CNC options?

[timo_gross]

I thimpfks you guys are nearly as crazy as me. I would look at all the auctions all over the country, mostly from the rust belt east and south to the Carolinas, for used manual mills in the Bridgeport style. There are scores of them. If I lived in that region, I woujld already have two or threee of them/ You could always fix up a CNC bit, and man;y of them already have DROs. It's MNSHO that it would be better to have a Bridgeport style, hunky mill, than any of the toy models, but then I'm not everyone and some only need those small models.

You are right on the one hand, on the other hand.
Restrictions are money as well as space, infrastructure and so on. ...... To put a full grown Bridgeport style in the living room is not everyones option.
Even transport can rule out a certain option.
Maybe you can pick up a 2nd hand WaldrichCoburg just for scrap value and pick up at the location.

Crappy infrastructure prohibits "real machines", from foundations to power to environmental and whatever restrictions you would have.

Then again they most people do not have the patient neighbours to cope with the router motor screaming for hours. But maybe that can be tackled with a soundproof enclosure.
It is all about figuring out needs, budgets $, time, patience.

Greetings Timo

 

[ajoeiam]

I thimpfks you guys are nearly as crazy as me. I would look at all the auctions all over the country, mostly from the rust belt east and south to the Carolinas, for used manual mills in the Bridgeport style. There are scores of them. If I lived in that region, I woujld already have two or threee of them/ You could always fix up a CNC bit, and man;y of them already have DROs. It's MNSHO that it would be better to have a Bridgeport style, hunky mill, than any of the toy models, but then I'm not everyone and some only need those small models.

Had thought of using auctions to get some bits and bobs for here.
Found that a lot of auction companies have some very very crazy requirements for bidding.
It was as bad as having to deposit $10k before being allowed to bid/register and then I was looking for tooling.
Also found that rigging prices tend to be absolutely astronomical and then some of the rigging outfits had no idea on what they were doing.
Getting them to move 1 pallet from site to my transportation was like $75 - - - - all of this quickly soured me on auctions.

Maybe better if one could attend in person but the online at some distance - - - - no longer interested!!

 

[Richard Hed]

Had thought of using auctions to get some bits and bobs for here.
Found that a lot of auction companies have some very very crazy requirements for bidding.
It was as bad as having to deposit $10k before being allowed to bid/register and then I was looking for tooling.
Also found that rigging prices tend to be absolutely astronomical and then some of the rigging outfits had no idea on what they were doing.
Getting them to move 1 pallet from site to my transportation was like $75 - - - - all of this quickly soured me on auctions.

Maybe better if one could attend in person but the online at some distance - - - - no longer interested!!

Yes, all that is true. But most auctions do not require a fee to register. You have to take in the state tax, the auctioneer's fee which is usually 18%, rigging, and shipping. then bid accordingly. That's why I recommend living close to the auction before bidding, so if you win the bid, you can have a truck ready to pick it up and not have it shipped. Calculate all the other stuff when you put in your final bid--do not go over it and you are fine. I bid exceptionally low but occassionally I win something. I won an oscilloscope two weeks ago for 10$. Nice, huh? But the shipping is 32$. Still I am getting the best part of the deal, a good oscilloscope for less than 50$!

 

[Bentwings]

I was always told that there are 3 key issues when choosing a mill (be it CNC or manual):- Rigidity, Rigidity, Rigidity!
perfect, I agree . Our little 10x22 lathe really struggles with anything tough like 4130 or. 4340. Plane old cold roll is gummy and tough to get good finish. The machine has a 3 phase motor which gives much more bower than the stock motor but the whole frame is simply not strong enough . The carriage has a little looseness that is really hard to adjust out. Probably because the bed is not really dead straight The milling machine has a pretty stout motor but with s large round column m it’s still not a Bridgeport Finishes are adequate for what is done with it but not “ real” machine tool quality . Lots of guys finesse things and get some really good work out of smaller shop tools but it takes some good skill levels to do this
OK, that's a simplification and a lot depends on the application. Router type "mills" lack rigidity and are fine for thin "soft" thin materials but with model making you quickly come up against 1/4inch thick sheets of hard brass and steel. I have a Sieg KX1 which only just manages to cut my parts. Unfortunately there seem to be few small CNC machines on the market (not sure if the KX1/3 are still available) apart from the router types which promise everything but deliver little to the model engineer. Router designs are easy to make - hence being widely available - but lack that vital ingredient of rigidity!

