Monday, 28 October 2013

Messing about with my Unimat SL.

I've been messing about with my Unimat SL. Its obviously been looked after by someone who appreciates it but who has only used it as lathe. I know this because the power switch has been replaced at some point, it should have a lamp style in-line switch on the power cord, that had been replaced by a fixed switch attached to the rear of the wooden base, the wire from the motor to the switch running through a drilled hole in the rear of the wood;
Fixed switch on rear of base.

Cable running from motor through to switch.
This makes it impossible to reconfigure it as a mill/drill, and makes it difficult for turning tapers, taper turning being achieved by swivelling the headstock  which would have been difficult with the wiring preventing any degree of movement (on a larger machine a compound slide, which could be set at an angle, would be fitted above the cross slide). So I've fitted a new lamp style switch, and I must thank Frank for his advice, he's an electrical engineer and all round good egg. Nice one Frank, I owe you a pint!

Headstock set at an angle for taper turning, exaggerated.
Set up as a mill/drill.
I've also moved the lamp further to the right, it would get in the way when the machine is set up as a mill otherwise. I might just move it again, raising it up slightly.

The tailstock clamping set screw had been replaced by a usefull plastic lever, however I found it a bit ungainly and it made the tailstock difficult to remove so I've gone back to a set screw;
Tailstock clamp lever...

...replaced by a set screw.
Another thing to note is that the original toolpost has been replaced by a 4 tool turret designed for the larger Unimat 3. This would have been an indexing type, but to fit it to the SL the indexing bottom plate has been left off and I suspect that the bottom of the turret has been machined down to make it fit. However, its a very usefull addition. At the moment it has a turning tool and parting tool set up in it.

The machine is starting to feel like mine now, I have turned a couple of parts on it, but thats for another post.

Paul.

Thursday, 10 October 2013

Saltford Simplexes.

Saltford Models were a company that used to make some very interesting narrow gauge loco and wagon kits in OO9 and SM32.  The man behind this little cottage industry was Brian Clarke, a very talented modeller who had a collection of 2' gauge stock in his garden in Bath, including a Simplex, a Ruston, an Orenstein & Koppel and a Lister. Brian hosted several 'Small Engine Rallies' where he opened up his garden railways (full size and 16mm) to interested modellers. Brian was also interested in mine exploration and I accompanied him down several Bath stone mines many years ago.

The OO9 locos were pretty unique at the time as they came complete with motor, wheels etc at a time when most OO9 kits were made solely from whitemetal and were designed to fit onto RTR N gauge chassis. Brian's kits utilised the 'split frame' pick-up system, whereby conventional wiper pick-ups are not used, the current being carried to the motor from the wheels through the metal frames. This means that the sides of the chassis have to be electrically insulated from each other as are the solid metal wheels. Stub axles on the wheels fit into insulated muffs, which also take care of the back to back setting. The footplate was cut from plasticard, side frames simply being glued to the footplate in most cases. The motor was glued (yes really!) onto the footplate and sat in the cab space. There were variations of course (such as a DeWinton with the motor in the boiler), but thats how the two most popular kits, the Simplex and a freelance 0-4-0 Peckett, were designed.

I've built 4 Saltford Simplexes. The first 3 were built around 1988/89 and were used on a small layout that I owned. A few years later I built another with extra detailing.

Here's the second loco built, number 11 (click on the photo for a larger image);


Built pretty much as it came but with added sandboxes on the front and a piece of chain on the footplate.
Number 12 came next;


This one has had the cab lowered by 1mm, an exhaust added and behind the exhaust sits a bottom hose for the radiator. Here's the other side of 11 and 12, note the tissue paper tarp on 12 hiding the motor;


A Dapol workman gives an idea of size. The kit was designed around the motor and scales out at around 5mm to the foot.
Number 10, my first Simplex and possibly my first ever loco kit, has had some kind of accident;


This gives an idea of the design, note the two whitemetal sideframes, plasticard footplate (its not supposed to be in 3 pieces!), and wheels seperated by insulated muffs. The bonnet and cab are heavy whitemetal castings, which meant that the loco was rear heavy. This loco is due for a rebuild soon, when I'll be replacing the motor with a Mashima 1015.
And finally the later build, still not painted;


Brian turned the wheels, muffs etc. and did most if not all of the casting himself. The kits came with a piece of plasticard and you were expected to cut it to size and mark out and drill the footplate, bufferbeams etc. yourself. Drive on this kit, and on the Peckett, was to the rear wheels only. It is possible to use a Nigel Lawton driveband to couple both wheels together, this needs to be done as the loco is being built.

Paul.

Sunday, 6 October 2013

Unimat SL.

Today I've bought myself a new tool in the shape of a Unimat SL. This is a small hobby sized lathe which can be easily converted to a vertical mill. Other attachments allow it to be used as a jigsaw, fretsaw, grinder etc.
This one has been bolted to a smart wooden workstation with a lamp attached;


Note the tin of Humbrol, to give an idea of size.
Here's the post and bed, used to convert the machine into a mill, and a couple of clamps and spare lathe toolpost;



More parts, spare drive belts, oil, faceplate, centre, drive dog;


The original manual was included, along with a usefull looking book (on the left);


And finally a new set of turning tools;


Also included but not shown are the chuck keys etc. and a couple of other turning tools.

I haven't tried it out yet, but it looks like a well looked after machine which I'm sure will be usefull to me.
I'm actually a skilled turner, I spent 19 years working in various machine shops, but I haven't touched a lathe in about 7 years. Despite my experience using this machine will be a learning curve, being a lot smaller than the machines that I worked on before, the smallest of which was a Harrison M300 (which most hobbyists would find huge). Mostly I worked on Harrison M500 (nice) / Colchester Mascot 2000 (shite) sized machines, although I sometimes worked on larger lathes. At the time I hated turning anything under 40mm diameter, prefering to get my teeth into a nice big billet of EN3 or similar, so using such a tiny machine will I'm sure seem odd!

Paul.