Thank's Malcolm...actually, Adam just sent me an image of the crosshead, we had a wee discussion on it... I have seen the video before but didn't note the crosshead at the time, I did take a still from the video of the round dome which was what I was looking for at the time... That is identical to 4472 in 1936, by 1938 she had the pipe added, I'm not sure why this was changed, it's seen on a number of Pacifics and was the same for the V2's.
Here's 4472 at KX in 1936
And here she is again 1938, I can't recall where, she's heading north out of London KX.
after the chat with Adam, I looked again for smaller copper pipe, I have found some with 1 mm OD which is about half the size that I have used. I'll order some and see how well oil passes through it...
Pete loves it when he posts these details as I usually have some 'advice' we chat at length over the finer points usually!
As I said though Pete, still looking awesome!
Adam
Trying to Finish 5" 9f Producing Scale fittings using 3D wax printing and lost wax casting - www.crofittings.co.uk/ Renovating house stopping all of the above!
Hi Pete, You could always get some copper wire the OD you want & drill it out......
Ok I’ll go back to drooling over your build.
Cheers Kerrin
Haha...now there's an idea... or better still, I could try the 1mm OD tube that I found on google today... I've ordered 3 lengths of 0.3 mm bore tube and 1 mtr of 1mm tube, no bore given for that one. Once it's here I'll do the oil tests again and if it flows I'll make up two more pipes.
I have never tried this, but you could get a draw plate of the type jewellers use for drawing down wire to smaller diameters. I reckon you could probably draw copper pipe down to smaller sizes and the hole might not close up completely...
that's a good idea, Chris.. I may try that if the tube that I've ordered doesn't work. a quick search shows that amazon do a few types, not cheap but one of them goes down to 0.26mm hole and has 52 different sizes which might come in handy later... I have a sense that the pipe I've ordered will work, just depends on how easy it is to shape, some are copper and some are brass. Some more experimentation ahead..
Hi Pete, Is it the OD of the pipe that’s the issue or the ID & hence oil flow that you are getting sorted? To slow the oil down did you consider putting a wick in the pipe? Or maybe soft solder the end & drill thru to give a flow orifice?
Hi Pete, Is it the OD of the pipe that’s the issue or the ID & hence oil flow that you are getting sorted? To slow the oil down did you consider putting a wick in the pipe? Or maybe soft solder the end & drill thru to give a flow orifice?
Cheers Kerrin
Hi Kerrin
It's purely cosmetic...the pipe is about twice the OD that it should be and also I've been a little lazy in fixing the pipe directly into the end of the gudgeon pin rather than via an elbow. Oil flow is fine. I have ordered some pipe that's 1 mm OD, half that currently fitted. I'll see how easy it is to shape and make more scale like ends...
A case of 'watch this space'...mean time, I'll get on with the outside connecting rods...
Well, I got my micro tube today, I opened the packet and thought, they've sent me wire by mistake? Nope, when I saw tube at 0.3 and 0.4 mm I had assumed it referred to the bore size. Alas no, it's the OD, how the hell do they make meter lengths of tube with a 0.22 mm bore? And the 0.3 mm size in 12-inch lengths has a bore of 0.12 mm? I can't even see the tube properly without trying to see if it has a bore, however, I did test it in my cup of coffee which was conveniently sitting in from of me. It was like the old wolf, huffing and puffing to blow air down this tiny tube, I was rewarded with the tiniest of bubbles forming in my coffee, so yep, they are definitely tubes'...
so these tubes (btw they are brass but I can deal with that) will be consigned to the 'O' gauge cupboard and I've just reordered larger sizes. This time I read carefully what was on offer and now have coming
0.6 mm OD x 0.4 mm ID 0.8 mm OD x 0.6 mm ID 0.9 mm OD x 0.7 mm ID
The largest is about half the OD size that I currently have on the crossheads and yet has a larger bore, I think that I'll be able to make true scale pipes as long as i can carefully form them.. should be doable.
A picture with the tubes laid against an ME mag for size comparison, just to show how difficult they are to see. There's about 6 or so lengths in the 0.4 mm OD tube.