FYI I use Autocad and CamBan

Hope this helps to move the discussion along.

Mike

 

[awake]

Just to add another entry to your spreadsheet, you might consider either of the following; I don't have personal experience, but from what I've seen in videos, I would guess they should perform as well as (or better than?) the Nomad:

https://indystry.cc/indymill/https://docs.v1engineering.com/mpcnc/burly/

 

[peterl95124]

KQuiggle,
perhaps you're asking the wrong questions, the questions you might be asking are
is anyone making actual model engine parts with a toy (Sherline,Taig,etc) CNC mill ?
I suspect you'll find the answer to be effectively zero (except for ClickSpring, but
he's the exception that proves the rule, none of us mortals can do what he does
with or without CNC)
of the (few!) people that actually use CNC for model engine parts what do they use ?
I suspect you'll find the answer to be effectively nothing smaller than a Tormach, or Bridgeport clone/conversion and typically much larger like old Haas, etc

if all you want to do is learn CNC then start with (free for us hobbyists!!!) Fusion-360 as the CAD side is a steep learning curve no matter what iron you end up with.

if you get a toy CNC all you might really be learning is the limitations and workarounds for it, which probably won't be relevant to the real machine you might eventually end up with with different controller and different iron.

finally be realistic about what you're going to do with it, I've been building model engines for 30 years now and still don't see how I'd use CNC effectively. I don't think CAD is useful unless you want to machine from bar-stock something that looks like a casting with all its curves, fillets, mounting bosses, etc. and I don't think CNC is useful unless you're going to be making multiple copies of the part.


BUT, if you enjoy discussing options on forums then you're AOK, and if you can't afford the big iron and just want to get your feet wet with a toy you're AOK, its a hobby and what ever turns your crankshaft is AOK !!!

Peter.

 

[kquiggle]

Several comments :

• Bridgeport type machine - I would love to have one, with ot without CNC, but just not an option for me as my shop is in the basement with limited access.
• OneFinity and IndieMill - both nice machines, but more toward the router end of the spectrum. Not saying that's a bad thing, just not what I'm looking for.
• Various comments on CAM - lots of food for thought. I might look into playing around with LinixCNC just as a learning experience. I started teaching myself OnShape CAD a year before I bought my 3D printer, with the idea that unless I could use 3D CAD effectively, there was no point in getting a 3D printer (not saying that's true for everyone, but it was a key goal for me).

The comments about the "usefulness" of CNC are interesting, but if one of my goals is to learn CNC machining for it's own sake, and if pretty much everything I do is for hobby purposes (and the occasional "fixit" job), I'm not sure how it applies to me. In the end, for me it comes down to this : "Will the money and time I put into this pay me back in terms of learning something new and having fun doing it?"

Some comments on machines that have been discussed here :

Nomad : The more I look into, the more it looks like the user community is mostly doing "artistic" type of work (for some, as a business). More power to those people - I applaud makers of all kinds. But not where I want to go. The Nomad seems to be a good machine for that kind of work, and seems to handle soft metals reasonably well (aluminum, copper, some brass); it can do steel to a limited extent but that is pushing the boundaries of that machine. Ther are a lot of other pluses in terms of being a turn-key set-up with lots of support available. At this time, weighing the pluses and minuses from my point of view, I am leaning away from the Nomad. It's still on my "maybe" list, but not at the top.

DMC2 : The more I look at this machine, the more I like it, although I still have significant reservations. As I have researched actual owners, the video link below seems typical : The fit and finish of the parts is not great, there are issues that have to be worked around, and a fair amount of effort, tweaking, adjusting, and de-bugging is needed to get the machine working. On the plus side, the issues can be fixed, the adjustments can be made, and the bugs can be squashed. On the even more plus side - the machine has considerable capability for the price. In an odd way, the poor finish on the parts (like an aluminum plate that has been water-jet cut but not deburred) is a bit of a plus. Removing burrs and sharp edges is no big deal, and if I can save money by doing it myself I'm OK with that. As the saying goes, professionals spend money, hobbyists spend time.

