Member postings for Richard Parsons

Stub

I have many pictures and profile drawings of the RABA 48. It is a narrow gauge (750mm) of the MAV standard gauge shunter the RABA 24 (aka M43). Both are diesel hydraulic units with a two off four wheeled bogies. They are called ‘hydraulic’ actually they have a ‘Fluid Clutch’ Transmission system. There is a very good book by Paul Engelbert called ‘Forestry Railways In Hungary’. A 3 ½” gauge RABA 48 would be a powerful little passenger hauler

To Google try ‘Magyar mozdonyok’ or ‘Dízel mozdonyok’, at this lot ’lillafured narrow gauge railway’ There is a few good images here http://www.youtube.com/watch?v=jDz_FBDeykw, but much of it is ’arty-*arty’ stuff This one is the closure of the Kecskemet Bugos line http://www.youtube.com/watch?v=LbN-qyGhENY&feature=related

Want more I might get you some more data

Wotsit. Your stuff with the yellow flux coat is probably the same thing that I use. I used to use my Siverts for silver soldering. Over here I noticed the flux (Borax) residues were Black after an attempted at brazing and caused the pickle to have a black sludge in it. I came to the conclusion that Propane/Butane we get over here was dirty. I bought a ‘Flamefast’ gas/air torch from the U.K. –hence the Hoo-Har about the compressor. This burns at a much higher temperature and burns off the impurities –no more problems. I bought some flux over there called Stellar s.r.l Flux AG1. In use it does not foam up like hydrated Borax you buy from the chemist shop.

Can you tell me about thr Busses in Romania. In Hungary all citizens of the EU who are over 65 travel free on them. Is this the same in Romania?

David

That is about all.

Regards

Dick

Gordon I agree with you entirely.

I have 5 projects ‘stopped’ for lack of materials One is within for a 250 mm length of steel which I can only buy here in Hungary from Germany –reason zoning- in the UK, France etc I can get it from the U.K. The Germans require my VAT registration number the UK do not need it. I think the message has not gotten through.

Projects 2&3 are waiting for about 150mm of 3mm steel. I bought all my local supplier stock (5 meters) about 3 years ago. I went to the cashier and paid for it. I spotted the packing ‘Gorilla’ coiling it up for me when I yelled ‘NEM’ the (Hungarian for no) he took no notice and squeezing the end up and twisted it like a coiled bootlace. I chucked it on the floor and walked out. The Gorilla chased me with it shouting and brandishing it and a length of 50mm bar. I hopped on my scooter and lit out like a jack rabbit dogging through the gate before the Gate Goon could close it.

Project 4 is waiting for a bearing. The Hungarians have found the idea of ‘Minimum Order quantity and I can only buy a full pack of 50 of them.

Project 5 (to cast and build a ‘Box Plainer’is shelved for the same reason I can only buy 50 x 2 litre cans (These are packed in 4s). Work it out for yourself they have to ‘break bulk’.

I am now waiting for two more items of information before I start to cut metal, the crank shaft OD and the Cylinder max OD and length. This is for the 5cc CI engine in ME. I have the rest in a metal box locked and well hidden.

Copper Sulphate. Go to your garden supplier they sell it. It is main ingredient of 'Bordeaux Mixture' for your vines

Merry Miller, when I lived in the U.K. I used to poke around in the used tool shops, where I would often find odd (often part sets) of collets often ‘going for a song’. I made a gauge which allowed me to set the compound slide to a No 2 MT. Once you can do that easily you can make all the accurate collets holders you will ever want.

Rgds

Dick

I now have about enough information from your postings to refigure the transfer ports. Your suggestion of drilling them at an upward angle seems good but I will only do so in those regions of the cylinder which do not face an exhaust port. Those holes will be at Right Angles to the bore. This will direct the fresh gasses into the centre where of the cylinder the ‘pent headed’ piston directs gasses upward. The idea is to avoid losing too much of the fresh charge and getting rid of the spent gasses.

When I have lapped in the piston I want to hear a descent ‘pop’ when the transfer ports open. This means minimising the dead space in the crank case.

I am not going to throw teddy out of the pram but I have a touch of the ‘Grump’ again. The machining of the crankshaft is described but NO finished dimensions given (yet). I have to order a 7mm reamer from a local supplier. What else do I need?

Raymond In view of the scuffing you found and the fact that you are trying to reproduce an engine from the late 1940s early 50s I understand your design. I do not want to re create anything I am going to build a 5CC diesel based on your design.

