Kit 10 - Axle Tubes

ModelWorks 4 inch Scale Burrell Agricultural Traction Engine
I collected kit 10 from City link 6th August 2004 

Friday: What a hot day, too hot to tackle the Burrell.  When I collected the kit from city link the box was split open and I was handed one of the axles bushes.  Luckily on checking the packing I have all the bits.  The Axle had worked itself lose an split open both ends of the box.

Since I am in the middle of painting the hornplates I will have to delay some stages of this kit. 

Saturday:  Made a start on the rear axle. The first task was to get the bushes freely running on the shaft.  After de-burring both the shaft and bushes I could thread the bushes onto the shaft. At the location where the bush would eventually sit they would not turn freely so I looked for the high spots using engineers blue. I could find none inside the bushes but to my surprise I found high spots on the shaft.  Rather than use emery cloth on the shaft I scraped the high spots (using a sharpened old hacksaw blade).  I did not want to get abrasive particles stuck in the bushes as this could cause excessive wear later.

There were some fairly course machining marks on one end of the axle tube.  I tackled these with emery cloth and was eventually able to get both ends the same and looking good.

I trial assembled the axle temporally securing the bushes with bolts in the oiller holes.  I made the mistake of not scrupulously cleaning up before assembly.  Things were fine until I tried to remove the shaft when one of the bushes jammed.  I eventually managed to get it off with the aid of WD40.  After cleaning, I reassembled the axle, and all went well.

The last task of the day was to polish and assemble the oillers.  They are supplied as three components (Cup, inside & cap). 




 
Friday: I have encountered a small problem with the second shaft.  Before Loctiting the bearing bushes in place everything was fine.  After the Loctite had set I found that the axle would no longer fit.  I suspect that there was enough slop between the bush and the axle tube to allow them to slightly twist.  

Since the centre section of the axle has a reduced diameter I was able to use the axle as a gauge.  The picture right shows the slight misalignment, the far side of the axle is resting of the shoulder where the shaft diameters change. 

My next task is to scrap the bearing in order to correct the problem however I am currently fully occupied painting the inside of the tender.  

Post script: I should have temporarily fitted the axle whilst the Loctite was drying to ensure alignment.  

Saturday 21:  I have not spent much time on the Burrell this week.  What time I could grab midweek was spent sorting out the 2nd shaft axle alignment.  If I had known how much effort it would take I would have been a lot more careful gluing the bushes.

Today I completed assembly.  I had to remove about 10 thou from the end of the dif lock platform to get a good fit.

Now that I have finished the axle tube I am puzzled by the location of the bush, which as instructed, I positioned by reference to the oil hole . The differential will eventually run in the housing shown opposite.  It looks like it will rub against steel as the bush is recessed by about an 1/8 inch.   Perhaps this does not matter but I would have though the top of the bush would have been flush with the housing.

Tuesday: Set about cleaning up the bearing housings.  I found there was quite a bit of loose stuff  to shift.  This I achieved with a wire brush in the power drill though I did use a small chisel to dislodge some casting sand sponge. 

Wednesday:  Painted the bearing housings tonight.  Now that the paint is on I can see a few places where the castings look porous.

 Main crank bearing housing

Friday: Despite getting Kit 11 today I managed to find time to paint the axle tubes.  The picture below shows the bearing housings and axle tube laid out to dry.