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Sun God
12-07-2018, 08:46 AM
Haven't seen this mentioned here, but it seems like a great idea worth sharing. Nothing is ever new of course, and Lorch offered a similar freehand tool (however, without the radius and fence fixturing options this brings to the table that substantially increases its utility), as well as the F'Only lathe.


https://www.youtube.com/watch?v=Xs8XZ8X1I-g

Seems to me that the tracing fence would make a great ersatz taper attachment, and if one were inclined, they could replace the metal template used on the tracer with laser cut acrylic, or a 3D printed template, to work some really crazy profiles.

daveo
12-07-2018, 10:10 AM
Thats pretty neat!

Mcgyver
12-07-2018, 10:27 AM
that's kind of neat, I've not seen it with the tool floating on a platform like that. Free hand turning is very common in small work, i.e. almost all work done on a watchmakers lathe for example. Done with a rest and graver. It works well scaled up. I recently duplicated a Schaublin tailstock lever using free hand turning from steel - round end tool bit held with vise grips with a large boring bar as a rest. It worked well.

754
12-07-2018, 12:08 PM
Why is the drive so noisy ? Joint on the belt ? Maybe...

BCRider
12-07-2018, 12:41 PM
Now THAT is VERY COOL! ! ! !

I've done free hand turning on some aluminium but using a support bar off the tool post and a graver like tool similar to how clock makers do their work. It worked but at the larger scale was not all that great for good control. This floating tool post idea is way better.

And really there's lots of hand controlled ball turning jigs that are not much different than this tool in terms of controlling the pressure of the cut. The hand through a short lever controls the cut while the pressure of the metal being removed is transmitted down into the carriage.

If nothing else the platform with single peg and the finger jig off the holder would be lovely for simply ball turning. Less work to make than many of the ball turning jigs and more other uses as well. And with a bit of a tracer finger setup as suggested I could see making a lot of shaped profiles. The classic ball end handwheel being just one which is hard to do otherwise.

I suspect that Eccentric Engineering's (https://www.eccentricengineering.com.au/index.php?option=com_content&view=featured&Itemid=101) biggest problem is going to be that they are located in Australia and a lot of folks won't want to pay the shipping from there to them. Because when I look at the price of their basic table and cutter holder package (https://www.eccentricengineering.com.au/index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id=26&virtuemart_category_id=5&Itemid=110) at just $250A ($240Cdn, $180US) it's a pretty reasonable amount for the parts that are in the package vs the time to try to make such stuff. But I know it costs a bundle to ship anything over to them. And that would seem to be the case. Looking at their shipping rates it looks like it would add roughly another $70. I may be off but likely not by much.

reggie_obe
12-07-2018, 12:54 PM
Freehand turning: https://www.youtube.com/watch?v=IEsSS5KwZ9E

The Artful Bodger
12-07-2018, 01:33 PM
Excellent piece of kit!

BCRider
12-07-2018, 01:40 PM
Freehand turning: https://www.youtube.com/watch?v=IEsSS5KwZ9E

That's a few years old now. So clearly not a brand new idea. At least now I won't feel quite as guilty for "borrowing" the concept.... :D

To be fair the stuff that Eccentric makes is darn nice! And some highly interesting ideas.

Sun God
12-07-2018, 09:08 PM
Not a new idea at all, but I rather like the EE implementation of a pantograph tracer - it seems to me that you could even do some simple repetition turning tasks quite easily using such a tracer for example, and the idea certainly extrapolates to larger sizes.

I know I've certainly freehanded parts on the lathe before that I could have used this in stead, that probably would have gone a lot smoother. Things like big Nylatron rope guides and the like.

I mentioned in the OP the F'only lathe - for those unaware, here's a reference on it - certainly gives some interesting ideas:

http://www.lathes.co.uk/fonly/
http://www.2mm.org.uk/articles/fonly/fonlypt1b.htm
http://www.2mm.org.uk/articles/fonly/fonlypt2.htm

I agree on the shipping; our local post is horrendously expensive. He should probably get a US distributor.

754
12-07-2018, 09:34 PM
I got a question,
If I use it on my 7.5 hp lathe will it pull the tool in and take it for a ride if you cut too hard ?
I suspect on a lathe with fractional hp, that may not be an issue..

Sun God
12-07-2018, 10:07 PM
I think you could fit a hydraulic tracer on your 7.5HP lathe and not have to worry about such toys.

Galaxie
12-07-2018, 10:51 PM
I got a question,
If I use it on my 7.5 hp lathe will it pull the tool in and take it for a ride if you cut too hard ?
I suspect on a lathe with fractional hp, that may not be an issue..

I wondered about that too, but their site says: "A zero rake angle on the top of the cutter combined with a small front clearance angle ensure the tool bit and tool post block will not be pulled into the workpiece. So long as the tool bit is not extended out beyond the area of the base the Toolpost cannot be tipped over, no matter how much downward pressure is applied."

Not sure if that's true in practice, but I don't recall ever having had a zero rake tool pull in.

