Member postings for Larry Coleman 1

Hey clogs

The old books I have will go to the power house museum. I commend you if you make sure their preserved.

My prize possession is the 1906 Babcock & Wilcox "Steam Its generation and use" It has some amazing charts on how to design smoke stacks from brick.

It also talks about boiler explosions which I will scan for you all to read.

Larry

Bill

What drove the line shafts, steam engine or diesel.

I find those old buildings fascinating. When I lived in Sydney my friend and I used to explore the old gas works which was steam driven and the steam engines were still in place. The old retorts were still in tact but it would have been a hell of a place to work.

I had to laugh, I was offered a diesel engine once for nothing and on investigation I found it was a 4 cylinder Ruston & Hornby. The only problem is it was about Twenty feet high and weighed 38 Ton. The alternator was ten feet in dia. What a pitty I didn't own a low loader and had some where to store it. It was a beautiful old engine still in running condition. Simsmetal got it for scrap.

Larry

Edited By Larry Coleman 1 on 11/01/2015 03:58:56

Yes your right bill.

WH&S has gone way past its purpose these days and high payed government employees use it to justify their salary.

Manufacturing in Australia has almost died and WH&S have a lot to be responsible for.

NASA has developed some miracle lubrications in the last ten years theres no need to kill animals for lard. But I am not ridiculing hunting as a hobby. I have participated in the ultimate hunt but the hunted was shooting back at me and on one occasion hit me. I think when you know what its like to be hunted you loose all enthusiasm with the sport.

Hey Andy if you turn your monitor around can you read the back of the page. And still have not told us what the machedy is for.

Larry

Thanks Ed

Someone told me to use sugar or molasis then bake it. After the casting just wash the sand with water.

What I am searching for is a method that does not require the purchase of expensive bonding agents.

Larry

I think we all may be missing the point here, Forget the oil, Has anyone thought we may have improved the way a surface finish is accomplished as well as the end result.

Now I do know if you want to remove oil of a surface Ultrasonic Vapour degreaser is the way using freon 13. The military eccept it. And a vapour degreaser cleans in pure fluid because it is condensed by the cooling ring.

Anyway a very interesting conversation.

Larry

The cylinder square

Now lets get on to cylinder squares.

Now from time to time you will have to check if your square is correct. So you put square on to another square and it shows an error so which one do you believe is right.

The best way is to make a cylinder square if you look at the picture basically its a cylinder but it must have two requirements.

The cylinder must be parallel within tenths.

The dia and the ends must be machined in one setting.

If both parameters are carried out it will stand perfectly square.

Simple and effective.

Larry

That is an excelent link and I liked the tree lathe. Thanks Ed !

I remember operating a lathe driven from a line shaft with flat leather belts. It was a WH&S nightmare but it worked well. On the fine cuts you jammed a bit of wood against the spindle to reduce the slop in the bronze bearing.

Larry

Yes I think your right they might be protected but you can buy bottles of it at most pharmacies. It is also used for rubbing into joint strains as a liniment.

So for those who don't hunt can you uses bacon fat or fat from pork roast.

What I actually meant was what part of the pig do you get it.

Larry

Edited By Larry Coleman 1 on 10/01/2015 08:12:28

Danny

That is interesting. Where does the lard come from and have you tried Goanna oil. Suprisingly it will penetrate glass.

Goanna oil is what is used in bleeding bolts. Where you have a pin in a crane that takes maximum loads they are prone to fine cracks. So they drill a hole in the centre removing the fulcrum point and fill it with Goanna oil and red die then weld the dye in. Now the dye will penatrate fine cracks and on inspection if you see red oil the bolt is cracked.

Larry

By the way lads I am venturing into casting brass parts and my knowledge of that is about one out of ten. I am building a smelter at home and I am in real Tiger country.

Can anyone tell me how to get the mold sand to set hard. I have been told to mix the sand with Molassas and bake it.

I also have a solid carbon crucable and I am wondering if it will work.

Can you make molds from plaster of paris? for alloy and brass only or will it explode.

Totally lost for knowledge.

Larry

As soon as I can I will describe what spotting screws are, but I will have to take some pictures of them first.

Have you ever tried to drill screw holes to line up with blind threads already drilled in a pattern by measuring and marking them on the new plate you are trying to replace.

Also we should mention what toolmakers buttons are, and I will take pic's of them later and explain there use.

Cylinder squares should also get a mention.

Larry

Yes Bill

As much as what I have said sounds strange it works and there must be other techniques out there we don't know.

Try the rag theory it does work ! You do not have to remove the front rake on the drill.

Larry

Now how to drill a one inch hole in sheet metal with a new drill and get it round.

I worked in a sheet metal shop for years and although we had a room full of presses and punches i was asked to drill a one inch hole in a sheet metal cabinet made from 16 gauge and the hole that existed was half an inch.

so I got the big slow speed hand drill and a one inch drill with the end machined down to fit the chuck. I quickly started to grind the drill cutting edge to a very sharp taper and I removed the forward rake to prevent grabbing. The head toolmaker came out and asked me what the hell are you doing. I explained what I was try to achieve. He took the drill and resharpened it back to the way it was and proceeded to the cabinet. He set the drill up in the chuck and then took a cotton rag from his back pocket then he ripped of a piece about four inches square and folded it twice. He then placed the drill on it and pressed the trigger. I stood back expecting all sorts of bangs & clunks but the drill went through with no chatter and drilled a reasonable round hole.

