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Member postings for Dave Wootton

Here is a list of all the postings Dave Wootton has made in our forums. Click on a thread name to jump to the thread.

Thread: Safety Valve
01/02/2021 16:19:18

Hi speedy builder

Jeff is exactly right, I made these to the drawing for a friend, same problem, if you extend the pointy bit down past the contact line they do work, but we did find the re closing was hit and miss. I made some pop valves to replace them, and some for my Simplex to Jim Ewins design which work perfectly, but the pop action is so sudden it makes everyone jump and small children cry!

The Gordon Smith valves are really excellent, Polly models sells the drawings and springs and they are easy to make.

I must admit we didn't persevere or experiment much with the LBSC valve, so could probably have been made to work better if we tried harder.


Thread: Not the only president causing problems.
29/01/2021 17:38:07

img_3986.jpgBit of a milestone today, I think this is the first time the chassis has ever been together and been rolling freely in its chequered history. still a few slight problems to sort out, as the cylinder block is now at the correct height the bogie, which mounts and pivots on the base of the cylinder casting, is now too far down and needs the pivot block trimming, the bogie wheels also foul the frame and needs relieving, the drawing shows this but I missed it so back on the mill!.

Whilst drilling the mounting holes for the cylinder there was a crunch and the drill broke, and there was yet another broken off tap hidden in the cylinder casting, thats three so far previous builder must have spent a fortune on taps!, thank heavens for Mr Dremels invention and cheap diamond burrs. this is about the stage I wanted to get to, got to do a materials order before going further, think I deserve a rest.img_3985.jpg

Edited By Dave Wootton on 29/01/2021 17:42:15

28/01/2021 18:33:26

img_3978.jpgDoesn't look like a lot to show as far as progress, but the cylinders are now together with the cylinder bores and piston valve bores parallel and the correct distance apart, also machined to fit over the frames properly. It took an unbelievably long time to work out where the cylinders had gone wrong, it looks to me as if the cylinders were the point the original builder gave up and the next one took over, the threads change from whitworth to B.A and the workmanship deteriorates drastically. The faces of the block that join together were machined very out of true in all ways, the only reference I could get was the main bores, so I turned up two close fitting arbours and measured everything from there, I had to use a dial gauge and stand like a comparator to measure the out of square, set up on the mill using machinist jacks and shim to skim over the joint faces, also took the opportunity of getting the bores the correct distance apart, for some reason they were .050" too far apart.

The bottom face of the block was built up with brass silver soldered in them, then machined so the block sits in the frames at the correct height and parallel to the centre line of the chassis. the smokebox flange was also miles out, so this was machined off to the smokebox radius using a boring head as a flycutter, the steam ports were cleaned up, as a result of the heating while silver soldering a small piece of broken drill fell out into the hearth, so that was a result. Oil feed ports were drilled into the steam inlet to the piston valves, the steam inlets are at slightly the wrong angle, but decided to leave as they are, the lagging will cover it up. I'm going to use sight feed displacement lubricators on this, following sucess with one on my Rob Roy, on that the glass is reduced to 16mm dia, going to try a 12mm twin set up on this using what would be one of the air tanks as a oil tank, slowly getting somewhere!


Thread: New Hampshire member
27/01/2021 08:10:26

Hi Clay

Welcome to the forum, nothing wrong with buying a lathe on a whim! . I'm sure your background will be a help, after all measuring skills are transferrable, be ideal if you need to make patterns!

There's plenty of expertise on this forum to help you if you get stuck with anything, you might get about fifty different answers to the same question, worth looking through some of the albums on here particularly Jason B for stationary engines, good to have some inspiration. Don't forget to post some pictures.


Thread: Not the only president causing problems.
26/01/2021 17:00:19

img_3977.jpgimg_3975.jpgimg_3974.jpgimg_3973.jpgFew more pictures and a little progress, the pony truck has been a bit of a nightmare, the casting for the rear frame of the engine and the pony truck casting are both a bit off, this has caused much head scratching, the upshot of it all is that the differences have had to be averaged out meaning the pony truck pivot has had to be moved forward slightly, the pony truck axle centres are 1/8" forward from where they should be, but now everything clears, I suppose this is part of the fun of taking on someone elses problems! the rear frame was also twisted slightly so that had to be straighetened and the pads for the truck rollers faced off, never mind all sorted, painted and ready to fit, painting is not my strong point! I built my first engine, steamed it and then had to strip and paint it, never again, so now I paint as I go wherever possible.

I usually use Birchwood Casey gun black for small steel items, but had run out so the little bits are oil blacked, the roller supports are brass and I thought I would try the same makers brass blacking chemical, despite following the instructions to the letter was dissapointed with the result, best I could get was patchy brown.

