New to Machining

[artbylucas]

Hi!

Thank you for this opportunity to post!

My 1st post includes a couple of general questions!

I'm interested in doing thread cutting and general machining for the purpose of making telescope eyepieces and telescope tubes and mounts. Where should I start in buying a machine that can do moderately precision work? (I know, what is "moderately")!

I looked at Sherline, but it may be too small for some items. The South Bend
SB1001 and the Grizzly G9972Z are priced right. I think I will start with manual lathe/milling work then maybe jump to CNC in the future.

I've considered Grizzly tool room and gunsmith lathes, but still I'm TOTALLY in the dark over where to start and what to buy! Although, the SB1001 looks enticing plus it is light and movable to a 3rd floor workshop. Is it accurate enough?

Is there a lathe specifically designed for precision threading?

I'm all over the map with these questions! SORRY!

It seems like I may need to buy several machines to do all of the work that I have in mind as optics making can require close tolerances.

Your help in much appreciated!

Happy Holidays!
David Lucas

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[roundrocktom]

David,

Wonder over to Home Shop Machinist for some thoughts/feedback on what to buy.

I had hunted for a few years for a metal lathe. Finally found an "old iron" USA Leblond (built in 1942). It was too small (13" swing), had a tiny bed (only 18" between centers... it was built for Liberty ships, to fit between bulk heads). So it was just the "wrong machine" for what I imagined. Irony is almost 20 years later I'm still using it and never bought a bigger lathe. So remain flexible.

With a Telescope and mounts, I suspect most of your machining will be aluminum (6061).

The small G9972Z 11" x 26" Bench Lathe w/ Gearbox for $1600 isn't a bad starter deal. Buy it, and get to making parts. You'll still learn a lot and as time goes on it might be fine for what you need.

Since you are hanging out here, look into what machines people have fitted a CNC control to. I'd look there first for tips, and if it looks like that machine has been retrofitted, it will give you more options.

Nice thing with a lathe, usually you can resell it for 60% easily. So $1000 is reasonable, so if you upgrade in three years it only cost $200 a year. Nice a bad deal.

SInce you looked at the southbend, you might want to look at
G4002 12" x 24" Gear-Head, Cam Lock Spindle, Gap Bed Lathe $2600 machine, but should last you a long time.

I bought my 13" Lebond for $1000 in '95. Admitted we've had bit of inflation, but I could sell it for $1200 today. Catch is old made in USA is hard to find unless you are in the North Central or North East. I'll scan ebay and nothing for a year.... boom, then five lathes appear!

I've been at this for 20 years, and still have lots to learn.

Also post up your location. You might have a fellow machinist in the neighborhood.

[keithmcelhinney]

I bought a grizzly "starter" lathe (g4000) and not a day goes by that I wish I got something better. My motto is now to overbuy everything. You may be able to resell, but it is a hassle and you always have down time.

-Keith

[artbylucas]

Good points, Kieth! Much appreciated! Dave

[artbylucas]

Thanks for the useful information! Very Helpful! I'll try your ideas. Regards, David

[RICHARD ZASTROW]

David, You might like to look into Hardinge or Monarch 10EE. Rare, a bit pricey but if in decent shape, an heirloom.

Dick Z

[wizard]

Hi!

Thank you for this opportunity to post!

My 1st post includes a couple of general questions!

Welcome aboard.

I'm interested in doing thread cutting and general machining for the purpose of making telescope eyepieces and telescope tubes and mounts. Where should I start in buying a machine that can do moderately precision work? (I know, what is "moderately")!

Eyepieces are easy. The big question is the work on "tubes" which covers a wide array of sizes. An objective cell for a 70 mm objective is fairly easy on the smaller lathes, a cell for a 250 mm objective puts you in an entirely different category of lathe.

As to precision work that has a lot to do with the operator. Beyond that a "toolroom" quality lathe is far more expensive then the benchtops ou are looking at.

I looked at Sherline, but it may be too small for some items.

I would agree with that thought. It is a nice lathe no doubt but there are a couple of issues. For one you must have a lathe that supports threading if you expect to do a lot of optical work.

The South Bend
SB1001 and the Grizzly G9972Z are priced right. I think I will start with manual lathe/milling work then maybe jump to CNC in the future.

