|not done it yet||19/10/2021 20:57:20|
|6430 forum posts|
In the late 1950s the rail siding at Finmere went up. About a million and one railway sleepers well alight. We could see it from (about 5-6 miles away as the crow flies) while milking the cows. When the milking was finished Dad piled us into the van and off we went to see what it was.
There were over thirty acetylene cylinders on site and half a dozen went off with big bangs. I can remember we were standing close enough to get quite a strong pressure wave. At least two went off while we were there (along with a large crowd of others, being warmed by the fire). A while later a copper brought us a pice of shrapnell which had landed on the road some distance away - further away than we were watching from! It was still hot when he showed us - he still needed leather gloves to hold it. It was about 9” long and as wide as his hand.
Soon after, another one went up and we could see the firemen taking cover - probably too late, but not for descending burning sleeper bits . We departed soon after, when we were told how many bottles were on site….
|David Caunt||19/10/2021 23:49:22|
77 forum posts
My Dad used to make his own Acetylene in the early 50's and when he cleaned out the dregs it all went down the manhole in our drive. It never occurred to anybody that it would be a problem. I can't imagine how one would dispose of it nowadays.
|John Olsen||20/10/2021 03:41:56|
|1215 forum posts|
The end product from making acetylene with calcium carbide is calcium hydroxide. This is pretty harmless stuff and occurs naturally anyway. It is used in food preparation (E526)
|not done it yet||20/10/2021 06:57:56|
|6430 forum posts|
Probably not used quite as much these days, but farmers spread lime on soils as a pH regulator. I used to (almost daily) have a chat with the lime kin operator, when collecting the daily sample for testing (around 1970). He had a very ruddy complexion which, at the time, I thought was likely due to his working environmrnt.
Production, back then, was by calcining high grade chalk with coal in a vertical gravity kiln/furnace and hydrating the resultant calcium oxide as it slowly traversed a (largish) screw with water sprayed on. I expect it is produced in gas-fired horizontal tube kilns with cyclone preheaters, these days. Powders, not lumps of chalk, in a ‘relatively’ dust-free environment these days compared to the method back in the middle of the last century.
Edited By not done it yet on 20/10/2021 06:58:54
|Keith Wyles||23/10/2021 12:22:31|
|76 forum posts|
This thread has got me wondering about the future. Will gas welding / brazing/ soldering become a thing of the past as we become greener and move away from gas? Will this have implications for our hobby?
|noel shelley||23/10/2021 13:28:50|
|847 forum posts|
Hi Keith,Many would consider the petrol blow lamp falling by the wayside as no bad thing, MIG welders were the peserve of the industrial user, now you can buy one with the groceries, or even buy the delux version with a TIG attachment. Induction heating is coming into the hobby market ! The only need for gas will be as a shield ! Is it progress or change ? Noel
|Keith Hale||23/10/2021 14:09:07|
329 forum posts
The demo by Helen at the Midlands exhibition was carried out using an oxy-propane kit from CuP Alloys not BOC
She did the work, I did the commentary.
|Tim Stevens||23/10/2021 14:54:32|
1490 forum posts
Actually the residue from Calcium Carbide - yes, its calcium hydroxide - is really excellent as an absorber of carbon dioxide. The result is limestone. So, taking that process alone must be good for the environment ...
But of course, the science must be looked at in the round, not in isolation. Carbide is made by heating lime with coke, and the lime is made by heating limestone - giving off carbon dioxide. Yes, exactly as much as will be absorbed in the carbide residues.
The big problem with model boilers is that they are made from copper, and so draw the heat away very quickly. And it is difficult to hold the bits firm while surrounding them with insulation.
|Keith Wyles||23/10/2021 18:35:16|
|76 forum posts|
Years ago, when I regularly used acetylene and arc welding, i remember trying to use carbon rods to provide heat. I never really mastered the technique of holding the rod tips at the correct distance, but didn't try it for long.
|Bill Dawes||29/10/2021 20:12:06|
|493 forum posts|
Hi Peter, sorry a bit late in the day but I bought an Oxy Turbo 200 kit a few months ago, was getting extremely frustrated at all the heat I was having to put in to my 5" boiler to repair a few weeps. I did it but jury still out to be honest, I put some background heat in with my Sievert propane torch and finished local area with the Oxy Turbo. A first timer with it so quickly used up the oxygen cylinder getting the flame right, not used it since but I need to have a bit more practice, Small O2 cylinders expensive unles you are good at it and its a quick in and out.
A friend of mine uses oxy acetylene but he is a qualified welding engineer as well as a good welder.
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