Author Topic: Pros and Cons of home shop CNC  (Read 2447 times)

Offline Jasonb

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Pros and Cons of home shop CNC
« on: January 30, 2023, 07:24:15 PM »
Prompted by some comments on my James Coombes thread I thought I would start another for general discussions about the use of CNC machines in the home workshop.

The point raised was about how long it takes to machine a part compared to castings . This can have several different answers.

If the casting is readily available and assuming no hard spots, defects such as being undersize or having bosses that don't line up with hole positions then generally machining the casting would take less time as you may simply need to flatten the top & bottom and drill/tap a few holes if we take a typical sole plate or bed casting as an example. But if a lot of fettling and reworking is required then time differences will start to reduce

On the other hand if you are making something to your own design or replicating an old long out of production model then using the CNC to cut from solid will quite probably be quicker than making your own patterns, having castings done if you don't have your own facilities and then there is the actual machining to be added on so in this case the CNC is likely to come out the quickest. Though for those that do want to use castings the CNC is just as happy machining wooden, plastic or even metal patterns and can be quicker than traditional woodworking methods as well as very accurate.

It was then questioned how machining a part on the CNC compared to a built up fabrication. This is another where there is no easy answer as each part will be different and depending on what the user has to hand in the way of materials and machines will dictate what is best for them to produce the part in question. Some parts will be better suited to cutting from solid, others better built up with manually machined parts but a lot of the time a combination of the two works out to be the best option using the CNC for things that it is best at like cutting curved components for the fabrication, the lathe to do round parts and maybe the manual mill for simple flat, square and rectangular bits.

The CNC's ability to cut quite complex shapes from solid can also be an advantage where a specific material is required. For example it is easy to silver solder a steel fabrication together but what if you want that crankcase to be aluminium or cylinder head in iron both of which are not so easy to join. So the CNC will be faster than manually carving the part from solid.

I'm probably in a bit of a unique situation, I was originally approached a few years ago asking if I would like a KX-1 size mill. After giving it some thought I said now based on what I had seen at a couple of shows where the guys demonstrating their CNC machines seemed to take an age to perform the simplest of 2D operations that I could have done in a fraction of the time on a manual machine. I also did not fancy having to learn "G-Code" that I had heard about and it all seemed quite daunting.

Moving on a couple more years I was again asked if I would like a CNC, this time the larger KX-3, this one being a customer return. by this time I'd seen a bit of CAM in use and was more proficient at CAD so decided to take up the offer, after all it was only going to cost me a Mach licence and reconditioned PC so no great loss if I did not like it.

Most will have seen my Darkside thread about my journey into CNC and having used it now for a couple of years I'm glad I accepted the offer. Although I still enjoy using the manual machines the CNC is really just another tool and I tend to use it for the things it excels at and don't have any intension of going over to a fully CNC workshop though it does seem to work for others.

To be continued


Offline Jasonb

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Re: Pros and Cons of home shop CNC
« Reply #1 on: January 30, 2023, 08:05:10 PM »
Carrying on with the time question there are also some other factors that should be considered.

At the moment you can't just go out and buy or download the code that the CNC needs to produce a part let alone a whole model. So you need to produce a 2D or more often these days a 3D model of the required part, not really an additional time addition for me as I was designing or redrawing existing designs to be built on the manual machines before I got the CNC. However if you are used to working from others plans then you will need to draw these up in CAD which depending on how proficient you are will add time to the overall picture.

But that is not all, once you have your part drawn you need to tell the CNC how to machine it, some may choose to do this by writing out the G-code themselves which depending on teh complexity of the part could be a few lines or thousands. However I think anyone venturing down the CNC route these days will opt to use some form of CAM which simplifies the production of the G-code. This is the way I have done it from the start and with all the items I have produced have not written a single line of G-code so don't let the thought of it put you off like it did for me.

Even with CAM you do still need to have an understanding of milling as the CAM although it may have some presets for various cutters and materials will need to have these tweaked to suit the users individual machine and the cutters you actually have.

Which brings us nicely onto another variable that has a big effect on how long a job may take on the CNC, which is the capability of the various machines. In the home workshop machines are likely to fall into three catagories. Gantry type router, converted manual or purpose made machine.

The gantry machines often fitted with small DC motors at the smaller end of the scale through routers to spindle motors at the top of the range. These can often be the cheapest option into CNC but are often of fairly lightweight construction so are not that efficient at cutting metal particularly steel or iron. If you do want to cut metal with these particularly the entry level ones then very light cuts are needed which means the cutter has to make many passes so the run time can become very long.

