Auxiliary fine feed for my minilathe

[stefang]

I never used the powerfeed via the leedscrew on my minilathe for turning, because i couldn't find any gearcombination thats slow enough to give a nice finish.

Today I decided to build a fine feed thats powered by a small geared dc motor:

The motor, 3000rpm@24V with a 50:1 gear with the coupling


The counterpart to the coupling, mounted on the leadscrew


A few holes and some tapping later, everything screwed together, and it looks like a fine feed


I hooked it up to a DC powersource and tested the fine feed on leaded steel, aluminum and drillrod, i always get a real fine and nice finish.

Stefan

 

[BobWarfield]

Nice rig!

I've seen fellas set one up on the back side of the cross slide to get a fine feed there too. Nice to twiddle a rheostat and change the feedrate without messing about with change gears. I do so little single pointing, I just loaded the slowest combo of gears and leave it be. However, as you've pointed out, even slower would give a finer finish, and faster would be nice for roughing.

Cheers,

BW

 

[shred]

My old 1930's 10" Sheldon lathe has a clever little 3-speed gearbox on the lead screw-- if you load the slowest set of gears, by moving the 3-speed box, you can shift the feed from .0125 to .0064 to .0031 per rev which works pretty well for roughing and finishing. Sort of a 1930's equivalent to the rheostat

 

[Foozer]

Nice rig!

I've seen fellas set one up on the back side of the cross slide to get a fine feed there too.
BW

On my little 109 turning that cross slide crank makes the fingers tired,cant keep an even pace, get rushed and break something, 'specially when the facing operation is in the 2 inch (50mm) range. Got one of those display table motors from Micro-Mark (2.5 RPM)
http://www.micromark.com/ANIMATION-GEARMOTOR,7886.html
stuck it on a simple bracket with a pin to act as me finger. I just clamp it to the bench top and have some coffee while it go round and round. Must have a high impedance to it as no heat up occurs should it reach the end of travel.

 

[Kermit]

Nice idea.

And as I remember....the carousel in microwave ovens uses just such a slow speed motor. Only a few billion of the things around the planet. maybe I'll find one??



(Kermit adds another item to his list of things TO DO)

 

[Andrewinpopayan]

I have used these motor / gearbox combinations on *many* projects. They seem to date back years and are used in many electro-domestics that require a slowly rotating shaft, stuff like washer timers, rotissiere, microwave plare turners1001 uses. The greatest number are made by CROUZET and are avaiable in 115 and 240 volt AC. The motors are "snap fit" with a retaining clip, so can be changed easily, the gearboxes are available in an almost infinite variety of ratio's. There are 2 wire motors (single direction) and 4 wire (reversible). The Sanyo range of stepper motors also fit onto these gearboxes.

There are usually plenty for sale on *bay, here is the makers website. WWW.CROUZET.COM

 

[Kermit]

Dug through some junk at work and found these (3 of them). Tested them out and they all work,but one is a little noisy, lube may have dried up in that one.

Sing me a song,
Kermit

 

[Davyboy]

Yes, I have the same frustrations with my HF 7X10. I like what stefang did with his. It looks like a good design. I came up with an old sewing machine from a yard sale for only one dollar. I plan to (someday : ) use that motor as a variable lead screw drive. I need a little better speed controller ( rheostat ) but that's the plan. Thanks Stefang for filling in a few details.

DB

 

[Andrewinpopayan]

now these motors would be ideal for anyone wanting to mod thier feeds, they are reversable.

Item 350174933361 on fleabay.

 

[ken4570]

I coupled a windshield motor to the lead screw.
Plenty of torque, Wired to a PWM speed control, very slow speeds