96RAF Posted December 31, 2018 Share Posted December 31, 2018 You never do anything without a good reason Ken.Nice to see you knocking these new problems on the head one by one like wack-a-mole.Rob Link to comment Share on other sites More sharing options...
Go_West Posted December 31, 2018 Author Share Posted December 31, 2018 Hi Robi do wonder about spare parts like the posting on the forum conservation of part is a must as you point out and if it's possible to remake parts then that should be the way to go but I see a time when maybe servicing one engine from other parts might be the only way to go for some maybe like 3D printers more home based CNC machines will come small volumes from big companies incur high cost the one part hard to make or replace is the electric motor there maybe a suitable replacement but must be plastic free in construction as the heat in this area is very high after a few runs.Ken Link to comment Share on other sites More sharing options...
96RAF Posted December 31, 2018 Share Posted December 31, 2018 Not in my lifetime Ken, but I can see the universal household maker-bot providing everything folk will ever need In days to come.Meanwhile hoard your spares.Rob Link to comment Share on other sites More sharing options...
Go_West Posted January 1, 2019 Author Share Posted January 1, 2019 rob not mine ether.moving on.The wheels, I’m hoping to fit the Hornby wheels as they are which means I will not be making new centres with square holes the only ones that will have the new centres will be the wheels with the connecting rods from the cylinders this is because these wheel have to be in perfect timing with the valve events.Here is a drawing showing what is needed./media/tinymce_upload/e045ea451bb7c50e9bd5a7074c6c92d5.jpgLooking at the drawing it gives an idea as to add the square centre in the wheel this idea is standard on all Hornby live steam engines and its this square centre that needs to made up first. The picture shows a standard needle file but it has an area ground away removing the teeth and producing a smaller area than that in front of it. The idea is to produce a broach tool that will cut a square the right size for the square Hornby axle./media/tinymce_upload/b19949d4b59154fe8240fcf0a255a88a.jpgFirst we need a section of brass to make the centre out of so some 6 mm brass rod was put in the lathe and turned to a diameter large than the finished diameter to allow for the square hole not being in the centre of the brass so that it can be trued up later./media/tinymce_upload/85787e1592fcd51add7e8ef6867cce97.jpgThis is the brass rod being turned to just over 4 mm /media/tinymce_upload/05178b74381e9e6160c83e9634f29fcb.jpgNow it needs a hole drilled into it which wants to be smaller than the finished square hole./media/tinymce_upload/8250a0513bbfc9b8315c80daa6e27ab8.jpgNext is to part off the small brass ring but maybe a little thicker than is needed for the wheel hub this way we can remove some metal to give a flat surface and the right length./media/tinymce_upload/14085b31dfcb5a8726864437d0bd3535.jpgNow a small amount of filing in the drilled just to generate the start of the square.This will help stop the brass ring from cracking.Once you are happy with the almost square hole push the file into the brass ring once more and this time knock the file through the brass ring with a hammer. Remove the ring from the file and turn the file 90 degrees and knock it through again do this a couple of time and with luck you should have a square with parallel sides./media/tinymce_upload/51c197683db60bd5f39ee1ed35bcda7c.jpgIt should be a good tight fit on the square of the axle and to get it to fit right home might need a tap with a hammer.Now it axle can be put in the lathe and the outside turned down to 4 mm this will make sure that the brass centre is running true./media/tinymce_upload/2b267df447642469fca8203df48a0226.jpgOnce you are happy with the brass centre and its running true its time to put some threads on it so it can be screwed into the wheel./media/tinymce_upload/690f8d6e4ca26cdffaa782bfbda42e08.jpgThis is the finished wheel centre all that is needed is to screw it into the wheel but we need to mod the wheels first to take this new centre.You can buy wheels that are metal which come with square holes in but I have found that these fall apart after a time due to the heat and the oil and the only way to make sure they stay together is to drill and pin the tyres to the wheels.So on this engine I have bought some Hornby wheels and will start on the wheels now. When I say I bought some Hornby wheels I have in fact 2 sets of wheels one set has a white painted line around the rim and hub axle centre the other has not. may be someone can tell me why that is ?