You can set the sort order of messages? Just click on the link in the date column. Your preferences will be remembered, so you don't have to do it again when you return.
Just been steam testing Helen now that the boiler is finished. I used
the propane torch through the firehole rather than coal as it's more
controllable!
As suspected, the PEEK piston valves were still too tight at the
normal running temperature so I had to keep removing them and skimming
a fraction of the diameter until they were ok. A bit fiddly but
fortunately not a big job as the valves are easy to remove and
replace. I tried measuring the cylinder temperatures but my
thermometer only goes to 150° C and that disappeared off the scale!
The superheaters are stainless radiant type which extend to the back
of the firebox so the steam is well and truly hot!
I noticed that the lubricator doesn't seem to be pumping properly so
the cylinders are probably being starved of oil. I'll look at that
today. It didn't seem to affect the running though as I ran her for
about 30 minutes non-stop last night with no problems.
Looks as though I might be struggling to have her running for Stafford
on the 27th.Depends on how quickly I can knock the tanks and cab up.
Otherwise it's a big water tank on the driving trolley!
Have started work on my version of Helen Long and will post photos etc as work progresses. I've used Black Five wheel castings for the driving/coupled wheels ...
... John, how do you "locate" needle roller bearing on the axle, to prevent sideways movement of the axle? the only way to it reliably it seems is to use...
Hi Chris, The bearings are pressed into normal type flanged axle boxes, the bearing just replaces the plain reamed hole. Axial movement is controlled by the...
... against the flange of the axle box, as in the plain type. I considered doing the same, but felt that the advantages of needle roller bearing would be...
Hi Chris, I think any side friction will only be a problem when going around tight curves but we'll see. It certainly won't be any worse than with plain axle...
John Do you have the Helen Long drawings? I know somebody who would love to get his hands on them. David ... etc ... Longs ... has ... correct ... as ... ...
Hi David, No, unfortunately I don't have any original drawings, only a copy of the original series in ME. This is why I am trying to produce a set of full size...
Hello John, Showing my ignorance, could you please tell me what “PEEK” piston valves are? Is this a material similar to Teflon? Thanks! Keith Taylor...
Hi Keith, The material I've used is a bearing grade thermoplastic containing 10% Carbon Fibre, PTFE, and Graphite, which goes under various names such as...
Hi John, It sounds like a very intriguing material! I wonder how suitable it would be for piston rings, and rams for small steam pumps? I’ll have to check to...
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