I've been noticing for a while that I have been getting a bit of a taper while turning jobs in the chuck, not between centres. This is either misalignment of the headstock on the ways (not possible as nothing has been touched) or most likely, a twist in the lathe bed due to settling. I haven't checked it for over 15 years. This level is just the tool for the job, it's extremely sensitive. Notice that I have used a couple of parallels to mount the level on so as to get a direct reading off the flat parts of the ways.
I was correct in my assumption, the whole machine was leaning back slightly and the tail end was further out than the head end. It took about half an hour to get it dead level, both across the ways and along the length. The next time I am turning anything in the chuck alone I shall make sure I do some careful measuring but I'm fairly certain that I will have cured it. The Harrison is a good lathe and was built accurately, all it was asking for was to be set level on the floor! By the way, I checked the Stabila magnetic level that I use all the time against this one and it's dead accurate.
During the course of doing this I had to do a lot of getting down on the floor to get to the adjusting screws and then getting up again, a big thing for me these days! However, I managed and was pleased that my back wasn't hurting too much. I think I might be on the mend!

[Stanley]

Not too sure about my assessment of my back yesterday. It is as bad as ever this morning.....
I've had a think and I could make the eccentrics for the engines.... Will take a view later in the day.

[Stanley]

The eccentrics won. I did a bit of measuring, went into the drawing office and produced a couple of fag packet drawings. Then off into the treasure chests to find some stock. I've run out of those lovely square risers that Dick Bonser cast for me so I'm into the cast bronze. Question is, will I run out of stock before I die? Worrying stuff! I need to slice some chunks....



I moved the compressor out of the way and brought Mrs McMaster out to play. (The best thing that ever came out of the NE! Thanks lads....) First I cut the steel for the actual eccentric.



I didn't stand round scratching my bum while I was waiting for the cuts. I decided to test the result of my adjustments to the lathe yesterday. I got a piece of rough scrap shaft out of the box and made it into a good piece of stock. I love rescue jobs like this! It's material for nothing!



A few cuts later and I had a clean surface. I tested it with the indicator, it's an unsupported 4" cut and is dead parallel, the same measurement at each end. So I wasn't wasting my time yesterday. Well pleased.... All Mrs Harrison needed was a chance!



While this was going on I got the steel cut and started on cutting the bronze slices I need for the eccentric strap. The bronze is a lot slower cut than the steel and this is where I had got to with the first slice at knocking off time. I'll finish cutting them tomorrow....

[Stanley]

I don't want to be hanging about waiting for the saw this morning. What I should do is put a new blade in for bronze, it cuts slowly because it is so soft, the blade likes something hard to bite into. But I cheat.... I've put this 14lbs weight on the beam.... It's cutting now as I sit here. No danger of upsetting the neighbours, Mrs McMaster is very quiet!
06:00. I have always been a miser with hacksaw blades, I tend to use them until they are almost dead smooth! Silly really when I have sharp replacements in the drawer, I will not live forever, might as well use them! Besides, it costs more in leccy if the blade isn't cutting. So I have put a new blade in the saw and it's cutting properly now, many times faster than the old one! I will not be held up waiting for it to finish its cut when I go in the shed.
When I have finished cutting this bronze I'll put the original back in because it's fine on steel..... (Waste not want not!)

[Stanley]

The new blade soon cut the bronze slices, the old one is still good for steel so I put it back in the saw. So I have the measurements and the stock, all I need to do is make the eccentrics. The lathe has steel chips on the bed so I'll do the steel first.



A while later, I wasn't rushing. we have one eccentric partly finished. It has to go in the 4 jaw next so I set to to bring the second one to the same stage.



Come closing time I was into the second one. No rush so I knocked off here. I know exactly what I am doing tomorrow!

[Stanley]

Mick has been busy and the revised patterns are done and awaiting casting.







Lovely, if the castings are as good as the patterns they will hardly need any machining. Amazing the skills John and Mick share.... I shame to say I have been demanding and I have asked for three sets of the castings and an extra cylinder. I am looking beyond these two engines and fancy making one for myself but a slightly different design..... (I know, I am taking advantage.....)

[Stanley]

Fed up with the nasty stringy swarf I was making because I had neglected the shape of my cutter I ground the end off, put a chip-breaking groove in and resharpened it. Complete cure and I carried on looking for the 1.25" boss making curly little broken chips....