Now clearly the DMC2 is anything but turn-key, but if I have to do a kit build to get something I can afford then I do not see that as a deal killer.

Haven't made a decision yet, but the DMC2 has moved up on my list.

Here's the video :

I bought the DMC2. Was it worth it?

 

[timo_gross]

Haven't made a decision yet, but the DMC2 has moved up on my list.

Here's the video :

I bought the DMC2. Was it worth it?

Bad pun, I can not help it: Instead of DMC you should look into DMG

 

[Jasonb]

Peter your assumptions about what can be produced on a toy are wrong, My KX=3 is smaller than a Tormek and as others say they are not accurate but I feel differently.

I do make parts that would otherwise be cast or actual patterns for castings and as I have said I used to do it on my manual machines which would take several weekends and evenings now I can do say a crankcase in an hour or two.

A few examples of what "toy" CNC machines can do.

Crankcase halves, timing nracket, stand, exhaust flange, carb body, rocker arms, conrod and iron cylinder head on this engine

Frame parts, cylinder parts, head, stand, steel flywheel, fan. conrod, etc on this one

If Steam is your thing then main frame and outrigger, bearing caps , iron flywheel, crank disc recess, pipe bends, etc

What about hot air engines, two main frames, all conrods and linkages, bearing caps, two Iron flywheels, lettering on cylinder jacket, sheet metal for base

All my own designs of engines where castings are no longer available or have never been available. I don't do barstock looking engines but do make use of a small CNC to replicate castings and other parts of engines starting with raw bar stock. All reference to Iron parts were cut from solid bar not cast from patterns

I've been making model engines for just over 40 years, only had the CNC for the last couple but would not want to be without it now as it opens up a lot more possibilities and I can replicate engine that I may have been put off off in the past that would have been too complex to carve manually or fabricate in appropriate materials.

So to anyone reading don't be put off that small benchtop machines can't be used to make engine parts, yes the vey small gantry machines will be more limited than the small mill style ones but if you take appropriate cuts and don't expect the speed of a DMG or Hermle you will be able to make model engine parts from them.

 

[Jasonb]

The "Toys" can also be used for pattern making which the gantry type macjines would be well suited to but even the benchtop mill ones like mine can make usable patterns, a few examples of what they are capable of below

 

[timo_gross]

Hello Jasonb,

The fotos of your engines show that it is not only the machine but also the operator who does the work. Some very big misconcepition with CNC, that there is no know how and operator experience involved.

I assume your machine looks like this one, is that correct?

That is very similar to my "horrible one", but some aspects are to it.
My machine was already 10 years old when I bought it, is not at all accurate, sloppy maintenance, wedges, chips in the ball screw nut, wear etc.
I guess with some effort it could (have been) be fixed. Not all lookalikes are actually assembled to the same Quality standard.

But if we are talking about this machine it is already much heavier and more capable. Not comparable to that "Nomad" or a shapethinggummy I think Peter was refering to.
For sure a different league. And the Gri..ly company wants 12k USD for one which is four times as much as the mentioned "toys".
Is a smaller Tormach so much different from that one, if the Enclosure is taken away?



Not as good looking, but also a product of the inaccurate mill. For the gear cutting the backlash is not a big issue, because the cutting direction does not change as much.

Greetings TImo

p.s. did you do anything to prevent chips and coolant fly everywhere?

 

[ajoeiam]

Yes, all that is true. But most auctions do not require a fee to register. You have to take in the state tax, the auctioneer's fee which is usually 18%, rigging, and shipping. then bid accordingly. That's why I recommend living close to the auction before bidding, so if you win the bid, you can have a truck ready to pick it up and not have it shipped. Calculate all the other stuff when you put in your final bid--do not go over it and you are fine. I bid exceptionally low but occassionally I win something. I won an oscilloscope two weeks ago for 10$. Nice, huh? But the shipping is 32$. Still I am getting the best part of the deal, a good oscilloscope for less than 50$!

