16xx Pannier - smaller and .....

[JohnG]

I have trawled through the drawings we are a little closer Drawing number 1260??, lot 215 rings a bell. I will look at work tomorrow, I planned the trip in the lunch breaks and will need to see the email traffic.

You can get the drawing copied, there is a cost and you are allowed for private research, so a scratchbuild would be fine. The drawing contained side elevations, plan views front and back elevations as well. The tanks on 1638 I think have been renewed, as has been mentioned, the radius of the tanks looks a little bigger, there is nothing on the drawing giving a rad, the front plating has also been simplified as it should go around the front tank step.

John.

 

[Overseer]

I have looked at the NRM list again and think I have found the right drawings. The trick was searching for 1600 and Lot 381, instead of 16xx which seems to have been used by the cataloguers to describe untitled early drawings.

I think the useful drawings will be -

Roll Drawing No. Date Title
136 126010 1948/05 Erecting Plan for Lot 381
136 126011 1949/02 General Arrangement for Lot 381
014 126047 1948/07 Arrangement of Smokebox
245 126049 1948/03 Welded Pannier Tanks for 0-6-0T engine - Lot 381

Other drawings which probably aren't so useful are listed as follows
215 126011 1948/02 GA Lot 381 - [Superseded drawing by later version above]
026 B81 1948/05/19 1600 class 0-6-0T Engine diagram
510 128489 nd. Max Cross Section, 1600 class Diag B81
Also some curve diagrams etc.

It looks like a full set of drawings would have been 126010 to 126050 or more. Lot 381 covered numbers 1600 to 1629. There don't seem to be any additional drawings for Lots 389 and 417.

 

[JohnG]

I tried to look at my email traffic unsuccessfully today, I may have deleted it, it was Sept 2015! how time flies.

Without a doubt the drawing is Lot 381, Erecting Plan, dated May 1948, 1260?? That is the one I viewed and took photo's of.

I will keep looking.

John.

 

[Captain Kernow]

I did catch up with 1638 during a flying visit a couple of weeks ago

Thank you very much indeed for posting all these very useful photos. They will no doubt come in very handy when I start my next loco project, which is to build an old Cotswold whitemetal kit in 4mm scale, albeit with a modern (Branchlines/Justin Newitt) etched chassis.

Living close to the South Devon Railway, I've been able to get detailed photos of 57XX and 64XX types, but the K&ESR is just too far away for a casual visit!

 

[Brian McKenzie]

What wheels do people use? Slaters don't seem to do the correct 12 spoke 4' 1 1/2" crank pin between spoke wheels

Fraser,

Had a crack at drawing 16xx wheels - based merely on your photos. If you thought this might be of use, brass castings could be arranged - that you would need to turn and fit tyres.

First iteration shown using : 5-1/2" wide tyres, 9" crank throw. Dimensions can easily be tweaked.



Cheers,
Brian McK.

 

[Overseer]

Brian

That looks good and thanks for the offer. Making and fitting tyres is not a problem (I have metres of suitable steel rod) but I am not sure I want to spend the time on wheels for this loco. This was meant to be a quickish model of a loco I like but it is not really a necessity for any current projects. I will have to think about having some cast, especially having seen the image compared with the flat backed pin-in-line Slaters wheels. Maybe I should turn the Slaters wheels down to S7 and see how they look, or work out an alternative use for them. I won't be able to do anything for the next month as I am lecturing 2 full days a week as well as keeping the rest of my work going.

 

[Overseer]

Fraser,

Had a crack at drawing 16xx wheels - based merely on your photos. If you thought this might be of use, brass castings could be arranged - that you would need to turn and fit tyres.

First iteration shown using : 5-1/2" wide tyres, 9" crank throw. Dimensions can easily be tweaked.

View attachment 100626

Cheers,
Brian McK.

Brian
I think I should take you up on your offer. When I look at the Slaters wheels I know I won't be happy with them on a 16xx, and have thought of another use for them. In fact, I have already turned up the blanks for the tyres for the new wheels. Your rendering already looks better than the 850 class wheels. Sounds like you have a tame lost wax caster, the one I used to use won't do brass any more because it contains lead. They still do bronze but the machinability is variable depending on the mix from ok to tough enough to rapidly wear hss tools. If possible I like to have a central spigot on the back and a little extra thickness on the wheel centre so it can be faced off to a nice smooth surface. I bought a 3d printer in December but haven't had time to get it out of the box yet, hopefully will over Easter, so could print a pattern to cast from to save you the trouble, and find another caster.

This project seems to keep going backwards. I started by buying etches and wheels, and when it eventually gets built it will be nearly totally scratchbuilt. So much for a quick loco!

