Monday 16 November 2020

Making a Name For Yourselves

 

Back in February we were all excited by the dispatch of our first batch of patterns to the foundry. These included both the rocker covers and also the manufacturer's plates to attach to the engine & radiator.



Reference has been made before to the curious misspelling of McLaren on the radiator plate, which is of course irritatingly close to the driver's eye line. As a project being run by pedantic people the jury is still out as to whether this is annoying (as it is wrong) or if it is satisfying (as it is wrong but right). Perhaps it is just there as a conversation piece?



The McLaren–Benz plate is from the right hand side of the engine block and can be just glimpsed in this view of the donkey engine:


Not convinced? This is a view of the 4MDB in the Armley Mills winch from a similar angle:


If you would like your own conversation piece, we have a small stock of both plates available at £150.00. All profit to the project, contact us via the Facebook page. They have been cast in iron, but if you want to fasten it to a partition wall we might be able to do you one in aluminium. 

Not really after a big chunk of iron work for the chimney breast? We still have stocks of our other ‘merch’, books, T shirts & badges available from https://www.frheritage.org.uk/sales/



Friday 13 November 2020

Starting again

For obvious reasons 2020 has been a slow news year. In a rather different world last December, buoyed up by the additional funding provided by the Ffestiniog Railway Society, we dispatched the magneto from the 4HP Blackburne donkey engine for overhaul, hoping that this would be the catalyst for a side project overhauling the starter motor. The Blackburne engine sits on a cast iron frame in the cab which Rick machined up (blog entry 14 December 2019). We were hoping that our petrol engine man, Martin Greenland might be spurred on by the magneto overhaul and find time to look at the rest of the engine. Fortunately in late February the relevant box of bits left Boston Lodge and made it to Martin's workshop just before lockdown started.

Job number one was that the drive side main bearing was very loose in the crankcase. To effect a repair Martin machined up a thin steel collar to be inserted into the crankcase, which allows the roller bearing once again to be an interference fit in the casing:


What do you do if you need to insert a steel collar in a crankcase with an interference fit at home during lockdown?  Place your collar in the freezer to shrink it; place your crankcase in the oven to expand it; stick both on kitchen table and work bloody fast!


Bingo!


The bearing is secured by three 0BA countersunk screws. Even in lockdown you can buy these, but the heads on modern ones are 3/8” in diameter and it turns out that back in the twenties the head diameter was ½”, so another opportunity to while away the hours. The view below shows the fitted bearing, complete with Martins bespoke made set screws:


This is the inlet tract all cleaned up and ready for reassembly:


The cylinder head with the carburettor fitted:


The engine sits in a fabricated cradle, very similar to the one which supports the vacuum pump. There is one important difference; a bracket is needed to carry the magneto:


This is the donkey engine sub-assembly nearing completion, showing the new sprockets and chain drive to the refurbished magneto with the carburettor above. The chain guard cover (yet to be fitted) proudly carries the Blackburne makers name. It’s a pity, but this is the back side of the engine (inside the cab sheet), so all you will get in the cab is the flywheel and chain drive to the main engine:


So, the starter motor wasn’t quite the side show that had been anticipated, it is centre stage for 2020. Having this technically complex piece of work nearing completion is a great achievement.