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redmond
20th May 2004, 07:27 PM
hi i need to do some accurate turning with wood. more accurate than i could ever do by hand. now what im looking for is a way to get a tool post like a metal lathe on a wood lathe. does anyone know of a lathe that is designed like this, or an attachment tool post for a wood lathe. i dont need to chase threads or do anything that might require the auto move thing that maetal lathes have i just need to hold tools to make very accurate straight edges and the like.

thanks alot
tom

ozwinner
20th May 2004, 07:32 PM
You can get a copier, then all you need to do is fit a straight edge to the copier for the tool to follow.
Timbecon sell them.

Al :)

redmond
20th May 2004, 07:35 PM
thanks thats a good idea but would a copier be able to hlollow a straight line as well?

fingers crossed
tom

ozwinner
20th May 2004, 07:37 PM
A copier will cut any shape you want, all you do is make the template to your design, and the tool follows it.

They cost $100- $200..

Al

redmond
20th May 2004, 07:39 PM
yes but im trying to make a drum shell and the copier would work great for the outside surface but i also need to hollow out the inside would a copier be able to do this

sorry for my ignorance
tom

RETIRED
20th May 2004, 07:41 PM
How big is it?

ozwinner
20th May 2004, 07:43 PM
Dahdaaaaa

http://www.timbecon.com.au/productsdetail.asp?sectid=12549&parentid=12479&prodid=27673
Al

redmond
20th May 2004, 07:46 PM
they would vary but mainly between 8 and 14 inches in diameter

thanks al that might work if i could fit a hollowing tool to it

cheers
tom

RETIRED
20th May 2004, 08:01 PM
You thought about how you are going to hold a hollow form 14" in diameter?

redmond
20th May 2004, 08:04 PM
i was thinking a big chuck with jaws that expand outwards.
am i being naive?

thanks
tom

ozwinner
20th May 2004, 08:09 PM
Could you make it like a Didge', form the outside, then let the white ants eat the inside?


Al :confused:

RETIRED
20th May 2004, 08:12 PM
The chuck you would need would be gigantic and very heavy.

As a thought you don't know an engineer with a big lathe do you?

RETIRED
20th May 2004, 08:16 PM
Good to see you back Al.

redmond
20th May 2004, 08:19 PM
hmm cant say i know any qualified engineers but i am a student mabe the department will have one.

thanks guys at least it give me somthing to think about.

cheers
tom

ptc
21st May 2004, 10:42 AM
This will put the cat among the pidgeons
buy a symtec.

arose62
21st May 2004, 12:36 PM
Now, I'm totally ignorant about the engineering of drums, but I'm assuming that you're making the boom-tish musical/noisy type (not the 44 gallon type).

My approach would be to get a sheet of some flexible wood, and wrap it around a form, then work out some way of joining the edge.

If it needs to be a thick skin, you could make it from a few layers, and stagger the joints for strength.

Cheers,
Andrew

silentC
21st May 2004, 12:58 PM
Drum shells are usually made by laminating several sheets around a circular form. I don't think a lathe is usually involved in the process, unless they use one to true it up after assembly.

Someone on here posted once about how they had made a wheeled platform for their cross slide vice which they attached to the ways. He could clamp a tool in the vice and use it a bit like a metal lathe. I had a quick search but couldn't find it. It's here somewhere (or did I dream it :rolleyes: )

redmond
21st May 2004, 06:07 PM
symtec? it sounds like the plastic explosive the SAS use? :eek:

thanks silentc i was just down at carbatec and that was one of the things that they suggested

cheers
tom

jhunt_2000
22nd May 2004, 10:07 PM
Er, isnt that Semtex???

redmond
22nd May 2004, 10:16 PM
thats the one
give us a break its sounds close :o

cya tom

bobz
23rd May 2004, 03:43 PM
Well yes, you can make drums on the lathe. Here`s a photo of a piccalo snare drum I made a couple of years ago. The shell is made up from staves planed to the appropriate angle on the jointer. I turned this one by hand, but as I want to make some more deeper ones, I have been toying around in my mind a machanical way of doing this. I`m busy on another project at the moment but I will come back to this when it`s finished. Another important thing when making this drum is having a lathe with variable speed. When I made this drum I only had fixed speeds on the lathe in the photo, but I have now uprated ths machine to variable speed. I felt that the bottom speed of my lathe at the time, (450 revs) was a little too fast for this diameter of work. I also had to spin the work on the lathe by hand just before I switched the lathe on because the sudden start on this diameter of work makes the belt slip on the pulleys.