The SouthBend is new as such we are just getting reports on the lathes quality. I've only taken a quick glance at one and it does look like a very high quality machine. You have to consider how large the parts that you intend to work on will be. The lathe would likely be excellent for eyepieces and smaller objectives but might be far to small for large telescope work.

Here is the thing that might leave you frustrated, a smaller lathe is nice for working on eyepieces an extremely large lathe not so much. Especially if you are talking about a lathe to work on 250mm and larger objective cells. That would probably be a 14" or larger machine. So you might want to focus on what you are most interested in working on and how big you wish to go.

I've considered Grizzly tool room and gunsmith lathes, but still I'm TOTALLY in the dark over where to start and what to buy! Although, the SB1001 looks enticing plus it is light and movable to a 3rd floor workshop. Is it accurate enough?

Accuracy is up to you! The other issue with the third floor is weight. A lathe seriously larger then the SouthBend 8x18 could well weigh a ton. This is where it might be better to stay with a small lathe until you can get a ground floor shop. The problem as I see it is that you might need a fairly large lathe, to the point of having floor support issues, depending upon the size of the optics you want to work on.

The other thing is that it may very well be possible to do large objective cells on a CNC mill, though that mill might be fairly large itself. A CNC mill might be very valuable for this pursuit but then you have a big heavy mill sitting on the third floor.

Is there a lathe specifically designed for precision threading?

Threading is very important for optical work I will give you that. As for a lathe being designed for precision threading that would be a matter of the quality built into the lathe.

I'm all over the map with these questions! SORRY!

No problem. At least we know what you are making, that little bit of info helps a lot.

It seems like I may need to buy several machines to do all of the work that I have in mind as optics making can require close tolerances.

This could be a real possibility though a lot of optical work, eyepieces and such, are pretty much lathe projects. Good toolroom quality lathes are very expensive too, maybe as much as 40 times the prices you are looking at now. Further a machine that handles 5C collets is very handy for optical work.

Your help in much appreciated!

Happy Holidays!
David Lucas

A mill can also be a very useful tool in optical work especially if it is a CNC machine. You get into the same issue as with the lathe though, you need to make sure it is big enough to do the job but yet not so big the 3rd floor becomes a problem. Not to be forgotten is the weight of all the machines combined. I'm not certain what type of building that third floor is in nor how old it is but it weighs on my mind.

[wizard]

David, You might like to look into Hardinge or Monarch 10EE. Rare, a bit pricey but if in decent shape, an heirloom.

Dick Z

Grizzly is now shipping a ripoff of the HLV in this form: SB1008 Super Precision EVS Threading Collet Lathe. Not cheap, 3Phase and heavy.

However I must point out just how handy a machine with a 5C collet closer is for making parts for optical work. The problem there of course is that a lathe that supports 5C collets, with a thru spindle draw bar, are normally pretty expensive and big.

[artbylucas]

Much appreciated, Dick! I'll look at some on ebay.

Happy Holidays,
Dave

[artbylucas]

Thanks, Wizard! The 3rd floor room of mine is in a 160 years old brick house - very sturdy! I'm sure it would hold a half ton in one spot. But getting it up 3 flights would be no picnic! That is why I had a keen eye on the South Bend SB1001 plus it is "on-sale" at Grizzly for $2300 plus tax and shipping - say $2500. It weighs less than 300 lbs! But I think I will end up in my garage for all the really heavy stuff. But I will have to add heat! No big deal!

I still Have my eye on that G4003 12" x 36" Gear-Head, Cam Lock Spindle, Gap Bed Lathe instead of the SB1001 or the G9972Z 11" x 26" Bench Lathe w/ Gearbox.

For CNC milling I was considering the Sherline packages at around $3K, just to get my feet wet in this area (never did it!). So I figure about $6K about for both lathe and CNC and say about $3K for tooling. Sound logical?

What really throws a monkey wrench into any lathe, for my purposes, is that if you want to do larger diameters for thread cutting, you must end up buying a much longer lathe than you really need! I figure a 6" tube is the largest I would get into for refractor scopes since they don't get much larger than this. Plus, there is much interest and activity in solar telescopes and they are in the 3 to 4 inch diameter range with very short tubes - like 10 to 20 inches. Eyepieces are "1.25" and 2" diameter and no more than 6" in length.