Converted machines suit quite a few particularly if you are able to build them up yourself. Being based on manual mills they will have the rigidity to cut all metals. Their biggest downfall is likely to be maximum spindle speed which will have an effect on feed rates for a given chip load. For example the majority of manual mills are likely to have a spindle that can run up to around 2000rrpm, maybe not too bad if you just want to profile a piece of sheet to a fancy shape with HSS tools but when it comes to using smaller diameter tools to machine complex three dimensional curved surfaces then these slow feed rates will see the converted machine needing to be run for a long time to complete a part. Though there are some benchtop mills on the market now with spindle speeds of 5000rpm which would be ideal for conversion and using carbide tooling

Purpose design machines are going to be the fasted option be that a new machine or an old one with updated software, drivers etc. These will generally be solidly built with spindle speeds of 5-10Krpm which allows faster feed rates and would reduce machining times to 20-40% of a typical converted manual mill.

Whatever type of mill CNC is being used in the home workshop it is unlikely to be able to perform like a commercial machining centre due to a combination of rigidity and power so metal removal rates will be less than they can manage. Comparing like for like size machines a CNC one is likely to be able to remove metal faster than a manual one not least because you can't physically wind the handles fast enough but also the tool is always on the move even at corners or other changes of direction. For example if you manually machine out a rectangular pocket you are likely to slow down your hand feed as you approach each corner watching the DRO readout, lock one axis , unlock the other and then go through the same again for the next side. The CNC will move constantly from one instant change of direction to the other and there is no risk of it overrunning which is all too easy on the manual machine. The added bonus is that you don't end up with the tool rubbing as it slows into to the corners which wears the tool.

Enough for now, hopefully a few others with CNC will chip in or if you don't have one feel free to ask any questions.

M

Offline Jo

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Re: Pros and Cons of home shop CNC
« Reply #2 on: January 30, 2023, 08:24:07 PM »
Lots of words there JB :noidea: 

In the beginning: Some stuff for model engines was originally made with castings, some stuff would be a difficult casting (like a table with the fancy bits that chill) and they can be made up in layers. Some members make some amazing stuff by twiddling the handles on their manual machines (Crueby, gbritnell, Ramon to name a few). All models have other bits that are made using a lathe or milling machine manually.

And then the world changed... We gained CNC  :headscratch: We now have members like Vixen building really complex model engines using their stable of CNC milling machines  :paranoia: And others like Jason using his to make models which would previously been done by more traditional means. I can't recall anyone showing off their CNC lathe (I know Vixen was looking in to it). I assume these models also require bits made by traditional hand milling/turning


So what are the good points, the bad points and the ugly points of CNC? This is a comparison with other more traditional techniques for making a one off model for a hobby not as a business.

I know that Vixen claims his CNC can be very Artistic  :lolb: and applies features to his parts to keep him on his toes.

I am going to claim price is an Ugly point  ::)

Jo




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Offline Jasonb

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Re: Pros and Cons of home shop CNC
« Reply #3 on: January 30, 2023, 08:45:02 PM »
I'm sure I have seen Vixen's Emco based CNC lathe in action in a number of his posts

Offline vtsteam

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Re: Pros and Cons of home shop CNC
« Reply #4 on: January 30, 2023, 09:09:45 PM »
I have a fairly eclectic view since I both cast and have some cnc facilities, but have never bought a casting. And that view is, I do what is pleasurable to me. I do love to cast metal, and I do love to make patterns, so I don't account the time involved as getting in the way of what I want to accomplish.

I can't say I enjoy CNC milling, but then I don't really enjoy hand milling much either. That's just personal. I do love working with the lathe, and I am quite certain I don't want to convert my lathe to CNC, because that would (for me) take the fun out of it and the challenge.

Because I have no call for production, repetition with the lathe isn't generally needed. I imagine if I were into production, all would be different.

I will say (and it takes a reversal of a former "attitude" on my part) that I did enjoy making my first pattern using a 3D printer this fall, BUT, I still did a lot of hand work with that, including filling sanding and painting. AND, I have no wish to eliminatethe extra time they involve either. Those are tasks that I put into every pattern, and I actually like them, and the final result.

