Foden7536

.

Thanks for Sharing, this is the Thornycroft which is subject to a restoration thread on here started by Tomo Thompson until he sadly passed away. If I was clever I’d work out how to post a link to his blog!

Good morning, Ive attached a couple of images of my Foden laying out of use and it clearly shows these sheets. In the rear of my cab there are two 1/2” holes where I assume these “curtain rails” ran, the front canopy cross member has been replaced in the past so this detail has been lost, but I intend to put these back when I am at that stage of my restoration (which reminds me I really must do an update) The close up image of my wagon appears to show the rail running horizontally, and you can see the sheets hung over it at the rear. Hope these are of interest. David

What a super photo, thank you for sharing. The wagon nearest the camera is a 5 ton Foden, whilst I would say the one further away is a Clayton. The foden is similar to mine, albeit mine has (or at least should should have) a tipping body, whilst the one in the photo isn’t a tipper interestingly the Clayton has Bauly wood block wheels, but what is more intersting to me personally is how the Foden’s sheets have been pulled back against the front of the cab, I have a photo of my foden during its Devon County Council days with the sheets tied back in this manner and I assumed this was a “Devon CC thing” but seeing this makes me think that I was wrong! Thank you for posting David

You’re not hijacking it at all, it’s all interesting and relevant stuff, thank you for the information David

Thank you for those thoughts Andy, The correct dovetail cutter was available off the shelf from MSC, so tooling wise this wasn’t an issue. The original keyways weren’t at exactly 90 degrees to each other, the advantage of getting it done at Inca was the crank sits easily within there machines capabilities and with the modern electronic dividing head the keyways could be cut more accurately, not a second out from 90 degrees, this has meant that the gear blank (the keyway slots in which I had wire eroded) can be accurately made and fits in any of the four possible positions. Working on a friends Burrell Traction Engine we found that the keyways aren’t very accurate and the gear only fitted in one position, each keyway having been scraped and blued to fit - I guess this was when being “a fitter” as a skilled job.

Good evening, thank you for your kind remarks. I am only a hobby machinist with a workshop in the garage, for “real work” I am a central heating engineer, I have friends who offer me advice and guidance but I basically make it up as I go, and as the scrap bin would testify things rarely go right first time!!! The keyways and keys are outside my machine, and personal capabilities. They are dovetailed into the crank, these were very worn and working within the dovetails, a local(ish) firm (Inca Geometric in Charing - near Canterbury) recut the keyways for me on their massive CNC mill, the keys were then made by a friend (Paul Smith Engineering at Gaza, Sevenoaks Weald) they are ground - and I don’t have a surface grinder - nor the experience of using one! There is a gear cluster carrying the two crankshaft gears which slide along these keys for high and low speed, as well as “out of gear” this needs replacing as now the crank has been ground it’s too loose on the shaft (the old was beyond saving as it was very worn in the keyways too) I am going to have new gears cut, but before I can get these I need to sort the second shaft so I can measure the gear centres etc (I also need to save some more money as they’re not going to be cheap!) I hope these photos illustrate the key arrangement David

