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Ian Smith
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Todays project was a Loading Gauge.  The one I made for St Ruth is of a later design with a post from 2 lengths of bull head rail bolted (or rather soldered) together, but for Modbury's early period I felt that a timber post version would be much more appropriate.  There is a photo of quite a nice one at Malmesbury in Stephen Williams' Great Western Branch Line Modelling (Part 2), and it was this that I based my model on.  Having no actual drawing of a timber loading gauge, I used a drawing of a rail built example to get the basic measurements and scaled the Malmesbury photo on the known dimensions of 9'8" across the width of the gauge, and 13'6" from rail head to underside of the gauge.

 

LoadingGauge.JPG.6695268a0051d774ff31431c24424501.JPG

A somewhat cruel close up of the finished loading gauge after painting - the whole thing is only 40mm tall!

 

My model started out as an aborted signal post (I'd milled the taper at too steep an angle).  The taper of the post was corrected by careful filing, an oversized piece of 0.010" etch was soldered onto the top of the post then filed back until it was just proud of the post all the way round, and then the post cap was filed to have a slight taper from middle to edges.  The cross bar would appear to be about 3'0" from the top of the post, so a length of 1mm square brass bar was prepared for the cross bar with a small piece of the same material soldered along the side at one end.  This extra bit was attacked with needle files to produce the ornamental strengthening piece evident where the cross bar buts up to the main post, and once I was happy the cross bar and main post were soldered together 6mm down the post.  The main post itself also has a carved wider section at the door of the post, so a bit of 0.028" nickel silver was sweated onto the side of the post an it too was attacked with needle files until I was happy with its shape and size.

 

A 0.3mm hole was drilled at a slight angle near the top of the post for the straining wire, and a pair of holes drilled in the cross bar for the same straining wire (the hole nearest the post being where the straining wire enters the cross bar and a hole a mm or two further out for the bit of the wire that appears on the far side of the cross bar with the nut on it.  A length of wire was soldered in place to represent the straining wire then cut back to size.  Further 0.3mm holes were drilled through the cross bar for the chains that the gauge was suspended from.

 

The actual gauge itself was carefully bent up from a length of 0.6mm wide nickel silver strip - on the last etch I had done I filled up an odd space in the artwork with a sub-etch of 0.5 and 0.6mm wide strips as I thought they might be useful one day!  The chains were made in the same way that I make handrail knobs for my locomotives, a loop of thin wire (very thin in the case of these suspension chains) has the two tails trapped in a pin vice, the loop passed over a drill in another pin vice , and the pin vice with the loop in spun until a tight twist of wire is formed with an "eye" around the drill.  The eye was slipped off the drill, and passed over the bent up gauge and another made - rather surprisingly I only needed to make the two as I didn't lose any!  The suspension chains were tack soldered to the gauge and the ends of the chains threaded through their holes in the cross bar before being secured in place with another quick in and out with a soldering iron.

 

The various solder joints were carefully cleaned up (especially around the various bits of wire), and finally the securing metal strap added (from 0.005" plasticard) where the cross bar meets the main post.  A coat of white primer, a touch of Precision Paints Dirty Black around the foot of the post and then various washes of much thinned Dirty Black completed the loading gauge.

 

Tomorrows task will be to site it on the layout, it is intended that the loading gauge will go on the goods loop, and be used as a marker for the uncoupling electro magnet.

 

Thanks for looking.

 

Ian

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2 hours ago, richbrummitt said:

RHS looking much improved with more trees sprouting.

 

Took a couple of attempts to figure out what you said there. I was wondering what the Royal Horticultural Society had to do with Ian's trees.

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Well worth the time and effort Ian, not always easy to get the proportions and planting correct but I think you've certainly improved the layout with these additions, not forgetting the loading gauge too.

 

G

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Over the last couple of days, I've made a start on the next loco for Modbury - a Deans Goods.

 

The tender chassis is made in the semi-traditional way using frames of 0.5mm phosphor bronze fretted and filed to size.  Although I have used soldered PCB for the frame spacers rather than the truly traditional Tufnol blocks screwed to the frames.  The wheels are some from the late '80's/ early '90's, having a cast centre and nickel silver tyres (these were originally bought when I was a member of the 2mm Association first time around and were actually purchased for a Dean Goods that I hoped to build at that time).

 

The loco chassis is made from what is now my usual milled chassis method (both my Metro Tank and Buffalo Saddle Tank have milled chassis).  The chassis block being milled from pieces of 6mmx6mm bar and 1mmx6mm strip bolted together (with an insulating barrier between them).  Currently, the pair are temporarily bolted together outside the finished chassis length.

 

The state of play at the moment is that all of the holes have been drilled, the spaces for the axle muffs and gears have been milled away and the axle holes have been fitted with phosphor bronze bushes.  The next job is to araldite some plastic plugs in the holes in the main chassis block (the 6mm square bit) for the permanent chassis bolts.  Once cured, the plugs will be drilled and tapped 12BA and the 1mm thick frame fixing holes countersunk for the permanent fixing bolts.  Once the chassis is securely bolted together the task of milling/filing the chassis profile can begin.

 

DeanGoodsChassis.jpg.e3d35022598a9866c1dbfdf3fe13e0da.jpg

The plan...

