What About The Bee

A further confusion is evident in the patent drawing. Look at the side elevation. The Traveling Engine is hauling a chaldron. There is a strange little pony cart between the TE and the chaldron. There is a chain! It runs from the TE to the pony cart. In the patent, Dodd and Stephenson provide the answer to what this is. They explain that the TE is expected to haul ~60 tons, but if more is desired, the pony cart is actually the tender and it can be made to increase the tractive effort. Applying the friction of the bearing wheels in this way, the engines propel 60 tons or upwards upon an iron railway. If a greater burden is to be moved, the friction of other two wheels is added, and they are made to carry the water that supplies the engine. A groove is made in each, and a groove in the last two bearing wheels of the carriage, into which an endless chain falls. By the propelling force of the engine this is moved along, together with the bearing wheels of the water carriage attached to it. The only other drawings of this pony cart are clearly derivative of the patent drawing. Caution is always advised with non-period drawings, but I find this one to illustrate the powered tender adequate. Bee

I accept that I am likely wrong about the Whyte notation for these early Stephenson Traveling Engines. The problem is that they do not neatly fit into that notation. The two pistons really aren't independent, nor are they completely dependent. This makes a muddle of fitting it into the notation. Example 1: the forward axle slips. The chain, being connected to the rear axle which is not slipping, halts the forward wheel slip and all the power of both pistons is applied to the rear axle. Example 2: The Traveling Engine is stopped. The rear axle is at top dead center. Thus, the rear piston cannot apply power to the rear axle. The forward axle, being ~90° out of phase, is at full power stroke. Apply steam. Does the chain merely keep timing, or is it applying torque to the rear axle? Example 3: The chain breaks during operation. Can the Traveling Engine make it back to the engine house? I say yes. Bee

I do understand the attraction of that crane https://www.hattons.co.uk/directory/vehicledetails/3142990/15_ton_cowans_and_sheldon_rail_crane 4 years, 8 months!?!? That's patience! 🙂 Maybe make your own? Bee

JJ, I did get the Tiger Train Pack.

My shortest? This year on range release, I pre-ordered the Tiger Train Pack R30233. That was the second Tuesday, 9 January. It came into stock 15 February. I received it very shortly thereafter. 15 Feb - 9 Jan = 5 weeks, 2 days My Longest? Any "withdrawn" item. It will never arrive, the meter keeps ticking.... Infinity? Bee

So there still is no certainty of an update, no matter how much 'preparation', since there are setbacks. Regrets, I've had a few... 🎵 No. No I do not. Requesting clarification. ÷÷÷÷ The word is "specific" Having suffered all too often from vapid statements, made by corporate drones, similar statements by 'Railmaster Support' are mind numbing. It's a feel good message that attempts to make you feel good, but primarily to just make you go away. It offers no actionable statements, nothing to hang your hat on. Perhaps someone can tell me, specifically what is included and when it will happen. If I were you @TimNiceButDimI would send a follow up. 1) What is the date certain? 2) what situation? I cannot read their mind. Prepare yourself for more mumbling disingenuous self serving platitudes. Bee

Hi @threelink The chain was replaced with coupling rods, when the second "Traveling Engine" made its way from Robert Stephenson & Co engine works. Likely by very late 1825, or by 1826. The S&DR complained that the second engine did not perform as well, in writing. This is what leads me to believe the chain was present on Opening Day. Active hauled an impressive consist, without complaint. Hundreds of people and tens of loaded chaldrons, not to mention the Experiment passenger carriage. That tremendous consist. It beggars belief to suggest that was done with an experimental engine. It had to be a Traveling Engine with understood mechanics. The Hetton Colliery engines, the predecessors, all had chains. I consider the Killingworth engine to be an 0-4-0, with the chains taking the place of the coupling rods. The chains were to take care of quartering. Bee

It cannot be that way @LTSR_NSE. Captive bolts cannot move relative to each other on the circumference of the blue link, the point of the illustration with numbers. How can the pivot point move, if the bolt is captive. It cannot. QED, the bolts are not captive. Other simple explanations are The illustrator was depicting what he saw, and that included wear. The illustrator wasn't concerned about mechanical accuracy when it comes to a minor point. The chains are fascinating to me (us?) but may not have held the same interest for the illustrator. The sketch is reasonably accurate but imperfect. Bee's pink circles aren't inserted to the nearest angstrom and this leads to angular errors. Any combination of the above. When @threelinkasked about friction and wear, the exact detail of construction became a critical input. If the chain was constructed with captive bolts, the wear would be substantially different from free floating bolts. That needed to be resolved first. I am more than happy to try other explanations. That alternate must fit all the facts we know or can derive. Sketch some blue and yellow links. Ignore my interpretation, but do examine the Wood's illustration, the patent drawing and the verbal description. Explain how the bolts move on the circumference from chain straight to chain on cogged wheel. I think you will find the simple explanation on offer to represent a logical choice Bee

