Road Loco - 'Blackbeard'

Well, it had to be done so the Blackbeard team got on with stripping the cylinder down and removing everything connected to it, bagged it and labelled each bag. I am glad I kept lots of the sealable bags now. It was a sad day when everything finally came off.

BEFORE & AFTER



It is interesting to note where all the foliac goes when you pull the cylinder block down with the nuts, I had quite a bit of foliac get in the regulator chamber and into the steam chest areas when I lit up for the first couple of times and seeing the block off just shows you how much is squeezed over the boiler holes from fitting it. So when you are fitting one for the first time, when you apply it liberally (as described) I would suggest leaving around 10-15mm around the edge of the hole in the gasket free of foliac because it will get there eventually. It is sticky and will certainly affect your regulator.




Even before removing the block it was obvious what was causing steam to leak into the exhaust passages, a hole between the vertical tunnel that goes from the boiler surface to the regulator chamber and the exhaust port exit into the blast pipe.



Right hand picture here is looking up the steam passage from the boiler mounting face.



On a positive note the studs came out of the block relatively easily if a little time consuming, I used two 8mm half-nuts and was able to lock them together on all but 4 studs, these I used a pair of pliers to start them off and did not do much damage to the threads at all so all are resusable as they were cut to length already and did not fancy cutting another set down. and there is plenty of oil getting into the cylinder bores so the lubricator is working well.



Pistons took some getting out though, I could not unscrew the piston rods form the crossheads as the nut holding the piston to the piston rod came undone first. I tried to lightly hold the piston rod to unscrew the crosshead but could not get enough grip. As the piston also seemd to be unscrewing from the piston rod easily I decided to do that but as the end of the thread on the piston rod dissapeared into the piston it went tight so I had to decide if I risk damge to the piston rod or the piston - I choose the piston. Using a flat screwdriver I tried to hold the piston with the tip of the screwdriver after tapping a notch into the piston but it would not have it so I ended up tapping the piston round to unscrew it from the piston rod. It was either damage the piston or the piston rod. I think the pistons will be fine after I take the burrs off.

As a design update I would suggest STW drill two shallow holes or mill two slots in the front face of the pistons to allow a tool to be made with two prongs similar to that which unlocks an angle grinder nut. This would allow easier removal if needed in the future.

bjwlancashire wrote:
As a design update I would suggest STW drill two shallow holes or mill two slots in the front face of the pistons to allow a tool to be made with two prongs similar to that which unlocks an angle grinder nut. This would allow easier removal if needed in the future.

I always make my pistons like that now. I used to have a lot of problems with my Hunslet shearing taper pins in the crosshead and slowly unscrewing the rod. After a couple of times struggling like you, they got modified!

What a very distressing post to read on one hand but also reassuring to see that even the most horrible of issues can be dealt with relatively quickly although I wouldnt want to have to do this job myself. Of course it goes without saying that I have a concern as to how thin this area is and if there is a possiblilty that it can fail in time??? It would be good for Steve to have a look and post something regarding the cause. Hopefully it will be a reasonably easy replacement and you will be running soon. I look forward to the video.

Brian, I can only concur what Kev and Brian M have said, it is a very sad post and one of great concern. I agree with Kev, if Dean, Steve or anyone from STW looks at this thread I suggest that a response from them on this matter is posted or even a letter issued. I know castings can have large tolerances to take into account the casting process, but I thought an error like this would have come through on the quality inspection prior to being sent. It looks like a casting issue not a blow hole or machining error. It would be interesting also for STW to issue the findings of the investigation on how it ended up with a customer to give us additional reassurance.

Brian don't take this the wrong way but I hope you are the only one out there in STW land with this problem.

Look forward to steaming with you in May (milestone for you to hit i.e. Grey Hounds Gathering alternative venue)

Best regards,

Dwain

Flasback wrote:Look forward to steaming with you in May (milestone for you to hit i.e. Grey Hounds Gathering alternative venue)

Best regards,

Dwain

Dwain

Whatever venue you end up with I WILL be there!!!!!! You should have guessed my frame of mind by now, my glass is alway half full (especially when its my round)

Thanks for the kind thoughts guys, it is worth posting this information even if only for the information regarding how the foliac ends up under the cylinder.

BTW Sonic45 cheered me up no end this morning with some amazing photos of the belly tank paint work, it is like a mirror - a real credit to him and I owe him big time.

Cheers

Brian

PS: I am going to download the AMTEC application form and send it to Clive for approval, I may as well join the crazy gang.

Tank looks good, was thinking how Nick's engine was coming along and then I see his face in a belly tank...

Anyway good news to hear about the application form, this weekend is crazy as we have 3 STW engines at my house going through the professional hydraulic test and then a steam; 1 SL and 2 SM. We discussed Clive and Phil bringing their engines down as well but 5 engines in my driveway was not something my wife was over joyed about for some reason!!!!

I will try and do a few pictures as 3 STW DCC engines is a rare thing at the moment and will be good to see.

As this will be our 1st steam I am sure joy will be had and a few tears as well.

