BOXHILL by Martin Evans

[Cro]

You are correct in its function but I disagree in your "worst case scenario" as the safety valves are not being fully tested against a constant raging fire. If you are to shut the blower off completely at that point the draft is gone and although the fire will still be burning bright it will die down to a stable level fairly quickly whereas keeping the blower on keeps the fire at this level therefore testing the safety valves to ensure that the pressure cannot "accumulate" too much and that they operate in a safe manor and release enough pressure to stop the boiler reaching dangerous levels.

I think you'll find in a lot of cases we never reach "optimum heat generation" before we meet max working pressure so we are not wasting steam by having the blower on at this time as you suggest, obviously we are using some yes but not more than we are generating.

This is the way I have always understood it to be and to me seems logical that you are testing against a potentially dangerous case, I have seen in the past owners walk away from a loco with a blower on hard and it gets to full pressure and its going crazy with no one watching it, if we didn't test in that scenario how would we know it will be safe if this were to occur?

Adam

[Cro]

I had a bit of time at the Bluebell yesterday crawling over both the rotting 9f and the beautiful BR Std 5 Camelot 73082 to get some dimensions for the pedestal.

Anyway whilst I was there I thought I'd make the most of being on the shed and get some photos of Stepney for you Julian as I doubt it's often you get to see it and the photos the better.



The album has the rest of the photos.
Adam

[jma1009]

Thank you very much for the above pic Adam, and very thoughtful of you.

How do I access your album?

If you potter over to the Bluebell again do let me know and I have a few details I wouldnt mind close up pics of!

I am afraid my own Stepney hasnt been touched since June. My very old dear friend John Salter of the IWMES is holidaying here for a few days this week, and no doubt he will have a go at me for lack of progress! He is booked into a guided tour of the Royal Mint at Llantrisant as a 75th birthday present this Wednesday.

Cheers,
Julian

[Cro]

Julian,

If you click on the photo it should take you to the photobucket page and the album is labelled Stepney.

I may pop along at the weekend as it is their Giants of Steam Gala but undecided at the moment.

Hope they are of some use,

Adam

[jma1009]

Hi Adam,

Many thanks for the above and the pics are excellent.

Cheers,
Julian

[danlank]

Hi Julian, have found this thread fascinating - read it twice through in the hope that I'll get round to building a Terrier one day. Just wondering if you've made any more progress since? Would love to see how Stepney is getting on...

[jma1009]

Hi Dan,

That is very kind of you and glad found my thread of interest.

I am afraid Stepney has been gathering dust for 12 months, and apart from the blower ring September last year has been gathering dust for quite a few months previously.

I had to sell my 5"g GWR 0-6-0 loco June 2016, and since then I have found it very difficult to get motivated to do anything much in the workshop.

It is all rather silly really as in general terms Stepney requires very little apart from painting to be finished and in steam (and I have always enjoyed painting miniature locos).

I am sure others have experienced this 'mental block', though it is a new phenomenon for me.

Cheers,
Julian

[penna]

Hi Julian,
As you know I too have found the thread very enjoyable and learnt a lot. I hope you shake the dust off the loco soon as I too would like to see how you put the finishing touches to the loco (especially that wonderful Stroudley livery?) and your report of running her in steam! We all want to know how your early refinements of the original Evans design workout.
I hope the 'mental block' soon lifts.
All the best
Patrick

[Deleted]

Hi Julian

Sorry to read that you've sold more models, hope things brighten up and that you manage to get back into building Stepney soon, I'm sure that I'm not the only one who'd want to see you do more on the loco, it's a very good model that deserves to be finished by your talented hands sir..

Kind regards

Pete

[danlank]

That's a real shame Julian, hope you get your mojo back soon! We're all looking forward to seeing the finished article when you're ready :-)

[builder01]

Hi Julian,

Just wanted to let you know that this thread, convinced me that could build my own copper boiler using only propane. Using your construction techniques, my boiler was certified in May and I have been happily riding behind it ever since. I know, you already know this, but, I feel it is important to make sure others know. You have been quite a source of inspiration. I hope you soon get inspiration as well, to continue your projects.

Thank you again,
David (Erie, PA)

[chris vine]

Hi Julian,

Yes, I too, hope you get your mojo back. Your talents are too great to lie idle.

How about making the transportation case for the Terrier? The empty box would certainly be an impetus for progress!!

All best wishes
Chris.

[page]

Dear Julian,
I'd like to add my shout for getting your mojo back. You were very kind a year or two back and freely gave me a lot of extremely useful information for a Terrier model.
I do hope you can continue with Stepney- and keep us informed of progress.
All best wishes.

