Kit 12 - Boiler Assembly

ModelWorks 4 inch Scale Burrell Agricultural Traction Engine

Saturday 26 Feb: Today I plan to start assembling the Burrell.  The method of assembly  given in the instructions requires the boiler to be moved during assembly.  I am concerned that It will become too heavy for me to safely manipulate so I positioned the boiler so that I will not need to move it until I have fitted the wheels.

I found I could gradually "rock" the boiler up to the required height.  First I raised the boiler barrel above horizontal with the boiler resting on the rear of the fire box.  This enabled me to add a block at the front of the fire box.  Next I lowered the barrel so that it was support on the front block enabling me to insert a block at the rear.  I repeated this until the boiler was sufficiently high to provide enough clearance to fit the wheels.  (27/2/05) Now that I have fitted the wheels  I can state that the minimum height required is 6 5/8 inches however I would recommend at least 7 inches to provide clearance to slide on the wheels and to allow for differences between individual models. As I was uncertain, my packing is 7 3/4 inches above ground level. 

The first task is to fit the cylinder.  Studs are fitted to the boiler barrel but only after the cylinder is in place.  To tighten the studs Modelworks supply a dome nut into which a ball bearing is inserted. The ball bearing prevents the stud jamming into the top of the dome nut.  The nut is screwed onto the stud and when the time comes it can be removed by turning sharply in reverse.  This worked well and there was no tendency for the nut to bind.  Unfortunately after only doing about 5 studs the dome nut broke while partway tnrough inserting a stud.  It looks like the ball bearing was pushed though the top of the nut.  Looking and the fracture I suspect that the dome nut was made in two pieces; after all the dome is normally only intended to be cosmetic

The technique is definitely the right way to fit studs so I adjourned to my workshop and made a replacement dome nut  with a substantial metal  top.  Another advantage of this technique is that the bottom of the nut can be used to gauge how far the stud has gone in and thus distinguish between a tight stud and reaching the correct depth.  

I found that some of the studs did not go in sweetly and if I had my time over again I would have checked out each tapped hole before covering the boiler with foliac and fitting the cylinder.  Great care is needed since it would be an expensive disaster to cross thread one of the studs.  I suspect that subsequent to taping some of the threads were damaged.  

Access to insert some of the studs was difficult, I probably should have removed both cylinder covers.  There appears to be an interference problem with two of the studs at the front of the cylinder. One is just below the blower take off port and the other is just below a mounting stud for the blast pipe manifold.  I had to remove this stud to fit the cylinder mounting stud and in the picture it is on propped in place since the top of the other stud fouls its line.  Like wise, as it stands, it will be impossible to fit the blower pipe. 

When I tried to fit the hornplate assembly the front spectacle plate fouled the boiler.  In the picture right the spectacle plate is resting on the boiler indicating that quite a bit of metal will have to be removed.   To enable assembly to continue I temporarily raised the spectacle plate by "one hole".

I was pleased to find that when I used the alignment jig to check the distance from the bearing to the cylinder it was spot on at 469mm. 

It is not going to be a quick job. Today I have managed to permanently fit the cylinder and trial fit the hornplates. 
 
Sunday:  I spent the day consolidating what I achieved yesterday.  When I tightened up the hornplate securing bolts there was no discernable distortion, if anything the crank alignment tool became freer.  As far as I could make out everything is in the right place except that the bottom of the spectacle plates are too low. 

I did manage to trial; assemble the wheels as shown right. The same picture is available here at  1600x1200.

Wednesday: Over the last few days I have been in contact with Steve and I now have an idea of the way forward.  Those with boilers will be hearing from ModelWorks and those without will benefit from updated instructions.

Steve confirms that the bottom of the front spectacle plate will have to be trimmed to prevent it fouling the boiler.   Mine needed 5/16" trimming from the bottom arch but there will be variation between boilers and Steve advises waiting until this can be accessed.  This is not the first time this spectacle plate has been reworked. 

I scribed a line using a pair of dividers and removed the bulk of the metal in the mill and cleaned up with a half round file.  Instead of a mill I could have used an angle grinder or even removed the entire amount with the file.  As can be seen above the spectacle plate now fits perfectly.  I would imagine returning to ModelWorks will be a option.