Next job is the cylinders, initial measurements show the main bores are to size and parallel, however the bores splay apart from each other by .030" ( nearly a V twin!) and the piston valve bores are not parallel with the cylinder bores in any plane!. I'm going to have to do some measuring and thinking about this, the piston valve liners came out with some heating, and the workmanship on those is not inspiring to say the least.img_3971.jpg

Edited By Dave Wootton on 26/01/2021 17:02:24

Thread: Tether car
25/01/2021 07:23:56

Very impressive work Old School, did I imagine it or was there a tether car track in Maidstone, Kent? I remember seeing one when I was quite small in the early sixties and being impressed and quite scared, the speed attained seemed amazing. In one sunday afternoon walk while visiting an aunt I was introduced to noisy model cars and live steam locomotives, funny how things seen as a very young child influence us for the rest of our lives.

Tony, very versatile- live steam, boats and aircraft, keep up the good work.


Thread: Not the only president causing problems.
23/01/2021 17:13:44

Bit more work done on the old thing, not many photo's I'm afraid, but someone emailed and asked if I'd given up!, so thought it was time for a quick update, pony truck being painted at present, will post more pictures as soon as it's reassembled.

Been experimenting with leaf springs which is a frustrating business, after trying leather between the leaves as stated on the drawings, which seems ok on the already made main springs, the leather on those must be around 70 years old and still seems sound, this seemed to stiffen up the spring too much for the pony truck. I remembered some .020" thick PTFE sheet used for some gaskets, and tried using that between the springs, gives a nice smooth action so I'm going to see how that works out in practice. Picture shows finished springs, will have to wait until loco is complete to experiment further, made lot's of spare leaves so can set by trial and much error.


Edited By Dave Wootton on 23/01/2021 17:14:51

Thread: Model boiler safety calculations
20/01/2021 11:44:23

Thank you John for posting the link to the spreadsheet, i'm bumbling my way through re- working the boiler for my 2 1/2" gauge President Washington B&O pacific that I've been posting about. It was designed in 1928 using cast gunmetal throatplate and foundation ring, so needs a little updating. spreadsheet will be a great help.


Thread: Chemically cleaning brass - gently
20/01/2021 08:43:12


I used to run until recently a couple of classic bikes and was plagued with fuel problems caused by the ethanol in petrol attracting moisture. A friend recommended Sta-Bil fuel stabiliser and it does work really well I could leave a bike over the winter and it would start no problem. I did used to run the float chambers empty before putting them away, but still found green corrosion and white deposits in the carbs, the Sta-Bil stopped all that. I got mine via ebay, but i think it's readily available.


Thread: Pennsylvania A3 Switcher
19/01/2021 17:49:11

Lovely work Mark, a pleasure to see, going to be a lovely engine, please keep us up to date on your progress.


Thread: Not the only president causing problems.
18/01/2021 16:50:08

img_3964.jpgThanks Ian, progress slowed up a bit as I had a bit of experimenting to do with making leaf springs, I think I said in the last posting it would be a learning curve, and it certainly was. After lots of messing about with blowlamps, sand baths, tiny tin snips and needle files we finally have a set of leaf springs. I had to anneal my reclaimed spring steel and found the best way was to clamp a little stack of embryo leaves between two bits of 6mm steel, soak at dullish red and leave to cool in the hearth, steel could be drilled, filed and formed quite easily. Hardened and then let down to blue in a little sand bed before quenching in oil. Took a few goes to get right but seems ok and springy. Have made a number of different length spares to enable closer setting when the loco is nearer it's final weight.

Marking out and drilling the lower spring hanger pivot holes took ages as the casting is not symmetrical, The main pivot for the truck has had to be drilled off centre, as the axlebox slots are slightly off, it won't be seen on the finished engine, but if i hadn't done it I had visions of the pony truck crabbing down the track like a B-L Mini with a dodgy rear subframe ( remember those?). Pictures show the first trial assembly , apologies for the bits of welding rods as temporary pins, the little spring retainers were a really fiddly bit of sawing and filing. Still got to make the little straps to go around the springs, next puzzle is to work out the height for the rollers that bear the engines weight on the pony truck, something doesn't add up so a bit of investigation needed there.img_3963.jpg

Thread: 1/2'' scale drawing sources
17/01/2021 09:30:27

Hello Michael

Thank you for posting the link, very interesting, I look forward to investigating the other links on the Chaski forum.

Pleased to see the NYC Hudson picture, I did not realise there where other designs for a Hudson apart from the Miller design, and pleasantly surprised that there is someone producing castings for 2 1/2" gauge. I find the history of the hobby very interesting, comes of having a huge pile of 1930's Model Engineer magazines available to read at school, been on a downward spiral ever since!

Thanks Again


Thread: Not the only president causing problems.
15/01/2021 18:03:12

img_3960.jpgimg_3958.jpgimg_3956.jpgimg_3954.jpgThanks Tom, hope you found it useful.

Bit more progress over last couple of days, bogie has been stripped cleaned and repainted, apart from thinning the wheels to the correct width it required no rectification.This is obviously the work of the original builder, is nicely made and everything works smoothly.

