Benchtop Lathe + CNC Mill = ???

Hello,
I am a hobbyist machinist and I wanted to get some advice or comments on the following idea/project:

I have a Grizzly G0765, 7x14 benchtop lathe, a toy really, that I can lift with one hand.
I also have a really nice Index Wells CNC 3000lb mill that works great under mach3 (2000oz steppers instead of servos).

Idea: bolt the lathe to the mill table, and use mill's X and Z axes to perform CNC operations on the lathe. I would need to make some toolholder that would hold a lathe tool in the spindle, and use mill's spindle brake to hold it steady.

I am also planing to upgrade lathe's bearings to taper bearings, something a lot of people with these lathes do.

So, I am curious if there are any unexpected problems that I would run into?
I am expecting that due mill's rigidity, I should get excellent surface finish and accuracy despite using this toy lathe. Am I right to expect this?

Thanks for any comments or suggestions,

Alex

I fail to understand your reasoning. An indexing fixture bolted to the table will do the same thing a lot easier and be 10x more rigid and versatile than a piece of Chinese crap toy lathe.

Just put your stock in the mill spindle and your turning tools on the table.

Dualkit said:

I fail to understand your reasoning. An indexing fixture bolted to the table will do the same thing a lot easier and be 10x more rigid and versatile than a piece of Chinese crap toy lathe.

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Think you can spin an indexer fast enough to turn with?

mhajicek said:

Just put your stock in the mill spindle and your turning tools on the table.

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This! Depending on length/diameter.

couch said:

Think you can spin an indexer fast enough to turn with?

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No. Why does he need to turn with a mill when he has a lathe? I am confused here.

It is clear to me with these postings, that these new OP's are NOT
reading the guidelines as to what is and is NOT allowed here.

Can you blame them ? Look at each sub forum, and I see minimum
4 "stickies" up top. Given the attention span of todays posting
public.

The moderators need to clean these out, and Make ONE sticky, and make it clear
as to what is and is NOT allowed.

aparfeno said:

Hello,
I am a hobbyist machinist and I wanted to get some advice or comments on the following idea/project:

I have a Grizzly G0765, 7x14 benchtop lathe, a toy really, that I can lift with one hand.
I also have a really nice Index Wells CNC 3000lb mill that works great under mach3 (2000oz steppers instead of servos).

Idea: bolt the lathe to the mill table, and use mill's X and Z axes to perform CNC operations on the lathe. I would need to make some toolholder that would hold a lathe tool in the spindle, and use mill's spindle brake to hold it steady.

I am also planing to upgrade lathe's bearings to taper bearings, something a lot of people with these lathes do.

So, I am curious if there are any unexpected problems that I would run into?
I am expecting that due mill's rigidity, I should get excellent surface finish and accuracy despite using this toy lathe. Am I right to expect this?

Thanks for any comments or suggestions,

Alex

Click to expand...

Tormach did that in 2008 to 2010 -ish if memory serves me right.


They called it the "DUALITY LATHE"... and I think there was the future possibility of running a indexer/ rotary table (gizmo) on the "back side " of the spindle...

I believe Greg Jackson (Founder of Tormach) (sadly no longer alive) actually got a patent for the Duality lathe... The patent examiner didn't cite any prior art ( I believe.).

Not sure if that's of any help

The duality lathe may have been cancelled later on but I believe they sell a different type of bolt on spindle ? NOT really in the loop on that. Other "Peeps" here would know better …

Now I understand, I think the host of problems is as long as your arm. Centering the tools to the lathe will be a pain, getting it perpendicular to the work piece will also. Lack of rigidity causing tool deflection will also be an issue. A mill spindle can possibly deflect in all directions. Combine just those problems using a toy lathe and part consistency from one to the next will be non existent.

digger doug said:

It is clear to me with these postings, that these new OP's are NOT
reading the guidelines as to what is and is NOT allowed here.

Can you blame them ? Look at each sub forum, and I see minimum
4 "stickies" up top. Given the attention span of todays posting
public.

The moderators need to clean these out, and Make ONE sticky, and make it clear
as to what is and is NOT allowed.

Click to expand...

I don't know if you noticed but it seems rule enforcement is very lax compared to days gone by. Look at all the people who sell here without participating.

Maybe we need to step up and bust balls hard enough that this stuff goes away.

aparfeno said:

Hello,
I am a hobbyist machinist and I wanted to get some advice or comments on the following idea/project:

I have a Grizzly G0765, 7x14 benchtop lathe, a toy really, that I can lift with one hand.
I also have a really nice Index Wells CNC 3000lb mill that works great under mach3 (2000oz steppers instead of servos).

Idea: bolt the lathe to the mill table, and use mill's X and Z axes to perform CNC operations on the lathe. I would need to make some toolholder that would hold a lathe tool in the spindle, and use mill's spindle brake to hold it steady.

I am also planing to upgrade lathe's bearings to taper bearings, something a lot of people with these lathes do.

So, I am curious if there are any unexpected problems that I would run into?
I am expecting that due mill's rigidity, I should get excellent surface finish and accuracy despite using this toy lathe. Am I right to expect this?

Thanks for any comments or suggestions,

Alex

Click to expand...