What I liked about the 3D printed pattern was being able to make a relatively thin pattern with a hollow torroidal shape -- which would have been very difficult to execute in wood. I would never however want to stop making wooden patterns that are easier conventional shapes. I am through long practice, very fast at making and finishing a pattern, as well as casting. I can make a simple pattern, fill, sand, paint and have cast it in about 4 hours when I'm really interested. And I like all aspects of that. A small 3D printed pattern takes much longer -- at least the first one I tried did, but its complexity made it advantageous.

So, conclusion? Uh well frankly I like both oranges and apples, and I don't think one will ever replace the other for me because they are different. I do particularly enjoy manual skills, and do not want a computer to do things for me in general, but I also appreciate the option to do some complex things with assistance from CNC, as long as it doesn't take over as a substitute for my actually physically making things.

As for my opinion of others work in CNC. I absolutely enjoy seeing good work, by whatever method, and have been truly amazed at some of the models I've seen here. I know how much work, programming, foresight, research, skill, goes into making those models, and I honor them no less than I do pure manual works.

To me it's all about each person finding the niche they enjoy the most, and I'm frankly glad we're all a bunch of individuals with different joys in what we do. I am nowhere near as skillful as many people here, and yet I see that here, we all seem to appreciate the full range of abilities, experience, and personal interests we express in the works we show here.
Steve

Offline Kim

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Re: Pros and Cons of home shop CNC
« Reply #5 on: January 30, 2023, 11:44:13 PM »
Well said, Steve!  I tend to agree with what you said there.

I also like what Jason said - CNC is a tool, and if you have it, it's a great way to do some things.  Some people (like Williy) like to use files and hand saws for as much of his work as possible.  For me, that wouldn't be fun.  While I have those tools, and I use them from time to time, I don't do all may shaping with files and hand saws.  CNC is no different.  If you have the tool there are many great ways it can be used!  It is, however, a tool that requires a steep learning curve.

My closest brush with CNC is a 3D printer.  Has a lot of the similar up front CAD and gcode issues of CNC, and has a pretty steep learning curve for it to become useful.  But it's great for some things.  Plus, (and this is the most important part, which ties in with what Steve said) I'm having a lot of fun learning it and using it!

Maybe someday, I'll get into CNC.  But for now, I'm happily enjoying working with the manual machines that I have now.

Interesting discussion.  :ThumbsUp: :popcorn:

Beyond Steve's point about it being all about fun (which it is) I'm fascinated to hear the thoughts of people on when CNC is the right tool for the job.  Maybe it will convince me that I have to get into CNC next.  :Lol:

Kim

Offline Dave Otto

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Re: Pros and Cons of home shop CNC
« Reply #6 on: January 31, 2023, 12:19:38 AM »
I really enjoy the whole CNC process, CAD, CAM, and running parts. I got into CNC about 24 years ago by purchasing a kit and converting my Bridgeport clone mill. This was a stepper based kit and only 2 axis. I taught myself to run it and also how to use a really early version of BobCAD. I ran this way for around 10 years and made lots of parts with that setup. I always dreamed of having a full 3 axis machine so I started planning, buying parts and fabricating new hardware. Attached are some pictures of my control setup. I was able to purchase a second hand Elrod quill drive unit that bolted right up to my machine. Part of the upgrade was to ditch the noisy slow stepper motors and replace them with servo motors.

I guess the one con that I can think of is this is my only mill so everything I do, I have to do it on the CNC. But you do get used to using the jog control for quick jobs or entering a few lines of G code.

Yes and you can machine castings using the CNC, My Pacific, Essex and now KyKo engines are all done on my CNC mill.

I don’t have a lot of need for a CNC lathe in my home shop. I do have access to one at work and have used it to make a few engine parts, but they could have also been done on my manual at home.

Dave

Offline Woodguy

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Re: Pros and Cons of home shop CNC
« Reply #7 on: January 31, 2023, 12:37:36 AM »
One point to note in favor of home shop cnc. Taking as an example the MEM corliss cylinder block. While I drilled and tapped every hole manually, preferring to "feel" the operations, All the positioning was done rapidly and accurately by cnc.


I got into cnc because I wanted power feeds on all axes of my SX3 mill. By the time one adds up the cost, it wasn't a lot more to cnc convert the thing.  I still use the mill manually but I push a button - no crank turning.

