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Not the only president causing problems.

Rebuilding a part completed pacific.

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Dave Wootton12/01/2021 12:37:38
112 forum posts
24 photos

img_3939.jpgimg_3941.jpgimg_3940.jpgPresident RodsHaving just seen a request for more model pictures to be posted, and as I always like to see others build logs on the forum, here's my attempt.

The loco is a 2 1/2" gauge B&O RR Class P7 " President Washington" that has been partly built to the design of H.J Coventry of the USA in 1928, castings were available in the UK from George Kennion in the very early thirties.I bought the chassis from a fellow 2 1/2" gauge Association member some years ago after seeing it at a rally and pestering him a bit! He had bought it some years before on ebay but had not had time to work on it. The original builder did a good job, but others have had a go over the years and undone his good work., whoever quartered the wheels and made the coupling rods got everything wrong then proceeded to file bits off in order to try and get the wheels to go round, the result being sloppy axleboxes and wheels pointing in all directions.

So far I've remachined the horn slots in the cast gunmetal frames, made new axleboxes, bored on the faceplate in a little fixture to keep them all the same, axles, crankpins. Sorted out the expansion link bracket, as can be seen the trunnion bushes were a little out!. The wheels have been quartered, and at the moment I'm sorting out the cast nickel silver coupling rods, I'll post some oictures of those when they are finished.

The idea is to get the engine completed to be steamable, repairing and conserving as many of the original parts as possible, it is a long term project, I only started it as I can't get on with the boiler for my Crab loco at the moment, but I will update as i hopefully make some progress.President washington

I don't seem to have much control over where the pictures go, so they are all a bit out of sequence, but I'm sure you can work out whst they are!

Dave

br12/01/2021 12:47:58
221 forum posts
1 photos

Good for you and thanks for posting . Title put a smile on my face

On the USA theme, Dobwalls had a magnificent 7.25 inch Big Boy some years ago

Now down in Oz,I believe.

br

PS Keep them coming please.

Jeff Dayman12/01/2021 14:00:02
1974 forum posts
45 photos

Hi Dave, the engine's looking good! Was the valvegear hanger bracket shown with the rod through it bent somehow, or did someone drill it at the wonky angle?

Not easy sorting out old bodgery if those who went before did it with size 14 boots..... Thanks for the pics they were great to see. There are a number of these President models local to me here in Canada as the casting sets were sold at one time by Miniature Power Products in Woodstock Ontario. If I'm not mistaken Ted McJannett still runs one at GHLS in Hamilton Ontario.

Dave Wootton12/01/2021 14:24:44
112 forum posts
24 photos

Hi

br

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!

Jeff

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!)

Dave

IanT12/01/2021 14:38:16
1749 forum posts
164 photos

Always good to see a 2.5" engine getting restored Dave. I'm sure you've already found this but the B&O Museum has this reference:

B&O Museum - No 5300

No 5300 Photos

Regards,

IanT

Dave Wootton13/01/2021 09:44:56
112 forum posts
24 photos

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.

Dave

Tony Wright 113/01/2021 10:33:16
avatar
92 forum posts
37 photos

Looking great .A fellow 2 1/2 gauge builder . So far built Martin Evans. Black 5 (only 7 years to build !) Eagle,and an LBSC design F4 . Just about to embark on another 2 1/2 once the Juliet is finished!

best regards Tony.

Dave Wootton13/01/2021 17:02:58
112 forum posts
24 photos

Hi Tony

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

Dave

Dave Wootton13/01/2021 17:23:40
112 forum posts
24 photos

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

Tomfilery14/01/2021 09:42:54
127 forum posts
4 photos

Dave,

That's looking great!

How did you use the eccentric bushes, to correct the misdrilled coupling rod spacing? I can see how they would work, but was wondering how you adjusted them. Do they have spanner flats behind the rods, or did you install the bushes and then drill them to suit the crankpin spacing?

Regards Tom

Dave Wootton14/01/2021 18:04:14
112 forum posts
24 photos

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.

Dave

 

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

Tomfilery15/01/2021 09:45:57
127 forum posts
4 photos

Dave,

Many thanks for taking the time to respond. Yes, that is all perfectly clear - thank you. I had thought that was probably how you did it.

I asked for clarification because I'd seen previous references to using eccentric bushes, with the implication that they allowed some degree of adjustment when fitting. I could see how being able to turn a bush in the rod, before final fixing, might allow a little adjustment, but couldn't see how you could avoid also introducing unwanted adjustment in the vertical direction as well as the horizontal.

Please keep up the good work and continue posting.

Regards Tom

Dave Wootton15/01/2021 18:03:12
112 forum posts
24 photos

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

IanT15/01/2021 19:59:28
1749 forum posts
164 photos

Coming along Dave

Regards,

IanT

Dave Wootton18/01/2021 16:50:08
112 forum posts
24 photos

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

IanT18/01/2021 17:19:53
1749 forum posts
164 photos

Made a mental note of the spring tempering method Dave, will try it when the time comes - good idea, thank you.

Lovely casting for the pony truck too.

Regards,

IanT

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