 

Chassis1.JPG.48e1531cd0d2ea21b614e960394ea071.JPG

Where I'm at ...  The coupling rod is temporary - I'll be making up and using my custom etched version fish-belly version for the same wheel spacing.

 

Thanks for looking.

Ian

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I will look forward to this Ian, it's no secret that it is one of my most favourite GWR Loco's.

 

May I ask which type of boiler you intent to model ? Assume / hope it will be the round topped version, without getting into detail I think it would certainly suit your modelled period.

 

G

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2 hours ago, bgman said:

I will look forward to this Ian, it's no secret that it is one of my most favourite GWR Loco's.

 

May I ask which type of boiler you intent to model ? Assume / hope it will be the round topped version, without getting into detail I think it would certainly suit your modelled period.

 

G

Graham,

The Dean Goods will indeed be a round-topped firebox version. Need to do a bit more research to find a suitable candidate as I know there are a myriad of different combinations of foot plate width/boiler and smoke box type, dome size and position, etc, etc.

Luckily all of them had the same wheelbase so a chassis will be pretty generic for any of them :rolleyes:

Ian

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Thank you Ian, I know there are many variations ( don't ask me how I know ? Usual response ! ) and I certainly found Jeremy Clements book "William Dean : the greatest of them all" a good source of information when building my 7mm version.

 

Enjoy, and above all keep safe and well.

 

G

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@Ian Smith that chassis looks very clean, I would love to see a rough step-by-step if you feel like you have the time to go into it (maybe in a separate WB thread?)

 

I see the diagram you're using alot in the threads here but I can't quite place it QCAD? Is this transferred somehow onto the chassis when you're milling it, or just used for measurement reference?

 

 

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23 hours ago, Lacathedrale said:

@Ian Smith that chassis looks very clean, I would love to see a rough step-by-step if you feel like you have the time to go into it (maybe in a separate WB thread?)

 

I see the diagram you're using alot in the threads here but I can't quite place it QCAD? Is this transferred somehow onto the chassis when you're milling it, or just used for measurement reference?

 

 

William,

Yes, I do draw up my diagrams in QCAD.  I take measurements from the CAD rather than the printed drawing - for example when laying out the multi-stage gearing, I will take a a horizontal measurement and vertical measurement from the CAD, if necessary convert it to thousandths of an inch (my lathe is a Peatol one and is imperial), then on the lathe (set up as a milling machine) will use the back end of a 1.5mm drill to locate the (previously drilled) driving axle hole then move the vertical / top side the relevant distances to locate the position for the spur/gear wheel hole.  The drill is removed from the chuck and replaced with a centre drill so that the gear axle hole can be spotted in the chassis, then the 1.5mm drill replaced and the gear axle hole drilled through.

 

As for a step-by-step walk through of my methods, most of it is described on my Modbury website in the Metro and Buffalo pages (http://www.modbury2fs.co.uk/615.html and http://www.modbury2fs.co.uk/1601.html).  The principles I use are based on those of Nigel Ashton, whose Cambrian 0-6-0 was written up in 3 articles starting in Aug/Sep 2012, my own Metro tank was also described in the Feb/Mar 2018 magazine.

Ian

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I am sorry that you, and countless other intending exhibitors, have had your efforts thwarted this year. So a video is a very good makeweight for those of us who might just have got to an exhibition or two - thankyou. 

 

For those of us at the hamfisted end of the modelling spectrum, 2mmFS is implausibly precise in its demands. I have already had the pleasure of watching layouts by Messrs Clifford and Greenwood, among others, so know that it is not just sleight of hand. But you add baulk road, just to spice it up a bit.

 

Quite remarkable. Thankyou again. 

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A little more progress with the Dean Goods chassis :

 

Chassis2.JPG.d393ef61708c6f189d66f0deb13547b7.JPG

The chassis block has been milled to shape, permanently bolted and glued together and the excess cut off each end.  The wheels have been permanently glued in their muffs (having got them all quartered of course) and the crank pin washers soldered in place and the crank pins themselves ground back to the washers.

 

Chassis3.JPG.36aef30bd17c73978c8efd221ae39f01.JPG

A holder for the worm (and small flywheel) has been milled up too.  A pair of 14BA bolts secure the holder to the main chassis block (the excess hole drilled on the centre line at the tender end was for one of the securing bolts until I remembered that I wouldn't be able to get at the bolt because of the cardan shaft coupling! Hence the offset hole.

 

Chassis4.JPG.8d5712a444001ab95e0abaf470d41792.JPG

The pair united (albeit not bolted together).  The lip at the front of the chassis will be trapped in a socket behind the buffer beam, the chassis-to-body securing bolt will screw into the cab floor through the large hole at the rear of the chassis - I still need to fit a plastic sleeve in this fixing hole so that the body can remain electrically neutral.  And there is a large hole in this side of the chassis that originally would have taken another fixing bolt that I dispensed with (because the gearbox bolt passed straight through it!)  I really need to plan ahead sometimes :wacko:

 

In the end I decided to model one of the later lots, which will have a wider footplate (7'8") and have fluted coupling rods.  It will however have an S4 boiler (large dome on second ring) and a round-topped firebox.

 

Thanks for looking,

 

Ian

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