2512silverfox wrote:
Bullied therefore had several underframes welded and then disguised by the addition of welded rivet heads so that the underframe appeared to be rivetted. After some time in service he then showed one of them to Gresley, who was pretty cross but acknowledged that they could be welded in future. Pity history does not relate which vehicles they were except that they were built at York.
Somewhere in the dim and distant I read a book about something "LNER" and there was a reference to the introduction of welded underframes. Bulleid had arranged a demonstration in one of the works where he got a man to take a sledge to a footstep. The footstep had been welded to the solebar and the man bent the step up and back through 180 degrees without fracture of the weld.
I suspect that the book was about either Gresley or Bulleid and the author was probably O S Nock.
gdb wrote:You say that the rivetted and welded styles are different in the shape of the diagonal cross bracing - is this a reference to the diagonals in the vertical plane which form part of the central cross-girders?
gdb wrote:You say that the rivetted and welded styles are different in the shape of the diagonal cross bracing - is this a reference to the diagonals in the vertical plane which form part of the central cross-girders?
Yes.
Still do not believe that you could be in trouble again, surely not for just helping those who do not have anywhere near your knowledge. I - and I suspect many others - am very grateful for the time which you must spend to provide the information as requested.
I can see what you mean about the difference in the diagonal angles of the central cross-girders. The JLTRT etches for the steel angle underframe produce the diagonals as per a rivetted underframe. Although the etches produce a rivetted underframe as supplied your photos suggest that it would be possible to modify the cross-girder etch to have the diagonals as per the welded underframe.
Each Gresley coach kits comes with castings for the queen posts and turnbuckles of the truss-rod underframe and with etches for the angle underframe. So having now learnt something about the methods of underframe construction, there is the inevitable question (and one which will help a couple of other members of this forum who are building JLTRT kits).
For the diagrams D113, D114, D115 and D175, which of the three styles of underframe could have been used with those diagrams? For example:- D114 probably truss rod or rivetted angle and maybe not welded angle. What about the other diagrams?
gdb wrote:Still do not believe that you could be in trouble again, surely not for just helping those who do not have anywhere near your knowledge
Only that my photos kept getting quoted and were adding to the confusion. I was losing track!
gdb wrote:
For the diagrams D113, D114, D115 and D175, which of the three styles of underframe could have been used with those diagrams? For example:- D114 probably truss rod or rivetted angle and maybe not welded angle. What about the other diagrams?
Unless you have a photo of a specific vehicle I would suggest you base the underframe on when the coach was built. The steel angle started to be introduced around 1930 for the 65'0" underframes. Harris quotes the first welded underframe as being for D186 built in 1934 with a gradual changeover from rivetted to welded during the 1930s. There are pictures in the Doncaster archives that show some D114s with turnbuckle underframes as late as 1932. I believe the general changeover occurred late 1932 for 61'6" stock.
I agree with you Mike with your assesment of the change of underframes, plus you will notice that my welded underframe drawing differs from yours in the bracing at the battery boxes....different manufacturers for the same carriage type for the same company..Aaaahhhhhhhhhhhhhh
Who said they were standard Gresley carriages....have him shot
I need to look at all my info in a small dark room with a good supply of gin, as I'm now confused of York.
gdb wrote:
Where is the bracket mounted on an angle-iron underframe? If anyone has an alternative angle-iron underframe drawing which shows a comparable section... or a photograph... then I shall be pleased to see same.
I think I have resolved the bracket location for steel angle underframes. You can just about see it in this enhanced section of an earlier photo and enlargement from the drawing. It is bolted to the face of one of the cross members, the pivot itself being located below the cross member. I would guess this makes the pivot point the same height as for turnbuckle underframes.
MikeTrice wrote:I think I have resolved the bracket location for steel angle underframes. You can just about see it in this enhanced section of an earlier photo and enlargement from the drawing. It is bolted to the face of one of the cross members, the pivot itself being located below the cross member. I would guess this makes the pivot point the same height as for turnbuckle underframes.
