I was recently marking out a part to be machined using my version of a surface plate namely an old piece of plate glass. I have had this for ages and it normally sits unused in a dusty corner of the workshop (actually all the corners are probably dusty and some with added cobwebs). I was having particular difficulty seeing the the surface due to reflected light and the transparency and once I had finished decided to look at buying a new surface plate. I was surprised to find that small granite surface plates can be obtained at quite reasonable prices. For example Axminster provide a 300mm x 200mm granite plate for about £40.00. If however you want a real precision job a Mitutoyo plate the same size can be had for £234.00.
However as this would probably end up sitting in the same corner of the workshop and only be used on rare occasions I decided to investigate alternatives. I have read in a few places that bits of granite kitchen worktop can be used to good effect and also that Tesco, Argos and the like, sell small granite worktop savers at reasonable prices.
As I happened to be passing Argos I went in and found a 400mm x 300mm granite worktop saver for £8.00. At that price it had to be worth a go and if nothing else would be big enough to tape a sheet of abrasive paper to for flatening plane irons and similar jobs. Once home and unpacked I cleaned it up and checked it with a couple of straight edges. There appear to be no obvious highs or lows and the surface appears evenly ground and polished. I think with my limited ability to test for flatness it will suit my skill level and suffice until I need something more accurate. The only minor downside is that it is very shiny, I think a matt finish is normal on surface plate. I may be able to cut the glare with some abrasive cleaner but that could make it less flat.
The leadscrew gearbox was getting a bit low on oil and as the oil was still the original I decided an oil change was in order. Nothing too complicated but it led on to another small mod to the lathe which I wrote up for anyone who needs new oil.
Maurice Duckworth contacted me from Cumbria with an interesting modification to the four bolt clamp plate for the WM250 lathe. The main benefit of which is an easily readable protractor scale for setting over the topslide. Maurice engraved the scale on the lathe without using a rotary table or dividing plate and his method could readily be used in the production of any type of dial or scale.
Also included in Maurice’s e-mail was an ingenious method to disengage and thereby silence the leadscrew change gear train. Included in this project was a description of how to make professional looking labels.
Without further ado I contacted Maurice and he sent me the necessary photos, text and permission to publish .
I wanted a smaller toolmakers clamp so made a couple. Not so much a project more of a “projette”. I thought I would document the making and add it to the site. I think it took longer to write the web page than it did to make the clamps.
Anyway these clamps are always useful and easy to make. I made some at school – about 50 years ago – and they are still going strong.
This is a modification I should have made years ago. At long last I have relegated the spanner to the drawer with it’s companions.
I have detailed how to modify the lathe tailstock to get rid of the old nut and bolt and replace it with a lever and cam – much better. This mod involves milling a pocket and drilling holes in the tailstock, so probably not something to do if the lathe is still under warranty. Of course lucky owners of the latest model WM250 already have this as standard. I have included some drawings which of are based on my lathe but could be easily adapted to other similar Chinese lathes, probably even the multitude of mini-lathes out there.
Whilst tidying up I moved the computer and managed to break the wireless dongle for the keyboard and mouse. I only have a small fold down desk in the workshop and a full size keyboard covers nearly all of it. I found a replacement mini keyboard and mouse set from Maplins – Cerulian Mini Deskset ref:N69JX.
This deskset comes with a mini dongle that only sticks out about 6mm so I shouldn’t be able to snap it off like the old one! The keyboard has quite a nice action and takes up very little desk space so should be fine for the small amount of use it will get in the workshop. As an added benefit it comes with a thin moulded silicone plastic cover, which I assume is packing, but will serve very nicely as an oil proof membrane as it is sufficiently transparent to see the keys through and very flexible. The mouse has a power saving feature and powers down after a few minutes of being idle, just click to wake it up.
UPDATE April 2015 – I bought another of these for use with my desktop computer, I notice that Maplins now sell it under their own name. With more use I have noticed that if you don’t hit the keys centrally sometimes a key will stick slightly, this doesn’t bother me particularly but a typist would probably find it annoying. I also tried it out with my so called “smart tv” it works OK but the range is not really more than about 2 metres for a reliable connection.