# why NO turning metal on wood lathe



## klr650

My question is why shouldn't you, rather than how can you. 

I've read dozens of articles on this, as to how to, caveats to it, warnings, etc. but none of them ever really explained why it's a bad idea to begin with. The speed of the lathe is hinted at, okay, I understand that metal lathes turn slower than wood lathes (actually I'm not entirely positive that's true either - I distinctly remember the lathes in school shop turned pretty darn fast).

I'm asking just so that I can be clear. "Don't cut metal on a wood lathe." "Okay, I won't, but why? What's the danger?"


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## john lucas

You can turn non ferrous metals quite successfully with High speed steel tools on a wood lathe. I've tried turning steel using actual metal cutting tools and it's just too hard to control. Brass, Copper, aluminum, and other soft metals turn quite easily. You don't need slow speeds for these. Some people scrape the metal, I almost always use cutting actions. Regular HSS tools dull pretty quickly. I use the new particle metal tools that I get from www.thompsonlathetools.com They hold an edge way longer when cutting metal and quite a bit longer when cutting wood.


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## woodnthings

*There are 2 main reasons*

First is speed, the metal lathes have a dual range if not triple range speed set if geared, some are variable. Then there is a back gear, which reduces the speed further by about 8 or 10 to one. Metal must be cut a very specific speed based on the Machinists Handbook recommendations, for different materials and different diameters which effect the peripheral speeds. It's kind of a science. Wood lathes don't go anywhere near slowly enough and would dull and heat the cutting tool to red in a heartbeat.
Second, the forces against the cutting tool,resisting are far greater in metal than wood and the precision needed requires a secure tool rest, not a simple bar like on a wood lathe. It's a safety thing as well.
You can of course turn wood on a metal lathe, and I have frequently. It also has power feed down the length which is nice for turning a uniform dia cylinder.
Hopes that helps. :blink: bill


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## klr650

Well, but WHY not?
I read statements like this 

"Putting metal in a modern wood late is not a smart move and would suggest that you consider such moves very carefully."

and this

"You would be dicing(sic) with death if you tried to turn metal in a wood lathe."

I can only assume he meant DANCING, not dicing.

Is that pure hyperbole, or are they alluding to a very real danger?


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## wildwood

I have never turned anything but small amounts of brass and aluminum (tool handle ferules) on a wood lathe. Would never consider turning steel on a wood lathe because not sure could hold or control turning tool. Might be able to insult some steel with a scrapper on a wood lathe. 

 Watching steel cut on a machinist lathe cutters do not ride the bevel. Cutting tools fasten down in tool holder securely on a metal lathe. Cutting tool fed into steel by turning a wheel or computer aided software. Water oil mix cools steel and cutter during the process. 

Am not saying you cannot turn steel on a wood lathe, just question why you would want too!


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## klr650

wildwood said:


> I have never turned anything but small amounts of brass and aluminum (tool handle ferules) on a wood lathe. Would never consider turning steel on a wood lathe because not sure could hold or control turning tool. Might be able to insult some steel with a scrapper on a wood lathe.
> 
> Watching steel cut on a machinist lathe cutters do not ride the bevel. Cutting tools fasten down in tool holder securely on a metal lathe. Cutting tool fed into steel by turning a wheel or computer aided software. Water oil mix cools steel and cutter during the process.
> 
> Am not saying you cannot turn steel on a wood lathe, just question why you would want too!


Because not everyone has both types of lathes.


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## Dave Pannell

I've trued up a couple of aluminum pulleys, as well as rebored them, all with my wood lathe, and an oland tool with a metal cutting bit in it. My lathe does however have a REAL variable speed motor, where I can turn stuff slow.

No danger that I could see, even with steel (never tried, too hard). Anything but steel is doable on a wood lathe, imo. The tool bit in a metal lathe is secured completely, unlike a freehand tool. And even with aluminum, the tool bit still would produce a small "chatter", but was cleaned up well with a file while it was still spinning.


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## klr650

That's actually what I was planning on doing myself. I have a set of threaded rods that I need to file down in the middle and figured that my lathe would be perfect for that. Then I started poking around and ran into a bunch of comments about how it's dangerous and figured maybe I'd better ask first.

I don't exactly see a huge swell of people warning me against it, quite the opposite actually, so the heck with it - I'll give it a shot.


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## H. A. S.

klr650 said:


> Well, but WHY not?
> I read statements like this
> 
> "Putting metal in a modern wood late is not a smart move and would suggest that you consider such moves very carefully."
> 
> and this
> 
> "You would be dicing(sic) with death if you tried to turn metal in a wood lathe."
> 
> I can only assume he meant DANCING, not dicing.
> 
> Is that pure hyperbole, or are they alluding to a very real danger?






There is a lot of misinformation/lies on the Net. If you don't know what you're doing, tying your shoes could be dangerous.