Would you go with the G4003 or G9972Z instead of the new import South Bend? Do you think I am going in the right direction? There seems to be lot more bang for the buck with Grizzly from what I can see! But will it be accurate enough for fine threads and critical optical alignment?

Your opinion is much appreciated!

Dave

[wizard]

Thanks, Wizard! The 3rd floor room of mine is in a 160 years old brick house - very sturdy!

Don't count on it, inspect it! Seriously those old house have a lot of variability in them and at times third floor where an after thought.

I'm sure it would hold a half ton in one spot. But getting it up 3 flights would be no picnic!

No it isn't. Sadly a good lathe is all about the bed which is by default one piece and can not be taken apart like many mills can. Thus the bed is a good part of the machines weight that has to be moved in one go. All is not lost because people own refrigerators, sounds funny but refrigerator movers, that is hand trucks designed to climb stairs are just the nuts if you stay within capacity. Just remember everything has to be structurally sound all the way up.

That is why I had a keen eye on the South Bend SB1001 plus it is "on-sale" at Grizzly for $2300 plus tax and shipping - say $2500. It weighs less than 300 lbs! But I think I will end up in my garage for all the really heavy stuff. But I will have to add heat! No big deal!

It may be a bigger deal than you realize. Honestly if I was doing a lot of optical work I'd want to avoid doing it in a garage. Then again assembly should be separated some from machining, machining puts stuff in the air that can impact final assembly.

You really are saddled with a tuff choice here. I don't see a garage as a good place for optical work.

I still Have my eye on that G4003 12" x 36" Gear-Head, Cam Lock Spindle, Gap Bed Lathe instead of the SB1001 or the G9972Z 11" x 26" Bench Lathe w/ Gearbox.

The G4003 is a interesting machine and you can get it with a 5C collet closer. It isn't a small lathe nor is it really a big lathe. I'm almost to the point that I'm going to suggest getting the SB1001 to locate it inside. It isn't perfect by any means for some of your larger parts but it seems like a good fit for the bulk of your work. If things go well with this endeavor you could consider buying a decent CNC lathe for the garage. I'm assuming this is a business adventure where a CNC lathe might make sense. The thing with this path is this: once you buy the CNC you will still have the small SoutBend for secondary operations and non CNC work. The SB would be small enough not to take up excessive space but still be highly useful for any manual work you may need done.

If this isn't a business adventure then justifying hardware is a bit different.

For CNC milling I was considering the Sherline packages at around $3K, just to get my feet wet in this area (never did it!). So I figure about $6K about for both lathe and CNC and say about $3K for tooling. Sound logical?

No not really. However that reflects my interpretation of what you intend to do, which is building telescopes from the ground up. In that regard I just see the Sherline as too small to get the job done.

Also I'm not clear on what you are implying with respect to CNC. Frankly if you want a CNC lathe, buy a CNC lathe designed for CNC work. Why? Because in my opinion CNC lathe conversions aren't as flexible or viable as mill conversions. This has a lot to do with the mounting of tooling in a lathe conversion where manual lathes are highly optimized for a man at the machine. A CNC lathe will have the tooling turrets and other tooling solutions designed for the machine in question and as such they are a different animal.

Mill conversions are a bit different as they easily accommodate automation up to and including automatics tool changers. Thus a CNC conversion of a mill makes more sense to me. So if when you say CNC you mean a mill and not a lathe conversion then we are on the same page. The issue then becomes how large should that mill be? Again it depends on just what are your intentions here but making mounts and focusing mechanisms will probably require a fairly large mill. Such a mill, say a Tormach class mill, will take that $6000 and a whole bunch more.

What really throws a monkey wrench into any lathe, for my purposes, is that if you want to do larger diameters for thread cutting, you must end up buying a much longer lathe than you really need!

Yep that does suck a bit. If you look around a bit you can find lathes in the 12 to 14" class that are around 24" between centers but they are not easy to find.

I figure a 6" tube is the largest I would get into for refractor scopes since they don't get much larger than this. Plus, there is much interest and activity in solar telescopes and they are in the 3 to 4 inch diameter range with very short tubes - like 10 to 20 inches. Eyepieces are "1.25" and 2" diameter and no more than 6" in length.

