Vertical Boiler Fittings

That's the rebranded Folic which I have used but not tried the new one which is a combination of the two old Graphite and maganese Foliacs, one of which set hard the other did not. It was usually used for flat (flange) type fittings rather than screwed.

Greetings, I have been using loctite 572 for many years, with excellent results.

regards

Brian

Thank you once again Jason. Might avoid that one then.

Brian - Thank you. I'm quite tempted by Loctite 572. It's cheaper than 5770 and available in the UK. I'm assuming that as you have been happy with it, it must be ok at boiler temperatures. Would you be so kind as to let me know your thoughts on the question of whether it sets soft enough so that fittings will unscrew if required rather than snap off?

Edited By gary.a.ayres on 10/08/2018 08:35:40

Edited By gary.a.ayres on 10/08/2018 08:37:08

Gary

Just get the data sheets and compare them

Loctite 5770

**LINK**

Loctite 572

**LINK**

Loctite 567

**LINK**

Permatex 59214

**LINK**

Rocol steamseal

**LINK**

Pete

Edited By Doubletop on 10/08/2018 09:47:46

Thanks Pete -


I gleaned this from the data sheets:

Loctite 5770: After 24 hours @ 25 °C Breakloose Torque, ISO 10964, Pre-torqued to 5 N·m: 3/8 x 16 steel nuts and bolts (grade 5) (degreased) N·m 9.0 to 28.4LMS (lb.in.) (79.6 to 251)
---------

Loctite 572: After 24 hours @ 22 °C Breakaway Torque, ISO 10964: M10 steel nuts and bolts N·m 7 (lb.in.) (60)

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ROCOL STEAMSEAL is a high pressure, setting pipe sealant for metallic threaded and flanged joints.

Joints sealed with ROCOL STEAMSEAL are easy to break and clean.

--------

I find this kind of info difficult to interpret, and it seems to me that one can't make a like-for-like comparison between the two Loctites as the parameters are different. However, it *looks* to me that the 572 might be easier to loosen. However, the info that Steamseal is suitable for threaded joints led me in that direction insteaad, so I rang Heritage Steam Supplies in the UK who sell it. They put me on to their tech guy (involved with steam engines all of his life, steam cars and so on) and he advised me against the Steamseal as - he said - it does in fact set pretty hard (because of the manganese in it I think). In fact, he said 'just use PTFE tape - it will work perfectly well'. He was not at all convinced that there is a risk that shreds of PTFE will clog valves and so on.

He did, however, go on to say that if I want to use a sealant, use Wellseal, which does not set hard and is easy to dismantle if required. It can be used as a standalone or in combination with PTFE tape. 'Don't get yourself involved with Loctite and all that stuff', he said.

As a rookie I expected this to be simple but as usual it's tortuous and complex territory, and people have many different opinions. Interesting stuff!

So... given that in the end one has to make a choice, I have ordered a tube of Wellseal. Am not sure about the PTFE tape at this stage - have used it for hydro testing but for steam I might try the Wellseal on its own.

Feel free to comment further, but in any case thanks for all of your input on this.

Will report back in due course

gary

Hi -

Tried out the Wellseal this evening on a few fittings.

It's transparent, dark brown, runny and very sticky and looks for all the world like something chocolatey which you might squeeze on to an ice cream from a plastic bottle. You clean any grease from the mating threads (I used acetone), then anoint them with the Wellseal. You then leave them apart for about 5 minutes while the Wellseal thickens up, after which you either add a bit more Wellseal (if required) or just screw them together. Apparently it never really sets, so it's easy to remove the fittings if required and clean it off with a solvent.

I must admit that the stuff inspires confidence - it's so damn sticky!  It gets right into the threads and it's hard to imagine it not making an effective seal. However, the proof of the pudding will be in the testing so I'll let you know how that goes. If it doesn't work I'll try one of the Loctites which you guys have recommended, but for now I remain hopeful.

gary

Edited By gary.a.ayres on 14/08/2018 22:59:40

Edited By gary.a.ayres on 14/08/2018 23:00:46

There's always Boss White for the impecunious.

Neil

sounds like 'Harwich for the continent, Frinton for the incontinent'

Edited By duncan webster on 15/08/2018 21:30:58

I use Wellseal on my Motorcycle all the time. It's really good stuff for getting a good seal on mating surfaces. It doesn't harden and can be cleaned off with methylated spirits.

Thanks guys.

Neil - I hadn't heard of Boss White but it looks reasonable to me. I guess the Wellseal would be more forgiving visually if it oozes on to the copper, but it can all be cleaned off anyway .

I note that both Wellseal and Boss White have a top working temperature of 200 degrees C. Could this be a problem? I wonder if parts of the boiler - even those not directly touched by direct heat - might get hotter than that and ruin the thread seals. Remember I'm a clueless beginner...even if I do have good teachers .

There's always teflon thread tape too. It's so much less messy than gorilla snot..

