Here is a list of all the postings Richard Parsons has made in our forums. Click on a thread name to jump to the thread.
|Thread: Mystery Tool|
Yes it is a saw setter. I try to minimise my wood butchering but I have 3 saws which were as ‘blunt as a badger’s back end’. I also had some metal band saws that needed re welding (Hungarians will not be told how to use them and will insist on trying to force them to cut faster).
At the local Faripari works they welded the band saws no problem. Then Ii produced the old spear and Jackson panel saw. The foreman looked at it pinged it and smiled. He called over the others burbling in Hungarian to admire it. I then producer a little ‘Gent’s Saw’ which made him purr. And then my ‘tenant saw’ (by Tyzak Sons and Turner). The foreman and the others went into a sort of dreamy reverie and ‘Bloody Lad’ was sent to fetch the Boss, who appeared very quickly. For the next 10 or so minutes the whole lot were passing the saws around sort of caressing them. Then one produced an old violin bow and played tunes on the Spear and Jackson. They were then arguing who should sharpen which saw and through my wife explained they would have a problem setting them. I fished out the Tool (or one rather like it). There was then a long discussion as to what the numbers on it meant. In the end they got the idea that it was the number of teeth per inch. There is an old Hungarian measurement the ’Hülveyk’( which is converted to 25.4mm). it is still sometimes used by the oldest of ‘Gazsda’ and old barrel makers.
There was a discussion about the files to be used –theirs were knackered- so I slipped out two Valrobe 3 square files –one No 2 cut and one No 4 cut- I had bought a job lot of them somewhere for about £1.
Two weeks later we went over to collect them. The Boss greeted us and put the saws down for us to inspect. He then introduced someone (a very bulky person with hands full of gold rings) my wife recognised him and there was a long discussion (which I was left out of) about the Spear and Jackson which the stranger seemed to want. Wife struck a deal and large denomination notes passed in several directions. and my old Spear and Jackson was carefully wrapped up and taken away by the stranger.
I gave the foreman the tool which I will never use and the files. He stowed the remaining saws into my motor and bundled us out of the place. Later my wife explained what was going on. It was the problem of the boss’s commission on the sale of the saw and who was to pay it, and the foreman’s expenses for the tools. . On the way home my wife bought the lunch at a very expensive road house and gave me 30,000 forint to buy a new saw.
|Thread: Wheel Cuting thin tooth?|
|Peter Remember that using the rotary table the errors between individual holes are very small. But they accumulate. That is the error between each pair of holes is 0.005434” but the error between the first and third hole is 0.010868” and so on. It only shows up at on the very last tooth.|
|Thread: Hot Air Engines|
Hi Jim! A belated Happy New Year. I meant to E mail you but I went ‘arm over anchor’ just before Christmas. We had a small snow fall so I cleared it and gritted my steps. Problem was that my step daughter thought the grit looked nasty so she had the steps swept and scrubbed. It froze, I went ‘arm over anchor ‘in the dark down some 4 steps. I do not bounce as well as I used to. So I am still creaking around.
The Stirling engine I would like to build for a mate’s boat on Lake Balaton. I know that Stirling (external combustion) engines like to run at full speed; however with a variable pitch prop (Stuarts used to make them) it could be controlled (and reversed. I could get round all sorts of regulations which apply to the ‘Infernal Combustion’ engine used on the Lake. I must poke the ‘authorities’ with a sharpened stick on that one.
The problem I have is I do not know what size cylinder would give me the required output. My next door neighbour’s lad has just piled in a 2 cylinder ‘Qwakayamahonduki’ it looks a mess but I think the cylinders are still intact.
Can anyone give me a clue on that topic?
Ian Hi Happy New Year etc. It still seems to be a bit ‘shaky’ down your way, but I hope you are OK. There is another version of the rhombic drive. I have a book with it in but I have cannot find it at the moment. I think it does not use gears, but I am not certain.
|Thread: Wheel Cuting thin tooth?|
Peter have a look at your calculations for the rotary table.