Keep smiling

Dwain

Dwain

Good luck to you all at the weekend and as you mentioned, please put some pictures on here. Did you get your roof bits yet? Lynn is already posting pictures of hers.

Brian

Brian,

Quick question did you pressure test your engine at any point before you streamed it?

Also how did the blow down valve operate, did it operate with a continuous flow of water when opened or was it a bit like a air trapped somewhere in the system?

Just looking at your photos and thinking about it

Dwain

No pressure test, just boiled water with the first go without the safeties on, second time low pressure, only went up to 80psi, third steaming blowing off. You will find most leaks before you make pressure or with lower pressures. As long as you raise steam slowly you can look around all the places it can leak while you are doing it. I do not have the facility to do a hydraulic test at home. If I can have the engine blowing off without leaks then the likely hood of a leak when we go 50% higher in a hydarauilic test is pretty remote according to my boiler tester.

Your blow down valve should do as it's name suggests, it will blow out steam and water with the lowest of pressures. Your description sound like you opened it without pressure in the boiler, just cold water. In this case, unless you open the injector valve or another valve to allow air into the bolier then it will only drip as air is trying to get in the boliler through the same opening the water is leaving. The same reason the belly tank has breather pipes, to let the air in and out as the water level rises and falls when you fill it or when you use it in the injector or pump. Open your injectore valve, blower valve and water lifter valve and see the difference. It is a good idea to warm your engine this way too as the water expands as it warms up. Leave your injector vlave wide open so that the air is let out of the injector overflow and once the water is about to boil you will get a tell tale sign.

Cheers

Brian

Cheers Brian,

Yesterday we were going through a pre hydraulic test therefore only cold water in the boiler. A number of issues need to be resolved before the steam ticket can be obtained. A few leaks, I think the whistle needs resitting or is faulty as water came out of the whistle with very little hydraulic pressure being applied. Plus a globe valve is not working (and yes it was fitted the right way ). What does concern me is the priming valve that comes out of the cylinder block. On the RL you are okay, but on the SM there is very little room between the cylinder and the generator bracket. Too little in my option (unless you have the hand size of a five year old), this valve should be the other side of the bracket. I think what we have on the SM is dangerous and will cause a few burnt hands this season. A call to STW I think on this issue as a modification is required. So a number of fires is required over the next few weeks to get ready for the steam ticket and commercial hydraulic day in March.

I have steamed my SRL a number of times with the exiter platform attached. I managed the blower valve easily with thick gloves on with no problem. You are not at the valve all the time so I don't see it as a problem.

I agree with Lynn. The blower valve is always hot because of what it is attached to, so you need to wear gloves anyway. Having said that, I moved mine as part of the new plumbing for the kettle.

Tim

If you open the blower valve instead of the injector when you raise steam not only will you allow the expanding air to exit the boiler you will also hear when you start to boil and assist the fire gradually as the steam begins to build up. You should blow down after each session in the early days to clear all the crap out of the boiler but only when there is less than 20 psi on the clock as it can be a bit of a shock to the boiler if you are high pressure.

Interesting what you (Brian) said about not trying a hydraulic before the steam test and also that your tester says 1.5 times the safety. My test was 2 times for half an hour which I did before I steamed so consequently had I got a weak patch in the exhaust I expect it would have blown through then. I was considering this the other night and put my mind at rest.

I'm actaully going for my second hot steam test in two weeks as I am a member of a club whose membership pays for a ticket each year so it will cover me for the whole season without worry in mid June, plus I will actually get around to sending them off to Walker Midgley to get my NTET disc this year.

Hi Kev

As I said I did not have the facility to do my own hydraulic test and as the boiler is already tested to 1.5 times working pressure, the legal requirement I decided to go ahead as described. There was steam bubbling up the chimney on the first steaming without making pressure but until I sealed all the openings for the second session could not be sure. Also, I had filled the boiler to the top and into the cylinder block to be sure nothing leaked. This I thought had caused water to be in the blastpipe, not a hole.

Interesting that yours was tested to 2x working pressure, I would expect that for a copper boiler but not a steel one and STW only test to 1.5x pressure. The full size engines also only go to 1.5x working pressure. Was yours tested by a Model Engineering society in the Southern Federation?

Brian

Yes it was tested by Chichester and District ME. As I have previously highlighted last year when working up to my initial test there was discussion as to what was required etc and there is a lot of differing opinions not taking into account the personal opinion of the tester himself. I was under the impression from an recognised ME that it was 1.5 times and the first test was valid for four years. This is not the case for my test as it was 2 times and valid for two years. I know that full size independant boiler testers will do a 10 year ticket, which for a brand new engine is a good idea so that's what I will do next year with The Coleman to keep costs down too. After that I would be happier with a two year local test as a lot will happen to the boiler in the second ten year time gap.

The other club I am involved with is put together specifically to get a boiler test each year in March which is who will do the hot test next week but again they only give a two year ticket for the cold. At the end of the day I have a ticket which Walker Midgley were happy with and it wasn't an issue and cost nil so all's good.

I was under the impression new steel boilers were valid for 4 years at first test, then 2 subsequently. First test at 2x, which would be done by STW, then retest at 1.5x.... I'd better go read my notes again then....

