Using a drill as a lathe for working putty?

[Major_Gilbear]

So, er, after a slow day at work and some modelling-related thinking, I was wondering if anybody had used a household electric drill as a lathe, and whether it worked very well or not?

I have been thinking about ways to make shells, missiles, torpedoes, etc., and the best plan to get them nice and even would be to lathe them. My initial thought was to put a roughly cylindrical lump of Milliput onto a length of brass rod (crimped a bit first so the putty doesn't shear) and letting it cure before slotting it into an electric drill and tooling it with a blade/sandpaper/file.

However, if I loosen the Milliput with a little water first, and then use my non-stick silicone tools, could I stick it in the drill at a low-ish speed and work the stuff whilst wet do you think? Sorta like clay on a potter's wheel?

Any thoughts, tales or experiences on the matter would be appreciated!  

[Christian]

I'm not sure... sounds a bit rough to use with putty. On plastics and brass it shouldn't be a problem.

I saw someone painting a very even stripe around some missiles using this method.

[SBRPearce]

How precise is your speed control on the drill? Unless it's got an extremely sensitive lower range, I think trying the potter's wheel with wet Milliput is asking for putty slinging all over the shop.

OTOH, running a cured piece lathe-fashion with files and fine sandpaper is ideal for radially-symmetrical items. I used brass rod chucked into a Dremel tool to make a beautiful 1:35 scale baseball bat some time ago - the same technique would do well for rockets, missiles, Panzerfausts, etc.

Show us the results!

[Major_Gilbear]

Well, I had a go at this last night after dinner.

I got a length of 2mm brass rod (2" / 50mm or so) and kinked the very end. Mixed up a 1" / 25mm ball of yellow-grey Milliput and put it onto the end of the brass rod that I'd kinked. It was shaped into a little cylinder and I tried to get it fairly even and centred. About half the brass rod remained sticking out of one end.

After it had had an hour to cure, I suspended it in a mug of boiling water. This speed-cures the Milliput, and allowed me to try out my plan in that same evening.

Once it was cured and I'd dried it, the test piece was fitted into my drill chuck. The drill is a cheapo one which has crude variable speed - faster as you depress the trigger, and then full speed once the trigger is fully depressed.

I used a steep angle Xacto blade, a file and some coarse sandpaper on a stiff backing as my test tools.

Overall, the process did work as well as I'd hoped. I did learn some things though:

1 ) Despite being thick brass rod, there was a little flex in it still.

2 ) The putty cylinder wasn't really centred well enough or even cylindrical enough. No biggie, but it did mean more work to machine it.

3 ) The knife didn't work. The cutting face and the angle was totally wrong. Obvious really, but I still thought it would make some sort of mark.

4 ) The sandpaper worked well, and smoothed the cylinder out quickly. The paper does gum up though, so I don't know how well it would have worked if it had been a finer grade.

5 ) The file worked best, but was a fine modelling file, and gummed up quickly.

6 ) I didn't have a rasp or saw blade handy, but I imagine they would have been more effective if somewhat coarser than the modelling file.

7 )  Although it machines well enough, fully-cured Milliput is remarkably hard!

8 ) You really do need somewhere that you can firmly secure the drill to / against. A table vice would be ideal I think. I didn't have one and relied on my own body weight and strength of arm (!) to hold it firmly against the table instead. That is a less than ideal option, but it worked well enough for my test.

The final lathed test piece of putty is not really useful for anything, as the learning experiences meant that the first effort produced a poor piece.

Still, I think it would work very well for making shells, missiles,  rockets and things with simple shapes. I think it would take a lot more work and experience to produce barrels or anything with more complex detail though.

If a softer material was used (perhaps like resin or hard styrene), I think the technique would work better still. This is because you'd need to apply less tool pressure to shape the material, and that would mean points (1) and (8 ) above would have been less important. It would also mean that more tools would mark the material and give you more choice.

[Mindenbrush]

Normally when turning a cylinder on a lathe the opposite end of the cylinder has a free running centre to stop it deflecting, it would take a lot to set this up using a simple drill and you would need a free running chuck when using rod. Brass rod is likely to deflect more easily than a steel rod.

 

[aircav]

I used a dremel to turn down plastic rod for the guns on my K-Wagen
http://leadadventureforum.com/index.php?topic=13827.45

I put the rod in the chuck put the dremel in a vice and used a stanley knife blade to turn it down 

[dampfpanzerwagon]

Check out this post;
http://dampfpanzerwagon.blogspot.com/2010/06/modelling-lathe.html

The lathe attachment was bought from a clearance store - less than £20.00, the drill is a cheap PowerDevil (really cheap) BUT it works and for what you are talking about could be the perfect answer

Tony

[Connectamabob]

I made a master for a bunch of resin cannons once by chucking some aluminum rod in a drill press and lathing it that way. Files and saw blades were my cutting tools of choice. I found that a saw is much easier to hold and control than a knife or chisel-type tool. Also it doesn't skip, because the teeth create a kind of natural pinioning balance when rested against the curve of the piece. If I had to do it again I'd use brass though. Brass is harder to cut, but aluminum is very "gummy": it clogs up the tools a lot more, and is harder to polish smooth. I still have a bunch of those cannon castings in a baggie somewhere.

I've also made replacement sword blades with my Dremel by lathing brass rod to a blade profile, then putting it in a pin vice and flattening it out with a sanding disk bit, and adding the bevels with a needle file.

I tried making wine bottles out of leftover clear plastic sprue once, but I kept getting overzealous and melting the plastic. IMO it should still be entirely doable, I just mucked it up with my poor discipline.