Mark

3 hours ago, CF MRC said:

If the model is accurate in the bodywork, then a conversion to P4 or EM FS would really make the engine ‘look right’ wrt to the wheels and the boiler; it would appear more ‘planted’. The traction in P4 would also be rather better as there would be less sideways slop between wheel and rail.  The front wheels on Rocket are very characteristic and would benefit from a carefully modelled representation.  I feel a project coming on...

 

Lion would also be a no-brainer, for all sorts of reasons.

 

Tim

This crossed my mind too, but have they had to compromise the basic dimensions to fit between 00 wheels? The firebox and boiler might have been narrowed to fit so it might look odd in P4.

Mark

On 08/12/2019 at 16:29, SR71 said:

I've had these of unknown origin in the spares box for years and just used a few on an ejector pipe. I could do with some more, some different sizes, and some blind flanges. Does anyone produce such a thing?

 

Brassmasters do some which are very good

Mark

4 hours ago, Harlequin said:

Locos are wonderfully detailed these days (although not all the details are always correct!) but I realised that all my GWR locos were missing something: Brass washout plugs. The plugs themselves are usually very carefully moulded but they are not coloured...

 

So I had a go at addressing this using some ATK Brass True Metal Wax:

 

This product is thick and has a high pigment level, which means that just a touch completely obscures whatever colour is underneath. This is important because it would be unthinkable to try to paint such small, recessed details let alone having to use multiple coats!

 

I picked up some of the wax on the end of a cocktail stick and, using an optivisor to magnify the view, very carefully touched each plug-head to transfer the colour.

 

The results are very pleasing. Maybe the brass is a bit too shiny but that will get toned down when the locos are weathered.

 

There are a few mistakes to be cleaned up but not so many to put me off doing more in future.

 

I have never seen Brass Washout plugs so I have just looked and found the following heritage railways document that specifically rules out the use of brass. Where did you find they were made of brass?

mark

I asked why WHSmiths put MRJ on the top shelf the last time. They didn’t provide me with a brown paper bag to disguise my purchase!

mark

On 22/11/2019 at 22:53, Darwinian said:

I have started the 3000gal tender for my Martin Finney Aberdare.

How can I get it round my track curves (about 3rd radius minimum). There’s only about 0.5mm clearance either side of the well tank so the middle wheels cannot move to accommodate curves. Also the bearing slots for this axle are so large the pinpoint bearings just fall through.

 

 

Anyone successfully built one of these in 00?

You should have a longer axle for the middle wheels with top hat bearings supplied in the kit and not pinpoint. The middle axle should slide through the top hat bearing and this should give you clearance. 3’ radius is a bit tight though. You   Might have to remove some material from the well immediately behind the middle wheels for clearance. These kits are designed for Wider gauges where there is plenty of clearance behind the wheels and it is possible that the inner clearance limits the 00 curve radius as much as the outer clearance limits the wider gauges.

Mark Humphrys

I use Rhino 3D for my cadds models. The basic structure was created as a solid shell 0.6 mm smaller on each side to allow the bricks to be booleaned on afterwards with a 0.3 mm overhang to allow some depth between bricks for mortar. I did an experiment using 0.15 mm deep on a chimney stack first in the picture below.

unfortunately the brickwork is English bond and close examination of the building has required a lot of effort to position bricks to obtain the right position of openings. This means that layers which are predominantly stretchers have the occasional header along the length. I don’t think this can be automated. 
 

i have also started to paint the main structure now.
 

Regards

Mark Humphrys

I have had a go at printing the water tower for Brent. The base and tank are separate parts. I have etches to use as overlays on the tanks so the slots are provided for clearing tabs on some details to fit to the etches. The tank had distorted during the build and was slightly too short so is being done again.

I used a 0.2mm gap between the bricks a layer thickness of 0.02mm and an exposure time of 7.5 seconds to try and minimise light bleed. The building was grown perpendicular to the build plate. Scale is 4mm:1ft

Regards

Mark Humphrys

Has anybody tried to install the latest Photon S slicing software? It has a number of upgrades the most useful being able to divide the print area into 8 different Build zones which can have different build settings. So you can try 8 different settings simultaneously to optimise your model. 
 

I have installed the software successfully on a Windows 10 lap top but the software fails to start when I try to run it. Anybody got any ideas?

Thanks in anticipation.