Offline Mike R

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Re: Pros and Cons of home shop CNC
« Reply #8 on: January 31, 2023, 04:05:05 AM »
I fall into the “conversion” camp, with both a mill and a lathe.
The mill came first about 12 years ago.  I'd had a 3-in-1 lathe and mill/drill and wanted something more so I bought a large “bench top” mill and converted it right away to cnc.  It was partly for the challenge of doing it, partly cause I wanted a cnc mill and couldn't afford the single shot cost of a commercial mill. Back then a Tormach 1100 being the comparable size I wanted was over $20000 delivered in local bucks. In the end I had an all in conversion cost of ~ $4000 so that much was a success.  I've subsequently probably put another $1000 or so on incremental improvements and add-ons (but I don't keep track on purpose).
Later on I picked up a small Emco Compact 5 CNC lathe, and while its controls worked, they were too antiquated to work with newer software (tape drive for programs) so I updated its control system to be the same as the mills (only need to learn 1 control system).
I learned a great deal doing the conversion, and have become very familiar with various pros and cons of different aspects of small / hobby CNC machines.
I will say up front – doing a conversion of a machine can be a significant project in its own right, especially for larger machines and if you have no prior experience or mentor.
Honestly I enjoy doing it so much I'd convert more machines, except for the cost and lack of space!
As far as usefulness – I had (still have) the goal of making a 1/6 scale 9 cylinder radial. Lots of interesting geometry and repetitive operations that I thought CNC would be great for (and is!).
For the mill, I kept the quill and still use it to hand feed drills when I don't want the CNC doing it as I haven't a clue to the correct feed rate.  And its nice to use it to position things (bolt circles) for tapping by hand.
As I learn, I'm becoming more pragmatic and some things I just do manually as opposed to setting up a program.  One issue is having access to a decent CAD / CAM program.  That is where there's lots of time savings to be had as an amateur that doesn't use it frequently.  I'm sure that if I used it more I'd learn more tricks to be faster in programming but for now I'm pretty slow.  Also, not to turn this thread into a what software to use discussion but I'm leaning towards buying Alibre Workshop bundle (Alibre Atom and MeshCam) at the moment as a way of escaping from Fusion360 ever dwindling free offering. It looks like the 3-axis CAM (Meshcam) is really easy – so hopefully that makes it easier to get off the PC and hop into the shop to make stuff.
I won't go into the gory details of the conversions here, but I can create a thread if anyone's interested.
Mill is a clone of the Rong-Fu 12Z  travels 24”X ,9”Y , 18”Z after conversion.
Control system is MESA 7i76E card and LinuxCNC V2.8
Lathe – Emco Compact 5
Control is also the MESA 7i76E and LinuxCNC V2.8

 
So getting back to Pros and Cons:
Pros
 
  • built in DRO when using manually, easy to return to know positions (don't need to count the handle turns!)
  • Can program up curves and other difficult or impossible to manually machine shapes
  • Make repetitive tasks easier / more reliable (added 4th axis for gear cutting)
  • can help improve surface finish by having a very steady and appropriate feed rate.
  • Can pretty much do everything a manual machine can – except provide tactile feedback to the user.
Cons
 
  • Faster and more efficient breakage of end mills
  • Faster conversion of bar stock to scrap metal
  • Giant rabbit hole to get sucked into learning about everything cnc (feed rates, machine rigidity, steppers vs servos, control systems, CAM, CAD, spindle speeds, VFDs, 4th axis, etc.)
  • no tactile feedback – need to learn feeds and speeds to keep scrap / tool breakage low.
  • No avantage to CNC for many one off, relatively straight forward operations (though “conversational” programming at the mill can help speed up things)

Offline mikemill

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Re: Pros and Cons of home shop CNC
« Reply #9 on: January 31, 2023, 09:53:30 AM »
I have enjoyed being a model engineer for over 50 years, I bought my X3 CNC mill eleven years ago and enjoyed using it ever since.
I now build G3 model railway engines (can’t fit any more 5inG engines in the house)

Using CNC allows me to buld models that would cost many thousands for a few hundred, the whole process of researching the prototype, drawing the parts, machining them and final assembly is a joy.

Yes, the initial cost of a CNC mill is high but you will get your money back many times over by creating models that are not commercially available and just sheer enjoyment, after all that why we peruse the hobby.

Mike


Offline Alex

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Re: Pros and Cons of home shop CNC
« Reply #10 on: January 31, 2023, 01:47:54 PM »
I've seen MikeR's work, and workshop, and it's great. As is his work.

I've been CNC'd at home (mills, lathe(s)) since 2010 or 2011. All LinuxCNC based; even my KX1.

