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Member postings for Richard Parsons

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: Aircraft General Discussion
09/05/2012 16:47:45

Had a problem double posted



Edited By Richard Parsons on 09/05/2012 16:53:40

09/05/2012 16:47:18

Ian I do hope that the 'Annie' they are restoring has the power underxart. I beleive the Mk 1 required 120 turns of a handle to raise or lower the undercart.


'She was tattered she was torn and her fabric badly worn'
but her ole Cheeter 10s fired now and then etc - I will nor go on



Thread: Expert projects
29/04/2012 11:34:52

The muff gun written up in ME dated to the middle 1850s. The ones I am on about dates back to the 1490s. This was a time when the armours of Germany and Italy were at their peak. Every great lord would have several ‘tin suits’ –‘plate armour’- which was finely ‘glacis’ and hardened to give protection against the dreaded English and their long bows.

These would range from the suits of Jousting Armour which had very heavy protection in certain parts through lighter armour for use in battle which came in two forms horseback armour and armour for fighting on foot to the fabulous parade armour in exotic designs.. As a side note they were based in the area of south and eastern Bavaria which are exactly the same areas that became the centres of car manufacture in the 20th centenary ie. Companies like ’MAN’ (Maschinenfabrik Augsburg-Nürnberg). And in Italy in the districts of Milan and Brescia (Alfa-Romeo and Fiat etc).

At sometime in the 1400s ‘guns’ were found to be of great use especially by the Hussites of Bohemia. These folk used hand held guns, in infantry with wagons in formations called Wagonburg. A simple Hussite (like his English opposite number –a Long Bowman) could take out several heavily armoured knights whose armour cost many thousands of times more gold than the Hussite would ever see in his whole life. These guns were fired by slow matches. The serpentine lock was developed to make life easier for hand gunners.

Walking around with a length of lighted slow match (even on your hat) was not too good an idea (especially if you were rich and had an expensive hat). A smoking hat was not something to make you welcome in a beer hall! So sometime between the 1490s and the 1510 the ‘wheel lock’ appeared. It is this mechanism with all its subtleties which I find appealing. It seems to have been developed from two ideas, the ‘Monks Gun’ and a fairly common idea of using a hand wound wheel and the soft iron pyrites for making sparks to light fires. In Bavaria native flint is rare.

The Gunsmiths of Augsburg, Nuremberg and later Mannerheim and Brescia (in Italy) demonstrated their skills by making small Muff Guns for the town watchmen to carry in their muffs. These were sometimes called ‘Puffers’ and were about the size of a box of Swan-Vesta matches. By their design they could be carried about fully loaded with reasonably safely. It is their ‘lock work' which is complicated and is an artificers dream (or nightmare).

I do not want to talk about details of them any more on this (or any other public forum) as some folk may get the wrong idea. Mind you if you have worked for several hundred hours making just the lock, figuring out the solutions to all the problems the old ones solved and re learning their skills of fitting things as closely as they had. Then getting the confounded thing to spin and then to make sparks you will have achieved something.

I am quite prepared to e-mail a few remarks on the lock’s construction to act as a ‘sickener’ to those who want it and later if that does not put you off to I will go on with the correspondence.



Thread: Lock Problems
28/04/2012 12:46:24

Stub Mandrel Now is your chance to become a 'lock smith'. If you have two keys check them for wear, first by eye and second by measuring. Remember that locks are moderately precision bits of work. In a lever lock there are two bits which protect the bolt. The first are the 'baffles' which take the form of cylinders which if the key does not have corresponding groves in it you cannot turn the key, The second part of the protection are the 'levers'.these have narrow cutouts on them. Lift them too high or not high enough and they stop the bolt from moving..

What can go wrong? Broken springs on the levers, wear causing ridges inside the levers, damaged baffles. wear to the keys and the key axle bearing scuffing in the sliding surfaces, lack of luberication etc.