Edited By Hopper on 16/08/2018 09:33:48

Boss white was LBSC's choice

It's intended for steam up to 7 bar, so as long as your steam pressure is comfortably lower than that (165 degrees for wet steam at 7 bar/100psi) yopu shoudl be OK. Don't use it for radian superheaters!

Neil

Many thanks, both.

@ Hopper - you are not the first person that has recommended PTFE tape. I have used it on the input end of my clacks as I was worried that any stray Wellseal might work mischief with the nitrile balls in the valves. I wouldn't rule out using it more in the future, especially in situations where cosmetic concerns are not paramount. ('Gorilla snot...' lol).

@ Neil - that's reassuring. My safety valve will blow off at 45psi. Will keep on trucking with the Wellseal now (also good for 200C) and see how it goes but will bear Boss White in mind for the future. It comes well recommended .

Cheers,

gary

Edited By gary.a.ayres on 16/08/2018 12:35:57

Progress has been slow due to hot weather (barbie season) followed by a major renovation of our living room which is currently ongoing. However, I took today off and spent some time in the workshop.

Stan Braye (on whose design this boiler is based) has little to say about he configuration of the cap, smoke stack and steam stop and safety valves, so I found myself having to figure it out myself. It was necessary to make extensions for the bushes on the top of the boiler so that the valves will sit above the cap. The first picture below shows the internal thread on one of them being tapped in round bronze bar in the lathe using a piloted spindle (which is a godsend - no more squint threads!):

I figured it would be easier to gauge the required heights for the extensions if I made the cap first. The photo below shows that the underside of the brass cap has a circular locating groove into which the top edge of the boiler fits. This was milled on my Dore Westbury Mk I using a rotary table. This is not the tidiest piece of milling in the world - a result of several issues which currently beset the mill (a situation which will be addressed in the near future...). It's not critical though as it won't be seen. You will also notice that the groove is a bit on the wide side - it's the size of the smallest endmill I currently have. Below you will see the cap (in which the hole for the smoike stack has not yet been made), the bush extensions, the cap retaining nuts (made from brass hex bar tapped M12), and the two valves:

The last photo shows a trial fit of the unfinished cap assembly. Unfortunately the two valves are out of perpendicularity with the top of the boiler. This happened either at the end plate forming stage or while silver soldering. They look squint but there is nothing I can do about it now other than put the fiery flame on it again and that isn't going to happen. It's not perfect but it shouldn't affect the functionality and will be good enough given it's my first effort. It does however mean that there is a small gap between one side of each nut and the cap. To prevent combustion gases from escaping via that route I would like to close this using some kind of soft washer or gasket which would have to be heat-resistant. Any suggestions from you good people regarding what I should use for this would be welcome. In the photo you will also see that most of the fittings are now in situ. They are sealed (hopefully) with Wellseal. Not so far away now from the second hydro test at 1.5 wp...! The picture shows the boiler in its current state sitting on the belt sanding attachment of my beloved Coronet Major woodturning lathe/all bells and whistles wood machining workstation:

gary

Edited By gary.a.ayres on 02/09/2018 00:38:51

To answer my own question above -

I went to a local suppliers and found this:

It's carbon gasket material, rated at 500 degrees centigrade. I reckon that will do! The stuff is very expensive but he had an offcut which cost me a fiver. It's plain black on the other side, and surprisingly easy to work. I scribed it with dividers, cut it with scissors, drilled it, and cleaned up the edges as best I could on a small drum sander chucked in the drill press. All very easy. Here's the finished set:

Here are the top gaskets in situ:

And here's the one under the cap, viewed from below:

The gaps appear to be closed and I have no reason at this stage to think it won't do the job.

When I was cutting the bush extensions to height, I forgot to take into account the thickness of the gaskets. This turned out to be a blessing in disguise because rather than make new extensions I just skimmed the nuts down to size in the lathe, making them look slimmer and (imho) better.

gary

A little bit of progress this evening after a major episode of DIY in the house.

All fittings (apart from the safety valve and the steam pressure gauge) are now in situ for the second hydraulic test at 1.5 x working pressure:



Apologies for the somewhat fuzzy picture. I'll carry out the test at the weekend. The cap and chimney are not yet silver soldered together - the chimney is resting in a circular rebate which I cut around the central hole to approximately half the thickness of the cap. My idea is to give the silver solder somewhere to flow into. Any advice anyone can offer on how to silver solder brass without ruining it will be most welcome!

The photo below shows a close-up of the water level gauge. Fitting it was easier than I expected, though I won't get too cocky until I have seen it not leaking under pressure. I had to make a 1/4" to 5/16" adaptor for the top bush due to a mishap back when I was silver soldering the boiler. It seemed to work ok, but time will tell.



gary

Chimney silver soldered on to cap:

Second water pressure test at 1.5 x WP successful

All fittings were in situ apart from the steam pressure gauge and the safety valve.

On to the first steam test next, using gas to fire it with.

A major staging post achieved. First steam!

Edited By gary.a.ayres on 07/10/2018 20:19:54

Hi Gary,

Well done! I enjoyed your clip! Nice to see someone make their own boiler! And Jolly Good Fun too!

Cheers,

Julian