I soon had that done and the pairs of centres in each end and took the 3 jaw off. I turned the end of this silver steel held in the collet chuck to make an accurate centre.



The first eccentric mounted in the chuck and being turned.



By closing time I had the first eccentric made and ready for its groove for the strap. A touch smaller diameter than I was aiming for but it's OK. What you have to watch for is that when you bore it for fitting on the shaft the bore doesn't break into the groove for the strap. Easy to do! This is why the eccentric end of the crankshaft is smaller than the flywheel end at 1/2". I'll cut the groove for the strap tomorrow, no rush.....

[Stanley]

I don't know how much I'll get done today because I have to get scrubbed up for Billy Parson's funeral at 13:00.
I was thinking about tool shape. It's all down to Newton actually. He was brought up in the days of treadle lathes and the aim of the turner was to make the tool cut with as little effort as possible. The route to this is very sharp honed tools and a lot of rake behind the cutting edge. Completely contrary to modern practice where they are looking for maximum removal rates to get efficiency and power isn't a problem. Indeed many modern ceramic tips run on negative rake which the old turners would never have considered. When Newton got to full sized lathes the steep rake persisted to some extent, they used to have competitions to see who could make the longest unbroken swarf string. Cleaning up was no problem, they had a labourer! I shall stick with the steep angle for some jobs but I must get into the habit of doing what I did yesterday........

[Stanley]

Busy morning.... I had to polish my shoes and assemble my funeral clobber. That done I was in the shed at 8AM and started where I had left off, I sharpened my grooving tool, the one with the notch that I used for crankshaft turning, and put the groove in the eccentric for the strap. Then some filing and polishing....



and one of the eccentrics ready for boring and its set screws.... I checked and when I bore it 1/2" for the shaft the bore will clear the bottom of the groove for the strap.



I set the second eccentric in the chuck and did it all again. (The advantage of making two engines at once!)



It didn't take long to get the second one made and polished. There was one small glitch in that I hadn't as much meat in the blank for the eccentric as the first one, so the groove for the strap is more shallow. This is because I was a bit out with my centre I think but it still has 1/2" throw and the bore won't interfere with the groove. It will be OK.



It was time to knock off and get my act together so I did a quick clean up, put the 4 jaw away and installed my Polish 3 jaw just for a change. I'm ready to bore for the shaft but want to check my measurements first so I am leaving this until tomorrow. Now for the transformation scene....

[micktoon]

Hi Stanley, hope the funeral went ok. More good progress on the eccentrics, its all coming together nicely as you say doing two at the same time has its advantages. At least you should be well practiced once you get your third set of castings to make your own engine
Cheers Mick

[Stanley]

You're right.... What isn't immediately obvious though is the fact that in this design I have given myself so much leeway that I can retrieve mistakes..... Good luck with the weather and the casting!

[Stanley]

I was not in a rush today, having an easy day after the funeral.... My aim was to bore the two eccentrics, make sure they fitted their shafts and pop the two grub screws in each that will lock them to the shaft when we get round to valve setting. So I gathered the troops, the 1/2" standard, and a Brown and Sharpe mike that I don't normally use but really like...



I drilled and then reamed to 1/2" and was a bit short of a fit, the shafts are .501" and .502". Dead easy, put a boring tool in and take a skim.... But then I remembered how I always feel for the readers who haven't spent half their lives collecting tackle and who must spit blood sometimes when they see me delve into a drawer and produce the most esoteric drills and taps or some obscure tool I have been nursing for years. So I asked myself what would such a person do? I worked through all the combinations of different drill series and lapping and couldn't see an easy way out.



Dead on 1/2", the standard says so....



Well, at least I thought about you. I soon had it sorted. Then I did the second and this time I forced the 1/2" drill through the bore left by the 1/4" pilot drill and it was exactly right, 2thou over 1/2". It was knocking off time, I'll put the set screws in tomorrow and then start on the straps.
By the way, two things.... The bore hasn't interfered with the groove for the strap which would have been a disaster. Remember me sorting the leak out on the airline? I only need to run it every couple of days, it holds it's pressure almost perfectly. Nice!



Both eccentrics marked for their engine.....

[Stanley]

In the shed at 07:00 and I want to be out early so I can have a sleep before watching F1. I also want to rest my back. So, the first task is to fit the grub screws in the eccentrics. I sammed all the troops up....