/media/tinymce_upload/a32c2371a48c67f58656c14c39fcdde8.JPGIt might not be clear in the picture here but the wheel on the right has the white painted linesAs I think the white line wheels will be used I shall try out the mod idea on the unpainted wheels first just to check this is going to work./media/tinymce_upload/3e03e7969fd8f38dbc67ea72f70dfff5.JPGThe first job is to remove the protruding centre boss from the back of the wheel this is a straight forward turning job. /media/tinymce_upload/a44a8fe12d2b1b07534c913659c73acb.jpgOnce this is done the next part is to bore out the centre of the wheel to 3 mm with a reamer/media/tinymce_upload/cf58550e61c85e4180b3b3aeeb7be1f0.jpgThen it can be taped 5/32 x 40 but not right through the wheel only to about half way in./media/tinymce_upload/63b28519f7b9c0d1bc5ccacf992a51a4.jpgWith the axle and the brass centre held in the tail stock chuck the brass centre can be pushed up to the wheel and by turning the lathe chuck by hand you can screw the centre into the wheel a good idea is to add some locktite before you screw it into the wheel this way it will give you time to set up one of the flat sides of the square to a line with the crank pin as that the quartering will be correct when the wheels sets are fitted to the chassis./media/tinymce_upload/ef9a84da7bfe70c4e8fecd82fd44844e.jpgThe brass centre wants to be a little higher than the outer wheel rim this way using some wet/dry the back of the wheel can be trued up so the wheel will run true./media/tinymce_upload/11ade892d4812c3243e227369ef02269.jpgThe wheels in place and the valve gear complete some connecting rods from the kit and I might be able to get the wheels spinning. 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walkingthedog Posted January 1, 2019 Share Posted January 1, 2019 The square hole looks way off centre or is that just an illusion? Link to comment Share on other sites More sharing options...
2e0dtoeric Posted January 1, 2019 Share Posted January 1, 2019 No, the brass? crank-pin bush is! It appears to be offset anti-clock by a couple of milli's. Look at the spacing from the three spokes adjacent.Maybe it is supposed to be, I don't know. Link to comment Share on other sites More sharing options...
Go_West Posted January 1, 2019 Author Share Posted January 1, 2019 WTDJust checked by fitting the wheel on the axle which is on the chassis and spun the wheel looks fine might be the way the thread has come out on the brass centre as the start of the first cut thread compared with the full thread opposite is what is making it look off centre.with a bit of luck today I hope to get the engine running on compressed air and that will show how good these wheels are.Ken Link to comment Share on other sites More sharing options...
walkingthedog Posted January 1, 2019 Share Posted January 1, 2019 I’m sure all is well. Look forward to seeing how it runs. Link to comment Share on other sites More sharing options...
Go_West Posted January 1, 2019 Author Share Posted January 1, 2019 WTD and Ericmhave now took some video and it looks to be ok the only wobble is the axle in the bearings as this is a week point with Live Steam and to over come this i have fitted ball race type bearing so now a look at the work fitting the con rods and then the video./media/tinymce_upload/d218eef498ee3df2ccc04f524010a138.JPGThe connecting rods from the kit came in 2 parts and are soldered together therefore making a thicker section.The only thing is was the hole centres on the these connecting rods going to be right for my model as most of the cylinder and wheel positioning was by guess work.After the soldering of these 2 rods the holes were drilled in place and offered up to the engine and they fitted perfectly./media/tinymce_upload/fb9bf1ee6de6cf48361371727154fe9e.jpgIn the picture here the engine is running on compressed air so good to see after all the work so far but still much to do and until all the wheels are on and the engine is run on the track I still have a big question mark hanging over this project.At the same time I was taking the video of the engine running the film the Railway Children was on the TV years ago when the children were small we walked the railway and rode the trains we did this several times a great little railway.Ken Link to comment Share on other sites More sharing options...
Go_West Posted January 1, 2019 Author Share Posted January 1, 2019 goes like a fidders elbow Link to comment Share on other sites More sharing options...
walkingthedog Posted January 1, 2019 Share Posted January 1, 2019 Obviously the wheel centres are spot on, looks fantastic. Link to comment Share on other sites More sharing options...
96RAF Posted January 1, 2019 Share Posted January 1, 2019 I like that...I wonder if the crank pin boss angular offset is for forward thrust strength within the wheel spoke geometry.Rob Link to comment Share on other sites More sharing options...
Go_West Posted January 2, 2019 Author Share Posted January 2, 2019 Crank pinor is it so that the pin is a standard Hornby item and on an engine with conventional valve gear the valve drive connection moves the valve gear rods back and forward.but on a P2 Hornby engine it has poppet valve a a rotating drive shafts so the crank link needs its out end to run dead centree to the axle so the small gear box will not be going back and forth So by making the plastic wheel have an off the centre look the crank pin boss end with its 2 machined flats for the drive crank to fit to with its small hex screw and this assembly will now run true a bit like a speedo drive crank.i hope this make sense but until I get to assemble the valve drive i will not know.Ken Link to comment Share on other sites More sharing options...
