Posted 15 March 2017 - 08:02 PM
I'm in the process of building an all in one vessel using a 56 litre pot with a 25 litre malt pipe and decided to treat myself to some stainless steel fittings. After getting a recommendation for a local supplier, I opted against sourcing the fittings from eBay.
I grabbed a box full of various 1/2" fittings from this local supplier, only to discover that the storeman gave me NPT nipples when all of the fittings are BSP, after I worked out the tees, elbows and ball valves would only take up half the nipples thread. Not too worry, called the supplier and got them swapped over for BSP thread today.
This is where the problem. The BSP nipples seems worse than the original nipples. The problem occurs when trying to fit these fittings to the large pot. The fittings will not tighten up against the wall of the pot, it feels like I'm going to pull the fittings through the wall of pot when I grab the fitted ball valve. I started to think that the walls of the pot were too thin, so I grabbed my brass fittings and they were simple to fit the very first go!
I'm confused and frustrated. Is my only option to return all of the fittings, and start again with the recommended eBay supplier? I'm seriously considering switching back to brass, although I'm keen to run stainless on the new setup.
Any help would be greatly appreciated.
Posted 15 March 2017 - 10:10 PM
Not sure what you mean by the fittings wanting to pull through the pot wall? Do you mean the threads are a loose fit inside each other? If so, sounds like the sizing is wrong. Pics of your setup might help in explaining the problem.
FWIW, although NPT and BSP thread pitches do differ, for the purpose of creating a low pressure connection on a homebrew setup, a roll of thread tape will solve your problem.
Posted 21 March 2017 - 01:12 PM
Thanks for the reply.
I was unaware that there were different types of BSP. I think I must have a mixed bag of BSPP and BSPT as some now fit whilst others are more problematic.
I managed to solve the problem by grabbing some weldless bulkheads.
Posted 21 March 2017 - 01:19 PM
Be aware that most of the fittings out there atm (well im my reach anyway) are pretty crap.
The threads are generally badly cut, and in alot of cases, will only screw in a couple of turns without... persuasion.
Have a good look at the threads before jumping to any conclusions.
Posted 21 March 2017 - 02:45 PM
I went the China/HK route for a couple of S/S fittings last year and got pretty average finishes on the threads while the actual fittings appeared fine.
One of them was even completely wrong, a keg connecting instead of a lump end, they switched that for free though.
I'd love to have a go at cutting my own threads but can't source the S/S material easily.