Then into the compound vice under the pillar drill for the usual round of setting up, centre drill, tapping drill and tap all on the same setting. Two grub screws for each eccentric.



The two fitted with their screws and all the tackle put away.



The next job is to start on the eccentric straps and the first task is to get them both turned parallel and the right thickness to fit the eccentrics.



Away we go, a dead simple job. No need to worry about the periphery as a lot of metal will have to be cut out.



By 9AM both discs finished to the same thickness and I knocked off.
By the way. I put the indicator on the face and it's dead square. The taper I was getting before I levelled Mrs Harrison would be affecting the face as well. The other thing you may have noticed is the empty Sparklets CO2 bulb lay on the bench. I picked it up in the street on Friday and when I have time I want to find out how they makes them!

[Tripps]

"the empty Sparklets CO2 bulb lay on the bench"

Are you sure that's what it is? I saw a cluster of these, discarded in the butcher's car park last year. I'd guess they were more likely to have contained nitrous oxide.

[Stanley]

Could be David but whatever it contained here's how they make them....

LINK

[Stanley]

A quiet morning. I'd had a think and decided how I was going to make the straps.... First thing was to bore them 1 3/16", just short of what they will have to be. Centre drill, 1/4" pilot then a drill to take them to full size.



Bored and ready for a clean up of the periphery. Notice that the big drill has had its cutting edges backed off to stop it grabbing.



A bit of sacrilege here. The nose of the jaws was slightly too big to go in the hole in the blank and of course wasn't round. I put a carbide tool in and took a fraction off the corners.... At the same time I cleaned the nose of the jaws up....



It fits now.....



I soon had the blanks cleaned up, edges broken and then I wanted a converter so I could mount the disc on the rotary table for machining. Remember the piece of scrap shaft I rescued? I used a piece of that. Ready for mounting up on the rotary table....



Just one more thing.... I blued the blanks so they'll be perfectly dry tomorrow.....

[Stanley]

I forgot to mention that I harvested John's non ferocious chips, we have a good weight ready for him....
The design committee has been busy working out how best to mark out the straps. I am having to rethink my usual methods because this is the first time I have made the straps out of round stock, I had a bunch of castings for this size of strap but have used them all up. Not a big problem but it makes me use the old grey matter more!

[Stanley]

First job was some very careful measuring and marking out. I want to be quite clear where I need to remove metal! By the way, you can't have too much layout gear!



Then I fitted the rotary table and centred it using the set screw with the pip. Once I was sure it was right I locked the Y axis, not sure if that's right, the one that shifts the table back to front!



Then find a sharp cutter and get set up.



I soon got into serious trouble, the cutter grabbed, spun the workpiece loose and I was lucky not to have a breakage so I decided I needed a different approach. Instead of taking a series of circular cuts I got the cutter mounted so it was cutting on the circle and made a series of plunge cuts. Much quicker metal shifting and perfectly safe. The table keeps me on the right arc and when I have that section done I cleaned it up with a continuous circular cut but very light so I didn't grab.



It didn't take long after that to finish the first strap off, clean up, mount the second and take the first cut.



Here's the first one ready for a bit of old fashioned filing. I was very tired, I think because of trying to hold my back straight so I knocked off half an hour early.... No rush!

[Stanley]

I've not torn any trees up this morning but made some solid progress even though my back is not playing the game, it's hurting when I'm on my feet now! Boring I know but that's the sitrep. I started this morning by finishing the roughing out I started yesterday and then cleaned up, took the rotary table off the bed and set the normal milling vise up. When I said old fashioned filing yesterday I wasn't thinking straight..... So here we are set up for milling the straight edges on the lugs of the straps.



Not long afterwards I had got here. They are beginning to look like eccentric straps now. The next move is to fit the bolts in the lugs, split the straps, reassemble using the bolts and turn the centre hole to the correct fit for the barrel of the eccentric. I'd had enough at this point so I knocked off. I'm satisfied for this morning.....

[Stanley]

I need to drill the holes for the bolts that will hold the two halves of the eccentric together when they are in place so that was the first job this morning. 3/16" which is clearance for 2BA.



2BA bolts dropped in to check the holes.



Straight into the vise and set up for sawing them in two, both eccentrics mounted together.



I started cutting and then realised I was making a mistake. I need the faces of the two lugs to be square so that I can mount the eccentrics in the two jaw chuck for boring so a quick change round and mill the faces off flat. Narrow escape! It would have been a lot harder without the flats.