Dunno about that "most auctions do not require a fee to register".

Likely no fee to register but if you want to bid then that's when all the requirements hit.
It was the requirement for large $$$$ deposits when I was looking at perhaps a few hundred $$ worth of tooling that totally turned me off!

Not a fee to register - - - they want you to register so they can bomb you with more auction bulletins - - - - they are quire hard to stop as well.
Somehow the unsubscribe works for a bit and then somehow - - - one is getting bulletins again.

My essay into this world really left a bad taste in my mouth.
I had bought auction stuff before but haven't even looked much since all this 'garbage'.
The auctions seemed mostly to be very large companies trying to unload a mothballed facility quickly with the auction companies (and their friends) trying to maximize their own results assuming that the scrap man was going to be their predominant customer.
Was a pity - - there were a few pallets worth of tooling that I would have liked to have gotten!

 

[Jasonb]

Timo, I'll take that a as complement but if I can do it so should anyone else. I don't have an engineering background and have not worked in that field and am just a self taught hobby user. The crankcase on that first engine with the orange paint was one of the first parts I made on the CNC, first item that I used F-360 CAM for and as you can see both halves were usable.

My size comments were aimed more at Peter who said

of the (few!) people that actually use CNC for model engine parts what do they use ?
I suspect you'll find the answer to be effectively nothing smaller than a Tormach, or Bridgeport clone/conversion and typically much larger like old Haas, etc

at 300mm x 135mm my X-Y envelope is 2/3rds that of a Tormach770 or 1/3rd that of a 1100 so I do consider my machine of smaller capacity than Tormach and certainly not "much larger"

Even if money were no object I don't think I would be looking for a much lager machine. As I said several page sago more Y movement would be nice so something like a Hass Compact CM-1 would be my ideal machine. It's their smallest mill but for the size of parts most of us are likely to need for model engines it's 12 x 10 x 12 envelope is big enough. It is more rigid, it is more powerful and generally of a higher standard. What it does offer is much faster rapids than my 1000mm/min (39ipm) and much faster spindle speeds so tools can be run at their optimum cutting speeds and therfore feed rates also go up and machining time comes down. They will also run fast enough for very small cutters which are what you need for machining complex parts like that Morton M5 cylinder head which would take a very long time even with my 5000rpm spindle. Also possible to get a small trunion for it so 5-axis is possible, again ideal for something like a heavily finned cylinder head.

I don't know where Peter has been looking and not seeing small machines being used. One only needs look at the start of this thread, in post #6 to see the post starter using an gantry type machine for engine parts

Or Bazzer's post #9 these parts find their way onto the world class competition model plane engines and I think he has also made small parts for America's cup yachts done on a Wabeco and gantry machine

If you want to see some more then pop over to MEM forum and look at Mike's work, he has done away with most of his manual machines just keeping one manual lathe for larger items. His CNC machines are the Compact 5 based ones and he does not use modern CAM but produces some award winning engines

https://www.modelenginemaker.com/index.php/topic,7559.msg189005.html#msg189005
https://www.modelenginemaker.com/index.php/topic,5142.msg256929.html#msg256929
Even the recent Westury based engine by "Eccentric" on here had the CNC work done with a gantry type machine

Lunch break over, I'll post about the KX-3 later

 

[stanstocker]

KQuiggle,
perhaps you're asking the wrong questions, the questions you might be asking are
is anyone making actual model engine parts with a toy (Sherline,Taig,etc) CNC mill ?
I suspect you'll find the answer to be effectively zero (except for ClickSpring, but
he's the exception that proves the rule, none of us mortals can do what he does
with or without CNC)
of the (few!) people that actually use CNC for model engine parts what do they use ?
I suspect you'll find the answer to be effectively nothing smaller than a Tormach, or Bridgeport clone/conversion and typically much larger like old Haas, etc

if all you want to do is learn CNC then start with (free for us hobbyists!!!) Fusion-360 as the CAD side is a steep learning curve no matter what iron you end up with.

if you get a toy CNC all you might really be learning is the limitations and workarounds for it, which probably won't be relevant to the real machine you might eventually end up with with different controller and different iron.

finally be realistic about what you're going to do with it, I've been building model engines for 30 years now and still don't see how I'd use CNC effectively. I don't think CAD is useful unless you want to machine from bar-stock something that looks like a casting with all its curves, fillets, mounting bosses, etc. and I don't think CNC is useful unless you're going to be making multiple copies of the part.