My boiler plate shows a working pressure of 14.7 bar with a test pressure of 24.5 bar which s abit over 1.5 times working pressure. But I have not started to look at getting any tests.

Ian

I really feel for Brian having this problem with his cylinder block. I know from personal experience just how disheartening and frustrating it can be. The cylinder on my chain track is a mark II.

This is the second failure we’ve had following field trials and they’ve both suffered problems in the same area. That is, between the exhaust and main steam inlet cores. I had chance to have a good look at the first failure and surprisingly the material thickness between the two cores was quite thick. There was also no indication that any of the cores had broken during casting. I’ve raised the issue with the foundry but even they have not been able to offer an explanation.

We give every cylinder a thorough examination before we start machining it as there’s over ten hours of machining in every block, let a lone the set up time. Included in this examination is an extensive prodding and poking around every core primarily to dislodge any remaining core sand. Both failures are quite visible now. I’m sure we would have seen this on our inspection, or at least we should have done. All I can conclude is that there may have been some crud present that obscured the fault from view. Perhaps the steaming/pressure dislodged it? To be honest though, I wouldn’t have predicted any problems in this area of the block, I expected them to be at the other end which is the highest point when they’re cast.

Without trying to diminish the impact on Brian personally, to some extent these sorts of problems are to be expected. With some 29 cores in each block it represents a very complicated casting indeed. That’s partly why we cut the first few casting up and why we pressure impregnate each casting after they’re machined. We initially investigated various forms of NDT such as ultrasound and x-ray but neither of these processes seemed particularly helpful because of the cylinders internal construction. They were very expensive as well.

For future production, we’re going to pressure test the main steam passage to the regulator chamber. This may not eliminate all potential internal problems but it would have found the problem in both Brian’s and the previous case.

Finally, I just want to comment on Brian’s observations on the use of Foliac. DON’T SKRIMP ON IT, particularly on the boiler to cylinder jointing. I would rather deal any mess it creates rather than have to take the block off because of inadequate application. Again I speak from personal experience.

Regards

Steve

I know from experience with some of the casting we have its not easy to tell. We've had a number where blowholes have appeared in oil ways and they're then scrap. We loose a lot more than 10 hours on them then, and its money we don't get back from the foundry. I'd say you've done all you can to try and prevent it.

I fully understand the casting process and the potential problems that can occur. I do not blame STW in any way, I was just unlucky. I hear the new castings are in so hopefully not long to go now before I am smearing foliac on again.

Brian

I have been getting on with a couple of little jobs that needed finishing plus I laid the planks on the roof and spent over 4 hours sanding it smooth in the cold last Sunday - notice my cutout for driving. I do intend to look at the extended regulator as I discussed with Tim and once the roof is done I will modify the seat frame to make it hang all the way across into the corners and then work out the appropriate bracket and lever for the regulator.

Hope to get the fabric on the roof tonight and get some primer on the wood....

Nice job Brian, I just love the way it changes these engines when the roof goes on
Hopefully you'll be able to run your engine safely with all the mods you're doing, without taking the roof off as Kev (Highpressure) is doing.... be interesting to see how you get on, (keep the pics coming!!) as I'm determined to be able to use the Showmans with it's roof in place on the highway!!

Regards,
Tony

Thanks Tony

Thats why I want to keep it on, it looks a beast. I think it will be painted white now although I had thought about satin or matt black. Underneath may be varnished but the the cross braces are only made from plywood and the edges show this - plus they are burnt from the cutting process. Otherwise, it might be grey.

The regulator extension is a realtively easy thing to do once the seat frame is on and easy to make removable. The main thing is the fact that an extension rod will run over the top of the coal bunker so some thought will have to be given to how to fire on the go and getting the coal in without the roof on can be challenging - maybe a chute would work.

When Tim and I were discussing this he was thinking of taking a new rod from the end of the regulator rod near the cylinder and running it up high at the rear of the canopy to enable you to still be able reach between the rear canopy supports on the showmans engine, the road loco has the cross braces so firing would have to be done by reaching around. A sharper bend on the shovel may help as the angle of attack currently means it slopes forward quite a lot and the coal falls off if your not careful, even just stood by the engine with the roof off.

Brian

PS: Hope to see Brian Morgan's engine at the Manchester show this weekend, looking forward to that.

A bit more roofing done on the first weekend in March, sorry it took so long to post the latest pics but work has been incredibly busy for the last three weeks so time is short.

A liberal application of PVA as used for sealing various materials.


Calico pulled tight and laid ontop (after my wife kindly ironed it after doing my shirts for the following week's business trips).




Edges wrapped after adding yet more PVA


Two good coats of primer. Need to curve and trim to length the rain beading, prime it and fit it before starting to paint the roof black.

Brian

Looking very good, I note you are planning on painting the roof black, this will get very hot in the sunshine,( well it may this year) it will make the beer warm. On a friends narrow boat he repainted his boat roof cream prior to that it as dark green and it was too hot to touch on a sunny day, now you can lean on it without burning your arm.

Ian