Image408d.jpg
bracket.jpg
Excellent detective work there, thank you Mike.
Harking back to the question of the central pull-rod of a brake coach on an angle underframe, your extract from the underframe drawing and your comments offer some light on the matter. My conclusions from the discussions to date, open for comment, are:-
Truss rod underframes have the girder for the Queen posts at a lower level than the solebar / longitudinal members and so the T-bracket / levers / pull-rods are necessarily lower than the solebar.... probably in line with the top of the fork on the cross-shaft. The pivot on the bracket is above the bottom edge of the cross-girder hence there is a need for holes in the girder for the central pull-rod. [Mike - is there a name for this girder?]
Welded angle underframes have a L-Bracket mounted on the cross-girder with the pivot below the girder, the pivot is possibly at the same vertical / horizontal position as on the truss rod underframe. The diagonals of a welded underframe do not meet at the centre of the cross-girder hence there is space for the central pull-rod to lie between the diagonals and under the girder without making any modification or allowance for the pull-rod.
Rivetted angle underframes, humm. The diagonals appear to be continuous between the tops and hence present the bottom edge of the cross-girder assembly is lower at this point. If this underframe has the same bracket as the welded underframe then some allowance in the design would need to be made to accomodate the central pull-rod (based upon a photo to this thread which shows a recess, in the framing, between the upper ends of the diagonals).
Oh for a drawing of a rivetted angle underframe... is it too much to hope for a late Krinble prezzi?
Truss rod underframes have the girder for the Queen posts at a lower level than the solebar / longitudinal members and so the T-bracket / levers / pull-rods are necessarily lower than the solebar.... probably in line with the top of the fork on the cross-shaft. The pivot on the bracket is above the bottom edge of the cross-girder hence there is a need for holes in the girder for the central pull-rod. [Mike - is there a name for this girder?]
Correct and I have seen the term Needle Beam. It is a 6" x 3.5" x 0.5 inch "L" section according to my records.
Welded angle underframes have a L-Bracket mounted on the cross-girder with the pivot below the girder, the pivot is possibly at the same vertical / horizontal position as on the truss rod underframe. The diagonals of a welded underframe do not meet at the centre of the cross-girder hence there is space for the central pull-rod to lie between the diagonals and under the girder without making any modification or allowance for the pull-rod.
Correct although I do not have photographic proof of this, it sounds reasonable.
Rivetted angle underframes, humm. The diagonals appear to be continuous between the tops and hence present the bottom edge of the cross-girder assembly is lower at this point. If this underframe has the same bracket as the welded underframe then some allowance in the design would need to be made to accomodate the central pull-rod (based upon a photo to this thread which shows a recess, in the framing, between the upper ends of the diagonals).
Again correct. The black and white photos are for a rivetted steel angle underframe and the drawings are for a welded underframe.
Summarising the timelines of the various types of underframe construction mentioned above:
1923 = bar trussing and Queen posts (with 4 trusses on the 60' but only 2 on the 51' underframe), all underframes to be built at York;
1927 = all-steel passenger brake vans to dia. 45 constructed by Cammell-Laird had trussing eliminated, as did all-steel open 3rds to dia. 28 constructed by Metropolitan C&W, these vehicles only;
1931 = non-convertible sleeping cars to dia. 148 constructed on new 65' underframe using angle trussing (rivetted); (1932 = first all welded wagon underframe constructed at Dukinfield in December);
1933(1) = Alpax carriage constructed on conventional bar trussed 51' underframe;
1933(2) = Tourist stock twin open thirds to dia. 171 constructed by Metropolitan-Cammell on short angle trussing underframes;
1933(3) = York carried out experiments with welded underframes;
1934(1) = open 3rd to dia. 186 constructed on all-welded angle trussing underframe in February;
1934(2) = start of a gradual changeover from rivetted to all-welded angle trussing underframes "until all underframes constructed in the Company's shops were dealt with in this manner".