BUT, if you enjoy discussing options on forums then you're AOK, and if you can't afford the big iron and just want to get your feet wet with a toy you're AOK, its a hobby and what ever turns your crankshaft is AOK !!!

Peter.

Greetings,

Obviously CNC is not a requirement for making any of the classic model engineering projects, I tend to use it mostly for complex shapes that would make my shoulders hurt for days if I had to saw them out and file to shape, or long monotonous pain in the butt jobs. If you have CNC, it can save you lots of time turning handwheels for utterly boring needs. Some folks enjoy turning hand wheels for hour on end, and some will tell me "That's what the hobby is all about, why are you even here?". Probably because there's room for all sorts of folks in our world

I had a clock restoration business, and did parts work for other clock guys who didn't do much machine work. The first time you use a traditional dividing head and mill set up to cut out the spokes and teeth on a 96+ tooth gear it's a great feeling. The third time I said screw it and set up a Sherline four axis CNC mill. Those curvy front plate parts are perfect for scanning, tracing, and knocking out on a CNC mill, although they are every bit as functional and pretty done with a saw and files. Still use the manual approach for cutting pinions, the set up is trivial on a manual mill and it's not a long job. To be honest though, cutting pinions in steel is something I prefer to do on a larger mill, the vibration absorbing nature of the heavier table is beneficial. But if I didn't have a larger mill, the Sherline would do the job fine, just would take a few more passes to get the desired finish. Not model engineering I know, but in the scale of work often encountered in model engineering.

Most folks who make engines or models can't claim to have any reason to make them other than the pleasure of figuring things out, learning something weird about a given engine design, and the pleasure of doing persnickety stuff well. Honestly, what am I going to DO with another model boat? But still, there another one is out on one of the benches and in progress. My Quorn is about 90% done, but I'm having a hard time getting motivated to finish it, these days I'm all about carbide end mills and the motivation to complete the tool will have to involve me being too stubborn to quit rather than driven by need.

For me the building and tweaking part of CNC is more fun than the actual making of parts on a CNC machine. To use a CNC machine, it has to save me time or pain in my crappy shoulders. Hours of sawing or repetitive motion leaves me in pain, others find it relaxing to spend hours cutting out the frames for a skeleton clock, gives them a chance to let the mind wander a bit and just enjoy the feel of a blade cutting well and under their control. Some do this sort of work on a scroll saw. I've done it that way, for some reason it just irritates me to use a scroll saw. Don't ask why, I don't know. Doesn't matter if it's a low end Dremel scroll saw or a high end Hegner, they just irritate me. I love using tiny files and stones to get something just right, but not for hours.

There are two different things going on in this thread though:

1) Is CNC useful for model engineering. Doesn't matter if you're running CNC on a small benchtop or a Boss3 or a Haas VM3, is CNC appropriate in the first place? For making model engineering sorts of projects from casting kits or those happy with barstock sorts of engines, the answer is likely no. Unless you just like redrawing plans in a CAD package and playing with CNC. But I would say that for most model engineering folks CNC is a sort of neat special tool that for those so inclined adds capabilities to the shop. I would never claim it is a necessity. As a sub part to this, it's really hard to just say CNC. If you make lots of model artillery, you might have a manual mill but a CNC lathe. If you build old style Man Of War ships with 84 cannons you might lust for a CNC lathe. Model rail folks might do better with CNC in the plastic side of the world, be it FDM, resin, or both. I like to cut out model boat, plane, and structure parts using a laser. A engine sitting naked may be interesting, in some context such as running a scale thresher or saw it might be more interesting. The window dressing might benefit from some form of CNC, even if it's just cutting out thin stock on one of the flat bed cutters sold in the fabric and scrap booking stores. They do work well for cutting gaskets!

