BOXHILL by Martin Evans

[jma1009]

hi ed,
yes.
cheers,
julian

[jma1009]

i sent the ME stuff to pete about duplex gauges. having re-read the stuff again in the course of the above i might even have another go at a second home made pressure gauge! watch this space! ive a whole drawer full of old commercial miniature gauges ive been given over the years. most are pretty horrendous with bourdon tubes made out of shim soft soldered together or have badly corroded being made of brass bourdon tube.

i was lucky enough to know very well the late freddie dinnis whose miniature pressure gauges were excellent and adorn many brilliant locos plus were used by Rolls Royce. all my locos have freddie dinnis (FSD) pressure gauges apart from the one i made myself. i think you have to be a bit of a masochist to make such things yourself, but it's quite nice to stand back and say every fitting is 'home made' from injectors to pressure gauge. having seen how some of the miniature commercial stuff corrodes with inferior brass bourdon tubes, i would encourage anyone with good eye sight and an accurate lathe to 'have a go'!

the cylinder drain cocks are all finished with handles now btw.

cheers,
julian

[ejparrott]

ooooo......I'm really tempted......

[sparticusrye]

I will be interested to see the construction of this gauge when you do it. My Pamela has a purchased gauge on it right now. Maybe after seeing one made I would be tempted to try it myself for the engine I am building. What is used for the bourdon tube in minature gauges? Squat copper tube sealed at one end?

[jma1009]

hi sparticusrye,
in fullsize bourdon tubes were made out of phos bronze drawn to a 'D' section. roy amesbury's were made out of sifbronze rod machined on a mandrel and then flattened and curved by hand using different formers and shaped shim. no one knows how freddie dinnis made his phos bronze bourdon tubes curved and 'D' shaped as the 'secret' died with him. i know how he made the drawn tube, but not how it was subsequently curved.
apart from the freddie dinnis gauges, none of the commercial miniature gauges ive been given have properly made 'D' section bourdon tube.
cheers,
julian

[Deleted]

Not wishing to high jack Julian's build thread I'd just like to say that I will of course give full details of making the gauge in 4472's build thread once I have made a start.

A big thank you to Julian for supplying me with the drawings... as a side note I do intend to make all of the fitting for 4472 when I get to that stage, I wish to make them as close to the prototype as possible even if in some cases it's only cosmetically.

Should be fun with a little frustration thrown in...

Pete

[jma1009]

ive been faffing about with the cylinder drain cock linkeage on my STEPNEY the last week or so.

the fullsize arrangement is quite special, and to get anything near it ive had to exercise the grey cells.
anyway i think im nearly there as the following pics hopefully show.

in fullsize the drain cock linkeage runs underneath the left hand running board, then via  a handle in one side of the frames on the outside that works another handle on the inside of the frames to work the cylinder drain cock valves. ive had to make up a special removable handle on a square and 6BA bolt to make the bit that goes through one side of the frames, the handle on the otherside being silver soldered on. in the final pic you can just see on the lefthand side the forked linkeage from that to the crossbar with all the other handles added. these are silver soldered onto (after turning down between centres) 1/8" dia steel tube drilled and reamed 3/32" dia. if i said this was fiddly it would be an understatement - but more in working out how to fit same rather than make.

i cant screw in the rear cylinder drain cocks with their handles and plugs attached without removing the cylinder block from the frames due to clearance with the proper spring leaf spring sockets riveted to the frames. no problem as it all needs to come apart one final time anyway.

ive no drawings for any of the above - just a few pics of fullsize and a wing and a prayer! sorry about the poor pics - very difficult to photograph accurately and clearly

cheers,
julian

[Deleted]

I like that set up Julian... very neat and purposeful..great work..