BCRider
12-08-2018, 01:35 AM
I got a question,
If I use it on my 7.5 hp lathe will it pull the tool in and take it for a ride if you cut too hard ?
I suspect on a lathe with fractional hp, that may not be an issue..

I "think" that if the cutting tool is kept with a flat top and if you use a limited side and nose rake angle to limit the maximum depth of cut that you should be OK.

I say this having done a few roundings of ends of rods I've made where I slip a round pin the size of the hole into my mill vise and then bring the arm up to the end mill and pull the arm around to round over the end of a handle or whatever concentric to the hole with the pin. It's amazingly controllable and actually quite easy even with a fairly heavy cut. Of course I do this so the metal turns into the end mill in the "conventional" direction. I'm not crazy enough to turn it into the cutter in the "climb milling" direction.

Sun God. Thanks so much for those links. I can see where an impromptu setup like that could do small model items in brass, aluminium, plastics and wood like a charm. And even small bits in steel.

PStechPaul
12-08-2018, 02:02 AM
That is pretty cool. It might be possible to add an upper support that sandwiches the free-moving tool holder between it and the bottom surface. The tool could be moved around with an extender arm to keep fingers away from the work and cutting edge.

vpt
12-08-2018, 09:22 AM
Very neat!

strokersix
12-08-2018, 09:28 AM
Watch out for turning brass this way! May need a negative rake angle to prevent grabbing the cutter. Same for acrylic.

Mcgyver
12-08-2018, 10:00 AM
I got a question,
If I use it on my 7.5 hp lathe will it pull the tool in and take it for a ride if you cut too hard ? .

For the most part tools don't get pulled in, it requires force to create the shear plane. There's exceptions to that of course, i.e. positive rake in brass, but the operator should know enough not machine like that, hand or machine held. What imo is needed for this is tool geometry that will limit DOC, so that even you put a lot of force in the X direction, you're still going to be able to hand the torque created by the resulting DOC.

I did the handle I mentioned a my 7.5 hp DSG. As it was a form tool (round end) there was zero rake, which limits DOC for a given force, i.e. how grabby the op is. That and the support (dull end of a 1.25" boring bar) was close to the work. For even less DOC you put on negative rake - think scraping, that what limits the DOC (i.e. put less rake on and DOC will increase to the point where it will be hard move the tool forward)

Maybe I was walking the high rope and didn't know it, but at no point did it feel risky. Although with that HP, if you were able to create enough pressure in the X direction the lathe has more than enough torque to take you and tool for a ride. Like a lot of things we do, you probably have to have your wits about you and be careful.

Here's what I turned, one's a Schaublin, the other my copy

https://i.imgur.com/xxRitIi.jpg

thaiguzzi
12-08-2018, 10:20 AM
Very neat!

Everything the guy (EE) does is very neat. Check out his T&CG design from a base bench grinder. And his Tangential tools.

quasi
12-08-2018, 10:21 PM
clock makers have been doing this for decades

elf
12-09-2018, 03:20 AM
clock makers have been doing this for decades

Centuries...

But the various jigs and tool holders are novel.

Beazld
12-09-2018, 07:25 AM
EE also has a sharpening system that looks interesting
This should be the correct video
https://m.youtube.com/watch?v=bzEQCvE1cIk&feature=youtu.be

vpt
12-09-2018, 09:20 AM
EE also has a sharpening system that looks interesting
https://m.youtube.com/watch?ebc=ANyPxKoxEr9Y9wrfDTrTwF46NoNiMblXyX6Kk81s BIjH9EsseudrAAXE7P0oOshwflGSxv7Q-FLjqKdxEZjKq45z66uvzLiwyg&v=__A2xtLF0AU

I think you have the wrong link to his sharpening system. I did watch some of his videos last night, the sharpening system he made up is great! I wish I had his patience.

Sun God
12-09-2018, 10:19 AM
Another good example of 'assisted' freehand turning; this setup on a Clisby lathe on lathes.co.uk:

http://www.lathes.co.uk/clisby/

A.K. Boomer
12-09-2018, 01:58 PM
wonder how it does on interrupted cuts lol

looks good for making small trinkets out of soft material that are just to look at for their shape but probably not to be confused with anything "precision"

BCRider
12-09-2018, 03:25 PM
wonder how it does on interrupted cuts lol

looks good for making small trinkets out of soft material that are just to look at for their shape but probably not to be confused with anything "precision"

Certainly not for precision work. I think that was a given. But I can see it as a nice option for shaping things like tear drop handles to go with ball end handles on machines. And with a "center pin" and yoke that rides that pin for turning ball ends too. At least well enough that just some final polishing is all that is needed. And for me just this sort of work would support the idea of buying or making such a setup.

elf
12-12-2018, 02:40 AM
wonder how it does on interrupted cuts lol

looks good for making small trinkets out of soft material that are just to look at for their shape but probably not to be confused with anything "precision"

You need to step back and look at some of the work done by hand in the 16th through 19th century.