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Further facinating progress in the build of Eddie Gibbons K3 and H4


A last machining operation on the axleboxes was to profile the bottoms             Set of six axleboxes on a copy of the working drawing

                   A driving box in place in the guide                                          
 A temporary axle was made to check the alignment of the axlebox pairs when
                                                                                                                 fitted in the guides. A bit of careful filing and scraping corrected the fit

                 Both sets of frames with the axleboxes in place                                 
A coupled axle in the lathe between centres for rough machining  

 A toolmakers clamp on the lathe bed provides a back stop whilst reducing the centre of the axle, The head end of the machine has a saddle stop.

                          A journal being finish machined                                                          
 A pair of axleboxes on an axle


                         Coupled axles in place on the frames                                    A crank web bored for the axle and crank pin and the keyways broached


The axle drawing with revisions over several years as the project developed on paper.   Roughed out driving axle ends ready for machining of the keyways

                                     Keyway machining                                                                                   
Axle stub with finished keyway

                                Axle stubs and crank web blanks            
                                                   Machining a pair of crank webs (1)

                    Machining a pair of crank webs (2)                                                                    
 Machining a pair of crank webs (3)

                      Machining a pair of crank webs (4)                                                                      
Machining a pair of crank webs (5)

          Finished crank webs ready to receive axles and crank pins                                      
 Crank web with axle end pressed in after facing off

                     Crank axle being Drilled for dowels                                                                    
Keyways to crank pins being machined

Crank pins with keyways ready for finishing and final assembly by pressing into webs                 
 Crank pin after pressing in to web

                             Assembled crank axle                                                                        
Crank axle set up on rotary table for drilling dowels

     Assembled and dowelled crank axles ready for finish machining                                
A crank axle set up between centres for final machining.
                                                                                                                          Note the wheel seats are left oversize until the wheels are bored.
                                                                                                                         As these are a taper fit, once the machine is set to cut the tapers the wheel seats
                                                                                                                                and the wheel bores are finally machined to the same taper setting.

             A driving wheel casting set up for facing the back                                                                    
 Facing in progress

A wheel set up for boring. The centre is located by measurement from the inside of the wheel rim.

As this may not be truly circular some judgement is required on determination of the best location.

                            Starting the bore                                                     Dri
lling the bore                                                          Boring in progress                                                                   
 Once all the wheels are carefully bored to the same diameter a mandrel is made to fit in in the lathe spindle taper and used to set up the wheels for all further machining operations in the lathe and on the rotary table on the milling machine. A wheel is seen set up for facing.


                                     Facing the tyre                                                                                                 
 Facing and profiling the centre

                       Machining the inside edge of the tyre.
Note at this stage there was no intent to fit steel tyres. That came later.                                           
Machining the groove at the balance weight

                 Chamfering the edge of the balance weight                                                  
Rough machining of the tyre profile. Final profiling should be done after
                                                                                                                             the wheels are pressed on to the axles to correct any run out that may develop

     Back in the milling machine for rounding the back of the spokes. 
The wheels were reversed and the front of the spokes were also machined with a radius cutter. The spokes as cast were not perfectly regular in spacing and thickness and had some casting defects. Whilst time consuming the end result is a great improvement on the original cast.

The final operation  was to finish the spokes by hand with a round file.                                              
A typical casting fault in a spoke


An epoxy metal filler was used to finish the wheels where machining had not completely removed the defects.

After curing the filler is easily smoothed by hand with a file

 The wheels were then returned to the lathe, trued using a dial test indicator on the tyre and bored to a taper of 2 thousandths of an inch in the wheel thickness.

Once the wheels were bored the axles were returned to the machine and the wheel seats were machine to the same taper such that
the axle would enter the wheel bore by a third of the length of the seat.

When the wheel was pressed home this gave an interference fit of 1.5 thousands of an inch, a little over the recommended thou per inch.

 An offset mandrel was made and fitted to the face plate for boring and reaming the crank pin holes.

              The holes were started with a centre before drilling
                                                   And finished with a reamer.

A jig was made up to hold the broaching guides for the crank webs and this was modified
and reused for the wheels to ensure the axle keyway was exactly in line with the crank pin centre.

             A setting block was used to align the broach guides                                              
The wheel press was used to drive the broach for the keyway

The coupled wheel crank pins ready to be for pressing in to the wheels.                        
The driving crank pins were made as a pair and one is seen having the
                                                                                                                                 keyways cut using a between centres set up in the milling machine.

The rotary table was used to set the angle for machining the square for the
return crank, accuracy being essential for correct operation of the valve gear.                      
 The crank pins machined and ready to be separated

The same between centres set up in the milling machine was used to cut the keyways in the axles.
These needed to be accurately machined at 120 degrees so the cranks would be "quartered" as the wheels were pressed on.

                         Cutting an axle keyway                                                                                       
The other end after rotating the axle 120 degrees

The wheels are fitted to the axles with the keys on place and put in the wheel press.             
They should press on equally confirming the press fits are the same.

The crank axles need setting up carefully in order to get the correct relationship between the centre and outside cranks.

The wheel sets all complete save final profiling of the tyres and fitted in the frames.
Making the wheel sets took until November 2010, about 9 months from starting.

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