The Chain Dilemma How, exactly, is the chain constructed? Choice 1: The bolt is free to float inside the blue link, as I have sketched. The bolts are 180° apart when the links are straight because of the tension on the chain. Choice 2: The bolts are captive in bores located on the inside wall of the blue link. The bolts are 180° apart when the links are straight because of the two bores. In fact, the bolts are always 180° apart. So what happens when the chain goes round the wheel with cogs? I superimposed light pink circles with a center dot for each blue link to help see the solution. For choice 1, the bolts aren't captive. If we draw an orange line from blue link center to blue link center, then the yellow links should be on those orange lines. For choice 2, the bolts are captive. Therefore, the pivot point is at each bolt. The blue and yellow link lines, corresponding to blue and yellow links, are drawn to the pivot points. Choice 2 appears to be wrong. Examine blue link 5, on the straight. The pivot points are 180° apart and the blue line passes through the center of the link. Yet examine link 3. The red line attaches to one pivot point and proceeds directly through the center of the pink circle. If the bolts were captive, the yellow link would intersect the end of the red line, nearest link 4. It does NOT. Thus, the bolts are no longer 180° apart for link 3. Similarly for link 2. It appears, therefore, that choice 1 is correct. But! The yellow links are not exactly on the orange lines. Go back to see. With the chain geometry resolved, what about friction, and specifically, wear? Assume the chain and wheel with cogs are perfectly sized. The center distance from blue link two to blue link three fits exactly in the space in the cogged wheel for those links. Precisely as drawn by Wood's illustrator. The blue links nestle into the cogged wheel and the yellow link, being a precise fit, is drawn to the orange line. Again precisely as drawn by Wood's illustrator. The bolt, therefore, slides along the inside surface of the blue link, under the tension force. I do not think the bolt rolls along the inside surface but I can be persuaded otherwise. There will definitely be retarding friction and resultant wear, due to the sliding. Sliding members are notoriously hard to lubricate. The bolt will act as a wiper, pushing any grease or oil to either end of travel. Thus, within a short time, the bolt will slide along the blue link, unlubricated. The inside of the blue link will wear, as will the side of the bolt held against it. As those surfaces wear, the chain stretches. The center distance between blue links lengthens. The yellow link will not be perfectly on the orange line, as it can and will droop away. Similarly, the blue link will droop. The wear on the inside of the chain will be reduced as members are not held under load. This exactly matches your instinct, ThreeLink. The outside of the chain will then wear, as will the cogged wheel, as the arc length in the cogged wheel and the chain center distance no longer match. Maintenance would be constant. Replacing links is straightforward. Wood mentions re-tensioning the chain which does not appear overwhelming. Fitting a new cogged wheel, because it too wears, will be the most labor intensive. Unless that cogged wheel is two halves that clamp around the axle, there aren't many other easy choices. Replace the entire axle, wheels and all? Slide the cogged wheel off one side? Bee

Hi ThreeLink Thank you for a thought provoking statement. There is a difficulty in the chain geometry that I am attempting to resolve. When the chain is straight, there is no difficulty. My CAD matches Wood's verbal description and drawing, perfectly. Yet when the chain goes round the wheel with cogs, there is an unresolved issue in matching the drawing. I will need a few days to reason my way through. Please do bear with me. I will make every effort to resolve the geometry issue and with it, answer the friction question. Bee

I thought to closely examine the chain itself. Wood, Practical Treatise, 1825 provides us with an unusual description. "This endless chain, which is now solely used upon these kind of engines, consisted at first of one broad and two narrow links, alternatively, fastened together at the ends with bolts; the two narrow links were always outside of the broad link; consequently, the distance they were separated laterally would be equal to the breadth of the broad link, which was generally two inches, and the length three inches" Quite the sentence and difficult to understand. I puzzled over this sentence. Nicholas Wood was in a prime position to understand the Killingworth engine. He was appointed an assistant colliery viewer at Killingworth, in 1811. His superior? Ralph Dodd. Dodd, of course, the other patentee with Stephenson in 1814. Indeed, Wood became Killingworth Colliery Viewer in 1815. In 1818, Wood and Stephenson performed experiments with a dynamometer they designed, at Killingworth. ( https://community.hornbyhobbies.com/forums/topic/33593-railway-oddities/?do=findComment&comment=368416 ). Nicholas Wood was there and had genuine first hand knowledge. Wood was in a unique position to evaluate and describe the chain. I do think this is the solution. The blue links are 2" wide, 3" long. Two yellow narrow links are on the outside of the blue link, as specified. The red bolts go thru the blue and yellow links. I've sketched in gray nuts, but these are not mentioned. Take a moment to read the description from Wood as you study my solution to the chain. The chain fits the description. I was studying the (unfortunately low resolution) patent drawing for UK Patent 3887 Dodd and Stephenson. I turned the drawing sideways, and wow, there it was. UK Patent 3887 Dodd & Stephenson There is a long thin object drawn there. Examining it in detail, I can see the side plates (yellow) and the blue links. The ratios of width and length are not as described in Wood but there nonetheless, along with the red bolts. That is typical of many patent drawings. Deliberate proportional errors to throw off your competition. So the real question now is the shape of the blue links. Are they made of rod, like standard chain or are they cylinders, as I have drawn. The rear elevation view of the "Killingworth Locomotive" (per Wood) shows the wheel with cogs and the chain. The asymmetric object to the right on the axle is the eccentric for driving the slide valve. Wood's Slip Eccentric, if you please. Returning to the wheel with cogs, we can observe the yellow side plates. The blue links between the side plates show straight lines side to side, not curved. So from this I conclude that the blue links are indeed cylinders It is quite tricky in this end view to make out what is the wheel with cogs, and what are the blue links. The yellow narrow links are clearly present however. As the blue links are two inches wide, then the wheel with cogs must be just under two inches wide. That is very robust sprocket indeed. This chain can not twist and fall off the sprocket. Once again, the resemblance to a bicycle chain is startling. The chain is such a unique railway feature, that it forms part of the patent claims and drawing. Bee

No complaints here. Looks great! Chrome is also very tricky to photograph so that it stands out. I can see the handles and handrails, without a doubt, and chrome they are. Effort not wasted. Bee

I grabbed it from Deem's post Bee

Deem, you just need to rotate the wheel vs the axle! Use a straight edge to verify that they are in line.. Mind the back to back. Bee

@Deem Is the quartering out? This may be an artifact of your photo, but it looks to be 5 to 10° out of phase Bee