The rag practice was used quite often even in the lathe when you drilled out internal metal of a die after a pilot drill.

Caution:: If you drill sheet metal on a dill press do not hold it with your hand and make sure you clamp it securely.

Try it it works

Larry

Edited By Larry Coleman 1 on 10/01/2015 01:57:16

Edited By Larry Coleman 1 on 10/01/2015 02:45:53

Well many years ago I had a box of No 3 Morse taper drills.

My hobby lathe was No2 and so was my drill and an old fellow said to me why don't you turn them down. So I heated them up to a nice cherry red and packed them in lime to anneal them but they were still very hard to machine. I contacted him and asked him how to soften them.

He came over and heated up the taper part only to cherry red and left the drill in the vice. he took out his box of matches and rubbed a match down the taper and it went black. To hot yet he said. Then he did it again and again until the match went brown. He quickly dropped the drill into a tin of cold water.

When I placed the drill in the lathe chuck I then machined it with high speed steel very easy it was soft.

He explained to me that that was the temperature the metal crystals change state. Much to my surprise it worked and I have never forgotten the process.

To reharden it you heat it to cherry red and immediately drop it into a bath of cold oil and I use car sump oil. then temper to light blue.

Larry

Edited By Larry Coleman 1 on 10/01/2015 01:26:48

I have started this thread to try and document engineering knowledge forgotten over the years by evolution.

Things like how to soften the end of a morse taper drill ( water annealing )

How to drill a one inch hole in sheetmetal with a new drill.

Jason

I think we must accept we do not live in a perfect world. Don't forget the atmospheric humidity and as minute as it is it would condense on the surfaces. In the Metrology room the operator wears gloves and at times we donned the mouth mask made of cotton like a brain surgeon to prevent fogging up the surfaces. Now we really were splitting the atom in my opinion.

Now I think that none of us will ever use this type of equipment in model making and I have only seen a gold yard stick once in my life. I wonder if they still exist. It is interesting to wonder if engineering today is still advancing or has our diligence for perfection been lost...

It is exciting to talk to you guys and as a dinosaur of engineering development I have forgotten more than I have learned in the last ten years but I am still learning. I still wonder around the university labs here and build scientific equipment as a volunteer. And some of the Ph.D.'s look at me funny when I say, well lets build a device for that experiment. I built an X ray machine for them but the perils of being able to run it destroyed that unit. Government licenses & WH&S became to expensive.

Take a good look at the three D printer what is it? In fact its a 3D pantograph in reverse. In stead of removing the unwanted material and leaving the target reproduction. We only place the wanted material on the table.

I might start a new thread. Forgotten engineering techniques, Because it is our obligation to pass them on.

Theres a few topics to throw around.

Larry

All very interesting comments.

When working in the Met lab the slip gauges were used to check and calibrate Go & No go gauges for production purposes. Now what we are talking about here is a temperature controlled room where both the slips and the gauge being checked were placed in a ultrasonic vapor degreaser filled with freon 13 and then wiped clean with a disposable cloth. now if there was any oil left on either component after that it was so insignificant to even guess.

After use they were wiped with an oily rag to remove any human skin acid and placed back in the box for storage.

I agree with Andrew about his thoughts on Nitrogen getting between the blocks without an oil film but wring two of these blocks together and try pulling them apart, With master blocks you will not succeed.

Also optical flats which are used to check the blocks do not have any oil film on them and you have to ware special gloves to handle them. they are made of special optical glass or quarts crystal. place them on the surface being checked and switch on the sodium light and you will see black rings where there is any ware.

But to get to the point the amount of oil on the surface would be so insignificant it is really not worth talking about. Now don't forget temperature plays a big part and I dought if you will ever use or see gauge blocks outside a Met room.

Larry

Edited By Larry Coleman 1 on 09/01/2015 09:54:40

Gordon

I don't know much about foundry work but the men who told me about Rolls Royce burring engine blocks in the ground were the worlds most respected engineers and I heard it many times. Thats all I know and I would like to know what the hell it was supposed to do. The funny thing is that some of the old tradesman I worked with also knew about it but I never pursued the topic. I wish some of them were still alive so I could ask them.

One thing I did find out recently is all the engines on the Mitchell Bomber had solid pure silver bearings and I think the B25 did also.

Maybe its lost forever.

Larry

Pip

I might be showing my age here but I was trained by some of histories great men and in the field I worked in after I did my trade as toolmaker I worked in military weapons and if I knew 20% of what they new I would be doing well. When I worked at Hawkers I meet the man who designed the spitfire in WW2. My friend down the street was Bob Ford Frank Whittles assistant engineer when they developed the jet engine in the UK.

But I can understand your trade and believe it or not bricks and mortar do not get on to well with me because its a talent that requires a lot of skill and knowledge. I can not get on with wood work and you would think working in metal would help but every time me and wood clash its a disaster. Maybe its a passion for the trade that can not be explained.

I remember all those great men and they are my idles. Working in aircraft propellers is a black mystic art and it becomes instinct maybe that is why I used to get all the ships props to fit.

I love talking to people about engineering and believe it or not I do learn a lot from model engineers.

Larry