Coke for brazing purposes

In older copies of the magazines it was always mentioned to pack work being brazed well with coke before brazing with paraffin blowlamps. Even as recent as the earlier Don Young and Tubal Cain articles.

Is there any reason why this is not used today? (or is it?) as coke or breeze is still available and as a way to generally heat a workpiece together with more localised heating it seems like it could still be useful.

Is coke generally available? Last time I looked to buy some it was unobtainium in small quantities. (I did find a local coal merchant selling it by the ton.) Coke was common when domestic gas was made by baking coal but we all burn natural gas now. Now coke is specially made for steelworks etc and doesn't seem to be sold as ordinary fuel in bags. Or at least I couldn't find any!

Coke being porous and mostly carbon makes it a good insulator for hot work. Good stuff if you can find it. I'd look at Vermiculite instead, not because it's marvellous or cheap, but because it's available.

Dave

I suppose breeze blocks will soon be a thing of the past as one of the major ingredients was ash from coal fired power stations.

Mike

A benefit of using coke would be the extra heat generated by its combustion. This might be less useful now with the availability of poweful propane torches, compared with the fearsome 5 pint blowlamp of old.

More ash and alkalis, but charcoal might be a reasonable substitute these days, if you really want to go that route for brazing. Arrange to do your brazing after the BBQ?

Blacksmiths use Coke “beans”.

**LINK**

An alternative may be lumpwood charcoal?

Coalite is a brand named supply of coke, in fact any of the 'smokeless' bagged fuel on garage forecourts will be coke. Coke is used in steelmaking instead of coal after driving off the sulphur and hydrocarbons that would contaminate the steel. These are the same constituents that cause smoke, smog and smells that the use of smokeless fuels avoids in clean air zones.

It was used as an insulator primarily in boilermaking but with the sort of advantage of also burning. if there was enough draught. In the 'fifties before north sea gas made gas heating cheaper than coal probably 95% of model engineers had coal and coke at home already. Charcoal would not be very good as it would catch and burn too readily.

This is where I have seen it - close to me, but perhaps not to you.

LINK

Nick

Hello Nick,

Go down to your local builders merchants and buy some Thermalite blocks or equivalent. Very cheap, and can be cut up if required with an old wood saw.

The 5 pint paraffin blow lamp used by Don Young on the only 2 boilers he ever made is a fearsome beast! I doubt if Don did use coke as a surround for his 2 boilers. I used a 5 pint paraffin blow lamp on the first joints on my first miniature locomotive boiler until I bought my Sievert set (propane). The heat output from a 5 pint paraffin blow lamp is quite something.

You would not want raw coke igniting when silver soldering a boiler. You want clean joints and heat that is controlled where you want it to be.

You need to take some of what Don Young wrote with a pinch of salt (hefty doses in places)! Don's 5"g LNER K1/1 boiler was probably silver soldered up in the works of J Samuel White. Don's 5"g IW O2 "Fishbourne" boiler was probably done by him with the old 5 pint blow lamp, but the loco never had a steam up on a track when completed, and was sold in the late 1960s (to Canada) and has never been seen since. Neither boiler ever had a club boiler certificate.

Don's only other loco was his 5"g Railmotor No.1 and Alec Farmer of Reeves made the boiler for Don.

Cheers,

Julian