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SawDustSniffer
18th November 2006, 05:47 PM
i was looking at repacing my China made tin foil clad sad excuse for peace of machinery (my Lath) and at the prices of good wood laths i can bye a 2nd hand industral metal lath ,
1) is any one useing a metal lath for wood work
2)can you get wood laths with 50mmdia holes through the chuck

the lath i was looking at today had 3 phase motor , 600mm dia chuck
the bed is 8 foot long , has all the thread cutting gear ,the max speed of 10,000 rpm seems enough

all the tail stock and cutter head ( i would make a rest for ) are mounted on windable threads with lock handes , easer than bolt down slide set ups

would pay 2x as much as a wood lath if you could cut metal in it as well

go's under Auction tuesday

why cant you use a metal lath for wood

Skew ChiDAMN!!
18th November 2006, 07:43 PM
You can use a metal lathe for wood BUT...

a metal lathe doesn't normally have a tool-rest as needed for woodturning. I believe that morse tapers aren't that common on metal lathes. I could be wrong, though... wouldn't be the first time a metal lathe tends to involve the use of oil. Oil and sawdust is not conducive to a happy relationship. you'd still need to buy a self-centering chuck suitable for woodturning. Unless you're tooled up to make your own jaws? Hint: it takes more than just a metal lathe. ;)

Slow6
18th November 2006, 07:48 PM
I cant think of any reason why you cant do it.. personaly I wouldn't do it simply because I wouldn't want sawdust anywhere near my metal lathe, tbh I'd want em in seperate rooms. I have seen my grandfather turn simple wooden disks on his metal lathe for stands for his steam powered contraptions but we're not talking anything flash.
another thing I'd think about is if you can fit a woodturning chuck on it (you DONT want to bother with a metal working chuck for wood) and how good is the personal access, its hard enough leaning over the bed to do face plate work if you dont have outboard capacity and I imagine a mtal lathe would be even chunkier bed-wize.

it's certainly do-able but I'd be weighing up all the work and mods you'd have to do to it and keep an eye on ebay and the trading post in the meantime. I've seen some very reasonable deals recently, no need to spend vicmark prices to get a good woodlathe capable of anything you want to throw at it.

edit: or just take Skews advice:rolleyes: while ol 2 finger typer here plods along:o

hcbph
18th November 2006, 11:56 PM
I have both a metal and a woodworking lathe. At least in my case I don't see dong woodworking on the metal lathe. The metal lathe's range of speed is very slow, suitable for metal but not wood. The metal lathe's tool holder carrier is very large in relation to the machine so it cuts down the diameter of turning you can make. The length of the bed is less than 1/2 of the length of the woodworking lathe I have. On top of that, the metal lathe cost me more used that the wood lathe did new.

If you had a way to offset those shortcomings, it probably would work but not with the one I have. The biggest liability though is the speed of the machine and bearings. It has to run a lot faster than designed (in most cases) to do wood vs metal.

Paul

SawDustSniffer
19th November 2006, 03:59 PM
Atool rest would be easy enough to make ,mounted on the cutter post
The tail stop has a 50mm chuck in place ,and i didnt go through the crate of bits that comes with it .
Good point about OIL and SAWDUST / tannons , will have to ask if waxing the steel might be better
For a self centering chuck i thought of using my chuck now fitted into the lath's chuck with a peace of threaded waterpipe
Personal acsess might be a problem , could put a padded seat on the bed and ride it like a horse??/ lol

this thing is huge , 3 foot Dia swing , 8foot bed ( between chuck and tail stop ) for turning pens it might be a bit of over kill , but logs for 4poster beds

will bid up to $7000 on it , ( it has no reserve tag on it )

then ill have to hire a truck and big forklift to move it ?

shed aready has 3 phase in it

Slow6
19th November 2006, 04:32 PM
sound like fun if nothing else Sniffer:D

be sure to take plenty of photos along the way and let us know how it goes.

DJ’s Timber
19th November 2006, 04:48 PM
A lot of the engineers I know won't let timber within cooeee of their lathes, as timber is finer and has lost of fine dust which can get into all the screws regardless of how good your seals are causing them to bind up. Because metal normally comes off in swarf and the filings are coarse they don't normally interfer with the screws.

SawDustSniffer
21st November 2006, 11:05 PM
turned up today , eager to blow $7000 , and came across the Owner of the Cockatoo farm i care take for , after breaf greatings ,He told me he would be bidding on the same lath ,for one of his numerus companys in darwin and that i should heep my hands down , :mad: , If he didnt give me free rent , free power , free water , i would have told him to get stuffed but no good ####ting in your own nest :mad: , i hate rich people , He got it for $9250 so i would have missed out any way

Slow6
21st November 2006, 11:23 PM
do I smell roast Cockatoo for tea tonight?

hughie
22nd November 2006, 12:57 AM
Wood versus metal.

There are some differences that make either one not very suitable to swap usage.

Basically, the way a metal lathe is used with all its slides, cross slides and saddle is very cumbersome compared to a wood lathe which is largely used freehand. Its cumbersome and heavy due to the material being worked. Not to mention the chuck which has the propensity to crush timber with the three small points of contact on the jaws [ 4 on a 4 jaw but this chuck is not self centring].

Most metal lathes have some form of lubrication to the slides, which is not helpful when you have wood dust around. The reason that machinists dont like wood dust is the silica content of some timbers. Which will wear the 'ways' and dovetail slides prematurely. This sort of wear is fatal to a metal lathe and is very expensive to repair and in severe cases not repairable. :mad: bummer!
Speed is another factor generally as they are much slower. It is possible on most lathes to change drive pulleys to increase the speed, as good lathes are belt driven. If not they will actually reproduce the gearing teeth pattern on the work being machined. :( bummer!

The next problem is the speed capacity of the chuck now that we have sped it up. The max rpm of a chuck is generally governed to the original makers specs. High speed chucks are available at a much higher cost.
The last you want is a 5-10kg chuck coming apart at high rpms, frightening does not begin to explain the experience. :eek: :eek: :eek: :eek: :eek: perhaps death wish is a better term here. :D

It can be done but why would you, as it will never be as good as a wood lathe and in the end it will not last along as it should. A well looked after metal lathe can last a life time.

tashammer
22nd November 2006, 01:43 AM
i was envisioning full radiation gear suit plus the lathe being enclosed and worked via those rubber claw arms. Maybe also wear anti-blast gear as well (in case the bits of chuck decides to go their separate ways).

Interesting how increased levels of safety awareness and self-protection have been growing - bodgers wouldn't even be able to do their work for both OH&S and environmental reasons.

Maybe there is a need for some sort of tradeoff between health and safety as the more we are protected then the less healthy we are. Think of kids in cities who are more prone to diseases because they haven't been allowed to play in the dirt - there is a wad of this sort of research now.

Use it or lose it.