Thanks Frazer
- Yes, Tipex also works; I've used that with silver soldering. But I tend to get that all over the show
. For silver solder I now use a soft ("B" or "2B") pencil and just colour in a ring around the bits; works a treat. I must actually try it with soft solder as well...
Arnold...I know you know I'm just having a poke at you.
I know
- Here's one right back Carl; you asked for it - in many more ways than one
I'm curious. Just what symptoms would characterize the dreaded Marv-itis. Perhaps a sudden outburst of optimism* or good will? (Believe me, if you think I'm bad now, wait until you see me cheery.)
Hmmm... Tel got close; but judging from his current non-Ausie style head-wear he might have too many Phi's buzzing around... To the sound of coconuts clapping, I'd say it's the ability to differentiate between European and African swallows, but then again, it might be a peculiar form of cheer around Christmas time
Bob and Jerry, thanks for those
. The Mery actually looks like it's a steam engine that's been converted to run as a gas engine (I'm assuming gasoline/petrol rather than natural gas) - but from the period, that fits the looks. The double-acting Diesels are just mind-boggling; the 14 cylinder must have enough torque to winch the Moon in! Come to think of it, the only way to make any type of double-acting engine work, one would need a cross-head...
Thanks Bill - we seem to have the same problems
- though I did manage to get some material this week.
Friday I managed to nip off to one of the local metal suppliers. It wasn't quite the right day to pitch there; they were doing their financial year-end, and that's a high-stress scenario. It's a "Local German"-run company, and anybody having anything to do with them initially might be a bit taken aback - even on a good day. To quote James Herriot : "They're not ower cheerful Guv". Wannabe model engineers tend to be treated as nuisances, but I've been carefully cultivating a relationship with this company; Give a cheerful greeting, try and be to the point, buy something, and don't haggle too much. And bring along finished engines and show them what I've been doing with the bits of metal I buy from them. They do tend to give me a lukewarm welcome nowadays ("Hello Mr. Bosch - what do you want?" from their point of view is cheerful and open-arms welcoming - I just wish they'd call me Arnold though), but on Friday the greeting was just "Look for what you need - you know where it is"...
I was looking for a bit of steel rod to make the cylinder heads from, and also looking around for something to make the flywheel from. A 55mm bar-end section 200mm EN8 long caught my eye for the cylinder heads - that would leave me with a good bit of stock left for other projects as well. There were no suitable large bits of steel for the flywheel, but then a section of cast iron hollow bar caught my eye. 180mm OD x 150mm ID and 100mm long. So with the two bits of metal in hand, back to their office. The cashier totaled things up - N$ 476.25, and OOPS... it was quite a bit more money than I had on me. They don't have card facilities... So she asked me how much I had, and I emptied my wallet right there on the counter. N$ 370 in notes, and just over N$ 10 in coins. I think emptying my purse on the counter really amused her, because she actually cracked a smile. She fiddled with the computer and discounts and printed me an invoice, and I came home with these:
I had quite a bit of time in the shop this afternoon, but there's not much to show for it.
I set up the steam/exhaust covers op on the lathe and skimmed one side of each down to get it flat and rid of mill scale. There was not much to chuck up on - but it was enough to get the job done. I also drilled a 2.5mm hole through the center (marked earlier on the mill while drilling the holes) of each workpiece at this point:
To finish the covers to thickness, I used a bit of thick cardboard between the 4-jaw chuck's jaws and the workpieces and the tailstock center to push them tight against the chuck jaws. For the exhaust cover I just turned it down to leave a 7mm boss, as I don't intend to add much plumbing on the exhaust side:
With friction drive like this, light cuts (I do 5 thou / 0.1mm) at a time and a very sharp toolbit is needed.
For the steam side cover, I left a bigger boss. You might notice that the workpiece slipped a bit relative to the chuck jaws; that happened when I was machining on the boss rim and the cut got a bit heavy. When things started slipping, I just backed off a bit, and fed back in more gently to finish off:
One luxury about normally being the only person going in my shop is that I know I can leave my machines in a "known state". The mill and vise back-stop was still set up from last week's machining, as was the DRO, so it was a quick job to set up the steam cover again and drill out he center hole and add the flange bolt-holes which I forgot to do last weekend:
The rest of my shop session today wasn't picture-worthy, but it was good
. Besides the stock I bought, I also bought a new set of M2 taps, and for the rest of the shop session, I applied those, as well as the M3 taps. I finished tapping
all the holes in the cylinder block with no drama, but it took quite a while. It's nice when one can start mock-screwing bits together; there are studs and nuts needed though:
I'm quite disgusted with myself
. When I drilled the holes in the cross-head flange, I was a bit off for some reason
- the bolt pattern is a bit tight, so I'll have to use some judicious filing in the holes on the flange to make things match more smoothly.
That bit of cast-iron will tax my machines to the limit... It actually fits over my 4 jaw chuck, and there might just about be enough room over the lathe-bed to machine it:
I need to cut a slice off it... After checking, that may just be possible on my "too small"' band saw. Things might get interesting soon. I'm promising nowt though.
Kind regards, Arnold
Kind regards, Arnold