Mark Humphrys
 

Quick question. Hopefully without causing too much consternation!

Is this coach being built in contemporary form?

 If not the electrification warning flashes are too modern.

Regards

Mark Humphrys

19 hours ago, Porkscratching said:

I recall a post somewhere on the forum, not particularly recently, suggesting use of a slide rule to make simple conversions or take dimensions from one scale to another..

For instance, I would like to take dimensions from a 7mm to the ft. model or drawing, and convert them with as little maths as possible to 10mm to the ft. scale... Now it was suggested this could be done by simply setting a slide rule and reading off the result..this sounds like it'd be ideal... Any idea how you'd do this ?.

If it's a "goer" I can doubtless get a slide rule off evilbay for pennies !

Also are all slide rules marked the same ?

How about drawing a right angle triangle. For the base draw a line 300mm long which is equivalent to 30’ in 10mm scale. On the vertical axis draw a line 210mm long which represents 30’ in 7mm scale. Draw a line linking the end of both lines (The hypotenuse of the triangle). You could divide the 7mm line into 30 7mm increments and the 10mm line into 30 increments of 10mm. So all you have to do then is look for the size on your 10mm line that you want to convert and then draw a vertical line which intersects the hypotenuse. At this point draw a horizontal line and it should intersect the 7mm scale axis at the equivalent 7mm scale of your 10mm dimension. So for example 100mm on the 10mm scale should come out at 70mm on you 7mm scale. You can do the same in reverse to convert the other way.

Regards

Mark Humphrys

They are looking good.

Are you planning on printing the glass using clear resin? I have been doing some experiments with MK1 coach windows with varying degrees of success. Getting rid of the steps was quite easy. I just painted some resin on the rough side and then laid it on some cellophane sheet and then exposed it to UV light. The problem I am finding is light bleed is a lot more obvious and the parts are coming out with a faint orange hue. I have reduced the exposure time as much as I dare.

I have been following this thread with interest and succumbed with a photonS. After a few failed attempts because I didn’t give enough curing time and a replacement FEP I have successfully printed a set of MK1 coach axle boxes and leaf springs. Conscious of the issue of light bleed I pondered how to get the laminations on the springs to print and concluded that the best way was to create each spring lamination individually and sweep a sharp pencil profile along the curves before booleaning the laminations together using Rhino 3D. I am quite pleased with the results so far.

16 hours ago, Jeff Smith said:

Yes, it seems so from photos of the real thing and official GWR drawings.

 

Now to progress with the chassis.  The etched axle bearing 'holes' have been removed and the new sprung axle blocks and springs installed.  The block slots were opened up slightly with a triangular swiss file  to allow the slight side to side axle tilt required.  The etched dummy springs were bent aside to allow the axle blocks to be slid into place.  Prior to all this the etched axle location was marked on the sideframes to ensure that the sprung blocks covered the right range.  Height measurement of the footplate and smoke box when sitting on three wheels as indicates that the smoke box centre is about right but the buffer beam a bit low.

Yes the drawing you have shown is an official GWR drawing but it is a weight diagram and these are notorious for their inaccuracies. The drawing I referred to in my post is the frame diagram published in Great Western Journal and also an official Great Western document and generally far more representative than weight diagrams which are really only intended for axle loadings.

Regards

Mark Humphrys

Using the GA in Great Western Journal it is about half an inch higher from front to rear. I have completely redrawn new boilers for my mitchell Moguls and spent quite a bit of effort puzzling over this but visually the new one looks correct.

Be careful of photos taken at rail level because the firebox is wider at the front than the rear and as such parallax can give some quite substantial visual errors.

Mark

19 hours ago, Craigw said:

 

Jeff, they were built with the porthole windows above the firebox and this feature was gradually removed from about 1925 onwards. Three things started to occur to GWR locos from around 1925 - the portholes were blanked over and new front plates were eventually fitted, a low vacuum pipe was fitted and heavier springs were fitted to tenders. The attached is a photo of one with the windows. Photo is from a negative I won on Ebay.

 

Regards,

 

Craig W

Is that taken from Ponsondane level crossing?

Regards

Mark Humphrys

13 hours ago, AY Mod said:

 

Such stigma pales into insignificance compared to leaving random alien objects in shot compounded by them going unnoticed in the photoshopping process.

 

Aside from the object in the distance how has the tractor ploughed the field both in front and behind?