The Little SB would likely struggle with the machining of a six inch objective cell but it might pass for prototype work. It would depend upon how well you could get external surface finishes. It would likely accel at machinng of eyepiece assemblies and such.

Would you go with the G4003 or G9972Z instead of the new import South Bend?

That is a really tough question to answer! If you will be starting out with that shop on the third floor then I'd lean toward the smaller machine. If this is a commercial adventure I'd seriously consider as my next purchase a real CNC lathe. A CNC lathe because so much of a telescope is or starts out being natural turning operations. If you think about eyepiece assemblies, objective assemblies and such these are almost pure lathe turned objects.

Do you think I am going in the right direction? There seems to be lot more bang for the buck with Grizzly from what I can see! But will it be accurate enough for fine threads and critical optical alignment?

Right direction? Hard to say as this sounds like something you intend to turn into a business adventure. If that is the case you can't rule out the wisdom of marketing use of contractors to get things off the ground. So then you have to figure out where it makes sense for you to add the most value to your product. It might make sense to have a contractor do larger objective cells until you are suitably equipped. Or it might make more sense to do large objective cells on a mill these days.

As far as Grizzly goes, they do have some good bargains and some no so impressive offers. You really should look around as I've bought equipment for Grizzly and a number of other source. It isn't just a matter of price the machine needs to fit the job at hand.

As to you concerns with accuracy, the machine has a function in that but so too does the operator. Frankly when looking at lathes in the price ranges you are you can't expect perfection. If you want to see a significant difference in quality it will cost you, just look at the prices on the Monarch 10EE (even used) or the Hardinge knockoffs. These are manual lathes yet people believe, with some justification, that they are worth it for precision work. As for optical work I've been in that industry for close to 30 years now and the Hardinge HLV lathes where more or less standard for manual light duty work. Can you do good work on lesser lathes for telescope optics - most certainly! There is little doubt in my mind about that. That is what skills are, you learn to leverage the tool at hand.

Your opinion is much appreciated!

Dave

Hey my name is Dave too!

As a footnote most of those HLV lathes have been replaced buy even higher precision CNC type machines. Precision can be a real b$tch to maintain at times and frankly people are forever confused when it comes to precision and resolution. Precision in manual machining relies a great deal on the machinist doing the machining. To put it bluntly I can screw up a part on a Hardinge just as easily as I can on my 9x20 at home.

[artbylucas]

WOW! I'm on information overload! You're a fountain of knowledge!! Much appreciated, Dave!

Give me a day or two to digest everything you covered!

But one quickie - I see a Hardinge DV59 Lathe on ebay (#160943179345) not too far away but still a truck shipment.

How would this unit do for me - it takes the 5C collet?

Regards,
Dave

[wizard]

WOW! I'm on information overload! You're a fountain of knowledge!! Much appreciated, Dave!

Not really my knowledge is highly biased from working in one place and one industry for far to long.

Give me a day or two to digest everything you covered!

In the end you need to make your own decisions and focus tightly on what you are interested in. For example I know of people that got started in the telescope business making focusers and still do to the last of my knowledge. One of these guys I hade an extensive conversation with some years ago. Focusers obviously require much in the way of milling operations and in this regard he started out with a home brew CNC mill. He quickly migrated to Haas mills as a home brew doesn't really cut it for mass production and wasting time on conversions can take focus off your business

But one quickie - I see a Hardinge DV59 Lathe on ebay (#160943179345) not too far away but still a truck shipment.

No don't go that route. DV59 are second operation machines and don't support threading or even feeds. These lathes are very popular still as they are rugged and often are employed for very specific operations. You will see many of them modified or adapted to do single operations.

How would this unit do for me - it takes the 5C collet?

You don't want a DV59 for your first machine. Hardinge doesn't make the secondary operation lathes anymore to the best of my knowledge anyways. These guys make knock offs: cyclematic toolroom lathe Precision lathe small lathe ???? ???? ???? ???? ????, I'd be reluctant to even guess how much one would cost anymore.

Interestingly they have some CNC solutions built around HLV type machines. I suspect one of these lathes would blow your budget pretty bad.

Regards,
Dave

A couple of more thoughts. It will cost a small fortune to tool up to make an entire telescope of your own design. It might make more sense to "focus" on one component that you can excel at and hopefully ramp a business from there. If you are thinking eyepieces you have some rather huge hurdles to get over due to some really high quality competition. Perfect something that can be easily transferred to production on a low cost CNC lathe.