Now 360/115 is 3.130434782608 ….. Degrees per hole.
How is your rotary table calibrated? What is the error per hole in terms of that value?.
Supposing your table allows you to measure to1/8th (0.125) of a degree. The second hole you drilled in your division plate would be 0.005434 etc of a degree out of position. The next hole would be 0.010868 of a degree inaccurate and so on for all 114 holes (the first hole is spot on) the accumulated error would be 0.619562 etc of a degree adrift.
Now the 115 divisions is 3° 7’ 49.565” of arc. If your rotary tables will allow you to get to 10’ of arc then the second hole would be 2.1739.. etc minutes of arc adrift. So after 114 holes the error would be 4.13043 degrees adrift.
But all is not lost. There is a very good way of making such a plate. Firstly you need a strip of thin steel. I use second hand metal case strapping. You then need to make a 2 hole drill jig with a suitable distance between holes and a pin which is a nice push fit into the holes on the jig. Use it to drill a hole in your strip. Move the hole you have just drilled to the second hole in the jig and drill another hole. Repeat this until you have drilled 116 holes. Measure the distance between the 1st and the last hole. This will give you the circumference of the loop you are going to make. Make a loop with the 116th hole lined up over the 1st hole and join things together. Now make a wooden disk whose diameter is that of the loop. I do this by rough sawing over size and then turn to size gently.
Ok now you have a drum of 115 holes. The holes will have errors of +-0.001” but this will not always be in the same direction and will tend to average things out!.
Hope it helps
Edited By Richard Parsons on 06/01/2012 06:02:02
|Thread: Hot Air Engines|
Hi Alan, I have long wanted to build a Phillips rhombic drive engine with a rollsock to develop about 3 to 3.5 bhp. I had the drawings but no clue as to size. I do not think that I would care to try where I am now. I have enough trouble collecting 8mm fine bolts to rebuild an almost new oriental bicycle.
I have just had a thought. If I can find an old 4 stroke single engine ( or just the cylinder of it) may be if I can drop my hand on a very small intermediate stainless milk cooler – or perhaps a cooking pot. The great Mr Rizo (of Malta) did a lot of work using mesh displacers. Hmm stuffed with kitchen foil –I can get that from the supermarket-. Problem is the roll sock this retains the pressure in the power cylinder/hot/cold end. So I can use an open crank case or one which is just muck proof. The gears for the rhombic drive could be pricey. Waite someone made a type of the rhombic using a form of 4 bar linkage. This allowed him to use the Phillips concentric power piston and displacer drive.
Problem is most of the good stuff was bought up years ago by Orientals with suitcases of cash.
Terryd Yes I know this but new clean oil costs money. Somewhere in my ancestors was one who came ‘frae Aberdeen’ since her name was Cohen one must draw your own conclusions. But they do not become more ‘careful’ than that. So as Wolfie says you just need to follow a 2 wheeled oil slick and you can get dirty oil for free. Seriously I think that there are various ‘chemicals’ in the dirty stuff that improve the blackening. That is why I always do it out of doors and to leeward of the house. These ‘chemicals are why I think the old ‘uns used whale oil. When using this technique the finer the finish on the item the finer the final coat will be.
BTW Woolfie has your friend never heard of a Kellogs Cornflakes (usual disclaimer). The packets (which are the best part of the whole thing) make almost bullet proof joint washers.
Wolfie as it is free get a bit of scrap and see. I think it may well work on rusty stuff but i have never tried
|Wolfi What are you blacking? Here is a dead cheap recipe which works on steel BUT as you will see from the method it is a bit crude.|
Get some Dirty motor oil –yes dirty!. Heat the thing to be blacked to a dull cherry red and plunge it into the dirty oil! When all the fuss has dies down and the thing is cool enough to wipe then wipe it. It is best to do the job outside and down wind .
|Thread: Lard Oil or it's modern day equvalent?|
Lard oil You can still get it. Basically it is the lighter fraction of pig fat. The ‘oil’ can be extracted by part melting and filtering. There is a sort of discussion about it here.