Barry_White
23rd May 2004, 05:31 PM
Hi Redmond

I was interested in your dilemma in turning your drums out of timber.

Why not build them up out of segments. You could build the on a base and fix it to your base plate for turning. When you have tured it up you could then just cut the base off and then you would have your drum carcase. To show you what I mean go to the thread below and have a look at the principle of what I mean and turning 14 inch diameter is not a problem.

BTW if you wanted them to be fairly deep you could make two or three of them and glue them together.

http://www.woodworkforums.ubeaut.com.au/showthread.php?p=57790#post57790

redmond
23rd May 2004, 06:12 PM
that looks good bob how does it sound compared to ply drums?

barry i am really looking to make the drum out of a single pice of wood as i have the trees that could be put to this purpose and i have heard that drums made this way sound amazing. what im really after is a way to accuratly trun straight lines. a metal late would be nice excpt they cost a fourtune so what im looking for is a way to adapt a wood lathe to hold a tool post.

thanks
tom

echnidna
24th May 2004, 07:16 PM
Redmond,
What are the approx dimensions of the drum\s

redmond
24th May 2004, 08:31 PM
well to start with about 14" diameter snare but id realy like to be able to turn kick drum swhich are 20" to 24" diameter. now i know this is big but it must be possible, and im starting to think im gona have to get a custom built lathe that has no bed made up by an engineering company :(

cya
tom

Bunyip
24th May 2004, 09:00 PM
well to start with about 14" diameter snare but id realy like to be able to turn kick drum swhich are 20" to 24" diameter.

Tom,

I'm not a turner myself, but I can imagine the forces associated with a two foot drum sized hunk of tree spinning around. You are talking some serious industrial size behemoth of a lathe here.

Not wanting to discourage that entrepreneurial spirit of yours, take a good look at the market you would be competing in ... Would it pay??

If you have some trees on that place of yours that you are itching to fell, why not just get them milled and value add that way. Buy a second hand mill and mill your neighbours as well :) . There is a ready market for some of the WA timbers here in the east coast!

redmond
24th May 2004, 09:22 PM
well ill get a custom athe costed and see if i can afford the start up cost. im still looking for a second hand mill to saw up the bulk of the trees but drums could be a little niche market.

thanks
tom

rodm
24th May 2004, 11:08 PM
Tom
I made a faceplate lathe twenty plus years ago that theoretically would turn over a six foot diameter piece of timber. The largest piece I turned was about 30 inches and six inches thick. The lathe was made out of 8 by 3 channel and the spindle was two inches and mounted on pillar blocks. The faceplate itself was 12 inches and through a triple reduction pulley system it ran at about 50 rpm on the slowest speed. It was real heavy duty and weighed a ton - figuratively speaking. I bolted it to the concrete floor of my shed with eight loxons spread over a fair length of 3 inch angle iron. Fairly easy to make as you don’t have too much to line up like a tailstock but things like tool rests have to be fairly long or floor mounted.
It took a while to find a large enough piece of timber to test this beast so I had plenty of practice on about 12 inch diameter bowls and platters. Eventually the perfect blank turned up - a piece of Jarrah burl (we called it niggerhead then) about 30 inches in diameter and six inches thick and well seasoned.
Lesson 1
Mounting the piece was difficult as it was hard to support the weight of the timber, faceplate and square it to the shaft to start the thread. If you are thinking about turning heavy timber then get some help to mount your job or install a chain block over your lathe.
Lesson 2
Turned on the lathe and the experience is best described as fantastically frightening. The concrete slab that the lathe was mounted on and which I was standing on started to move up and down with the out of balance timber. Although the movement felt more severe than it actually was it did worry me that the lathe would break free and cause some damage. If you are contemplating making a lathe this size then make sure you have an adequate depth of footings preferably with lathe mounting bolts set in the concrete.
Lesson 3
A hefty piece of timber attached to a rotating shaft becomes a very effective flywheel and doesn’t stop easily. A standard set of woodturning chisels are just not long enough to give the operator enough leverage to control the cut. I won’t embarrass myself any further here other than to say get long strong chisels and until the blank is perfectly round go real steady. There wasn’t the choice of chisels available then so I took up blacksmithing in pursuit of the perfect chisel so be careful where your hobby leads you.