Regards

Mark Humphrys

As you have several to do it may be worth making a tool. Maybe a ‘u’ shape with three 0.45mm holes drilled in it. Two holes to line up with the holes in the existing handrail knob and one hole in the bottom centre of the U to locate the drill for the new hole. The U should be the same width as the handrail knob. Thread some 0.45mm wire through the two holes in the vertical walls of the U and through the handrail knob and then drill the extra hole using the hole in the bottom of the U to guide the drill.

you could fabricate the U section by taking two pieces of scrap etch with holes pre drilled for the vertical edges and then use some more scrap etch to space them apart. You could avoid drilling a hole at the base of the U by using three layers of scrap with the middle layer made up of two pieces with a small gap between them for the hole. This will then guide the drill.

Hope  you can. Visualise this.

Regards

Mark Humphrys

10 hours ago, The Fatadder said:

I am trying to work out how I am going to build the tops of the platforms for Brent

 

looking at prototype photos the surface is a mix of paving and loose gravel.  The edging is made of brick as per below 

 

however I am struggling with what goes inside the brick.  Looking at prototype photos even on the gravel sections of the platform the width of the edging is a lot thicker than the brick that remains today.  Was there a line of paving slabs between the brick and the gravel?

 

Has anyone been successful in modelling this type of brick platform edging?

 

thanks

 

 

There is a line of paving slabs all along the edge apart from by the signal box which had concrete panels to cover the rodding routes. Originally the areas covered by slabs were covered with diamond embossed brick.

I made a brick edged platform years ago for Chagford Road and I think I did it by gluing strips of plasticard on the top and cutting vertical slots on the edge. I then radiused the corner with some sandpaper. 

Peter Cross used to do some etchings of the edge bricks.

Regards

Mark Humphrys

On 21/06/2019 at 02:40, The Johnster said:

This is getting to be a regular subject; someone bemoans the lack of an available RTR Manor to modern standards and we all chip in with our 5 penn'orth.  Despite the Manor being a persistent big hitter in polls and on wishlists, no model is in current production or announced for future production,  and the only source is secondhand Mainline and their Bachmann derivates from 'Bay.  These are all based on the old Mainline tooling which Miss P has criticised above.  Boiler taper aside, it suffers IIRC from an over-wide firebox but is otherwise not a bad offering appearance wise for it's age, with a cab clear of motor and fully detailed.  But the Mainline had one of their split chassis with the consequent issue of reliability associated with these, and I am unfamiliar with the various later Bachmann versions but they are pretty outdated now and not up to modern performance standards.

 

Nevertheless, if you want a Manor now or in the foreseeable future this is your only current option.  The consistent performance in polls must surely mean that somebody is working on the idea for the future, but how long into the future is at best a moot point and you might have to wait years.  Bachmann are currently taking about 5 years to bring models to market after announcing them, and Hornby do things differently, not announcing until they are nearly ready to produce, so who knows if they have something in the pipeline.  Dapol and Heljan are playing their cards equally close to their chests, and change the subject if you mention it to them.  All of them might be holding back to avoid the sort of duplication that Hornby have had, or contributed to depending on your point of view, with the Adams Radial, Terrier, 14xx, J94, and Large Prairie.

 

Hornby are in a fairly strong position to produce a Manor, having already produced a suitable chassis and mechanism for their Grange, and it is possible to upgrade a Mainline Manor with a Hornby Grange Chassis, but there's not much space and a lot of filing and fitting is involved and the chassis has to be shortened at the back.  Similarly, the Dapol mechanism to be produced soon for their 43xx and Large Prairie can be used for a Manor (some Manors were rebuilds of withdrawn 43xx), and by the same token so can that from the new Hornby Large Prairie.  But this is a stage beyond RTR OOB modelling and one would have to fit the mech to the Mainline body moulding, and fabricate mounting brackets and fixings for it as well.  

 

Or there's the Comet chassis kit, again probably a bit of a commitment for anyone used to OOB and not cheap.  None of the other kits are IMHO up to the standard of the Bachmann, which is itself not perfect, and hence to my mind pointless, with the exception of the Mitchell if you could source one, but that is a very major outlay and really more of a scratch build aid.  