On to the pony truck which was partly made with no provision for suspension, the spring that is visible above the axlebox was just wedged in! pictures show it set up on the mill for machining, this took ages as the casting is quite different to the drawings, so took some figuring out kow best to set it up, the plan was to use the DRO and mill and drill it to co-ordinates, but as the casting is not symmetrical just had to make it as even as possible.

As the rest of the chassis has leaf spring suspension, I'm going to have a go at a pair for the pony truck, I found some spring steel left over from a highly useless set of ebay piston ring compressors that's about the correct thickness, so this should be a interesting learning curve to say the least. It was not intended to start on the bogie/ pony truck yet, but at least it keeps me away from the cylinders which seem to be storing up horrors all of their own. Apologies for the out of sequence pictures, they seem to end up anywhere.img_3946.jpg

14/01/2021 18:04:14

Hi Tom

Thanks, I seem to be making progress although breaking a tap in a finished axlebox slowed things down a bit!

To use the bushes, I measured the centres of the rods as close as I could, using rods in the existing holes (the centre bush is a normal concentric bush) , the difference between the axle centres and the coupling rod centres is the offset required ( say .005" for example).

I turned the outside of the bush as normal to a light push fit in the hole in the connecting rodl, but before drilling and boring it out I removed the bar from the 3 jaw chuck, placed a .005" shim under one of the jaws, centre drilled , drilled , bored and reamed to size. I also made a slight mark on the bush next to the jaw with the shim under it, this is obviously the thin side of the eccentric bush, and parted off. If the rod is too long the mark would go on the inside to shorten the centre distance, and the mark on the outside if too short to lengthen the centres.

After fitting and checking I used some wicking grade loctite ( 290 I think) to hold it in place, although this is really screwlock it is very strong and finds its way through tiny gaps. None of the above is particularly good engineering, but it does work.

I'm ashamed to say my first loco Rob Roy had to have this treatment and as I had no really accurate equipment to measure the error, I made the eccentric bush slightly more eccentric (!) than I thought it needed and turned it untill everything rotated smoothly, then loctited it in, absolute heresy I know but it's still going nearly forty years later!

Hope I've made the above clear, I'm better at bodging than writing, any questions please ask.



Edited By Dave Wootton on 14/01/2021 18:04:46

13/01/2021 17:23:40

img_3949.jpgimg_3944.jpgimg_3943.jpgBit more progress on President Washington chassis, Coupling rods, cleaned up, bushed and fitted , i'm afraid I had to use eccentric bushes to get the centres correct, whoever made these got them all over the place, one side was .017" too long and the other side .008" too short. I know i should have bored them to the correct centres, but the nickel silver rods were very thin around the bushes and I didn't want to weaken it any further.

While fitting it all back together I noticed there was little room for the brake hangers, after a bit of puzzling I realised the wheels were over width by about .050", I checked the diameters but not the width, goes to show trust nothing. I had to machine the wheel faces off by holding the finished wheel sets between centres, the cast iron is horrible to machine, maybe the reason they were left oversize as the original builder probably didn't have carbide tools to work with. On checking the bogie and pony truck wheels were also oversize on the width, so out of the intended sequence I had to face these off as well, I like to strip the lathe and clean it out after a cast iron session, so this saved me doing it twice.

Pictures show the rods assembled on the chassis, it all turns nicely now, The bogie is very nicely made, presumably by the original builder, with a nice little leaf spring and everything well fitted and working well, just needs painting while apart. Hopefully pictures below will be self explanatory. Will post more as things progress.img_3942.jpg

13/01/2021 17:02:58

Hi Tony

Nice to see 2 1/2" gauge builders on the site, Black 5 is a lovely engine, keep them coming!


13/01/2021 09:44:56

Hi Ian

Thanks, I have been visiting the site ever since I got the chassis, i'm pleased to see the loco is now under cover, at one time it was in the open looking very sorry for itself.

Should have the coupling rods finished today, and I'll post some more pictures.


Thread: Juliet no 2
12/01/2021 20:54:00

Thanks for posting Tony , Is the Baker valve gear an option on LBSC's design or your own application? I've seen Juliets with various valve gears, I'm sure a friend had one with slip eccentrics, or maybe stephensons, memory going!


Thread: 3.5 gauge Juliet no.2
12/01/2021 20:47:45

Nice work- almost there! thanks for posting a pleasure to see.


Thread: Not the only president causing problems.
12/01/2021 14:24:44



Thanks I'm hoping to encourage others to post, if I can do it anyone can! I think it was Dobwalls that sparked my interest in American ( and Canadian ) railroads, it was a great day out, the kids never moaned all day!


It was drilled like that! not sure what went on but the brackets and expansion links are very well made by the original builder, but Mr Hamfisted one of the later builders seems to have fitted them carelessly, it was easily put right with some brass silver soldered on and redrilled, it now all lines up.

Interesting that the design was also marketed in Canada, I'm pleased that there is at least one running still, the drawings are good, obviously things like the boiler design is of it's time, with cast gunmetal throatplate and foundation ring, I'm attempting to redraw the boiler up to acceptable standards, which is a slow process for me( I can't do CAD, there's lots of rubbing out going on!)


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