Lathe Chuck Brake

[LMMasterMariner]

Hello again,

Another modification of my lathe (11 x 26, big brother of Grizzly G0602).

Made lathe chuck brake using motorcycle rear foot brake.

Very useful for threading if you don't disengage half-nut lever like me.
I never use threading dial, even I have it.
It can be also very useful in case of emergency when instant stop of chuck rotation
is needed. As you can see in video clip it stops chuck rotation from 2022 RPM in no time.

As chuck is screwed on and in order not to unscrew when stopped instantly, I decided to
mount brake at chuck and not on motor spindle or elsewhere. Just to be on safe side,
even there are 2 stop screws at chuck back plate, which should prevent chuck from unscrewing.

I uploaded video of that brake at youtube:

Thanks for watching.

This is lathe hand brake and it can easily be converted to foot brake, but I have
drawers cabinet underneath, so foot brake is out of question.

Two things are happening by pulling brake handle;
1. stopping electric motor using safety switch at chuck guard shaft
2. braking

Used dirt bike foot rear brake. Bought complete brake; caliper, master cylinder, hose and disc
at Taobao for less than USD 15.
https://world.taobao.com/item/539966....SBmdl9#detail

Picture 1 / Lathe Chuck Brake

Picture 2 / Brake complete for 250 cc motorbike
It can be found at ebay or aliexpress.

There is no need to buy disc as there is no room for brake caliper if original disc is mounted behind chuck back plate.
So, I also fabricated new disc. Made it from 25 mm high tensile AH36 (shipbuilding) steel plate.
It is covering chuck from behind and there is additional distance which enable this floating type motorbike
caliper to fit in.

Picture 3 / Fabricated Brake Disc drawing

Picture 4 / Lathe chuck upside down with back plate up

Picture 5 / Brake disc (also indexing) mounted on chuck back plate

Picture 6 / Small parts

Picture 7 / Base. Made of square SS bar 35 x 35 mm and mounted on the ways in the same
way as follower rest. Used under way part of follower rest to fix it on the ways.
There are no additional holes on the lathe.
CORRECTION: STEADY REST, NOT FOLLOWER REST.
======================================

Picture 8 / Throttle Cable which is laid under the ways and coming from behind the splash guard.
It is used to stop electric motor. Connected to chuck guard shaft / safety switch.

Will upload another video of assembling all these parts. Need 2 hands and must
persuade my wife to hold camera. That video will be named Stopping Small Lathe / Part 2.

Next completed project is indexing fixture for small lathe. Already done, but have no time
for another post right now.

Regards
LMMasterMariner

[DIYer]

Thanks LMMasterMariner! We've added your Lathe Chuck Brake to our Lathe Accessories category,
as well as to your builder page: LMMasterMariner's Homemade Tools. Your receipt:

Lathe Chuck Brake by LMMasterMariner

tags: brake, chuck

[Frank S]

I too have thought several times about a chuck brake for 1 of my Lablond lathes. and as your much smaller lathe than any of mine are 2 of them have a 2 7/8-5 spindle thread but with the short nose taper adapter to mount the chucks. Since my chucks are 12" in diameter adding a disk type braking setup would require a minimum of a 16" disk but I feel it would get in my way also the hundred lbs or so of rotating mass comprised of the spindle gears belts and motor might serve to drive the threads ever tighter making it impossible to remove the short nose adapter in order to mount my face plate which is threaded to fit the spindle.
There is a 10" diameter hand wheel made on the counter shaft that is there to use by hand to slow the lather to a stop or to rotate the spindle by hand. A brake system could be mounted there but like you I then would have concerns of the spindle nose loosening.
At this stage I am thinking that if I ever want good active braking on my lathe then I should wait until I can come up with a D1-6 cam lock spindle nose that can be mounted on the 2 7/8 by 5 thread and permanently lock it on the spindle then convert all of my chucks and face plate to that system then install a brake

[rossbotics]

Nicely built, great job, I must say that's the first breaking system I have seen used on a lathe that utilizes an automobile break caliper and rotor, excellent work

[LMMasterMariner]

Hello Frank,

Thanks for your comments and your idea of permanently locking back plate to spindle nose.
That idea did not cross my mind. Another reason why I put it on the chuck was indexing fixture.
Made two rows of holes on that disc, inner row with 24 holes and outer row with 30 holes.
Picture attached.
You can do it for your big lathe also, but you should use car brake caliper and thicker brake disc.

[LMMasterMariner]

Hello Doug,

Thanks for your comments.
This is actually motorbike brake caliper and it's good enough for lathe of this size.
I have seen car brake caliper and big disc mounted on electric motor shaft
of big Daewoo lathe. That brake was foot operated and it was capable of
stopping chuck rotation instantly at low revolutions, but at 1500 RPM it took
couple of revolutions until it stopped.

Regards
LMMM

[Frank S]

I agree I have used the wilwood MC4 mechanical calipers on 1 ton trucks for the parking brake application they can handle a disk up to .850" in thickness and the smaller Wilwood 120-1360 on many of my smaller elevators in conjunction with electromagnetic solenoids as a means to restrict float while the platform was being loaded and unloaded

[ncollar]

I've thought about a brake on my lathe and I was thinking about caliper style brakes but on the motor shaft. A little bit more eloquent.

[LMMasterMariner]

Hello Ncollar

Fully agree with you. It would also be more professional.
But I had couple of reasons why I put it on the chuck;
1. To prevent unscrewing of chuck.
2. To have indexing fixture.
3. To avoid additional drilling and new holes on my lathe (check my post Captain's Lathe Reverse Tumbler)
4. This was much easier to do.

[ncollar]

But we were talking about the brake. I would be nice to see a little bit more on the brake.
Nelson