Information extracted from and cross-checked against Harris' LNER Carriages, Newsome's Paper, HAV Bulleid's Bulleid of the Southern. The two articles on carriage building at York published in the LNER Magazine during 1928 and 1931 are too early to discuss these changes; the October 1931 issue has an article on the long sleeping cars but merely mentions that the underframe is built entirely of steel, while the August 1933 issue has an article on the experimental welded wagon underframe. I cannot immediately find any reference to rivetted/welded carriage underframes.
Brown's Nigel Gresley Locomotive Engineer has very little to say on the subject, but HAV Bulleid clearly places the initiative (for welding) with his father, with Gresley very much remaining to be convinced hence the elapsed time before all-welded underframes became the norm, as confirmed by 2512silverfox's note of his interview wirh OVSB.
It's clear that some confusion will arise from, not least, doubts as to whether certain batches of carriages were constructed using (a) bar-trussing (b) rivetted angle trussed, or (c) welded angle trussed underframes. Whilst the differences between the latter are less visibly important, knowing when the changeover from bar to angle trussing took place for any given diagram will probably prove impossible.
Railway Engineer was always good for technical details and drawings - anyone have 'easy access' to indexes or copies?
65447 wrote:
1934(1) = open 3rd to dia. 186 constructed on all-welded angle trussing underframe in February;
1934(2) = start of a gradual changeover from rivetted to all-welded angle trussing underframes "until all underframes constructed in the Company's shops were dealt with in this manner".
Just to add to this D186s 43612 (1934), 23956 (1936), 24105 (1936) and 56856 (1938) all have rivetted underframes so it certainly was not quick.
Addendum:
Going through the official photos I would suggest that vehicles turned out by York works from 1934 featured welded underframes (e.g. D27A 21308) however rivetted construction seemed to linger at other works until quite late in the 30s.
I find it interesting that of all the preserved Gresley panelled vehicles on steel angle underframes, only BCK D175 no 24068 at the SVR has a welded 60'0" underframe that I know of. Does anyone know of any others?
There was a modification to the welded underframe design around 1938 which I am still trying to rationalise. This might account for one of Dave's comments earlier about the two styles of welded underframe cross bracing.
[quote="MikeTrice]I find it interesting that of all the preserved Gresley panelled vehicles on steel angle underframes, only BCK D175 no 24068 at the SVR has a welded 60'0" underframe that I know of. Does anyone know of any others?[/quote]
LIke this one? An Open, non-brake, coach. Minimal number of rivets in solebar, diagonals welded to upright of central girders? Sorry, I cannot put a number to this coach on the SVR, photo by and with acknowledgement to Richard Carr.
MikeTrice wrote:Addendum:
Going through the official photos I would suggest that vehicles turned out by York works from 1934 featured welded underframes (e.g. D27A 21308) however rivetted construction seemed to linger at other works until quite late in the 30s.
Mike,
How does that rationalise with the 1923 decision that all underframes were to be built at York? (Although it's pretty obvious from the lack of trussing or early adoption of angle trussing/welded underframes that Contractor-built carriages were not included in this arrangement - perhaps OVSB was responsible for the specifications for these?)
Dave wrote:Those rivets you refer to are bolts used to attach vac cyls, battery box stays, brake hangers etc.
Just so Dave, minimal - in that there are none?
In passing, there was a recent post from Mike which I do not uderstand....
MikeTrice wrote:There was a modification to the welded underframe design around 1938 which I am still trying to rationalise. This might account for one of Dave's comments earlier about the two styles of welded underframe cross bracing.
I have searched through this thread and I am not sure that I can identify the post to which Mike refers in the above quote. If you are able, please point me towards the relevant comment as I must have missed this comment about different forms of the welded cross-bracing.