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G.A. Ewen
11-05-2004, 11:27 PM
Has anyone here done any free hand turning?

Is it limited to brass and aluminum or can you do it to steel also?

wierdscience
11-05-2004, 11:52 PM
Yes you can do steel too,I have done plenty of brass and aluminum while making wax casting masters.
Before lathes were fitted with change gears and leadscrews machinists used hand cut chasing rings and tools.Also the term "Threads" originated from wrapping a string around the shaft to be threaded,bluing over it,removing the string and following the helix it generated with a handheld tool.

BillH
11-06-2004, 12:13 AM
chatter wasnt a problem?

G.A. Ewen
11-06-2004, 12:13 AM
Darin,
What advise can you give someone who has never done it?

CCWKen
11-06-2004, 12:32 AM
By freehand, are you saying like that done on a wood lathe? Some sort of tool rest would be needed, wouldn't it? Shallow cuts or a four foot tool.

mochinist
11-06-2004, 01:28 AM
"What advise can you give someone who has never done it?"


Be Careful

G.A. Ewen
11-06-2004, 01:29 AM
<font face="Verdana, Arial" size="2">Originally posted by CCWKen:
By freehand, are you saying like that done on a wood lathe? Some sort of tool rest would be needed, wouldn't it? Shallow cuts or a four foot tool.</font>

Yes, I have a project in mind that will require some odd shapes on small diameter work.

tattoomike68
11-06-2004, 01:38 AM
I built a 40" face plate for a wood lathe in a foundry pattern shop.

It was about 100 lbs but was solid as a rock(ave workpeice diameter was about 30")
I built it for the outboard side of the massive slideing gap bed wood lathe we used for wood.

pattern work can be bad, a part lagged with aluminum, eurothane,slow of fast cast, so you are machining through plastic,nails screws, aluminum and god knows what else all on the same part.

It is easy money just dont hog on it.

Techtchr
11-06-2004, 07:43 AM
I have turned mild steel "free hand" in my metal lathe. I roughed with conventional lathe tools then smoothed the cut with old but sharp woodworking lathe tools to smooth and finish the cut. I was turning 2" diameter stock and putting about a 1/2" radius groove around it. I could have used round files to finish, but this was faster.

Matt

JCHannum
11-06-2004, 08:45 AM
I have done it on smaller parts. I have an Aloris type toolpost. I used a heavy bar clamped in tool holder for a toolrest. You might want to bend at an angle to get closer to the work. I use a couple of old files ground to a radius for cutters. Longer handles would help.

Set the tool rest slightly below center, and you can adjust angle as you cut for the best geometry. I rough shape in the normal manner, and clean up by hand.

wierdscience
11-06-2004, 09:23 AM
George,best advice I can give follows that for woodturning.Keep the toolrest as close as possible to the work.
Make sure the edge of the toolrest is polished and slick so you can slide the tool along easy.
The toolrest bar should have the top edge angled back at about 10-15* so you can rock the tool back slightly without the tool pivoting on the back edge of the bar.The bar needs to be substantial,like 2x3/8" edge up and well supported if a long piece is being turned(greater than 4")

If the part is long,or has deep features like a )( then bend a toolrest to follow the finished profile and use the crosslide to advance the toolrest in as the work progresses.
Ideally you want to maintain the rest within 1/8-1/4" from the work so you can use a comfortable length tool say 18-20" long.And of course you want the tool cutting on center.
Other than that all I can say is maintain a firm grip on the tool,go slow till you get a feel for it and it really helps to have a half template cut out of brass or sheet metal so you can keep track of your progress.Work slow at first because it goes faster than you would think.

Oh,one more thing I forgot to mention,tool profile.Try to avoid tools that cut on the sides,they have a tendancy to try and roll over and twist in your hands.If you must use one thats side cutting put a T handle on the end to give better control.

[This message has been edited by wierdscience (edited 11-06-2004).]

Frank Ford
11-06-2004, 11:56 AM
I made myself a little tool rest like my old wood lathe had:

http://www.frets.com/FRETSPages/Machining/Tooling/ToolRest/toolrest.html

G.A. Ewen
11-06-2004, 05:39 PM
Thanks everyone.
Great photos Frank.

Paul Alciatore
11-07-2004, 01:15 AM
There's no end to what I learn here.

Good pix.

Paul A.

BillB
11-07-2004, 11:41 AM
I've freehanded a few quickie replacement handles in Al and brass. Chucked a piece of drill rod or drill blank in a QC tool holder for the rest, used a small scraper to turn. As others have mentioned, things can get touchy quickly when rest-to-work distance increases, as when turning radius on a handle.

To finish, I cover the ways for protection, run the speed all the way up, & use sandpaper strips to remove toolmarks.

BillB

G.A. Ewen
12-23-2004, 12:43 PM
Here are photos of the turning tool that I have just finished. I will use it for turning wood and I am going to try free hand turning metal. Besides the good tips that I recieved in this thread I was also sent some photo copied pages from "The Beginners Guide to the Lathe". These were sent to my all the way from Australia by Mr. Frank Sandes, Thats again Mr. Sandes.

Black Ash was used for the handle (I know someone will ask http://bbs.homeshopmachinist.net//biggrin.gif ) Overall lenght with tool bit is 19".

http://img.photobucket.com/albums/0603/GAEWEN/Tools%20and%20Machinery/4015376c.jpg

http://img.photobucket.com/albums/0603/GAEWEN/Tools%20and%20Machinery/4edefefb.jpg

http://img.photobucket.com/albums/0603/GAEWEN/Tools%20and%20Machinery/77bd0688.jpg

Evan
12-23-2004, 12:54 PM
Smooth. I like the use of the socket. I've always been a bit afraid to try this. I have this image of the tool digging in and ripping the handle from my hands, flying up and smashing the fluorecent lights above the lathe, all the bits of glass raining down and being thrown about the shop and the tool finally imbedding itself in my foot or skull. Other than that it sounds like fun http://bbs.homeshopmachinist.net//biggrin.gif

pete913
12-23-2004, 05:48 PM
I've never done it myself, but I remember seeing a description of it and some pictures in an old book on blacksmithing. They used a tee rest just like in a wood lathe, and forged tools with handles on them long enough so that the handle went up under their armpit.

2cooltool
12-23-2004, 07:06 PM
Try to use a round nose tool with a five degree front rake. It works great

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