Pete

[jma1009]

thanks pete!

it all looks a bit of a mess at the moment, but im getting there slowly.

cheers,
julian

[jma1009]

not much progress to report, but i think ive finished all the drain cock linkeage at the front end. it all works anyway if not as neat as i would like!

i think the next job is the A1X sandboxes. not quite sure how to make them yet, and ive got a rather big job to do on the house before xmas so the workshop wont get used for model engineering for awhile!

cheers,
julian

[jma1009]

a recent exchange of emails reminded me i had this pic of the frames set up back to back in my dore westbury mill to machine the hornblocks. quite a heath robinson-ish set up but it did the trick. 'new' long end mill used very slowly downwards (i've a few i keep only for such jobs). april last year - seems along time ago now!
cheers,
julian

[jma1009]

here's a pic of the LBSCR 'A' diagram wagon springs so far. the top leaf is done with it's awkward sharp bends at the end. wagon stuff is something quite new to me and i can now appreciate the wonderful scale wagons ive seen in 5"g. mine isnt 'fine' scale, and is made out of all sorts of bits of hardwood drawers and bits of wood ive collected over the years and various odds and ends. the axleboxes are machined out of round bar, with separate covers that are etched "L & B S C Ry" as per fullsize.

the spring making was discussed in another link

modeleng.proboards.com/thread/8817/spring-steel-strip-1-16th?page=2

the black springs are bits of curved black plastic bleach bottles cut up into strips. still got to do a bit of adjustment to the springs which wont probably be finalised till ive made all the other bits plus a removable coal 'bunker' and water tank to fit inside.

cheers,
julian

[johnthepump]

Hi Julian,
Good luck with this very interesting project, I would also like to wish you all the very best for the coming New Year, maybe we may see on the Island again one day,
Regards John.

[jma1009]

well, after a 2 month break nearly finishing the 5"g LBSCR wagon have restarted on STEPNEY's boiler.

first job has been to make the smokebox tube plate. this is 3mm copper, hacksawed and filed to a disc. the former is a bit of mahogany with a handy disc of cast iron clamped the otherside to prevent distortion whilst whacking the annealed copper.



this is the disc on the second annealing. the thermalite blocks are arranged to contain the heat. takes about 2 minutes to get up to heat.



the most difficult bit is the first bashing. this is i think after the third annealing. i think there were 5 or 6 annealings. note the bucket of water nearby!



here's the completed smokebox tube plate trial fitted after a slight touch up on the outer diameter in the lathe and truing up the flanged end (hidden), and drilling and reaming the holes for the tubes, and using a counterbore for the superheater flues. on this type of boiler you can slightly vary the tube spacing to get a more even layout than at the firebox end, and raising the tubes 1/16" or 1/8" also helps a bit with better spacing.

when drilling copper there is usually quite a burr - i drill from both sides alternately to remove the burr. really sharp drills with the edges backed off a bit helps of course, plus something like WD-40 as a lubricant.

one of the problems with the smokebox tubeplate former being made of wood is the difficulty of removing the flanged plate from same when finished - anyone who has done this before will know what i mean! it actually took longer to release the flanged plate from the former than it did to make same!

cheers,
julian

[GWR 101]

Very nice work Julian well impressed , am I correct in assuming that you use propane for the heating ?. Also just noticed the G clamp in the last photo, looks the same as the one I have, sawn out of a steel block as an apprentice. Regards Paul

[jma1009]

hi paul,
yes ive only ever used propane, apart from the infamous 1 gallon paraffin blowlamp on my first boiler! i dont have the skill to use oxy acetylene and have heard too many horror stories of use of same except in the most experienced of hands with miniature boiler work. im quite happy with my sievert propane equipment. it avoids localised overheating etc.
cheers,
julian

[GWR 101]

Looks like that's the way to go then, and with the use of the blocks from the builders (suitably dried out) to make a hearth. I have not undertaken any boiler work yet but hope to be there soon on my 3 1/2" build, so I will take look at the Sievert propane kit. Many thanks Paul

[runner42]

Hi Julian,

what's the kW rating of your propane torch? Do you require background heating as well when silver soldering a large mass of copper?

Brian

[uuu]

To save Julian looking it up, I can read off the card in my set:

Burner 2941 is 7.7Kw, 2942 is 26Kw, 2943 is 43.5Kw and 2944 is 86Kw.

The picture looks most like the 2942.

If you can find a second hand boxed kit, you're well set up.

Wilf

[Deleted]

This currently on E-Bay........... www.ebay.co.uk/itm/Sievert-P3444KIT10X-Detail-Roofing-Burner-Kit-10m-Hose-/181317881184?pt=LH_DefaultDomain_3&hash=item2a37 -------------