Cutting Brass Sheet

[billbedford]

Real loco frames are about 1.5" thick

Sorry, which locos, exactly, had 1.5 in thick frames?

 

1 1/8" was more usual though occasionally 1 1/4" was used.

[Sir Balin]

Stephen,

 

Thank you for your helpful and comprehensive reply. Re-reading my original post, I'm horrified at the number of typo's in it. My only excuse is that I was dog tired after a very hard day!

 

Kind regards

 

Ian

[bertiedog]

On frame thickness Bill is accurate, but they did vary a bit with different railway companies, but the amount is barely +- 3thou or so, 6 to ten thou at max, so can be disregarded should you wish, unlike the difference between a scale thickness and using 2 to 2.5 mm plate (or 1/16th imperial) as older designers did.

 

The reason in the UK that 1/2^th and 3/8^th wide 1/16^th thick plate brass strip was used for chassis was simple, you rang Smiths of Clerkenwell, and it was a stock item, cheap, and delivered by return in the 1940/50/60/70 period.

 

Buying in 1mm or any thinner brass strip was a special order, sheet were done, but that meant a cutting charge by Smiths,or time and trouble and expense of setting up a shear to cut the plate.

 

All the makers did was cut from stock strip, it was cheaper. But it did not give a good or accurate product just think K's frames! It also allowed you not to have bearings, a lot were made just with a 1/8^th hole in the 1/16^th side frame.

 

The reason 1/16^th was used in the States was it was scale to the thickness of average bar frames, and as the makers made the models with plate sides rather than bar, 1/16^th imperial brass sheet suited fine. As Japanese models came in with metric dimensions 2mm became common for plate sides of the frames, later dropping to 1.5mm.

 

In the UK it was not till etched frames and kits were introduced, Kemilway and Jidenco etc,that thinner frames came into fashion, and the etched ones were really under thickness at first. P4 forced the main changes along with desire to fit suspension and axle boxes that resembled the real thing, rather than a hole in the brass sheet, without a bearing in most cases.

 

Stephen.

[brossard]

My source for frame thickness was Iain Rice who stated that it was 1.125" - 1.5". I chose to quote the higher figure. In Loco Profiles LMS 4F, it is stated that the frames were 1" thick. The broader point should not be missed in all this minutiae and that is to select a thickness of brass (or N/S) sheet appropriate to constructing a 4mm chassis.

 

John

[Donw]

On frame thickness Bill is accurate, but they did vary a bit with different railway companies, but the amount is barely +- 3thou or so, 6 to ten thou at max, so can be disregarded should you wish, unlike the difference between a scale thickness and using 2 to 2.5 mm plate (or 1/16th imperial) as older designers did.

 

The reason in the UK that 1/2^th and 3/8^th wide 1/16^th thick plate brass strip was used for chassis was simple, you rang Smiths of Clerkenwell, and it was a stock item, cheap, and delivered by return in the 1940/50/60/70 period.

 

Buying in 1mm or any thinner brass strip was a special order, sheet were done, but that meant a cutting charge by Smiths,or time and trouble and expense of setting up a shear to cut the plate.

 

All the makers did was cut from stock strip, it was cheaper. But it did not give a good or accurate product just think K's frames! It also allowed you not to have bearings, a lot were made just with a 1/8^th hole in the 1/16^th side frame.

 

The reason 1/16^th was used in the States was it was scale to the thickness of average bar frames, and as the makers made the models with plate sides rather than bar, 1/16^th imperial brass sheet suited fine. As Japanese models came in with metric dimensions 2mm became common for plate sides of the frames, later dropping to 1.5mm.

 

In the UK it was not till etched frames and kits were introduced, Kemilway and Jidenco etc,that thinner frames came into fashion, and the etched ones were really under thickness at first. P4 forced the main changes along with desire to fit suspension and axle boxes that resembled the real thing, rather than a hole in the brass sheet, without a bearing in most cases.

 

Stephen.

 

You quote 2mm to 2.5mm plate as 1/16th inch . I would suggest 1/16th is under 2mm but still way oversize for 4mm. When I started modelling seriously in the 60's it had become accepted as the norm and few questioned it. In those days detail below the footplate was rare. I can remember letters in the model press suggesting that scale size frames were unworkable but as you say etched kits and P4 were showing otherwise.

Don

[bertiedog]

Not really confusing 2 to 2.5mm and 1/16^th at all, there was the word "or" in between, and most modellers in the UK and States used 1/16^th brass strip, but if supplies were metric 2mm was common, and 2.5 the thickest used. Under 1mm Brass plate was almost un-obtainable for hobbyist uses in the UK in the post war years.

 

3/32^nd was rarely chosen, unless brass "Kick Plate" was sheared up to used, old brass name plates etc., as surplus was used a lot due to post war shortages, you could not always buy in new supplies until about the mid 1950's.

 

Indeed it was made illegal to spend over a limit on such hobbyist goods, and if affected layout construction, you were not allowed to buy larger quantities of wood. These restrictions nearly brought the hobby to a close in the 1940's, as did camera restrictions on photographers, and imports of Model Railroad items from the US. The restrictions remained in place for the 40's and were only dropped slowly by the late 1950's.

 

This does help explain the state of models from those austerity years,material were short, and you used what was made or available for other than hobby uses, it was forced on the modeller by the very hard times brought about by the war..

 

Stephen.