Jewellery

After I coughed a few times and put on a long face I was granted a day pass to work on my Z20 today. The labrador has another 3 weeks before she’s due so the whelping box can wait a couple more days. What I wanted to achieve by the end of my modelling time today was to have the three parts I was working on (the two sand or oil boxes and the brake cylinder) made and bolted to the side of the chassis. I’ve managed that and the photo that accompanies this post illustrates this stage.

The distinction between the two brass shapes bolted onto the side of the chassis is very clear in this photo. The one on the left was primarily made on my mill, the one of the right on the lathe.

I cut the boxes in half (I’ve sort of come around to the idea that these boxes are actually for a lubricant, the feed line exiting the bottom looks too small for sand in my opinion) and got them bolted on last night so today it was time to take the big step and make the brake cylinder on my lathe. I’ve owned my little Sherline lathe for a couple of years now but I haven’t actually used it. Personal circumstances and a new job put paid to my plans regarding how I was going to use this machine, but nothing seems to prompt the use of machines like these so much as a project: you don’t just make “parts” in a vacuum, you only start to make use of the machine when you have a project. Scratch building a locomotive or a piece of rolling stock is a perfect excuse to use a mill or lathe.

The lathe has been sitting on a lower shelf on the work table I have in the garage so I lifted it and placed it on the table top, after I’d cleared it of 18 months of accumulated junk of course! 🙂 These lathes are small but perfectly formed and they are a quality product. Even to my untutored senses I can tell they are a superior product to the cheap mill I own. As is usual with me, I spent about 2 hours fiddling about with a component on the lathe and drawing a plan until I finally decided it might be a worthwhile exercise to actually trying turning some metal. I cut a 25mm long chunk of brass from a length of round bar I’d purchased a couple of weeks ago and got turning. I faced off one end (I love that kinda talk 🙂 ) and shaved the section down until I got it to the shape you can see in the photo. I then milled off a very small flat spot on the rear side and drilled and tapped a 12BA hole which accepts a 1/4″ long brass bolt passed through a hole I drilled in the chassis. I also fixed a mistake I’d made in soldering the spacer you can see in the photo in the rear, so all in all this was a very productive day.

I’d give myself 6/10 for this little part. I did plan it out but I lack the skills to get it perfect and managed to cut the ring at the base of the cylinder a bit undersized. By the time I’d discovered the mistake I’d already removed the scrap I’d used to hold it at one end so it was much too dangerous to make any changes. It means I don’t really have enough of a “ledge ” to add the bolt head detail that can be seen in the prototype photo I posted last time. This bugs me but not enough to make me go back and make a new one 🙂 I’ve already checked the swing of the bogie and it clears this hanging piece of jewellery, so everything is sweet.

The next steps will be the application of brake shoes, angle braces, some detail around these shapes and quite a bit of pipe work. After this is all done I’ll probably paint the chassis with a basic black coat and then apply pickups and put the wheels and motor back on. And of course I still have to make the leading pony truck.