The experience was fantastic and it gave me an opportunity to do something a bit different to the other turners. The lathe along with all my blacksmithing gear was sold years ago to a person that was into vintage wagons and cars. He wanted the lathe to true up the outer rim of the wooden wheels. My neighbors were objecting loudly to the percussions in tune with CCR so the decision to stop blacksmithing was really forced on me. I would hate to think what a 350lb anvil and a large swage block would be worth today.
Thanks for giving me the chance to revisit this experience and I hope I have been able to pass on some tips for you to consider. By the way I have just recently returned to woodturning after promising that I would never do that filthy hobby again. I now have a Delta Midi that will turn a massive 8 inch bowl so perhaps the itch never leaves you after all.

ozwinner
25th May 2004, 02:38 PM
Guys think out side the square.

Make a capstan lathe, then the log is sitting up in the air, less sideway force on the chuck as all the weight in going down.
It would be easier to make than a conventional lathe.


Al

redmond
25th May 2004, 03:52 PM
sorry al your going to have to elaborate. whats a capstan lathe :confused:


tom

ozwinner
25th May 2004, 04:22 PM
Hi
A capstan lathe is a lathe where the work piece is held in a chuck at 90 degrees to the floor.
So rather than trying to defete gravity, as with a conventional lathe you get it to assist you.
You could make it very solid as it only need to be 300-400mm high.
Its basicly a very solid turn table.
It doesnt have to turn very fast, just fast enough to take a shaveing off.

Ok, I think Ive got the name wrong, but Im sure you get the picture.

Al :)

Al B
25th May 2004, 06:27 PM
We used to use a machine to plastic wrap rolls of paper, 1700mm Dia X 1300mm High Each paper roll Weighing close to 2000Kgs, I'm not suggesting that you use a plastic wrap machine but I guess with a few modifications It could be made to turn a log. Just a thought :confused:

Al B :)

Bunyip
25th May 2004, 07:33 PM
Guys think out side the square.

Make a capstan lathe, then the log is sitting up in the air, less sideway force on the chuck as all the weight in going down.
It would be easier to make than a conventional lathe.


Al

Then again, why use a lathe at all. The task could be accomplished easily and more safely with a variation of a horizontal milling machine.

The outside surface could be trued and sized this way, the inside portion would need to be bored out (can you get a 2 foot forstner bit? :rolleyes: ). Or, once the outside is trued and sized, it would be much safer and easier wack onto a rodm or ozwinner lathe and turn out the inner part.

rodm
25th May 2004, 09:01 PM
Al,
The Capstan Lathe is a novel idea but using the chisels would be a bit difficult. For the outer surface the rest would be vertical and you would have to move your body up and down which may not be comfortable or safe. There are some situations when moving the body up and down is quite satisfying but perhaps not here. :confused: The leverage would also be sideways and you would not be able to use your body weight like you do with a connventional lathe setup. Inside turning would have to be from the oposite side and deep turning might see the operator tumble dried. Now if you are into that sort of rough and tough then go for it but these days I prefer not to do turning tricks. Hmmmmm Tricks as in stunts :D

Bunyip,
Even on a mill setup you need a rotary table to mount your work for cylinders. The mill idea has merit because the job is stationery and the cutter moves.

Redmond,
Before I built my lathe I thought about modifying a cement mixer. I can't remeber why I gave up on that idea but it might trigger somthing for you. Ozwinner now all you have to do is ditch the bowl and strap on a bit of timber at smoko. :D

ozwinner
26th May 2004, 05:05 PM
Ozwinner now all you have to do is ditch the bowl and strap on a bit of timber at smoko. :D
You sound like my missus, a strap on, please.