Fraser

 

[Brian McKenzie]

Fraser,
No problem to add a rear spigot, plus extra thickness to the crank boss, and a machining allowance to the width and diameter of the rim. Bear in mind, the wheel was prepared solely from your photos, so would be pleased to receive any prototype dimensions if available. Being a fussy bu99er, I like to scan in card templates from spoke cross-sections when possible!


I'd also be very interested to see what your 3D printer can output. The tapering oval shape and radial nature of spokes presents a tough test. Fishtailed layers may show if layer thickness can't be minimised. Do check that the type of material you can print is used successfully for the lost wax process, and that your contractor is happy to use it. Some resins will only burn out cleanly on occasions when higher temperature is being used, as for platinum.

For a time, I used Shapeways' New York service for wheels. When I suspected some printed waxes used by Shapeways' casting contractor may have been made coarser than at 16 micron layer thickness (as then offered for the supply of waxes), I reverted to purchasing waxes only - and had the casting done by others. [Shapeways no longer sell waxes on their own, and insist on rumbling all castings - which can round off any crisp edges when they might be desired.] Fortunately, there are now some superior services available from modelling colleagues.

-Brian

 

[JohnG]

Brian
I think I should take you up on your offer. When I look at the Slaters wheels I know I won't be happy with them on a 16xx, and have thought of another use for them. In fact, I have already turned up the blanks for the tyres for the new wheels. Your rendering already looks better than the 850 class wheels. Sounds like you have a tame lost wax caster, the one I used to use won't do brass any more because it contains lead. They still do bronze but the machinability is variable depending on the mix from ok to tough enough to rapidly wear hss tools. If possible I like to have a central spigot on the back and a little extra thickness on the wheel centre so it can be faced off to a nice smooth surface. I bought a 3d printer in December but haven't had time to get it out of the box yet, hopefully will over Easter, so could print a pattern to cast from to save you the trouble, and find another caster.

This project seems to keep going backwards. I started by buying etches and wheels, and when it eventually gets built it will be nearly totally scratchbuilt. So much for a quick loco!

Fraser

Fraser,

If you want to syndicate the costs then I may be up for it also, Like you this is a slow burner, then that is true of most of what I do!, work gets in the way.

regards,

John

 

[Brian McKenzie]

. . . I like to have a central spigot on the back and a little extra thickness on the wheel centre so it can be faced off to a nice smooth surface.

I'll place STL files somewhere where Fraser, and anyone else interested, can download for printing at home or via a bureau. One scaled at an exact 1:43.54 ratio and another increased by 3% as an allowance for possible shrinkage. As I'm never sure just how much resolution STL files should contain relative to the output capability of printers, I'll also provide large and small sized files.

When uploading files to Shapeways in the past, I cranked up the resolution to near their maximum file size of 64mb - and left it to their algorithms to crunch them down. They (at the New York bureau) must also automatically build in any shrinkage allowance necessary for when casting brass, as my work always arrived remarkably true to the dimensions in the submitted files (which meant I received oversized parts when I had incorporated an allowance for shrinkage).

EDIT:
STL files are now freely downloadable from 'Files Anywhere' for the next 30 days.

https://login.filesanywhere.com/fs/v.aspx?v=8c696a885a5f737ab1a3


The two smaller size files should have adequate resolution, but you are welcome to load the larger files to a bureau for your own use. As explained above, one pair of files is enlarged by 3% should an allowance for shrinkage be necessary.
-Brian McK.

[ To check if shrinkage is occurring, the wheel centre diameter, measured over the rim's additional machining allowance is 1.091" at 7mm scale, and 1.125" for 7mm + 3% version. ]

 

[Overseer]

Thank you Brian. Looks good. Now I need to find some time to set up the printer and find some suitable wax resin. Hopefully we can avoid having to make a silicone mould to produce the waxes for casting from, it will save money and increase accuracy.

 

[Overseer]

I have had some motors bought cheaply that I wanted to test out so I have put together a chassis for the 16xx. It is a basic flexichas and uses the Slaters wheels mentioned earlier in this thread at this stage. I wanted to use something from the etchings so have used the side frames, we'll see if anything else can be used. The motor is a Canon, not sure what they were made for but it fits nicely in the firebox. It is quite slow reving at 12 volts so might be 18 or 24 volt. It also starts at less than 1v and has a lot of torque. The gears are Roxey Mouldings 13:1. This combination runs very smoothly and quietly on leads from the controller, and will crawl along on 2v but I think I will swap to the single start worm and 26:1 ratio as I don't need the top speed possible. Coupling rods are scratch built and the horn blocks are Finney. Now the it know it works I can add details.