[dscott]

This is one of the reasons that many of us do many models? Yes, we hit a snag or have made something that does not fit!!
A workshop is a great place to go and recharge... Yes many of us crossed Reading this afternoon and attended one of our
member's funerals. The family described the Party afterwards as a celebration of his life, and it was.

Return home and devise a method of freeing up 8 plumber blocks suitable for going over our aging raised track. File the
doughnut shape of one with a diamond file and use it as a hone each time then swap the next bearing out and in with a
now easy motion of fingers instead of the axle. I had thought of doing each one filed but this worked superbly just taking
off a skim.

My Terrier is in pieces like a Modelworks kit on a bad day waiting for the replacement workshop floor to go down. Again
just do bits while waiting for the glue to go tacky! Yes, you guessed it, the whole place has to be moved around, floor done
and moved again!!!
Best wishes.
David.

[runner42]

Hi Julian,

yes I agree with you that it is silly to allow this self imposed estrangement from the workshop and Boxhill to take hold. I expect the family and the cat are wondering what is going on. You didn't indicate that you have undertaken alternative activities to occupy your time, remember boredom is a health hazard. I remember that you urged a certain Flying Scotsman builder to hurry up and finish the cylinders so we could all see the progress, so now I am applying the same pressure to you to finish Boxhill. Show us you can still hack it!

Brian

[johnthepump]

Yes Julian you need to get back in the workshop and carry on. What would Arthur G. think if he knew you had stalled.
Chin up and back to it.
Best Regards John.

[75C]

Hi, once again I have resurrected my project namely Boxhill, after many obstacles and distractions, some not of my making, and others equally interesting. Too many on the go.
At present marking out the frames again just to check that the original measurements were correct. Anything to watch out for at this stage? Thank you for any information.  Very interesting reading about other people's skills and achievements.   Regards Steve

[jma1009]

Hi Steve,

With regard to the Martin Evans' frame drawing for Boxhill there are no errors as such. However, you might like to consider a few points:-

1. The guard iron holes are far too close together to get a spanner on the bolt heads for the middle bolts

2. "All holes No.27 unless otherwise stated". No.27 is IMO too big as a clearance size for 4BA, and in any event I would also say that 4BA fixings are far too big. I used 6BA throughout. Note that it is not easy to accurately spot through the clearance size, and you would be better off drilling the frames the tapping size and spot through that size into frame stretchers, motion plate, cylinders etc. Only after this open out the relevant holes to a close clearance fit in the frames.

3. Allied to the above, have a good look at your hornblock castings and drill the frames slightly undersize for the rivets. (I used 1/8" iron rivets because I have an aversion to 3/32" dia rivets on 5"g locos for fixing the horns to the frames). At some later stage spot through from the frames into the machined hornblocks. It is easier to spot through from steel into gunmetal than the otherway round.

4. The row of holes for the bottom of the smokebox is a pain as the bolts or screws cannot be removed later on without removing the running boards and everything else attached to them. There is something to be said for omitting the rearmost of these holes as they are obstructed by the front wheels, and omitting all of them, or else raising this raised section of the frames by 1/16", and raising the line of these holes by 3/32".

5. The 'oblong' cut outs in the frames with rounded ends either side of the driving wheels in fullsize mirror each other in height and distance from the top and bottom of the frames. Martin Evans deliberately altered the front cut outs to apparently have somewhere to bolt the R-H crosshead pump.

6. There is room to fit a proper frame stay in front of the firebox throatplate instead of the bit of thin plate with tube attached shown on sheet 1.

7. There is precious little frame staying further to the rear of the Martin Evans drawings.

8. The weighshaft bearings as drawn are very slender. If the weighshaft is extended to be the outer width of the frames, and the frames drilled accordingly for the weighshaft position and opened out for an extended bearing then I consider this to be a big improvement for the valve gear. (The fixing holes for the bearings then need to be further apart than shown on the drawings).

9. If you propose to fit the Martin Evans' type balance pipe described much later on in the construction series then the holes required for it are not shown on the frame drawing.

10. Fit the cylinder block 1/4" further forward. The cylinder fixing holes do not need altering, but again 4BA is far too big IMO and 6BA more than adequate.

I have probably forgotten a few things, for which apologies in advance.

Cheers,

Julian

[75C]

Hi Julian, thank you very much indeed for all this information, greatly appreciated, and the time spent to post it. A lot to think about and it will save a considerable amount of effort trying to sort out problems later on. In the meantime, regards Steve.

[Jim Scott]

Hi Steve

Good to hear of another Boxhill build.

Please check your inbox, pm sent

Regards

Jim S