Al :D

RETIRED
26th May 2004, 06:48 PM
Gooday all.

Al you are right, you had the name wrong. :)

A turret lathe is what you were thinking of. Big brutes of things that require a great deal of setting up.

Jigsaw
26th May 2004, 08:28 PM
Thinking outside of the square or was that round.
I haven't tried this idea but was planning something similar in the near future. Why not use a router mounted in a drill press (or similar concept) and rotate the wood by hand in line with the speed required by the router. Obviously if you have to remove the amount of wood in a 14" circle it will take a while depending on the power of the router and the bit shape / size.

Before you guys savage me with such an idea, keep in mind I only bought my first lathe a week ago. I have a couple of 1/2" routers but I purchased a 1/4" GMC router (so that the motor assembly can be removed from the base) to use in a jig arrangement as per an article in the Australian Woodworker issue 114 page 68.

I eagerly await your feedback.

ozwinner
26th May 2004, 08:33 PM
Before you guys savage me with such an idea,
Savage you, what are we Pit Bulls? :p

Woof. :D

Al

redmond
26th May 2004, 09:32 PM
well the custom lathe idea got shot down. 10-15 grand to get a one off built. i think i could build a lathe my self but i dont think i could get the straight line accuracy needed for the drums.

so ive had a look around at second hand metal lathes, one of the engineers sugested buying a smaller metal lathe second hand and puting a riser block under the head stock and an offset riser for the tool post.

well i found this old turret lathe for 4 grand which is looking good at the moment as it has a 23 inch swing over the bed and about 17 inches over the crossslide its an old turret lathe what are the pros and cons of this type of lathe.

thanks
tom

gatiep
26th May 2004, 10:01 PM
Some of those lathes ( That era of design in your picture ) had bushess rather than roller bearings. They could be worn.

I think that the price you were quoted is outrageous. What you need is a simple headstock with a spindle, geared down very low with a powerful motor. The assembly to make straight line cuts is relatively simple

HOWEVER

The main problem is the size of what you want to turn.This presents problems re mounting and tooling. It has been overcome by many people....at the Perth for Wood show last year there was an urn, about 1,6 m high by about 600 or more mm diameter that was turned from red gum I think. Some guys have made lathes from car rear axles and drive them through gearboxes with anything from a 4 cyl to V8 engines and use vehicle springs as turning tools.
They did not cost 15 grand. It took a lot of inginuity from these guys, but they did it.

Problems that I forsee is the instability of the timber once its been turned. Surely you have to turn to a relatively thin wall, otherwise a crane will be required to move the drum. Turning an object of that size to a wall thickness of 6 or 10 mm is definately not something that I would class in the " ahhh thats easy box".

Personally I think building the lathe to be able to do that will be a minor problem. Actually doing it and repeating it successfully will be a problem. There is a lot more to it than cutting down a tree, hollowing it out, turning it to a cylinder and you're done. There will be factors like moisture content, splitting, warping or deforming, the object disintegrating while being turned etc etc to contend with.

Good luck


Joe

Bunyip
27th May 2004, 11:25 AM
Personally I think building the lathe to be able to do that will be a minor problem. Actually doing it and repeating it successfully will be a problem. There is a lot more to it than cutting down a tree, hollowing it out, turning it to a cylinder and you're done. There will be factors like moisture content, splitting, warping or deforming, the object disintegrating while being turned etc etc to contend with.
Joe

Tom,

As I alluded to in a previous reply - before spending a cent do you homework, do your homework, do your homework (that part is free).

I think I read that you were attending uni. Not sure what course you are doing, so my comments may be equivalent to telling you how to suck eggs :o If not, you have access to business management and development specialists - use them.


Assuming you overcome all of the technical difficulties - you then have a product.