My wife's 'Commander' wood lathe goes down to 106 RPMs, plenty slow enough to turn steel. May have to try that this summer. There are videos on the Net of a guy turning and drilling steel on his Shopsmith.

There is also a rumor about not turning wood on metal lathes, destroying the ways and bearings. WHAT?:icon_rolleyes::laughing:

Drop me a line if you need to know what can and can't be turned.


Just goes to show you, if a guy tells you that absolutely something cannot be done, he's probably lying or inexperienced. Very few hard and fast rules in wood and metalworking.

Mostly, it's the inexperienced part.


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## H. A. S.

klr650 said:


> That's actually what I was planning on doing myself. I have a set of threaded rods that I need to file down in the middle and figured that my lathe would be perfect for that. Then I started poking around and ran into a bunch of comments about how it's dangerous and figured maybe I'd better ask first.
> 
> I don't exactly see a huge swell of people warning me against it, quite the opposite actually, so the heck with it - I'll give it a shot.



I'm sure you know this already, but chuck up on the rod, so it's as close to the chuck as safely possible. Don't want too much sticking out. Sticks out too far, and it'll whip around and take off a few fingers, or worse.


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## GeorgeC

klr650 said:


> Well, but WHY not?
> I read statements like this
> 
> "Putting metal in a modern wood late is not a smart move and would suggest that you consider such moves very carefully."
> 
> and this
> 
> "You would be dicing(sic) with death if you tried to turn metal in a wood lathe."
> 
> I can only assume he meant DANCING, not dicing.
> 
> Is that pure hyperbole, or are they alluding to a very real danger?


Did you not read Woodnthings explanation?
. He gave a good description of why not.

George


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## woodnthings

*Filing and turning are completely different*



klr650 said:


> *why NO turning metal on wood lathe*
> 
> That's actually what I was planning on doing myself. I have a set of threaded rods that I need to *file down in the middle* and figured that my lathe would be perfect for that. Then I started poking around and ran into a bunch of comments about how it's dangerous and figured maybe I'd better ask first.
> 
> I don't exactly see a huge swell of people warning me against it, quite the opposite actually, so the heck with it - I'll give it a shot.


Had you asked that specific question right off my answer would have been fine, try it and run your lathe at the slowest speed, unknown, another useful bit of info that would have helped. "Turning" can be anything from making rims for your car, a rifle barrel, a ferrule for a lathe tool, "metal" can mean steel, brass, aluminum, etc. The answer you get depends on the specificity of the question, in other words. 
Filing down the center of a 1/2" rod, held in a 3 jaw chuck, supported on the far end by a center or bearing block, would have been fine. The file is not as aggressive as a hand held tool, which can dig in a jam and send it flying. ..or slip off that small diameter and cause your hands to contact the spinning rod...all sort of Murphy's Law possibilities, not to mention don't wear gloves or long sleeves.  bill


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## Terry V

*It can be done*

I have a metal turning lathe but do sometimes use my wood lathe for turning small bits of metal, including aluminium, brass and steel. I have made some quite chunky pieces in aluminium, and various small items in steel without problems. The traditional tool for steel is the graver.

I have put information about it on my "For other turners" page about half way down if anyone is interested. :smile:

Terry

http://www.turnedwoodenbowls.com/forotherturners.html


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## klr650

woodnthings said:


> Had you asked that specific question right off my answer would have been fine


Yeah I know, but asking very specific questions only gives you an answer that very often leaves you with more questions than answers.

But, you said something there that tends to corroborate the "Don't do it!" crowd - that is the tool digging into the material and getting flung back at you. Hadn't occurred to me, but that is a distinct possibility, and at the higher RPMs of a wood lathe that could be a pretty high speed. Although I never actually do wood turning without a face shield - so that would seem to be a pretty minimal risk.

In any event, if I find myself wanting or needing to do more than simple filing of metal rod, then I'm more inclined to simply buy a metal lathe - might as well get the right tool for the job rather than risk damaging my wood lathe (or myself!).


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## wildwood

If you told us what you planned on doing many of us would not bothered to respond. You can ruin a file using it incorrectly. Do you plan on mounting threaded rod on lathe and hand filing with lathe turn off or on? Hand filing no problem, could do same with rod mounted in a bench vice. Lathe on, heat buildup, file steel brittle, threaded rod pretty soft steel. 
People have been spinning metal on wood lathes for years. Never had an interest you need the right tools to get er done! 
Metal Spinning Workshop
http://www.metalspinningworkshop.com/convertwoodlathe.html
Sorby once sold metal spinning tools not sure where can buy them. 
Here are some hand-forged tools.
http://www.jamesriser.com/Machinery/Forging/ToolForging.html


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## woodnthings

*Maybe so...*

Quote: 
"Yeah I know, but asking very specific questions only gives you an answer that very often leaves you with more questions than answers."