Go_West Posted January 6, 2019 Author Share Posted January 6, 2019 /media/tinymce_upload/6dcb527a79c7538a0802d9a663591434.jpgThe connecting rod were bought as spares for the Hornby P2 so would be easier to fit to the Hornby wheels that I was going to use.The only problem with these connecting rods is they are made from very thin brass sheet and as these engines deliver a lot of power to the crank pins it was thought that excessive wear will take place on the crank pins and rods./media/tinymce_upload/0adcafd0aef5aa9ddf718f5112ff7f29.jpgTo over come this problem an idea to beef up these rods was undertaken.New bronze bearings were made and soldered to the rods along with strips of brass to be soldered in-between the bearings on the back of the rods this then made the complete assembly a much stronger looking job./media/tinymce_upload/a0b3f6aefc280e8d3e39481a53dbc973.jpgBack to the Hornby chassis now with 6 drivers fitted and the rods also in place now for the last set of drivers The Hornby chassis was not long enough to incorporate these wheels so an extension was needed./media/tinymce_upload/1ec72772b7c20d62686904b40e798ad9.jpgIt was decided to fit the rear section of the chassis from the kit by cutting this chassis between the last 2 wheel sets would also give the flared frame section for the last 2 wheels under the cab.I might have to mill off some of the metal of the Hornby chassis to get this sheet section of chassis to fit nicely. Once this was completed the kit part can be held in place by screws and maybe I could start to build up the engine once more and test it all out on compressed air and run in these new rods and bearings./media/tinymce_upload/49119b2cd05ff9644084aca2b6cb387b.jpgThe chassis had both sides milled out to take the frame extension which is in the picture above The next part will be to find a way to fix these two sections together and where to put the screws so that the wheels will not rub on the screw heads and short out the power./media/tinymce_upload/8041dd6d9d8eb6d0936a32670487429b.jpg I’m not sure how this engine is going to run on my track and if the last set of drivers should be sprung ? And also if a pair of the drivers will need rubber tyres for more grip but at this stage it’s a game just getting all the wheels to turn with out jamming up due to the new bearings.The front bogie wheels are articulated so I’m hoping these will not be a problem but the wheels under the cab will need some thought as they are not the standard pony truck type and it looks like the Hornby model of the P2 has the flange removed from these wheels to help with tight curves so some testing in this area will have to be carried out and see what happens. Link to comment Share on other sites More sharing options...
2e0dtoeric Posted January 6, 2019 Share Posted January 6, 2019 Most of the manufacturers leave the flanges off the Cartazzi truck, for that reason. they often supply flanged wheels for display use. Link to comment Share on other sites More sharing options...
Go_West Posted January 6, 2019 Author Share Posted January 6, 2019 Ericmthanks for the information will find some wheels in my wheel box and if I can't get them to track up will turn off the flange must look up Cartazzi Link to comment Share on other sites More sharing options...
Go_West Posted January 6, 2019 Author Share Posted January 6, 2019 Found this on the forum/skin/frontend/gene/default/forum/images/default_avatar.jpgWobblinwheel1312 postsWhat are your opinions on the so-called "Cartazzi trucks" on these Hornby Pacifics? My very first opinion of this design, with the flangeless wheels, was completely ridiculous and unacceptable. Watching the rear "bogies?" completely leave the rails, stop turning, and hover in mid-air around curves, just simply looks idiotic to me! To build such highly-detailed models that look so WRONG going around curves, well, the logic behind the design eludes me. I have managed to modify my two A4's by cutting-out the plastic vertical "ridges" inside the truck frame, and Dremelling out a concave relief so the wheels can slide all the way against the metal chassis. Also installing flanged wheels, of course! This allows the wheels to slide FULLY to the outside (against the plastic outer frame), and to the INSIDE (flat against the metal chassis). I have also installed, above the axle, a small coil spring (by drilling a shallow relief hole to hold it there) in order to exert slight downward pressure on the wheels. I have found this to work perfectly. Even around relatively sharp curves AND points! I have since found out, on one loco, that small plastic "shims" over the axles will work instead of springs, to keep the wheels from "riding-up" off the rails. It still seems to me a PIVOTING truck would've been a much better idea! What do you think? Don't you think loco wheels "hovering" in mid-air looks a little STUPID?? Especially since they're not even TURNING! Since they are SPOKED wheels, this is painfully obvious.....Posted at 16:32:58 Wed, 21 Jan 2015Edited at 16:36:50 Wed, 21 Jan 2015Approved/Moved at 16:36:50 Wed, 21 Jan 2015 (Reply to this TopicM. CraftonfReport Link to comment Share on other sites More sharing options...