Good evening all, just to confirm I haven’t dropped off the planet, Foden work progresses but everything seams to take such a long time! So, back in September 2020 (crikey) I stripped the crank and found it was in need of major work, this is now complete and so I thought it was an opportunity to update this. As the old main bearings were very worn I needed to ensure the alignment of the crankshaft was correct, I made aluminium blanks to go in the cylinder bores, the neck rings and the trunk guides, all with a 1” hole bored in the middle, so if all three lined up and I could feed a bit of inch bar through the holes it would prove the centre line of the piston / piston rods. The below photos show this set up for the high pressure, I did the same for both bores. Once this was done I could put another piece of bar at 90 degrees to these rods, to set the position of the crankshaft, however when this was in place it didn’t look correct, this “crankshaft” was too high in relation to the old main bearings which I had put in place to give me an idea of the set up. I spoke to several people involved in Traction Engine restoration work, and the opinion of them was that the centre line of the crank should be bang on centre line of the pistons. When measured mine had a difference of 3/8”, being below centre line, again I spoke to several people who all said that this is incorrect, and I started looking into correcting this “mistake”. I am in contact with a chap in Australia with a couple of Fodens and I was explaining this to him, and he kindly did some measuring on one of his Fodens and again found the centre line of the crank to be exactly 3/8” below centre line of the bores, his foden being a lot later than mine suggested that this wasn’t an error after all. After doing more research I found that this is called “desaxe offset” (desaxe meaning “unbalanced” in French) so there isn’t a true “top dead centre” so to cut a long story short(er) I kept the crankshaft 3/8” below centre line of the bores, and more alumnium billets bored to take my “alignment rods” (a snug push fit) to hold everything in position. Having set and finalised the position of the crankshaft centre position I decided to line bore the newly cast bearings, however I had never done any line boring, and hadn’t a line boring set up, so my next task was to build a line boring machine. I had seen these in use before but I didn’t like the feed method on others, some use a ratchet type feed, which I felt would give an interrupted cut. It was whilst using my mill that I came up with the plan of using a align power feed unit as this is variable speed, does forward and reverse, as well as rapid traverse, so a unit was purchased, I then made myself a lead screw, boring bar etc. To power the cutting tool rotation I used a variable speed drill. The actual boring bar was initially run in two bearing blocks, each held on plates attached to the boiler hornplates, however I found that I was getting too much “whip” on the bar and a poor surface finish so I ended up having to put a third bearing in the middle to keep everything rigid. IMG_9289.MOV I experimented with speeds and feeds until I was happy with the finish, and considering this is all home made I was very pleased with how it was progressing…. …. so well in fact that one Tuesday having a day off from work I was on the final cuts on the second bearing, it was a slow process with lots of measuring, boring, measuring, boring etc but I was aware that I was getting nearer and nearer to size. My final measuring revealed that I had 0.015” to come out, so I moved the tool but in my haste and excitement to finish the job I forgot that I had measured the diameter and I needed to move the tool by half the amount…. I realised my mistake when it was about half way through the bearing, and sure enough to my horror when I measured the bore I had taken too much material out, so I had no option but to go back to the foundry, get another bearing cast (and big lumps of bronze cost!) and start that bearing all over again! I’ve kept the scrap bearing on the wall in the shed to remind myself to double check !!! Once these were finished I could drop the crank in with more aluminium pieces to ensure the “left / right” position of the crank was correct, spacers made, and the sides of the bearings faced to give clearance. With the main bearings eventually finished my attention turned to the bearing caps. These are cast iron, but one has been replaced with a fabricated one, so I decided to replace them both with new cast iron ones. Once again my friend Roger made me a pattern and I undertook the machiningA quick coat of “service colour” and finally this evening the crank was dropped into the crank pit hopefully for the final time! It was very encouraging to be able to turn the crank and everything rotate nice and freely, so hopefully it’s not too far off being somewhere near correct. I hope this update has been of some interest.

Good evening Clive, and May I say what a thrilling message to get! I’d love to see any photos of the Devon CC wagons, and likewise and other details you may recall from your Grandfather. I have sent you a private message, if you can’t access it for any reason please let me know. I look forward to hearing more, any information which can put the history of the wagons ive attached two photos of Devon wagons I have, the first is a Garrett with the early “Devon County Council Northern Div” lettering (and in small script you can just make out what looks like “...Stone Surveyor” - which you’ve filled in some information on already!) and the second photo is a later Foden 10530 of 1921 painted in the later livery of “Devon County Council” as according to my records Northern and Southern (Barnstable and Tavistock offices) combined in 1921 so vehicles after this date carried this lettering. Hope this is of interest, David

Good morning Peter, Happy new year too! The copper tube i used was the same OD as 1/2” steel tube (.0825”) so could take a BSP thread, I had one length of this, but now I’ve only been able to find thick wall copper tube which is 1/8” wall, so the OD is 0.75” so sadly not large enough to take a thread. Your comment on refrigeration grade copper is interesting, do you know what wall thickness this is? I've attached two photos, the first shows an original Foden feed water heater coil from a albeit slightly later wagon removed from a corroded casing during restoration of a friends Foden, and my newly manufactured version... David

Thanks Steve, Work on the Foden hadn’t stopped - just my reporting had! I shall Endeavour to do better with keeping it updated The copper came out so much better than I was expecting I was amazed myself to be honest! At a friends farm we have a huge radial arm drill, I borrowed the table (a stonking great lump of cast steel weighing god knows how much but several hundredweight) as I know this would give me a stable bench to work from, and plonked it in the middle of the shed as I would be walking round it all day bending the pipe. To the bench I clamped (using the T slots in the base) a piece of plate to which I had welded a piece of steel pipe of the right outer diameter to suit the internal diameter of the coil (this was sticking upwards) This plate had a hole in for the end of the pipe to stick down through and a second piece of pipe welded at 90 degrees to the vertical piece of pipe to pull the first bend over (where the feed water pipe comes into the heater straight and then turns to start to form the first coil. Is this making sense so far, I appreciate my description isn’t the clearest? Using a large propane / oxygen heating gun I got a section of pipe about 18” long cherry red and then immediately dunked it in a barrel of cold water to anneal that section of pipe, then placed it in my jig and with the amount of leverage I had in the three meter length of pipe it bent really easily, but I also used a hide mallet to GENTLY tap the pipe around the former, You could feel it getting harder to bend so it was then a case of removing the pipe from the jig, heat and quench (overlapping the previously annealed bit) Place back onto the jig and bend the next bit. Once I had done all the coils I welded about piece of pipe to the vertical one to pull the “exit bend” to get things straight again. This was the most fiddly part as I had to weld it strongly enough as not to break off when forming the copper around it, whilst at the same time only having small welds to access and grind off before I could slide the copper coil up and off the former. The whole operation took a day (not forgetting mandatory tea breaks!) I had done some trials before, and had been advised to fill it with sand etc first, but I found this unnecessary. I was really pleased (and surprised to be honest) with how well and easily it all went, so much so that I was too busy doing it to think about taking any photos. Did you manage to make head or tail of my description? David

