Micro-Sized Miniature Lathe

This is a tiny lathe I made last weekend. The motor is from a small hand vacuum motor and is directly attached to the chuck. It won't work with wood, but foam composite from a sign making shop works great.

The power supply is from an old mini radio TV. I believe it's 12 volts and .85 amps. The case is made from scrap Plexiglas, which I get for free from the same shop I get the sign composite from. The fancy on-off switch was attached to the motor when I got it.

Everything is stuck together with JB weld and Loctite super glue ( I swear by this stuff).

This whole project cost me nothing but time, a bit of solder, JB weld, and Loctite. All-in-all about $1.00 worth of bought materials.

It turns very fast. Great for making small wine glass shapes, chess pieces, and barrel shapes from foam composite.

I hope you enjoy the video and slides!

Centering

Finishing up

EDIT This project was so easy, I've decided to make an 'ible for this... I will be using a tape player motor because those are easy to get and will work better than anything of the same size.

Comments

[Dumchicken]

i was just wondering is your screwdriver grinded up?

[nepheron]

Nope, the screwdriver is fine :)

[Dumchicken]

thats good to know

[Dumchicken]

o and the other cup fell over :) :) :) :) :) :)

[playmoboy]

Whens the 'ible comming?

[nepheron]

It already exists! :)
http://www.youtube.com/watch?v=JK9iwXN-5AI

[steliart]

For a miniature lathe this is great. Very well done

[imthatguy1125]

Heres minewww.instructables.com/id/Mini-Foam-Lathe/

[omnibot]

That's pretty cool. I've been considering a similar idea but with a cordless drill-motor, the motorcontrol is promising and the gearing should give more torque.

[imthatguy1125]

 This is awesome, do you think a rc car motor would work

[nepheron]

 It depends on the torque. Power it up, and see how much force it takes to stop the shaft from spinning. Try it!

[imthatguy1125]

 Tried it works ok but for some reason the foam wobbles really bad

[nepheron]

Hmmm...

Sounds like the foam is not anchored on the shaft properly. If it wobbles, then the foam is able to move. Your foam may be too long or not secured to the motor shaft enough.

[imthatguy1125]

 Well it was hot glued on and I was using blue insulation foam, I tried florist foam but it was soft and rotting, thats probally because it was 2 years old, the insulation foam stops the motor so I need a stronger motor, I might just buy a cheap drill off ebay though 

[nepheron]

Before you buy a drill, try using some new floral foam. Just to see if it works :)

[imthatguy1125]

 tried it, works better but the foam had tiny holes in it(they were there before I tested it) Ill post some pics later

[lieuwe]

i built one, but i couldn't get it to stay on there, so i used hot glue, works like a charm, but how do you get your foam so smooth? when i stop turning it has holes all over the place, might be my foam tho...

[nepheron]

Ok, rough foam is cuased by using a sharp tool. Are you using some kind of knife or blade? Foams gets smooth when the material is ground away. The very best tool that I have found for making smooth foam is a tiny flathead screwdriver.

Cutting tools will only lead to a "pocked" surface.
Blunt headed tools result in a smooth surface!

[lieuwe]

 i used the exact same flathead as you, could it be the turning direction? does it have to turn towards you or away from you? and getting the foam into a cylinder takes a long time... i might experiment with hot screwdrivers sometime soon...

[nepheron]

Also, try cutting slowly. If I cut into the material too fast I get a rough, pocked surface.

[nepheron]

in  this particular model the spindle is turns away from me. That's also important for smooth foam becuase the screwdriver won't "bite" into the foam.

[lieuwe]

 that's probably my problem :-) i'm gonna retry this soon... any ideas on how to prevent the scraps from dumping on the floor/table?

[nepheron]

No....... The fine particles are impossible to catch without a vacuum...

[shawntherobot]

what happens if you try to use wood? And also where do you get that foam.

[nepheron]

I have not actually tried wood, but It would probably just spin off the chuck or bend it. The foam composite is from a sign/product display making shop. Find one in your area and you may have a great source of free foam and plexi scraps.

If you can't find that kind of foam, that green floral foam should work fine.

[lieuwe]

wow, that's small, my hands aren't nearly steady enough for this, on question tho, how do you get your piece centered so nicely? every attempt I've made at a homemade lathe results in a piece off foam flying across the room :-/

[nepheron]

Do you have a 'dead center'? My lathe is so small, I don't need a dead center if my piece is no longer than 3 cm. Also, my chuck is simply a metal fork that sticks into the material. Proportionally it goes quite deep... that means high stability. Another reason this works so well is that the foam composite I carve has a very low density. It's light enough and flexible enough so that it doesn't have a lot of weight to "throw around" and break off. I hope you get your machine working :)

[Goodhart]

I was thinking the same thing.....That an equal mechanism on the opposite end without a motor attached, might help. But I don't see one here.

[nepheron]

My piece of foam is less than 3 cm in length. I don't need a dead center for this, but that's just the way my lathe happens to work *shrug* .

[lieuwe]

exactly, my problem always is that when it starts a tiny bit off centre the whole thing flies apart...

[Goodhart]

I just took another look at the slide show......I still don't see how something could be held precisely in the center while spinning at those speeds, and while cutting. The lack of materials to build this with and such make me a bit suspicious of the whole thing. This would make a GREAT -ible, if they wanted to demonstrate how to build one.....but then, maybe they are afraid of duplication? Or that this really is not what is seems maybe?

[nepheron]

Here is a cross section. It's very basic.

[nepheron]

I have a video of how I center the block. Would you like to see it? Lathes are the simplest type of machine tools ever invented. The high accuracy is achieved by the spinning and not the eye-balling of a human being. I could make an 'ible, but I only had one motor and I wasn't sure it would even work when I started.

[Goodhart]

Yes, I would be interested in seeing the video, if you don't mind. :-) It bothers me that I am having difficulties in imagining a block of wood on a to prong fork whirling about at high speed and not flying off as soon as it is touched.

[nepheron]

I know what you mean. I couldn't see it until i was finished and actually used it. The video is uploaded. It's the the first video on this page now.

[Goodhart]

Thanks. Amazing. I am sorry if any of my posts sounded a bit harsh....I have been having a really horrible month so far (no excuse though).

And now, I also know what you mean by the motor is just from a hand vac (vacuum as in cleaner....pain meds do not help one think clearly....).

Very nice.....I will have to put this on my list of things to do :-) Thanks for being patient with an old codger ;-)

[nepheron]

Ok. the HQ video takes about 45 minutes to upload (!!) so check back in an hour or so.

[nepheron]

It self centers. I start with a rectangular block and turn it into a cylinder.

[rimar2000]

Very good! These small wine glass shapes they are beautiful!

[nepheron]

Thanks!