Steam Department

The dog days of summer continue.  Many people have vacations or other better offers so turnout at the shop is lower than usual.  I had to leave in the early afternoon so hopefully others things were achieved later in the day. 

Anyway, I think we turned a corner this weekend.  We have just about completed the stripping and measuring and are now working on repair and rebuilding tasks.

Work focused on 1630:

·         Jeff, Collin and I measured the radius profile of the back head to provide Bob the last data for the form 4 calculation.  I need to finish a few more diagrams to identify exactly where measurements were made on each part of the boiler and Bob has a mass of calculations to complete and document but we now have all the physical measurements to complete the documentation;

·         the holes for riveting the patch into place have now all been prepared;

The rivet holes have now been drilled

·         Jeff and Collin marked all the points where we need Dennis to make good small marks in the tube sheets before fitting the tubes;

·         The big exercise now getting under way is the repair and safe ending of the super heater flues

o   Phil sand blasted the material that will be cut to provide the safe ends;

Phil prepares for sand blasting action

Preparing the material for the safe ends

o   all of the flues were inspected and those with an existing weld too close to the end were identified and cut to ensure that there will be an adequate length of clear tube at the end for expanding into the tube sheet;

o   each flue was marked up with the position into which it will be refitted (the spans vary a little so from here on all the measurements and amounts to be added will be specifically calculated to fit the tube to it chosen location);

o   a start was made on cutting the small diameter safe ends for some of the flues.

Collin and Ralph preparing safe ends

Bob and Ed worked on reassembling and firing up the rivet furnace.  It was test fired during the afternoon so hopefully we are now ready for riveting 428's cab.

Tom tests the rivet furnace

Glenn inspected and lubricated the boom hoist mechanism on the Bay City crane.  As the most frequent operator of that crane I have a vested interest in this activity.  The boom hoist has always been very tricky to engage and disengage smoothly so any improvement in this area will be a major benefit.

Don't forget the Steam Department benefit next Sunday.  You can still order tickets but will need to pick them up on the day.

Nigel

The weather had a significant effect on work this weekend.

We had hoped to pull the Shay truck out and complete the steam cleaning but sharp thunder storms in the late morning meant that the wheel drop covers could not be removed to allow the shunt.

90 degree temperatures and high humidity made all heavy work pretty slow.  However some significant progress was made on 1630.

·         Despite the heat, Phil spent most of the day in the boiler with Collin in the morning and Jason in the afternoon and completed the measuring of all the back head braces using the webcam and "fork" approach.  Vince and I, outside the boiler recording the pictures, certainly had the easier end of the deal.  However the results were well worth the effort.  Having checked all braces it is now clear that all are the same size (1 3/8 inch diameter) so significantly stronger than the drawing shows.  The end result is that we are now sure that the bracing of the back head is a good deal more substantial than previously thought based upon the Frisco drawings.

·         Kevin did a great job on the top of the tender.  He has worked during the week as well on this and now has the whole top of the tank needle chipped.  He is close to the point of final cleaning and being able to re-prime the metal ready for repainting.

·         the measuring of the exact distances between the tube sheets for each super heater flue was completed.  This gives me my homework for the week.  Now I can work out the exact lengths we need for safe ending each flue and we can then get down to cutting and fitting the ends to the flues.

·         We also continued the measurement of the back head.  As with everything in this area, nothing is as simple as it first seems!.  The critical measurement is the area of flat sheet facing into the cab.  (The curved area where the sheet is flanged forward to join the side sheets does not require bracing).  The initial calculation assumed the flange was of constant radius.  Now we know it actually increases in radius as you come down the sides.  What initially looked like school level geometry is looking more like college level maths !!.

In other areas

·         the last bull ring for 428 is just about complete, which will free up the lathe to produce the new piston rod for the McCabe;

·         the honing of the connecting rod has reached an acceptable level of "roundness" in the rod ends so we were at last able to free up the pillar drill and the area around it;

·         the new numbers for 938 were completed and fitted to the front lamp so she now looks a little tidier.

Nigel