I seem to remember Mr. ‘Two dog’ Jones who made tower clocks for churches etc. He lived in out village used it. He mixed it with a tiny amount of Thymol to stop it going rancid. He used with a brush.
I ues Mobil Dortan 25 in a drip flask.
Happy New Year to all
|Thread: 20/40 DP gear hob|
Does anyone know where to find the ‘wire’ sizes for making involute cutters and hobs?
|Thread: Small Cutter Grinder|
Kevin … It all depends on what cutters you want to grind and how much you wish to grind off. For ordinary work like touching up lathe tools, drills, cold chisels etc. One of the first tools I bought was a small 6” offhand grinder. I still have it 65 years later. I now seldom use it. At one ME exhibition at Wimberley I bought two diamond coated files to do a job. They were a large flat file and a large rat tailed file. They were to straighten op some glass wear my mother in law had. I started to use these to ‘touch up’ lathe tools. I now have several diamond files and plates.
Drills I seldom break, but when I do I use the offhand grinder and true them up and finish them with a hone on a coarse diamond stone cutting plate. In the UK I could buy them for £2-£3. I run them in a small angle grinder (which someone had had binned) with a backing plate to stop the stone cutting plates from flexing.
In the late 1970s I bought my first vertical milling machine and then I made my tool grinder around 1980. Now I seldom use it. With a packet of Chinese diamond files and a bit of thought I can touch up an end mill by hand. I now use a trick written up by our good editor (David). This to touch the surface you are going to file with a felt tipped pen. It helps guide your filing. I know it is not as accurate as setting up a tool grinder but it is far quicker. Many of these tricks I learned at the SMAEE stand from Prof Chaddok.
Most of the complex equipment we have for sharpening things was designed for de-skilling and speeding the job up. If we have to do a ‘one off’ it is often better to do it by a bit of thought and by hand.
Oh by the way it is illegal to change a grinding wheel unless you have a certificate issued by your local authority.
Kevin… Have a look at this posting. Have a browse through the beginning. The Kennet is a simple but useful machine. The techniques used are very good and simple. I was going to use them to make a machine I have always coveted a Box Planer. I live in Hungary where the business men have discovered the ‘Minimum Order Quantity’. I could buy what I needed but only in 50 X1 litre cans. Their reason was we will not want ‘break bulk’ uram (sir). I was in their stores and could see the stuff was supplied in packs of 12 (4X3). They did not want to sell the stuff to a private individual. You want to hear (or rather do not the) rigmarole and paper work involved in buying planed timber –even when it is offered for sale in the racks as planed.
Rdgs and a Happy New Year
|Thread: Bearing Material|
In one place I worked we had ‘a large number of ‘Singer’ sewing machines. These worked some 8 hours per day 5 to 6 days a week doing all sorts of tasks ranging from hemming mattress tops to sewing complicated feather quits. The seldom went wrong. Their shafts were slightly hardened shafts in Meechnite cast iron bearings. All of their drivers (machinists oiled them religiously before they went home. Some dated from the late thirties and some were supplied under lease-lend. They were all destroyed in a fire one night set off by an arsonist.
|Thread: 3 phase motor connections|
Hi Peter Did your lathe come with any switch gear. As I remember it 3 phase motor usually had a ‘Memota’ (a trade name) switch. You pressed the green button and the rest was automatic.