One more thing; many here would suggest doing your development work on a commercial CNC machine right from the start. This isn't a bad idea at all, but it is expensive and installing a suitable machine in your garage will not be easy. Considering a conversion of a manual machine is problematic in my opinion due to the tool changes required and the lack of room to gang tools up. I suppose you could manually change the tools on an Aloris style tool post but that sort of defeats one of the advantages of CNC. There are other considerations too, so I'm not convinced you are at a point where investing in a CNC machine is wise. There are many types and configurations to choose from.

Haas has their TL-1 machines that are one example of a CNC machine that could easily be setup in a garage. They list that machine for $25,000 base price with a whole bunch of required upgrades. This gives you an idea of just how much money you are talking about for one brand new commercial solution. They also have their "office" mill that can go into a garage easily. It is a bit more expensive.

These prices on new is why many guys in these forums convert old CNC machines to PC based controls. Effectively replacing old broken control systems on machines offered up cheap. You still have the real issues of how to power such machines in a home garage though. The problem is the conversions themselves aren't cheap and further it will take you a long time.

[RICHARD ZASTROW]

OK, I live when we where real machinists (all us old farts say that). The Hardinge lathes were great machines. You want the engine lathes, not the second operation machines. I believe they have a threaded spindle nose that can mount both chucks and 5C collet adaptors.

I'd look into the Monarch 10EE tool room lathes. They have a bit larger capacity.

wiz is correct, they are pricey and the rest of his comments are also correct.

You will have to investigate all aspects of what you intend to do, how much investment it will require and if you can afford to do what you want.

We just did a study to determine the start up investment to replicate what we do. $2.5MM and 3 years before a paycheck!!!!!

Good thing my mind can't comprehend anything more than 4 digits.LOL But we do produce custom built machines for ~1/2 the price of our competition. It also produces terror, fun and keeps my aftermarket heart parts working.LOL

Dick Z

[wizard]

OK, I live when we where real machinists (all us old farts say that). The Hardinge lathes were great machines. You want the engine lathes, not the second operation machines. I believe they have a threaded spindle nose that can mount both chucks and 5C collet adaptors.

HLV have a taper for mounting chucks.

I'd look into the Monarch 10EE tool room lathes. They have a bit larger capacity.

You know I've never seen a Monarch 10EE in person, never. I probably should do something about that before I kick the bucket. It is nice to see they are still being made.

wiz is correct, they are pricey and the rest of his comments are also correct.

You will have to investigate all aspects of what you intend to do, how much investment it will require and if you can afford to do what you want.

We just did a study to determine the start up investment to replicate what we do. $2.5MM and 3 years before a paycheck!!!!!

I think I'm past investing in my own business. I do play with the idea of a "retirement" business, but have no idea what that would be.

Good thing my mind can't comprehend anything more than 4 digits.LOL But we do produce custom built machines for ~1/2 the price of our competition. It also produces terror, fun and keeps my aftermarket heart parts working.LOL

Dick Z

[artbylucas]

Again, much appreciated info, Dave. I'll continue digesting all of this.

Regards,
Dave

[artbylucas]

Thanks, Dick, for all the useful comments and information!

I'll continue my study of all these details.

Regards,
Dave

[artbylucas]

Another quick question, Dave:

Are the accessories for the South Bend SB1001 compatible with Grizzly or other common brands?

Manu thanks!
Dave

[artbylucas]

Hi Dick and Dave! How is a Myford Super 7 lathe with extras for $2850?

Myford Super 7 lathe with attachments

Thanks!
Dave

[wizard]

Another quick question, Dave:

Are the accessories for the South Bend SB1001 compatible with Grizzly or other common brands?

Manu thanks!
Dave

That depends upon the accessories. One nice thing about the SouthBend is that it has a standardized spindle nose. The bad thing is that it isn't the worlds most popular size nose. So for spindle tooling if it uses the D1-3** taper and otherwise fits then you are golden.

As for whatever else you should mean that most likely depends. Yes an escape from a concrete answer but required because well it depends. Some things are designed to fit a specific lathe and other things get fitted to a lathe.

** I think it is D1-3, apparently Grizzly web site is down.