To cure dismantle the lock carefully watch out for the springs. I always number the levers so i can put them back in the right orders and when you do lubricate them well. Get rid of burs and straighten up baffles etc.

Locks are fascinating things designed to work for years with complete neglect. Clearances are quite large to allow for wear.

PS how do I know My house builders fitted the cheapest of the cheap locks so I often have to attend to then to get some one out of the 'kahazi' and then re-engineer the door

Good luck



Thread: Piston Valves
26/04/2012 15:20:53

Will before you make your decision to go ahead have a look at the design of ports and pistons used by the Hydraulics people. Here 'O' rings are used a-pleanty and last for many hundreds of thousands of operations. the ports however consist of rows of small holes each row is close to its neighbours and are staggered. There was a 'letter to the editor' in ME some years ago to which our good editor added a complimentary comment about learning from others.



Thread: Expert projects
23/04/2012 08:11:07

Michael Yes I have asked my daughter in the U.K. to take a pic of the thing. I am writing something on the subject which i will PM to you. I do not want publish anything on the open pages as the whole subject is almost taboo in the U.K.

The wheel lock is a fasinating mechanism which vithualy dissapeard by the mid 17 Ce (1640s).

It is a simple idea but is complicated to make when compared with the flint and steel locks of the period. The sparks in the wheel lock were generated from a lump of pyrites not from flints.



22/04/2012 17:57:09

Michael may I suggest any project which introduces you to new skills and techniques you have never encountered before. My great challenge has been to make a self spanning wheel lock for a ‘muff gun’ from Mannerheim of about 1430. These were miniature pistols carried by members of the City Watch in their muffs. They are tricky little beastie which include springs, chains, wood carving, inlay work including gold touch marks (optional) and a good deal of experimental fitting. They were originally made by the local craftsmen to show off their skills and they are about the size of a box of Swan Vestas. They were also made in Nuremberg. You cannot get drawings (photos yes) and often all you can do is to look at them in a museum collection. I was once allowed to handle one in a private collection but that was long ago.

Remember the original craftsmen probably did not have drawings either

If you want more please PM me



Thread: lathe wiring
22/04/2012 17:28:56


Shaun I will agree with David. Get yourself a real professional to do the job, not an ordinary domestic wireman.

But to help you understand what is going on, your motor is an AC induction motor (AKA a ‘Squirrel Cage’ motor). These basically have two sets of winding (Coils). These are ‘Running windings’ (often called A1 and A2) and the ‘Starting windings’ (often called Z1 and Z2).

From your ‘lettering’ I think you have a motor with a centrifugal switch and a (perhaps a capacitator). The extra wire takes power to this switch which opens cutting off power to the starting windings which are no longer needed.

The Dewhurst (Drum) switch is joined to the motor by four wires (PLUS THE EARTH). In the switch there are 8 numbered screws in the switch the basic plan is as follows

Line in (brown) =1

Neutral in (blue) =3

Start winding (z1) = 2

Start winding (z2) =6

Run winding (a1) =7

Run winding (a2) =5

4 & 8 not used


To reverse the motor, the Dewhurst switch reverses the feed to the starting windings. So if to run the motor clockwise the switch would connect say Z1 to ‘Line in’ and Z2 to ‘Neutral in’. To run it anti clockwise the switch will connect Z2 to ‘Line in’ and Z1 to ‘Neutral in.

If when the switch is wired in and it runs the wrong way (it runs reverse when the thing points to forward there are two things you can do. The correct thing is to swap the wire into Z1 to Z2 and Z2 to Z1 i.e. swap wires to screw 2 and 6 over, but there is another trick which is to unscrew the handle and put it back in from the other side

With the Dewhurst you should have a simple stop start switch as the Dewhurst is only a reverser not a start stop unit.