If I were inclined to build some of the very complex engine projects seen on this site, I'd be looking really hard at doing a lot of it using CNC. Making a radial engine I'd want every part that should be interchangeable to be so. CNC doesn't guarantee this, but it makes it a lot easier to get there. Making something once is nice, getting the dimensions dead on is satisfying. Doing that 9 or 18 times close to perfectly for a radial engine is fairly demanding. I like to stack the odds in my favor whenever possible.

2) Small machines. The old anything smaller than X is a toy. If you restore vintage aircraft, odds are most machines are toys and everyone's shop is too darn small. If you restore watches, a Bridgeport isn't of much use. I use my SB10 less often than I use my Sherline and Taig manual lathes. Not because the SB isn't in very good shape and nicely tooled up, but because my interests lead me into doing stuff that requires a headband magnifier in some cases. I like small projects. Not necessarily easy ones, but physically small. It's nice to pick up a project with at most two hands, rather than having to use the chain hoist on the overhead rails. I can't feel what's happening with a 0.25 mm cutter on my larger mills, unlike on the Sherline mill. Saying any machine smaller than X is a toy is like saying any vehicle smaller than an F350 is a toy. Not everyone pulls 10K lb trailers or is 6'5" tall. Some folks find Fiestas and Scions just fine for their needs, some folks haul heavy stuff and livestock in hard conditions.

Are Taig or Sherline manual or CNC machines perfect? Heck no, they are OK to darn good and surprisingly capable within a certain price and size range. As Warren Buffet says, price is what you pay, value is what you get. I can't afford a Kern 5 axis CNC mill or a Tornos Swiss Lathe. I'm probably not smart enough to figure out tooling a Swiss lathe anyway, and it can take a day to set one up so you better need a lot of whatever the part is. But for a million bucks, they will let you do Sherline and Taig scale parts in a very flashy way! PocketNC would be interesting if I started building really complex stuff though, expensive (ish) at $6500 but not insanely priced and 5 axis, but for small parts only. For my interests, it would be a better fit than a Tormach 440.

If you enjoy putting an older machine back in good running order, particularly the oddities of older CNC machines, that's great. I know guys who have spent a year getting old Matsura, Puma, and Haas stuff back into good condition and working well, Good for them, not for me thank you. I've played that game in the manual machine world, and in the benchtop cnc world (EMCO small lathes), just not something that fills me with joy at this point in my life.

Oh Well, lot of different ways to get from point A to point B eh?

Cheers,
Stan

 

[Richard Hed]

Dunno about that "most auctions do not require a fee to register".

Likely no fee to register but if you want to bid then that's when all the requirements hit.
It was the requirement for large $$$$ deposits when I was looking at perhaps a few hundred $$ worth of tooling that totally turned me off!

Not a fee to register - - - they want you to register so they can bomb you with more auction bulletins - - - - they are quire hard to stop as well.
Somehow the unsubscribe works for a bit and then somehow - - - one is getting bulletins again.

My essay into this world really left a bad taste in my mouth.
I had bought auction stuff before but haven't even looked much since all this 'garbage'.
The auctions seemed mostly to be very large companies trying to unload a mothballed facility quickly with the auction companies (and their friends) trying to maximize their own results assuming that the scrap man was going to be their predominant customer.
Was a pity - - there were a few pallets worth of tooling that I would have liked to have gotten!

That certainly happens, however, that fee is not actually a usual phenomenon. Most auctions do not require a fee to bid. I was surprized a few years ago when one wanted me to put up 300$--the *^#&@% (not a very nice word) actually TOOK the $$ out of my bank without asking me. I put a quick stop to that and didn't bid with them. I learnt too, not to bid on anything where the auctioneers want a fee up front to bid. And I thimpfks there was one who tried to get a lot more before I could bid--I just lafft at those @@*^&)$%! I thimpfk you are wrong about the auctions, however, in general. The BIG problem is to not bid so much that when the tax plus auctioneers fee (18%) and then shipping is all added up, that you didn't pay more than is reasonable for a usually used object (there is a LOT of stuff that is not used also>) . Another problem is getting to see the things yuou are bidding on with your own eyes and if you can't see it, is the auctioneer's discription adequate? Usually their description is very uinder done so you have to go off the photos.