Why is the product of value - what value are you offering the customer?
Who is your market, what is the size of the market, what is the depth of the market?
Is it a developing market, a mature market or a declining market?
How does your product differ from others in the market - what differentiates it? (refer to first point)
How are you going to promote your product?
How are you going to distribute your product?
How are you going to compete with existing brands?
Who are your competitors (and if there aren't any, if you are successful there soon will be!)
And above all, after taking the above into account, are you able to make a profit from your product (given you may have technical difficulties)?

I don't want to put you off by any means - but I don't like to see anyone waste money through lack of planning :)

Bunyip

echnidna
27th May 2004, 09:41 PM
I dont see any great need to use a lathe to make drums of that size.
If you hollowed the log with a chainsaw you only need to true up the inside which could be done by rotatiing a router or grinder with arbortech blade around the central axis of the log. Making a jig to hold a router or grinder in the centre axis shouldnt be that hard.

Bunyip
27th May 2004, 10:13 PM
If you hollowed the log with a chainsaw ...

Sorry echnidna, I have to put my safety hat on :)

To hollow out a log with a chainsaw would involve using the 'forbidden' bar tip. What you are asking for here is major kick-back of the saw, the result being a whole heap of nasty little teeth heading for your face. Not a pretty thought.

Better get back to work ... :(

Jeff
1st June 2004, 05:14 AM
I've done a bit of turning of the nature you're describing, but not at as large of a diameter. Here's what I've learned:

1. You will need to turn the workpiece slower than you think.
2. You will need to find a very good way of attaching the workpiece to the
lathe. Remember you're talking about using the end grain, and that can
be a bit challenging.
3. The wood will not remain true for very long, no matter what you do. Even
if it's totally dry when you start, removing the center of a log will always
result in changes in stresses. If you are trying to save the outer, or
sapwood, you'll have even more trouble. The odds are very high that the
wood will crack, but only after you've done all the work.
4. It CAN be done, and it looks awesome when it works.
5. When I put such a piece of wood on the lathe, before I ever turn the
lathe on I true up the workpiece as much as possible with a power plane.
The heavy side will always roll to the bottom, so it's easy to know where
to take more off. Remember, it's more important to initially true up the
workpiece by weight than by actual roundness. When you first turn the
lathe on you want things as close to balanced as possible.
6. NEVER STAND IN THE LINE OF FIRE!!! Turn the lathe on for a few
seconds at first and turn right back off. Increase your "on" time only
after you've run the lathe and assured that the piece is secure. Yank on
the workpiece with the lathe turned off every so often to make sure it's
staying tight.
7. First clean up the outside of your work, it's much safer to have a smooth
surface to work around.
8. As you hollow out your workpiece, the balance will change. I've found
that a "sweet spot" speed that can be found by adjusting the speed up
or down a little as the balance changes, where the lathe will have the
least vibration. A variable speed machine is highly reccomended.
9. When you start to get tired or frustrated or for any other reason are not
able to totally focus on the work, turn off the machine and walk away.
10. Try out your ideas on smaller pieces first, and you'll find out all these
things and more. A 300 lb. piece of wood moving at 60+ mph is a serious
piece of wood, and you'll want to know how to react if it comes loose...
11. Turning the end-grain is risky business!

There are reasons why most turners don't do this kind of stuff, but I say if you think you're up to it, great. Just don't do it as a novice.....

sailingamerican
2nd June 2004, 01:08 PM
Yes there are attachments like metal lathes made for wood lathes and yes you can find old metal lathe parts and make your own. I have had one for 35 years on a wood lathe that I bought form one of the vice presidents of Ford moter company in Detroit. I have 5 lathes. Now for the bad news they will not have enough travel to go all the way in. It is not worth the effort. You are going to need to use a face plate and turn the outside and it is not that hard to make a streight inside cut on the inside face. What will be hard is that you will need to make a jig to hold the drum when you take it off the face plate.
1. Make the drum longer on both ends.
2. Turn a step down piece that will fit into the drum that you have turned.
3. Scred the drum through the sides into the steped piece and screw it to
the face plate.
4. Turn the other end and hollow out to match the other end
5. Cut both ends to length and you will have your drum.
6. Now the hard part finding the dead center on all pieces. It can be done
Good luck Richard