Edited By Richard Parsons on 22/04/2012 17:31:54

Thread: A useful Stirling engine.
21/04/2012 07:51:32

Lyric I agree with you but the question was put



20/04/2012 14:33:42

Terry    I am only here for the beer, baccy (I can buy a very good Cavendish at a price I can afford), wine and for the fact that as they cannot talk to me they generally leave me alone.  If they annoy me I tend to speak in the dialect of either of my early child hood  (Cockney) or my later childhood Cotswold with its "Oh Arr, Arr, buggerit, bist jonnuk? 'this yer hookem',  and universal 'Didder?' "

The Hungarians en-mass have other concerns on their mind, like a 93 year old treaty. Their unwillingness to work efficiently dates back to the Communist period when 'They pretend to pay us so we pretend to work!' and old habits die hard. Their general attitudes are in part caused by their language which is very complex and you can only really learn as a child (it is not an Indo European language) Because of this they are very 'insular' and belive that they are very superior to their minorities (the Roma) and to the rest of the world.  They will never accept blame for their failures.  Their fellow Hungarian speakers who live as minorities in other lands (Romania, Slovakia Serbia etc.) are very different as they have been exposed to and live with strangers on a very large scale. But as one French Generals said "Les Hongoise sont enfants charment". (The Hungarians are charming children). The suppliers are uncooperative because again of their (communist) past . Very few have learned that their customers are important, but most do not . Nor do they understand the ideas of honest dealings and competition. Most of them will only do as much as their local competitors, very few will go the extra inch .  If they can cheat you they are cleverer than you.

In the UK the Goblins of HSE claim that 'hobbies' are 'within their bailiwick' and 'you will have to prove your hobby aint'.



Edited By Richard Parsons on 20/04/2012 14:47:53

20/04/2012 08:36:09

Lyric Yes but I have got hold of two stainless mugs which when I have gotten the handles off seem fit into each other. But this is due to the ‘draft’ on them. I will have to spin the inner one down a might so it will not jam as it bottoms or tops out depending the way you look at it. My real worry is going to be if the stainless can be silver soldered. I do not know this yet.

I am still looking for ‘catering tins’ to make the diaphragm out of. The problem here will be can I actually eat the contents of the tin before it goes bad or I sicken of it.

Luckily I am beyond the reach of the Goblins and Gnomes of Elfinsafety. In the UK these folk will not allow hand held tools (any more). They made threatening noises about the use of the graver tool rest on a 6mm Lorch

At the moment I am just collecting the materials. Summer time is when I do that ,as most of my days are spent sorting out the broken mowers and strimmers etc. Hungarians are in the main ‘one man’ demolition experts. They can, and do, break anything (and everything). It is deeply ingrained in their psyche. If you can break the tool you do not have to do the work and they will spend an hour trying to bust their tools instead of doing a 10 minute job of work using them.

Finally there is another way. It was invented by (I think) ‘Tubal Cain’. It consisted of an aluminium pressure cooking pot (a bit beefed up). This became the boiler. Packed inside it was a S.T. ‘Sirius’ or a ‘Sun’ and a motorbike dynamo plus pipes etc. These were dropped to the French Resistance (the Maquis) and others to let them recharge their radio batteries whilst in the ‘bush’.



18/04/2012 18:28:30

Last night I was sitting enjoying about ½ litres of something golden, cool and very refreshing. I was running a ‘to do’ list through my head when suddenly I realised that I was a ‘damned old fool’. The diaphragm has to have be slightly convex on the displacer side, they also need one or more annular grooves in them to allow for them to flex.

I realised that the way to make the diaphragm for the TMG (Harwell engine) was to ‘spin it’. Ok I have only used the technique metal spinning once or twice before, but each time it worked.

How You ask?