A problem exists with the rear spectacle plate that will prevent fitting the manifold.  Steve has a solution in mind and in the mean time advises against fitting the rear spectacle plate.  I shall be omitting both spectacle plates until I have finished the modifications and repainted them.

In the picture right it can be seen that the boiler in encroaching on the space need for the steam fitting.

Two of the front studs interfere with the fitting of the blower and blast pipe.  Since discovering this problem I had been dreading their removal, when it came to it they were easily removed using a pair of locked nuts.  

I shortened both studs by 150 thou and shaved 50 thou from the nuts.  When refitted there was sufficient clearance to refit the blast's pipe's stud including a nut.  To demonstrate the clearance above the blower port I screwed in a short length of 3/8 pipe.  With my stud modification the clearance beneath the pipe was 20 thou.  (Note: I have reduced nut thickness by 50 thou)

26/9/05 In addition to these two studs two more studs need to be shorten to allow the fitting of the cylinder drains. see here

I have included the picture right to show how well the shortening the front studs worked.

Thursday: Today I fitted the smokebox.  For this step the instructions suggest upending the boiler.  While this would make fitting easier I didn't want to move boiler.   Even with the boiler horizontal fitting the smokebox was relatively easy, all that was necessary was to drive the rivet bolts in with the dolly supplied in kit 1.  All holes aligned and I did not have to use a reamer.

I had planned to fit the steering gear tonight  but I hit a snag all of my own making -  I had forgot to paint it!!!!  I will have to put this on one side until my next painting session.

Friday:  Unable to fit the steering gear until I paint it, I pressed on to fit the tender.  I have never fitted the tender to the hornplates except very briefly before the axle tubes were fitted.  With hindsight this appears fool hardy but I now have no choice but to press on. 

When I offered up the tender it was slightly narrower than the hornplates.  This was not preventing fitting but it was causing the paint to be scraped off.  Using a hydraulic jack and blocks of wood I was able to slightly  widen the opening.  I was now able to being sliding the tender into position.  This was relatively easy at first but with about an inch to go I could make no further progress.  To avoid damaging the paint work I ruled out using a hammer.  I then had an inspiration -  I inserted the axle and placed a block of wood across the back of the tender and then with pair of sash clamps between these points I was able to pull the tender into position.  This worked amazingly well, the yoke of the tender around the axle tube guiding the tender into its correct position.  Fortunately I have got away with my reckless oversight but I should have checked the tender fit long before this point.  A small niggle, the tender should be held on with 15 bolts only 14 were supplied in the kit.
 

Saturday:  Today I tackled the gear guards supplied in kit 18. The instruction suggest using the "gentle persuader" and they are not kidding.  It took quite a while to get them fitting properly.  I am glad I left off painting them and I will now remove them and add them to the growing to be painted pile. 
 
Sunday:  Assembly of this kit is nearing completion.  If I did not want to put the car in the garage I would have liked to have left the engine on its blocks.  I hate clearing snow and ice from the car in the morning.

Way back I had planned to get a folding workshop crane from Machine Mart but Steve suggested all I need is a pair of bottle jacks.  At the time I could not see how they would help but now I am glad I took his advice.  With bottle jacks positioned under either hornplate (at the point where the tender joins) I was able to gently raise the engine and remove the blocks.  Things were made slightly harder as one of my jacks was a bit high.  I would recommend getting jacks whose minimum height is 160mm or less such as the Clarke CBJ2.

All that is left is to stand back and admire the Burrell.  Well done ModelWorks and especially Steve.

The above picture is available in 800x600 1024x768 or 1600x1200. An alternate view, taken with the camera lower down, is available in  800x600 or 1600x1200.

I was surprised how easy it was to move the Burrell.  This was made easier by not having the steering fitted.  Pushing on the top of the front wheels gives a mechanical advantage of two and allows the engine to be steered.

I currently have only "used" kits 1 -12 and I would recommend constructors who have yet to start to build the kits in numeric order as originally intended.    I did not want to fit the main gears and winding drum as they are on the painting pile. To prevent the back wheel creeping in  I have made spacers from plastic pipe.