Adding a brake to a clutched roundhead colchester lathe

I recently sold my old colchester roundhead student which started the motor directly when lifting the starting lever and upon dropping the lever it switched off the motor and allowed the spindle to coast to a stop however if you wanted it to stop quicker you could press down on the lever it applied a brake..very usefull if you are in a rush when a large 4 jaw chuck is mounted with a large lump of steel in it.

My new lathe came fitted witha matrix clutch which is great...only starting the motor once a session...but no brake with a clutch model..

So I bought a secondhand bicycle disc brake caliper made a disc out of stainless plate 2.5mm thick mounted that to a carrier and grub screwed with dogged screws onto the lathe spindle...mounted the caliper onto 2 studs tapped into the gearbox casting and it works great.

I was going to use a cable to remotely operate the caliper but after mounting I tried it out with just a bolt in the actuating arm and thought ..just a hole in the panel with a knob on the shaft and it'll do

I hope the pictures are self explanatory

Nice job.

A good short project to write up for MEW with clear drawings dimensions and "why I did it this way". Although its unlikely that there are more than a few readers wanting to fit it to that specific machine its of general interest as there are a goodly number of lathes which would be improved by the device. Its much easier to modify a published design to fit a different machine; probably mostly changing hole sizes, positions and bracket shapes; than it is to work out a design from a clean sheet of paper. I'll bet there are more than a few readers who'd like such a device but either lack the skills / confidence to start from scratch or consider the reward not worth the effort.

Be interesting, albeit impossible, to know how the ratio of MEW projects, in the widest possible definition, pans out between made to design, minor modifications e.g. threads & fasteners, somewhat altered e.g. use whats in my handy box, seriously re-jigged, inspried by and stolen that good idea for something completely different.

Hafta admit that, apart from the optical tool height gauge, I'm pure thief.

Clive

Edited By Clive Foster on 09/09/2014 18:21:16

Edited By Clive Foster on 09/09/2014 18:22:03

Clive

I'm not sure that its worthy of an article mainly because every lathe other than a round head colchester will be different.

I posted this just to show other owners of clutched colchesters that a brake was possible with the small amount of room available

The brake caliper is very powerfull and just needs a small amount of pressure to stop the spindle very quickly

I suppose a pedal bike with a large chap on it at 30 mph has large amounts of energy to shed with 2 small discs so a lathe spindle is easy for it

Ian

Edited By Ian Parkin on 10/09/2014 09:20:28

It's worthy of an article, not least because it demonstrates a principle which will be new to most, if not all, readers. Also, such brakes have other applications, so information on how to 'recycle' one is useful.

Neil

Ian,

Well thought out and executed.

Clive and Neil are correct, in that modifying an existing design is so much easier compared to figuring it out from scratch.

As an example, I've based my lathe power feed on a method of powering a mill table on 'mikesworkshop' website, by taking his design and adapting it for my use, thus saving me using grey matter and time I can least afford

Thanks Mike.

Geoff - GD gets a talking to when I see her next!