But that's the whole point of a forum, back and forth narrowing it down until everyone has had their "say" and the discussion is pretty much complete. It's a conversation with a large time delay, you know?  bill

Regarding hand filing on a spinning metal rod or other metal ctlinder, I've done it pretty successfully, with no danger or harm to the tool. You can chalk your file to prevent clogging since that will happen readily. I've ruined a file or two on a metal piece that was harder than the file itself, but you find that out very readily also....skip...skip...:laughing:


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## klr650

It's a argument perhaps for another time, but in general I don't like simple questions because I find I rarely get anything from them. I'm not a mission oriented person, I want to know why rather than how (most of the time).

But to each his own and I certainly do appreciate those who have taken the time to respond. As for my file collection, I suspect that yes, I will be breaking a few before I figure out a good way to shave down metal rods on my lathe.


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## BWSmith

klr,see if this works.Am diggin around looking for Walker Turner "stuff" and this popped up.This isn't an endorsement........but iffin somebody had to do it,it would work for light cuts.I've been making parts for my W/T lathebed welding positioner;as such,am "right there" WRT the machining necessary blocks to attatch a crosslide.We have a cpl big honkin metal turnin lathes so this ain't about me doin it......just sayin.BW


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## trlambsr

*Help with turning small alum. pieces*



H. A. S. said:


> There is a lot of misinformation/lies on the Net. If you don't know what you're doing, tying your shoes could be dangerous.
> 
> My wife's 'Commander' wood lathe goes down to 106 RPMs, plenty slow enough to turn steel. May have to try that this summer. There are videos on the Net of a guy turning and drilling steel on his Shopsmith.
> 
> There is also a rumor about not turning wood on metal lathes, destroying the ways and bearings. WHAT?:icon_rolleyes::laughing:
> 
> Drop me a line if you need to know what can and can't be turned.
> 
> 
> Just goes to show you, if a guy tells you that absolutely something cannot be done, he's probably lying or inexperienced. Very few hard and fast rules in wood and metalworking.
> 
> Mostly, it's the inexperienced part.



I need help turning small Alum. pieces on my General 260
tr


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## Wayne Dyas

I would expect it would be fine to turn aluminum or brass on a wood lathe but I've always wondered about what repeatedly turning steel would do to the headstock on a wood lathe. I would expect the headstock on a metal lathe would be heavier duty than one on a wood lathe.


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## GeorgeC

error


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## hughie

*go for it*



> [Because not everyone has both types of lathes.


that still doesn't make it a good idea.

As outlined the forces involved are so much greater that it is virtually impossible to do any meaningfull turning of ferrous material. Maybe small amounts of non ferrous of which is far softer and more readily machined. 

The wood lathe by comparison is not designed to handle anywhere near that amount of force applied to it. OK you can use a metal lathe to turn wood. It also is not advisable, because of the nature of the swarf or dust that comes off the wood.It gets trapped under the ways and slides and glues the whole works up, cos of the oil that protects the slides etc . As all the slides and ways machined to a fine tolerance and the second reason and most important is that nearly all wood has a measure of silica in it. This silica will rapidly wear away the cast iron bed, slides and ways in no time and totally screw up the lathe. 

A metal lathe is constructed to produce repeated turnings to close tolerances, pretty much the opposite of a wood lathe.It is not a precision machine tool, although in the hands of some they will produce fine work.

Its the silica that takes the edge off your HSS gouges etc when your wood turning. I have some blanks of Australian hardwood that will eat the edge off a Thompson gouge with a few passes as if it were carbon steel.

Take a good look at a metal turning lathe and see the difference do some reading and learn how to use one of these, or better yet go watch one in action. So you will understand the forces involved.


But if you're hell bent go for it, at best if you have any success it will slow and very rough, you will find it nearly impossibly to control diameters. square faces etc. Your greatest success maybe in the reduction of diameter by a few thou by using a file. If you use the correct file ie a long angle mill file.

Q


> uote:
> "Yeah I know, but asking very specific questions only gives you an answer that very often leaves you with more questions than answers.


...and a generalized question wont really do much better, you asked the question and didn't like the answer that's fine. But the answers were correct and warnings are very real as the dangers are.


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## james23

If you are interested in using wood lathe for turning the metal, is will be cheaper to you , but it would only be successful if you are using softer metals like pewter. These soft metals can be shaped at the higher speeds of a wood lathe. But you shuld be carefull as attempting to cut metal on a wood lathe because it simply runs too fast. You should use normal lathe to cut metal.


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## john lucas

The biggest reason not to turn steel on a wood lathe is it simply wasn't designed for it. You'll get lots of chatter because the bearings and tool rests weren't designed to handle those loads.
I have trued up a faceplate using the end of a sharpened file as a sort of scraper. You can't have any overhang because it can shatter but I took very light scraping passes and trued it up. Granted I only had to remove a few thousandths. 
I have roughed out shapes using slow speeds and a file. It's hard to do it accurately but it was good enough for what I needed. 
I would not try anything long on the wood lathe. A piece of steel like a rod can easily get out of control and can actually kill you when it bends and spends sideways.


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