I don't understand why more people don't CNC mill. I do have 1 manual mill still (a Centec 2B) that I use sometimes, but honestly, I use one of my CNCs more, even if manually milling or drilling. For instance, drilling 0.025" holes in steel/Bronze last night, did it on one of my CNCs, with one of those spring-loaded sensitive drilling things, because it could easily get the spindle revs way up.

I'm not sure about lathes though - you generally need lots of accuracy, so right now, my last CNC lathe is used with steppers removed.

I have used my larger mill as a lathe - I think it was published in an article in Model Engineer regarding the making of bronze bells a while ago. Tools held in a vice on the table. Turned a headlight reflector in the same way.

For CAD, QCad, 2.5D. It works (very well) for what I want to do - take existing plans, assumes bar stock, and machines them. Last major job was locomotive coupling and connecting rods, CNC the outline, then CNC the thickness reduction and fluiting of rods. I've made chain links in QCad, with a "rotate" manually added, and these little links made without tool-changes. (again, written up in Model Engineer a while ago now)

I do have Alibre Atom3D, and Meshcam, but it's tied tightly to Windows, and my last Windows machine went into storage years ago. Now it's QCad, CamBam, running on a Mac M1, and even FreeCAD, running when I want to use it (but QCad is the "go-to" as it's faster to use for what I do). CamBam runs in a virtual machine, and it's pretty transparent in operation. 

I'm not against 3D CAD; lots of my well-paid-employment revolved (and still does as a contractor) around 3D rendering and writing of 3D rendering code. I use what I find the easiest and quickest for my workshop jobs - whatever you use is fine. (if you want to talk about Quaternions, scene-graph traversal, avatar-object collision vector detection code, GLSL shaders, etc, etc... sure! but Model Engineering is more fun)

Pros and Cons? I don't think there's any cons!

Offline Alex

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Re: Pros and Cons of home shop CNC
« Reply #11 on: January 31, 2023, 02:02:42 PM »
Mike;

Cons: No avantage to CNC for many one off, relatively straight forward operations (though “conversational” programming at the mill can help speed up things)

One place where prototypes were made had zero CNC mills. The workshop was about the size of 2 basketball courts, one of the machines was huge - well over a story tall. CNC allowed the machinists to do mundane operations quickly (e.g. conversational programming, as you mentioned) and accurately (e.g. placing and boring for push-fit ball races) and the machinists there could not believe that I'd still own a manual milling machine! That was the eye-opener for me.

For LinuxCNC, there is a package, called "Features" by Fern or something like that, which is great for conversational milling, and maybe turning, but I did have Andy Pug's Lathe Macros on my little Unimat SL now owned by another club member, and on my Sherline lathe (when I put the steppers back on after getting used to how it cuts by hand)


 

Offline Jasonb

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Re: Pros and Cons of home shop CNC
« Reply #12 on: January 31, 2023, 03:50:49 PM »
Lots of interesting posts.

Jo, Price can be considered a con but will depend on where you decide to enter the market be it a 3040 gantry for a few hundred quid to a plug and play hobby CNC like wabeco or Sieg. may not be much more than the combined cost of several mills and lathes that some people have in their workshops.

Alex mentions No advantage for many one off jobs is a con, agree that for straightforward parts there is not much difference but that is far outweighed by the pros of what a CNC can do for more complex one off jobs. For example I've spent several weeks of workshop time manually carving crankcases out of blocks of aluminium that the CNC can easily do in a day and most of that time I don't even need to be stood in front of the machine.

I've mentioned the learning curve which I suppose is a con but most going into CNC are likely to already be using CAD and if the same provider has a CAM package then it will be easier to find your way about.

For me the pros are the 3D ability as quite a few things I make need that rather than just using it to cut out a bit of plate or drill a pattern of holes, There were several engines that I fancied doing but had put off due to the complexity of manually machining some of the parts that I have now made since getting the CNC so to me that is a big Pro.

Finish was mentioned in one of the posts, the constant speed of feed certainly helps with this as does the ability to climb mill which usually gives a better surface finish. You can just use climb to do a final finish pass or two around a contour or I tend to use it for almost everything as the machine sounds happier cutting that way. So that's another pro. Also linked to that is you can machine in both directions if you want so no time wasted cranking the table back to the opposite end of the job to start another pass.