^^^
on "This Old Tony's" youtube channel he did some really good testing of the mini lathes with replaced bearing and gears and all that … But honestly surface finish and accuracy is … Well see for yourself. It's better... but … (see for yourself).

I have seen some youtube videos where someone puts a mini lathe on a gantry router …

Maybe "Bug" "This old Tony" he seems to have his head screwed on straight.


TORMACH do sell here so you can see their approach on their website.

Maybe search the patent literature for the "Duality-lathe." .


most of the folks that do custom or unusual machine hacks (here are of a very different skillset/ experience.).




So someone like Robrenz ^^^ having worked in ultra precision systems in one sort of way or another is doing a custom re-build of Mitsui surface grinder that will be way more sensitive and potentially more accurate than the original machine (using innovative CNC techniques that are of a lower budget)… He's a very skilled toolmaker and more besides but in a completely different league from your "CNC-hobby-ist". It's not always the case that folks have to be running hundred of thousands to millions of dollars worth of equipment to "Be here".

But in general this site is dedicated to pretty damn serious work (i.e. professional work) in a professional/ commercial environment or at least leaning strongly in that direction. So consequently folks here are not going to be that helpful or knowledgeable about "Hobby" machine hacks.

There is guy here who is building bench top machinery that is kinda mill turn. Search 'GenericDefault" is his handle, and the machines he is building I believe are called a "Swissmac ? " Is that right (sounds like kind of cheeseburger ? ).. . ???

___________________________________________________________________________________________________


@apefino Just word to the wise some "peeps" on this site don't want to see it become consumed by tens of thousands of hobbyists and hence kinda get a bit violent towards hard core hobby-ists. There was a time when even talking about Tormachs would be almost banned and now they are a sponser I guess that's much more allowed than it used to be... ?

The word "Gr----I----z--- (fill in the blanks) is pretty much an automatic disqualification around here/ fair game / open season to be kicked out , shot down, shredded and stomped on.

Dualkit said:

I don't know if you noticed but it seems rule enforcement is very lax compared to days gone by. Look at all the people who sell here without participating.

Click to expand...

Yes I agree completely, but as we have received feedback from disgruntled first timers that get their postings locked, where are clearly defined rules ?

For example maybe a list like this:
1. No grizzly
2. No mach 3
3. No stepper motors

Etc.

Also, this software ruling that won't allow posting a link to cnc zone dot com
is simply childish.

Along with the Harry Homeshop peanut gallery getting all bent out of shape with
me whenever I suggest a new poster try over at Home Page - Projects and Articles on Our Forum! | The Hobby-Machinist

Isn't it better to help a newby get some answers (at an appropriate website), rather than get a post locked and get butt hurt here ?

Thank you Dualkit, I believe your answer is the first one "on point". I was planning to add some kind of adjusting feature to the bottom of the lathe to index it against the*table*so that I'll be able to square it once and have repeatable results. Since i am using a cnc*mill, i think it should not be too hard to center the*tools and use gcode offsets for*various tools.

Here's Old Tony video from which i got my idea. He is using a gantry*router*while i have a*big*iron*mill. So i expect better results. CNC LATHE?! - Router Add-On! - YouTube

@OP,

No more about this please. If you wish to pursue answers about your idea, please go to a hobby machine focused forum.

Doug said:

...What the OP is suggesting is not necessarily a hobby activity. Where he went wrong was mentioning Grizzly.,,,

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Yet in the very first line of the first post he declares himself to be a hobby machinist...

Doug said:

.....Where he went wrong was mentioning Grizzly......

Click to expand...

And noting that it is a toy machine, and mentioning that his "big iron" is a mach3 and stepper motor hack on an old knee mill.

Threads like this need to be quashed early. That way if folks searching find this forum when looking for things about toy machines and hack retrofits, they'll see that those are not what this forum is about and move on.

I sincerely apologize for posting unworthy content to this forum. I was looking for professional advice, and figured this is the place to find it.

I am, however, happy, that my thread caused such a prolific discussion on demerits of unprofessional questions asked on this forum! I am glad that people found the time to share their much needed commentary.

No more from me

Vancbiker said:

And noting that it is a toy machine, and mentioning that his "big iron" is a mach3 and stepper motor hack on an old knee mill.

Threads like this need to be quashed early. That way if folks searching find this forum when looking for things about toy machines and hack retrofits, they'll see that those are not what this forum is about and move on.

Click to expand...

This brings up another point.

Newbies that don't take the time to "look around first" and post
in-appropriate threads, also have cited these "locked" threads
as being reasons why they think their post is O.K. to do.

"Bad" threads simply need deleted, not "Locked".

Booze Daily said:

Maybe we need to step up and bust balls hard enough that this stuff goes away.

Click to expand...

That's just internet bullying.

aparfeno said:

I sincerely apologize for posting unworthy content to this forum. I was looking for professional advice, and figured this is the place to find it.

I am, however, happy, that my thread caused such a prolific discussion on demerits of unprofessional questions asked on this forum! I am glad that people found the time to share their much needed commentary.

No more from me

Click to expand...

And here we have the typical response from the OP, angry and hurt.

To the OP, stick around, and READ & LEARN.

Many Members here will give you the shirt off their back to help a newbie.
However, not following the rules, shows ignorance on your part.

And many here get real offended by these kinds of actions.

As most people would, if were were talking face-to-face.