I have bid on rusty chucks--rusty because they just sat on a shelf and were rarely use, thus actually in very good shape except for the surface which does not really matter, and many other things that didn't look at first sight as good stuff. Thing is, I have to bid very low as even if I managed to get a rusty chuck, the shipping qwould kill me for the weight. If I lived within 200 maybe 300 miles of Detroit, or Cincinati or any other city in rust belt, I would have easily stocked my tool room years ago. That's all because with all the other conditions (tax and auctioneer's fee), I could have saved a bundle in shipping which often costs more than the item itself.

It's up to the individual to go on to those auctions or not but I am seeing good deals on large items every week, mills and lathes, welders, other stuff of course, but because I live so far away, it would at least double the price to ship it--NOT a good deal. What is so odd is that last year I bought a TIG welder--free shipping. Grizzly charges for shipping, but it's acutally quite reasonable for large items, in the 2-400$ region. But that is not the case for auctions. Auctions are a big business in which riggers are making a lot of over the top money for simple packaging and sending by fed-ex or whomeer.

 

[Richard Hed]

If I lived close to this auction, i would certainly CONSIDER (Not necessarily bid) bidding for this nice little Emco:
https://www.bidspotter.com/en-us/au...0011/lot-23ebc93e-20ba-4907-b549-af410132fb32
But not unless I could get around the shipping cost somehow

 

[Jasonb]

Timo, yes they look similar to my KX-3 which is a Sieg made and branded one, the yellow on yours suggests it may have been a very early Syil. The one in the last photo seems to be missing the control/driver enclosure

Hard to say if they are all inaccurate base don your old and by the looks of it well used second hand example. When I first got this I did a few test cuts while it was still on the pallet and got between 0.01 to 0.02mm which could be put down to the cutter cutting a little undersize just as much as it could to any inaccuracies in the machine. Not really felt the need to run similar tests since but it is more dialled in nor so I would say 0.01mm or better which does for the engines I have shown, though we may all have different needs.

You mention not being able to get round holes, is this not a problem whatever you pay for a machine as most of the tooling makers have in their ranges "finish boring heads" Which I have seen being used on machines costing 100s of thousands of dollars. Typically a hole is roughed out with an insert drill, then taken close to size with adaptive or similar cuts and finally the tool changer loads the required "finish boring head" which takes the final skim on holes that need to be accurate and round.

Now I can't justify having a set of those or spending the time dialing each one in for a specific diameter and tolerance. However for something like a steam engine cylinder or IC engine crankcase I will bore that on the lathe and then if the CNC is the most suitable tool transfer to that to shape the outside. I bet my CNC'd external faces are a lot more accurate than what would have been sand cast on what I'm trying to replicate.

Though it's just as at home doing bolt hole PCDs where the two parts will go together in any combination of positions and other jobs like that and is as accurate or more so than the manual machines

I tend to cut everything dry except aluminium which up until recently I just brush applied Paraffin to but now have a fog buster type arrangement so very little coolant to worry about.

Your mill is lacking the "trough" that can be seen on mine and the other images of this machine. I find that very effective at catching swarf, only when working on something tall or if using large diameter cutters (25mm or over) that a bit more gets thrown about. In all cases it's far less than the average manual machine will throw out as they seldom have any means of containing chips

 

[timo_gross]

Greetings,

Obviously CNC is not a requirement for making any of the classic model engineering projects.....

If you enjoy putting an older machine back in good running order, particularly the oddities of older CNC machines, that's great. I know guys who have spent a year getting old Matsura, Puma, and Haas stuff back into good condition and working well, Good for them, not for me thank you. I've played that game in the manual machine world, and in the benchtop cnc world (EMCO small lathes), just not something that fills me with joy at this point in my life.

Oh Well, lot of different ways to get from point A to point B eh?