Motor was started as ‘Star’. After the starting surge died down and the motor came upto speed; the ‘Memota’ type unit automatically switched the wiring into Delta. Star takes a lot of current and spins the motor up to speed changing it into Delta reduces the current flow and the motor then cruises doing its work.
|Thread: Was this the birth of CNC ?|
Billy you are right the Antikythera was a mechanism to replicate planetary motion and to provide corrections to sundials used to set the public water clocks. It is not the only example of such an apparatus in existence. There is Richard of Wallingford’s celestial clock, which he never finished, but has been made as a modern replica. There is also the great clock in Prague and hordes of others. None of these are computers in the true modern sense of the word but are mechanical simulations of the situation as we understand it. It of course is incomplete in the same way that when you think that float glass is flat. It is not as I learned when I used a piece as an optical flat in an 8” Newtonian telescope. Float glass is actually a spherical whose radius is that of the earth where it was made.
I had fun once with the corrections to a form of gyroscope. This thing was mounted on a large steel tube which went down into the bed rock. It used to display movement and seemed to be slowly moving in one direction. They had taken the earth’s movements around the sun but had forgotten earth’s precession or the earth orbit round the sun and the wobble of the earth’s axis. My programmer had the vapours over that one. The corrections were added to the program but it still showed drift. Not acceptable to the customer. I had to do a lot of digging into astronomy and found that the sun its self was moving through space. New corrections were added and the thing settled down to be within the experimental error. The customer bought the system but not the program. We can write that ourselves they said. Result -2 years later the sued us for the program specification and lost the day. The bought at a huge cost both the program, its specification and support from the Executive in Electronic Information Organisation. Yes assistant analyst was the EIEIO!
Billy I will agree with you about the wheels on the Home Pointing Chariot. The Chinese were very good craftsmen. They knew about both the Compass plane and the lathe so there was no problem over wheel sizes. The main cause of errors with the chariot was bumps in the road, but these generally averaged themselves out. The chariots would be deployed in ‘foreign’ or ‘enemy’ territory.
They used lodestones yes but they did not understand the problems of Magnetic Variation. which is something the Hungarians do not know either.
Have a look at the Beijing Ancient Observatory. Although this place is quite late on, the mid 1400s, it was very accurate. It had one of the world’s first seismographs for providing the authorities with information about earthquakes (for disaster relief). Its main use was for providing accurate information for astrological.
The chariot could be (and probably) was re-aligned by either the noon day sun or Polaris. One should remember that 20 miles was a long day’s march and that a rapidly advancing army would make on average only some 6 to 8 miles per day.
Stub Here is a very nice example of Heron’s Aeolipile. What I want to find out about is the levitating chariot. Or was it a trick?
Heron was employed to make worshipers in the various temples go Oh-Ah! and incidentally put coins in the collection boxes.
The Greeks knew about static electricity and the Babylonians built batteries. Even the word Electron is the Greek name for Amber.
If you want to talk about computers how about the Antikythera here
Heron of Alexandria was employed in the Department of Applied Miracles by the Association of Local Temples. His Aeolipile was interesting but of low power. I have seen an example of it made from a beer can using a nail to punch the holes and as bearings
A form of it was used to turn a set of dancers which may have been very similar to the Zoetrope a very early machine which creates the illusion of movements. He was made the famous Automatic Bird Garden.
Some of his work was based on a ‘Wash and Brush’ up machine for use in temples. It was inventedby Philo of ByzantiumYou poped a coin into it and a hand gave you a lump of soap/pumice. After a little delay it filled a bowl with water so you could wash your hands.
I will not go into old Leonardo’s Lion. Nor the home pointing chariot invented by the Chinese which was basically just a differential gear
I think that Heron’s use of string, rollers and pegs really takes the biscuit. I might make something as I can get wood, nails and string.
|Thread: Back Issue MEW Wanted|
The copy you want is in the MEW Online Archive (if you have a subscription)
DAVID There is an ‘error on page’ in Issue No 50. I suggest next time you visit the place where these scans are prepared and loaded, you take two house bricks with you and remind those who do the work about “camels”
|Thread: Was this the birth of CNC ?|
Have a look at this – Not bad for 50 AD. Think what old Heron could have done with a better power unit!
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