Go_West Posted January 6, 2019 Author Share Posted January 6, 2019 Just thought I would show you this as I have now got it running with all the wheels going on compressed air at 20 psi /media/tinymce_upload/54d7956004f5ca3d9bf54ed2b4f2d99f.JPG Link to comment Share on other sites More sharing options...
walkingthedog Posted January 6, 2019 Share Posted January 6, 2019 Looks good Gowest. I had a couple of pacifics with the fixed truck and flangeless wheels but got rid of them because they looked daft on curves. I know they are more 'realistic' but I don’t think this sort of realism is necessary on a rtr model loco. Link to comment Share on other sites More sharing options...
Go_West Posted January 8, 2019 Author Share Posted January 8, 2019 WTDYou are right about how much detail is needed,when running my Hornby electric very high detailed engines bits fall off from to time but maybe that's just me Link to comment Share on other sites More sharing options...
atom3624 Posted January 13, 2019 Share Posted January 13, 2019 That looks fantastic - and excellent selection of locomotive.Can't wait to see the next updates!! Al. Link to comment Share on other sites More sharing options...
Fishmanoz Posted January 13, 2019 Share Posted January 13, 2019 Wow gowest, 20psi and it seems to have lifted right off the track and is flying! Can’t wait to see steam-driven on approach to Gatwick. Make sure you file a flight plan though or you may get shot down given recent events. Sorry, couldn’t help myself. Waiting to see future progress though. Link to comment Share on other sites More sharing options...
Go_West Posted January 14, 2019 Author Share Posted January 14, 2019 Fishmanozoyes it ran well on compressed air but when I tried it on the track in steam it was very poor not starting on its own with out a push and then only went 2 ft and stopped it did run a little better backwards but ran out of steam very quickly so after all that work a complete failur.one of the problems is all the chassis that I'm using now are none runners that I bought some years ago and have problems before I start the mods.i have spent at least 3 days trying to find out what the problem is with this engine and have gone through every part taking it to bits and inspecting ever part. In the end I cam to the conclusion that the valve assembly was worn to the point that when hot it was acting differently from when cold and running on compressed air all looked fine. I think Hornby did find a problem with this part and on later models chrome plated it which while a good idea for the rotating valve and stopped any wear to the valve port faces not so good on the valve shaft as this is stainless steel which is a mixture of chrome and steel means you are now running 2 metals of the same type against each other which will cause them to wear out faster and if poor oiling is added to the equation it life becomes even shorter.i have toyed with the idea to re engineer this part and make it a lititle better but getting back to the engine I decided that I would replace the valve assemble which would need machining it as the valve unit is a none standard part now for this engine plus change the cylinder assembly so a major rebuild along with making up new connecting rods.all this work was carried out and after a few runs in steam it has run much better there are still problems like the main drivers are slipping which is bad as this uses up the steam fast and leaves the engine out of steam at some point and the engine sits there while the pressure builds up then it's off again with wheels spinning till it reaches the same point again and stops due to lack of steam./media/tinymce_upload/5205151ee55c5c6a8cc440d463eda897.JPGThis is the old part remove and a new one made so now the question arises which wheels need rubber tyres and will have to remove them from the engine and machine some grooves in the metal tyresi did get the from bogies to run ok so at least one thing went with out a hitch but as to the set under the cab lots of problems there using flanged wheels has presented a problem and I see why Hornby opted for flangeless wheels floating above the track.so still lots to do which is Nearly all rework to get the engine to run properly plus still working on making the outside valve gear rotate Now your up to date Ken Link to comment Share on other sites More sharing options...
walkingthedog Posted January 14, 2019 Share Posted January 14, 2019 I’m amazed by your patience. Link to comment Share on other sites More sharing options...
Go_West Posted January 14, 2019 Author Share Posted January 14, 2019 WTDAs a much younger man I might have given up on this one but I do like odd looking engines so must give this one more try ken Link to comment Share on other sites More sharing options...
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