So another project I’ve worked on this last year is the manufacture of the feed water heater, again for the benifit of non steam readers - most wagons, and some traction engine makers (especially Marshall as I’m sure Hedd will correct me on if I’m wrong!?) fitted feed water heaters to use exhaust steam to pre-heat boiler feed water to help improve efficiency. This takes an amount of exhaust steam from the blast pipe (exhaust pipe) and is fed into a cylindrical casing through which a coil of copper pipe carrying boiler feed water passes, thus heating this feed water. The exhaust steam (now condensed back into water) is then drained into the ashpan. The feed water heater, and associated pipework was completely missing from my Foden when it came back from the US (when it was removed, be it during its working life or earlier in preservation I do not know) but the previous owner had sourced a pair of cast end plates which were unmachined and came with the wagon when I brought it. The end plates have a groove 1/2” deep and 1/4” Wide, into which the 5” OD steel tube which forms the casing of the heater sits. The tube sits inside by 1/4” then there is 1/4” of gland packing at the end to make the seal. The end castings then have a 3/4” draw bolt passing through the two ends to pull them tight. forming the spiral copper piping was an intersting job, which actually went better than I was expecting! It is 1/2” bore thick wall copper tube, I annealed it for about 18” at a time then wound it around a mandrel, I found I could only do about half a turn before it worked hardened and needed re-annealing but was pleasantly suprised with the outcome (shame nobody will ever see it!) Interestingly there is almost 3m of pipe in total in the feed water heater (it’s Only 16” long when fully assembled!) The feed water heater is held in place by two brackets which bolt through the chassis. This was the first job done completely in my new home workshop, so it was nice to actually use it! Again, I hope the photos show what I’ve been upto better than words!

Sorry for the lack of Foden updates, I’ve still been plodding away but kinda haven’t really got much to show for the work, also I’m terrible at remembering to take photos recording what I’ve been up to, but here’s a quick update: The crank was in worse condition that I feared, as “steam people” will know, the big ends are lubricated via a oil pot mounted on the big end strap, which commonly either have a wool “trimming” or a pin which acts as a jumper so when the crank goes round the jumper lifts slightly and an amount of oil is fed into the bearing. Usually this is at the top of the oil pot, but on early wagons it is a long pin which opens at the bottom to allow the oil through (hopefully my photos will show this better than my wording!) At some point the pins had been replaced and the new ones were too long and so have been hammering on the crank (this problem was corrected by the previous owner who fitted new, shorted pins) but they must have been in there a long time as they had scratched grooves into the crank pins which were nearly 1/8” wide and 1/4” deep! The crank was taken to “Field Engine Services” in Leytonstone (who I can’t recommend highly enough - the workshop is a real time warp, and they completely understand our era engines and are very sympathetic) they had to repair the crank webs by submerged arc welding followed by grinding the main and big end journals. The end of the crank where the gears run was also worn and tapered, so this was also ground. The key ways on 5 ton fodens (very different to later 6 ton versions) are dovetailed into the crank, these keyways were worn and the keys loose so everything rattled about so the keyways needed truing up, again this is outside my engineering ability so I took the crank to Inca Geometric in Chartham who did these for me - and again made a lovely job of it. New keys could then be ground to suit and fitted so everything is good and tight again and good bearing services. The roller bearing eccentrics were very very tired, and so needed to be totally rebuilt, again this is well out of my capabilities but I am very fortunate to know an excellent engineer who does lots of vintage car work (Paul Smith Precision Engineer, Gaza Barracks, Sevenoaks Weald) who could do them, so all four (in two pairs) have been remade. This is who also did the dovetail keys. Something which I found interesting was that the crank has never had any paint on it. It was previously a black colour, but that was simply years of grime! Upon degreasing the crank cleaned up well, so will he left as bright steel as original. I suppose what’s the point in painting it as it’s out of sight and why waste paint on it? - any thoughts please? So the actual crank is finished, I need to make a new gear carrier (which slides on the dovetail keys) as obviously the diameter has changed since grinding, for the same reason (and that the old ones were completely knackered) I next need to remake the main and big end bronze bearings, but that’s proving to be quite headache inducing - I’ll explain more about that in a future post...

Good morning all, if it’s of interest I‘ve came across this photo on eBay, item number 333814538193 Happy new year all. David

thanks for sharing, what a lovely piece of film.