Ok I would fix a nice lump of hard-ish wood to the face plate and turn a shallow concavity in to it about 1-2 mm deep with however many annular grooves I needed. This would be the ‘pattern/mould’. I would then make a ‘presser’ block for the tailstock which was convex . it would have to be smaller than the smallest annular grooves I would take a square bit of annealed sheer big enough to get the diaphragm out of with holes drilled in the corners and its centre marked. Centre up the sheet over the pattern and using the holes screw it to the back board. With the whole thing spinning, I would then slowly push in the ‘presser’ block nice and tight. I would make a tool from a bit of bar which had a polished ball end. With the lathe still spinning I would form the grooves by pushing it into the annular groves in the pattern. The correct lubricant to use is Russian Tallow but with such shallow spinning I think you could get away with a bit of pork fat.

When you have finished you could trepan it to size,

I know that my method is the other way round to that described in Wikipedia but we are only doing a very shallow forming. Our requirements are far less rigorous and our ‘draw is far smaller than the one shown here.

Good luck and regards


I just was not thinking properly

Thread: Is it Just me?
14/04/2012 12:57:33

Jim I am E-mailing you about Kandelos. The domestic form is all made out of Ceramic Tiles etc but my industrial version was made with a thin sheet steel wrapper. When I sold the shed it was in the man gave me a dead pig for the little Kandelo. These are 'multi fuel' heat extractors and storage heaters. My industrial type burned anything from wood through sawdust to household garbage mixture. It had an adaptor to burn dirty motor oil I got from a garage.



Thread: Arrange drill bits
14/04/2012 10:55:30

For my metric drills I use a lump of hard wood (NOT oak) and use the drills to drills a hole in it. I then write the drill size next to the hole. I have pukka stands for my fractional, number and letter drills. Dad bought them at the closing down of ole Noah's ship yard.



Thread: Is it Just me?
10/04/2012 18:28:25

Jim you know what that tackle is like. The Hazi (home brew moonshine is 100 times worse) I will not use it until it is at least -15C.

When it was -8C at night and -5C at Noon that was chilly now it is as now 18C in the day and -2C at night it is warm and soon it will be 15C at night and 28-30C during the day I get eye strain as all the lassies are bouncing about independently. I will stick to the 'Sor'

By the way how do we cope with -20C. I use a Kandelo they are easy to build -when you know the trick(s). The last one i built was in an old 50 gallon kreosote drum.

If any one wants to know how i did it i will write it up - your workshop can become an all year round business.



Thread: A useful Stirling engine.
10/04/2012 11:59:29

Ian The diaphragm forming is easy. What you need is a set of ‘Jennies’ and the necessary ‘formers’. If you look in MEW no 188 Dave Fenner has written up an article on making a set. You would need to make the bead rollers (dies for making fold up edges) which he illustrates in the article. You might also need to make a set of cutting rollers unless you use a bottom out of a tin for the job. Do not forget that tins are made of high quality steel. I have just had a look at a tin of ‘Dogo-Knosh’ which is about 3 ½ - 4“ diameter and it would be OK for the job.

You will have to make a modification to Dave’s machine by adding a bar attachment below the lower roller housing sticking forward of the rollers to give you a centre for your disk to run round.



Thread: Any ideas how to repair broken leadscrew
09/04/2012 12:41:27

The break seems to be in the part where the handle fits. The bearing looks as if it is on the main part of the shaft.

If the bit of steel you had welded on then you will be able to machine it to size.

The thing is it is a lead screw its major element for precision is that it has little or no back lash.

If it is set up carefully a butt welder can position within the tolerance allowed by my Chinese inspector friend Wun Thou Wong. The butt welded area would need to be ground down.



Thread: Is it Just me?
09/04/2012 08:17:06

There I was working away and all around me was misery, darkness and gloom. Cheer up I said to myself things could be worse. So I did and sure enough things got worse.


Thread: Any ideas how to repair broken leadscrew
09/04/2012 05:01:36

Know any one who has an electric butt welder?

If so try them you could get the two bits butt welded fairly accurately



Thread: A useful Stirling engine.
07/04/2012 12:59:15

Lyric Many thanks I still have a bit of Beryllium Copper left . I am now getting queer looks from shopkeepers measuring stainless food containers.



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