Linked to the above is that a CNC mill is in effect a mill with power feed on all three axis which most of us don't have so if you have a lumpy casting that needs boring and can't easily be held on the lathe you can get a nice constant feed of your boring head, pro again.

I'll list a few more later but have an appointment with a mug of tea right now.

Offline Jo

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Re: Pros and Cons of home shop CNC
« Reply #13 on: January 31, 2023, 04:20:01 PM »

Jo, Price can be considered a con but will depend on where you decide to enter the market be it a 3040 gantry for a few hundred quid to a plug and play hobby CNC like wabeco or Sieg. may not be much more than the combined cost of several mills and lathes that some people have in their workshops.


As you say equivalent to the combined costs of everything else :paranoia: Great if you acquire a bargain machine.

I recall how long it took to learn CAD. I assume CAM would be a simpler step. I still think of CNC as a separate hobby combining playing with computers  :killcomputer: with making lots of swarf.


For me its a bit like knitting: I started learning to knit by hand. In my late teens I brought a knitting machine. Yes there was the "programming" but having made possibly 20 or so jumpers on the machine I just found it boring. Knocking out jumpers did nothing for me. Years later all I do is hand knitting and I threw the knitting machine in the skip. The challenge for me is the hand skill, I also by commercial knitted jumpers from the shops - It is cheaper to buy a commercial jumper than to buy wool to knit one.

Jo


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Offline Hugh Currin

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Re: Pros and Cons of home shop CNC
« Reply #14 on: January 31, 2023, 04:30:19 PM »
In the late 1990s I adapted our (wife and I) touring bicycles to use small 22cc gas motors for power assist. (Worked great for mountain tours) Doing that I remade the fan side cover of the motor for better mounting options. This cover has a spiral shape that involves 6 or 8 different arcs. I did these on a rotary table. This "job" was the last push I needed to convert my mill to CNC. The mill is a 1960a SuperMax Mill from Taiwan, a Bridgeport copy. I converted X and Y starting in 2000 and the quill Z a few years later. Ball screws and stepper motors which are still in use. It uses a, vintage 2000, breakout board and Gecko stepper drives. That board is still in use but now connected using a Mesa 5I25 card. Many computers have cycled though. Control software has always been LinuxCNC (well back to when it was EMC). Back when it took me a week, 10 hours a day, to get EMC installed and working. Ah, the good old days.

I found the idea of a CNC lathe appealing. However, converting my 14" lathe to CNC was daunting. So, I found a Sherline lathe to convert and see how a CNC lathe fit my shop. Well, I found a great buy on a complete Sherline shop so ended up with a lot more equipment than just the lathe. I did convert the Sherline lathe and thought it promising. In 2017 we decided to take on full time RV life. I couldn't conceive of not having a shop so build the Sherline equipment into a traveling CNC mill/lathe combo machine. These used Sherline supplied conversion parts. It uses a Gecko 540 driver system from a parallel port. Again using LinuxCNC, which by 2018 was very easy to install and configure.

For various reasons the Traveling Sherline Show did not work out well. Chip all over the campsite was a big problem. But also it took maybe an hour to get it out and set it up. It worked fine but wasn't optimum in this use.

We now have a house in Prescott with the large machines set up. However we only spend a couple of months a year there. But we have a winter spot at an RV "Resort" in Arizona. So we can now have a permanent shed for a small machine shop and rock shop. I've been setting up the machines for a couple of years now. The mill is a Precision Mathews PM728 with PMs CNC conversion kit installed. The lathe is a PM1022 which I converted to CNC. Both use steppers and Gecko drivers. Both also use Mesa cards in the computers. I'm nearly set up enough to start building another model engine. As things go that will likely take us into March when we need to prepare for major summer travels. Yep, CNCs can take up a lot of time and energy. But just setting up a new shop takes a lot of energy and time.

My baseline is the knee mill and 14" lathe I've had since 1985. Compared to those I didn't get along well with the Shreline. For me Sherlines are too light. It could be me because I know many here use them with great success. But for machine tools mass is important. The winter shop bench mill and lathe look to have great promise. They need considerably lighter cuts than the larger machines and I'm still learning this. But I think they will work well for model sized projects. The machine has a dramatic effect on how long it takes to cut a part.

The machines are documented at www.currin.us if anyone is interested. However the bench top machines aren't there yet.

This is already long so I'll leave it here for now. I'd be glad to address any questions with my slanted propoganda and skewed truth.

Thanks if you made it this far. Have a great day in the shop.
Hugh

 

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