Staying a 71/4 boiler

[daveburrage]

Back to building a belpaire boiler after a couple of relatively simple marine types. A fairly hefty 7 1/4 gauge one as well. Last belpaire type I built was in the days of threaded and soft soldered stays.

Just drilling the boiler for stays - so getting near the scary silver soldering bit. Any thoughts on methods of soldering them in? All in one go (all faces inside & out) as per Alex Farmer? One side at a time? I spoke to a professional boilermaker who said he wrapped a ring of solder under the rivet head then heated the the area untill he saw the head drop. I thought it a good idea untill I realised it meant doing every face separately. What's the best way to apply the heat and feed in the solder?.I've got the use of propane and oxy acelylene.

regards

Dave Burrage

[Shawki Shlemon]

This is an interesting question , there is no wright or wrong method , its a matter of personal choice and available equipment , I can only say what I do .
1- completely finish forming /drilling all holes I assemble barrel / dome bush and outer wrapper using few rivets and silver solder /check and fix if necessary .
2- Assemble inner wrapper , front fire box plate and tubes , silver solder /check and fix
3- assemble the two parts together using screws / spacers and nuts in strategic areas , fit stays / bushes and silver solder one side , clean / inspect and fix , remove screws progressively as stays hold the boiler together .
4- repeat the other side /throat plate and crown .
5- fit and silver solder the fire box rear plate and fire door ring ,silver solder /clean and fix .
6- fit tube plate and bushes ,silver solder /clean and fix .
7- fit back plate and bushes , silver solder /clean /fix .
8- fit and silver solder foundation .
NOTE -
Every boiler is different and variations are needed . I believe doing it in a few steps ( I do 8 ) and ensuring each step is done properly saves time as no or a few repairs will be needed after completion .I hope this helps .

[daveburrage]

Hi Shawki

How do you heat the stays and feed in the solder?

Do you do any hole chamfering?

regards

Dave Burrage

[Shawki Shlemon]

Hi Dave
I use hard drawn copper rod for stays , I form one end so that will not fall in the hole .
I use oxy acetylene , first I warm the boiler and heat the area where the stays are using large multi hole tip and then I use no 30 tip with soft flame heat around each stay and when flux flow like water direct heat on the stay and apply solder . one can use ring of solder as mentioned somewhere on this forum but I have been doing what i said and build a few boilers like that , it works for me . I hope this helps .