 

The good news if you are modelling GW or WR steam is that you can get away without having a Manor on your layout at all, desirable though they are, unless you are modelling the Cambrian section or Ruabon-Barmouth.  But that doesn't stop them being a very attractive prototype whose popularity is maintained by the relatively large number of the class that have survived into preservation.  They are, for layouts based later than the very earliest BR days, the smallest named GW locos you can use, and this also plays to their popularity among modellers; shorter than a Grange or Hall and this is important on layouts with limited space where every mm counts in sidings and on fiddle yard roads.

I don’t think it is fair to describe the Mitchell Manor as a scratch building aid. It is a complete kit and fully buildable. I am working on one at the moment and the changes I have made are to suit my personal preferences rather than anything intrinsically wrong with the kit.

This one is intended for double heading a King in the Mid 1950s and will be done in plain black as 7820 which was a Laira engine at the time.

Image below of parts balanced together. Nickel silver bits are mine to replace kit parts to get finer boiler bands and a finer smokebox door.

Mark Humphrys

14 hours ago, Miss Prism said:

British Rail Main Line Diesel Locomotives, Colin Marsden and Graham Fenn, OPC

 

I would take this book with a massive health warning as a large proportion of the drawings are incorrect or at best include a substantial amount of artistic interpretation. Actual engineering drawings of Diesels are very hard to come by and with exception of the LMS twins very little has been published that emanates from reliable sources.

Regards

Mark Humphrys

16 hours ago, Lyonesse said:

My own practice is to cut the boiler bands from 0.002in nickel with a scalpel, using a sheet of tinplate as a cutting board.  Drawing them through folded emery paper removes the burrs.  I have to throw away about 1/3 of them but they're easy to make.  I don't bother trying to get the proper developed shape --- and I doubt that Swindon did either, although I'm prepared to be corrected on that point.  Anyway, it works for me.

 

I'm still intrigued by the smokebox door.  Is this an assembly we're looking at, turned door with soldered on shed plate, hinges and 'rivets' fitted into drilled holes?

Several years ago I did a Scratch built Hall for which I cut the boiler bands from very thin sheet in straight strips. I found they had a tendency to crease when being forced to follow a conical shape. I found be etching them to the local coning of the boiler that fitting them was easy because they naturally follow the shape of the boiler when they are fitted.

The smokebox door was done as several separate parts. The domed door was turned on a lathe using co-ordinates from a cadds cross section to cut a series of small steps. I used 64 thou Nickel Silver sheet soldered to a brass bar for turning. The door frame was done in the same way. The hinge straps were done using a CNC machine to try and develop the bevel edge at the inner end of the straps. The straps were soldered to the door with the aid of a small locating jig.

The hinges themselves were made from 4 pieces of 0.9mm dia tube with a 0.45mm bore. Each pair were located over a 0.45mm OD 0.3mm bore tube to align them and finally a length of 0.3mm Nickel Silver rod was passed through the bore for the hinge pin.

The shed plate soldered to the door is from an etch I did recently and the small pins around the top hinge are to give me a location for the smokebox number. I considered making s ‘U’ shaped bracket but fitting it to a curved surface and getting the top flat seemed too difficult and fiddly so I came up with the idea of soldering four 0.3mm diameter pins and then filing them down the correct length. I am still pondering soldering the number plate on before painting or glueing afterwards.

i still have the lamp bracket to fit and will probably use 0.3mm rod to pin it to aid location for assembly.

I have added some more photos below if the door and another to illustrate some of this.

Regards

Mark Humphrys

12 hours ago, Lyonesse said:

Very nice indeed.  This is 4mm scale?

 

These days I replace the boiler and firebox but keep the smokebox.  As you say, the etched on boiler bands are too thick and a replacement boiler with 0.002in shim bands looks much better.

 

How did you make the smokebox door?

Yes the model is 4mm in P4.

The smokebox door was done using a lathe to get the profile and the hinge straps were done on CNC machine.

The boiler bands are half etched from 6thou Nickel Silver and were drawn for the correct conical shape at their respective location using a 3D cadds model to get the developed shape.

Regards

Mark Humphrys

Is the shape of the outer windows correct in the front? It looks like they have the radius at the top corner too tight with an extended straight section at the top. This is the same as the 7mm version which to my eye lets it down.

Regards

Mark Humphrys

40k sounds like a lot of money, but just go and do a simple valuation of your stock at current list prices. It is quite scary!

Regards

Mark Humphrys