Router Lathe - a different way to skin a cat

[Olaf Vogel]

I don't know that I'm too concerned about tailstock support if you keep speed well down eg 20rpm. Anything faster may dislodge the router, and you really don't want that flying across the shop.

IMHO it's the feed rate at the router bit that is critical. Which means that the rotation should be slowed as the diameter being cut gets bigger.

Brian, you've got it! low speed.

For whatever reason, I really like working with large pieces. While its difficult, I do enjoy the engineering challenge and those large bowls when finished really have the wow factor.
That being said, I thought for a long time about how to do this, with green wood. Obviously the pieces start off unbalanced. They're too big for a band saw. I've seen people do some amazing carving with chainsaws, but I don't know how (yet?!?!)
So now run this up to cutting speed, maybe 300 rpm. The forces would be unreal. No matter how big or heavy your lathe is.

This is lathe is picked up for $400 and spent about 2 weeks stripping and cleaning. 2 years ago I realized how much of this really great old machinery is still around. Most doesn't meet modern technical standards for accuracy, safety (belt drive), functionality etc. But its professional grade, well built and can be serviced without fancy electronics.

This is an 1926 American Tools Works, 16", with 10" riser blocks, for 36" swing (But i think its only about 32" over the carriage).
Even at 4000 lbs, and being bolted firmly into concrete, the idea of a 300 lbs piece, off balance, rotating at 300 rpms scares me.
I've tried it on my my pattern lathe! Took me 2 days to get the blank balanced enough to spin and another 2 to get it into the right shape.

So this lathe runs from about 10 rpms (using the back gears) up to about 500 rpm (which I've not yet hit)
Very low rpm, hence no need for a tailstock. The bolts are 1/2" x 6" grade 8. the spindle is 2.75" dia.

The router sits on the carriage on a DIY contraption of oak (I don't have fancy metal working tools and have changed the design a few times already). Maybe I'll have a metal one made if I finalize a design, but that might be a ways off.
Yes the router is attached by zip ties and so far thats a good thing. i.e. if I over-drive the cutting speed of the router, the zip ties break and it falls off. It has happened twice and its not dramatic.
The next gen solution will be to allow the router to tip down and out of way if the feed speed it too high. That involves a new design....sigh.

Yes, I'll rough trim this up a lot with an electric chain saw. The circle I cut in the end (took about 60 sec) is so I know exactly where center is and where to cut to with the chainsaw.

So far, this is an experiment and there's a pretty steep learning curve. I'm hoping, that as I learn, I'll be able to do things wildly off-center, multi-axis etc.
Since its a metal lathe, there's fine controls on the x/y axis, curves of various diameters etc. It even has automated feed speeds.
I will be limited on what I can do on the inside of hollow forms. however I'm hoping that at that point the blank will be balanced and I can put the piece on my other lathe for hollowing.

I do miss the traditional method of holding chisels, getting into that zen state and working on a piece.
My regular lathe is currently disassembled, at the cottage and waiting for a new shop to be built.... now if it would stop friggen snowing there.

All that being said, I'm pretty good at 3D visualization, but some of this stuff is giving me headaches! Its serious fun though experimenting.
And if work would stop getting in the way of my play...I'd be back out there.


Olaf

[Brian Finney]

Olaf,

Rather than a chainsaw consider an Arbotech Pro 4 woodcarver http://www.arbortech.com.au/view/woo...o4-woodcarver/, or similar; basically an aggressive woodcarving disk on an angle grinder.

Another useful toy would be arbotech's mini grinder fitted with a saburr 2" carbide donut http://www.chainsawsculptors.com/saburr/Index.htm. I used both on my bowl - the shape of the bowl follows the shape of the bark and is triangular. Your's is almost round but that exisiting 'lip' on the top edge of the bowl could be a feature esp if you cut the top edge opposite lower - this is where the carbide donut would come it - both to cut the top edge lower and reduce the wall thickness in places that are outside the router circular cut.

Keep the pics coming

Brian

[Olaf Vogel]

While trying build a website, I was looking around for old pics. I realized that I never followed up on this.

I did finally get the router lathe working - to a point. That large block didn't work out, so I chopped it in half and kept going.
I was able to get it carved round and weight down to the point where I can turn it on my regular lathe.
https://plus.google.com/photos/10223...97319200866097

So some success.

Initially I used a flat sided router bit, because it was cheap. I found that 1/2" spiral bits a just as cheap and much more aggressive.
But I would like a solution that removes wood faster than a router.

In mean time, I finished building my shop and have been pre-occupied by new toys there on weekends.
That gives me weekdays to play with this one. But this winter has been brutal in Toronto. Consistently -20C and windy as hell.
There's no incentive to go outside; my wife has opted for hibernation.

<awaiting spring - ok, I'm a wimp>
Olaf

[Don Bunce]

Instead of using a router, I would suggest a boring bar along the lines of what this guy uses.

http://www.poetv.com/video.php?vid=109020

[Olaf Vogel]

I actually did see that and considered such a solution. Not the easiest thing to build or mount on a lathe.
He's using a large end mill (~ 2") on a shaft, not sure how to mount a collet, a few pillow blocks and a motor. But it would need about 5k rpm.

Then some sort of mount that allows controlled movement.

I cheated and used a $70 triton router with speed adjust instead. Figured I can trash the router if this all fails - I hate it anyway.

[Don Bunce]

It shouldn't be too difficult to make something to attach to the cross slide. You'll have to turn the carriage and cross slide wheels like an Etch-a-Sketch to cut curves, but if it is mainly for roughing out, that won't be a problem.

As was mentioned earlier, a chainsaw wheel on an angle grinder is a good idea, too.

Here is another video that might provide some inspiration:

http://www.mnoriginal.org/episode/mn...2/virgil-leih/

[Olaf Vogel]

This is the third time I've watched that video.

Both these guys are obsessive, way out there and nuts.
However, its my kind of nuts. And I greatly appreciate what they'd done.
Given their huge investment of time and money, I hope they are enjoying at least enough success to keep going.

Unlike Virgil, I don't think I'm nuts enough the use a chainsaw on a running lathe - that scares the %^&*( out of me.
I would love to have his Oliver 66. and if I found one for sale, I might mortgage the house for it.

But an angle grinder and an arbortech industrial wood carver would be good. I just been able to pull the trigger on a $200 blade.
Heck, that half of what I paid for the lathe!

Do I love working with large pieces. Similar to the comments in both video, I find incredible beauty in the natural grain and patterns. Large works do just display that better

Olaf

[Don Bunce]

Olaf,

I ran across this video on Youtube, thought it might be something to consider...

https://www.youtube.com/watch?v=hqWBnMp3aNY