That's better. I can saw them in two now!



Getting there. Both eccentrics cleaned up and fitted with the bolts that will be with them for the rest of their lives. The eccentrics are marked for Sarah and Deborah as register marks and because they are slightly different in diameter.



A quick vacuum round, put the saw away and clean up. Change the 3 jaw for the brass chuck and set the first eccentric up for boring.



Knocking off time. The eccentric set up, the boring bar checked and ready. We know what we are doing tomorrow!

[micktoon]

Hi Stanley, more top class work Are you not off on Good Friday then ?, you will have to pay yourself double time if you are not careful ! The plan is to have a casting session on Sunday so hopefully we should get all the rest of the castings done including another cylinder with parts for you to do an engine for yourself too. Fingers crossed for good weather on Sunday.
Keep up the good work , Mick

[Stanley]

Thanks for that Mick. It's going OK, quietly and slowly and no cock-ups as yet. I have a good weight of Non Ferocious for John now, it will make his stocks up! Good luck with the castings. I have a Cunning Plan to keep me going when I have finished the two eccentrics which won't be long now so don't go into a decline if you are rained off....
One thing I forgot to say yesterday.... Look at the first pic. If you are just starting to build a shed and you have got your pillar drill seek out a compound vise for the table. In terms of usefulness it is the best accessory in the shed!
Good Friday is the same as any other day, a chance to play out in the shed! I love what I'm doing, there is a lot of satisfaction in finding the part lurking inside that lump of scrap! Same as your sculpture Mick. How is the soldier going on? We haven't seen him for a while....

[Stanley]

The job this morning was to bore the two eccentric straps and fit them. Measuring tackle out, bit sharpened in the heavy boring bar, centre height checked and the mounting of the strap in the chuck given a last check.



Away we go, frequent measuring!



Sarah's was soon done and checked by fitting it on its eccentric. Debs gets straightened up in the chuck using the old ball bearing trick.



It didn't take long. I forgot to do a pic of them fitted but they are both OK and not too tight.



This is a good time to put the oil hole in. Centre drill to make a cup and then poke a 1/8" drill through.



Then I filled the time in until closing time breaking the edges on the straps with a smooth file. Tomorrow we'll make the faces look pretty.....

[Stanley]

Something that has been bugging me is that the sides of the lugs where the valve rod will be mounted aren't perfectly square so I set out to put that right.



I allowed myself to be diverted into giving my best friend, the 6" Parkinson's Perfect Vise, a good clean and oil up. These things get forgotten....



Then back to my onions.... I soon had the lugs looking as though they belong......



I stuck a sheet of abrasive on to the surface plate and rubbed the faces down until they were looking respectable. Then I broke all the edges again and did some careful marking out for the 2BA stud holes which will hold the valve rod.



Then I got all the tackle sammed up, tapping drill, tap and the four 2BA studs I will need. The studs were all rounded and the 2BA die run down them to make sure they were all a free start and running. Saves a lot of time later on!



The high tech depth gauge fitted to the tapping drill.



Under the drill for making and tapping the stud holes. Don't be tempted to skip any stages! Each hole is centre drilled to spot the location and then drilled and tapped on the same setting. It's boring I know, all those chucking changes but if you make a mistake here it will come back to bite you later on!



A bit later. Funny how you can tell they are right at a glance... In case you're wondering what the roller bearing is doing on the plate. I tripped over it while looking for something else. Bearing shells make good parallels and all mine have disappeared over the years.



The eccentrics sat on their respective shafts waiting for further developments. Another step forward!



I had a clean up and then cut the cage that held the rollers. Two useful parallels and a set of 6mm rollers, all dead square, accurate and hardened. They will come in useful. That was it, I've done enough for the day. I took Jack for his late morning walk and the rain hasn't come in yet. Mick and John will be casting tomorrow. Fear not lads, no pressure, I have a Cunning Plan to make some more work on the engines! But that's for tomorrow......

[Stanley]

The Design Committee has been working on the Cunning Plan all night and I think we have it straight now. A smart move that will ensure greater accuracy and give me enough work to keep me going until the castings arrive. I like it!
With luck and good weather the lads will be sweating over the furnace today..... Great to have skilled and generous friends. (It remains to be seen how many of my requests for additional tools have stuck in their collective heads!) Any chance of Mick bringing me his Bridgeport Mill as a present?. (Dream on Stanley!)