My first change will be to use an oil seal (SOG 102711 8 22 7 2) outboard (on the propeller side) of the main 7mm race to maintain crankcase compression.

My second change will be to use a ring of holes (of a suitable size) as transfer ports.

Raymond would you (and anyone else) care to comment.

Andrew Hi

Lawrie

That is what we used in the 50s. Two things the bottom edge of both the knife and the back plate were bevelled to reduce thickness and give the Honey less to stick to and reduce the drip size. Under the head of the retaining nut (A wing nut) there was a fairly substantial spring. The thread used was of course was ‘O’ BA. (so if you lost it you could not go to the local Iron Monger and just buy a new one. Until Dad ‘Blew the Gaff’ and told old ‘’Tinny Clarke’ what it was.

The whole thing was made out of stainless steel and I think had been ‘liberated’ as it had the letters ‘DR’, a swastika and an eagle on it.

Clive Over here in Hungary it is common in the Boondocks to have stainless steel water pumps for drinking water. I will have a look at the 'Gazda bolt' (the sort of farm shop) and see what they have. I also remember that in the U.K. both caravans and boats used metal water pumps to lift water from the tanks into the sinks. Have a look around Boat Chandlers and Caravan suppliers and you might find what you want

Rdgs

Dick

John I was always taught that there were 4 taps in a ‘full’ set. As you write there are the ‘Taper, Second and Plug’, but there is also a ‘Bottomer’. All the three taps you describe all have a taper on them to a greater or lesser extent. Then ‘Bottomer’ has no taper at all. It is used to finish a blind hole and is quite rare.

Syd I will agree with you but the supply of a second in place of a taper is 99 times out of 100 down to the supplier. They do not know any better (nore do they care)

Andrew I am interested in getting sets of progressive/serial taps in the smaller BA sizes. After a few weeks using 12, 14, 16 BA, 8 BA seems like ‘heavy engineering’

Some of the taps I have are badly oversized which gives me problems (so I avoid those sizes).

Long ago and far away a certain number was dinged into my skull (I can still feel the bump there). The number is the speed for turning mild steel with High Speed/high carbon steel tools. In inches the RPM to use is 288/D where D is the diameter in inches of the billet you are machining. In metric it is 7315/Dmm, where Dmm is the diameter in millimetres.

These figures are guide lines. If you are machining a 1” bar and running at exactly 288 RPM you should increase the speed after every cut. If you are ‘facing’ something and think like that then you have big problems.

If you use the calculated RPM based on 288, and adjust your feed rate to get a suitable cut.

Remember not all lathes have infinitely variable speeds, but the magic number will give you a good feel for the speed to use. So the difference between 420 and 458 RPM is pure nit-picking. I would tend to use a speed around about 300 RPM for a 1" billet.

No two bits of steel are exactly the same even if they came from the same billet.

David I keep well clear of the Alps the Bacco-pipes there are huge. It would cost me a year’s Bacco rations to lend one of them lads a fill !

There is a saying “if you have a problem give it to the armatures. They will solve it”.

Stub The ‘Doodle Bug’ (V1) was guided in a way. My old man did a bit of agricultural engineering. In the late 40s and early 50s there were still German and Italian POWs in the UK. The old man was allocated two to help with the ‘humping and heaving’. One of them had been part of a ‘Doodle Bug’ launch crew. He decided to ‘stay behind’ when they were ordered to retreat. The V1 was guided by a magnetic steering gear which ‘tweaked’ the yaw gyro. Before launch the machine was placed on a wooden stand where it was turned round to orientate it and bopped with mallets to change its internal magnetic deviation. The Doodle Bug was nasty. It was small, difficult and dangerous to attack from the air as it had several hundred pounds of bang stuff inside it.

The point is that anyone with evil intent and the ability to use tools can do it, but the lower levels of security are suspicious and dim. And remember to them anything you make could be part of a weapon –even a 3 ½” flat truck.

Rdgs

Dick

Neil,

First of all I would use a very thin smear of engineer’s blue (not marking out blue) and do a trial fit to the lathe bed. If the fit is less than 85% get the Headstock base reground as well.

Second get a nice straight bar just pinch up the headstock and with a sensitive DTI check that the bar is parallel to the bed OK if not well think about the use of a scraper.

Torque the bolts up by hand slowly in a star pattern leaving about 15 minutes between each tightening for the stresses to come out. Use a thin smear of oil on the bed when you do it.

There are no values in my Super 7 hand book (am I allowed to mention this by the new owners?)
RGDS

Dick