Well no blog entry this week due to the mill throwing a wobbly and thus stopping me in my tracks with the connecting rods, I had hoped to have them finished today. Oh well, I need to strip the mill head down and find what's rattling like stones in a tin can....lol Not to be beaten, I took advantage of this downtime and revisited the pipework on the crossheads. I have added the details in the drop link blog entry. The solitary picture is shown below.
I have again updated the 'drop link' blog entry for what hopefully is the final word on the crosshead oil feeds. There are a couple more pictures and the short video shown below of the oil test, happy to report the test was very successful. As stated before, the lower pipe connection is a push in fit, relying on the spring in the pipe design to keep it in place. With the oil test being under pressure I think it's safe to say that the pipe will not come out in service.
Nice GG, did you flange the pipe or fit nipples, either way it looks fiddly!
Tim
Morning Tim
No, not nipples, the unions are dummies, the top is permanently soft soldered to the reservoir connector, the bottom is a push in fit with a brass nut and short section of brass hex tube soft soldered in place where it leaves a short section of pipe to be pushed into the gudgeon pin connector. The spring in the pipe keeps it in place. We'll see when running if that is enough on it's own to stop the pipe from coming out. The fact that it didn't under pressure of the oil being pumped through looks promissing
As some will know I spend a lot of time researching 4472 and Gresley Pacifics to help me with my project, I doubt that a week passes without me trawling online for new info. today I received the lastest fruit of my endeavour, this time a Davies & Metcalfe booklet on both the vacuum and steam ejector's as fitted to Gresley's Pacifics. There is a lot of information in this booklet, diagrams of the various parts involved for both types, their operation and parts list. Also some info on pipe connections and details for both left and right-hand loco's. There are 3 great backhead photo's of Gresley's W1, A4 and of course his A1. So at least I now know the exact brake valve as fitted to 4472. I'll share a few pictures to give a taste of it's contents, the booklet itself consists of 36 pages, also thrown in are a couple of advertising pamphlets.
I've left the images in their raw size so that people can see them better..
Front cover
A1
Vacuum Brake injector
GA drawing, there are others covering the various parts and their nozzles, no dimensions given though.
Parts list
I guess I'll be doing a little more reading over the coming days..
well, that took some time to print...the link is to the 'J' class, I think that 4472 had the 'H' class for my era... they are pretty much the same thing although the later 'J' was a much more simplified injector and the most reliable too. The 'H' had an auto water feed controlled by steam, the more reliable 'J' has a manually operated water valve of the disc pattern combined in the water regulator. The 'J' also has the extra benefit of an automatic choke to improve the feeding of water at very low boiler pressures. 'J' works just as our miniature injectors do... water and steam vales, adjust both to suit pressure.
Yes, I've already begun reading, I have also downloaded the booklet for the H class along with some other interesting papers, including one on superheaters. I'll use the 'H' class profile for my own injector shape when I get there.
These downloads give great drawings for us model makers.
Glad they are of use chaps...I've been hunting for this info for years...still looking for the Gresham and Craven details. I think 4472 had 'H' too Don, I'm sure that I noted it down somewhere?
. I have seen the video before but didn't note the crosshead at the time, I did take a still from the video of the round dome which was what I was looking for at the time... That is identical to 4472 in 1936, by 1938 she had the pipe added, I'm not sure why this was changed, it's seen on a number of Pacifics and was the same for the V2's.
. I have seen the video before but didn't note the crosshead at the time, I did take a still from the video of the round dome which was what I was looking for at the time... That is identical to 4472 in 1936, by 1938 she had the pipe added, I'm not sure why this was changed, it's seen on a number of Pacifics and was the same for the V2's.
I can't even see the tube properly without trying to see if it has a bore, however, I did test it in my cup of coffee which was conveniently sitting in from of me. It was like the old wolf, huffing and puffing to blow air down this tiny tube, I was rewarded with the tiniest of bubbles forming in my coffee, so yep, they are definitely tubes'...