Cheers,
Stan

Very long post, and worth reading.

Timo, yes they look similar to my KX-3 which is a Sieg made and branded one, the yellow on yours suggests it may have been a very early Syil. The one in the last photo seems to be missing the control/driver enclosure

Hard to say if they are all inaccurate base don your old and by the looks of it well used second hand example. When I first got this I did a few test cuts while it was still on the pallet and got between 0.01 to 0.02mm which could be put down to the cutter cutting a little undersize just as much as it could to any inaccuracies in the machine. Not really felt the need to run similar tests since but it is more dialled in nor so I would say 0.01mm or better which does for the engines I have shown, though we may all have different needs.

You mention not being able to get round holes, is this not a problem whatever you pay for a machine as most of the tooling makers have in their ranges "finish boring heads" Which I have seen being used on machines costing 100s of thousands of dollars. Typically a hole is roughed out with an insert drill, then taken close to size with adaptive or similar cuts and finally the tool changer loads the required "finish boring head" which takes the final skim on holes that need to be accurate and round.

Now I can't justify having a set of those or spending the time dialing each one in for a specific diameter and tolerance. However for something like a steam engine cylinder or IC engine crankcase I will bore that on the lathe and then if the CNC is the most suitable tool transfer to that to shape the outside. I bet my CNC'd external faces are a lot more accurate than what would have been sand cast on what I'm trying to replicate.

Though it's just as at home doing bolt hole PCDs where the two parts will go together in any combination of positions and other jobs like that and is as accurate or more so than the manual machines

I tend to cut everything dry except aluminium which up until recently I just brush applied Paraffin to but now have a fog buster type arrangement so very little coolant to worry about.

Your mill is lacking the "trough" that can be seen on mine and the other images of this machine. I find that very effective at catching swarf, only when working on something tall or if using large diameter cutters (25mm or over) that a bit more gets thrown about. In all cases it's far less than the average manual machine will throw out as they seldom have any means of containing chips

Hello,

I hope that side track about the machine is interesting not only for me.... happy about the reply.

The example for the round holes was exaclty my point. Not that you need the super top notch high end machine, but a certain Z-travel can save the day.
Finish boring heads need something between 3" and 5" of height, low rpm and some torque.
That is why a finish boring head is not an option for router style machines. Fixed 20 000 rpm, ER11 collet chuck, 2" of z-travel and a wobbly z-axis?
.... But not all is lost .... there might be a lathe to do the occasional "round hole" Face plate, four jaw chuck "between centers boring bar"?
Most of the other holes are fine anyway, or you do not make precison holes with the cnc then it does not matter anyway.

I would say for the average metal part a column style machine with z-travel wins over the router, because it is that much more flexible with the set ups and a lot of conventional accessories can be used.


Greetings Timo

 

[Richard Hed]

The "Toys" can also be used for pattern making which the gantry type macjines would be well suited to but even the benchtop mill ones like mine can make usable patterns, a few examples of what they are capable of below

iF I had no choice but a "toy", I would take it gladly . . . however . . .

 

[Bazzer]

KQuiggle,
perhaps you're asking the wrong questions, the questions you might be asking are
is anyone making actual model engine parts with a toy (Sherline,Taig,etc) CNC mill ?
I suspect you'll find the answer to be effectively zero (except for ClickSpring, but
he's the exception that proves the rule, none of us mortals can do what he does
with or without CNC)
of the (few!) people that actually use CNC for model engine parts what do they use ?
I suspect you'll find the answer to be effectively nothing smaller than a Tormach, or Bridgeport clone/conversion and typically much larger like old Haas, etc

if all you want to do is learn CNC then start with (free for us hobbyists!!!) Fusion-360 as the CAD side is a steep learning curve no matter what iron you end up with.

if you get a toy CNC all you might really be learning is the limitations and workarounds for it, which probably won't be relevant to the real machine you might eventually end up with with different controller and different iron.

finally be realistic about what you're going to do with it, I've been building model engines for 30 years now and still don't see how I'd use CNC effectively. I don't think CAD is useful unless you want to machine from bar-stock something that looks like a casting with all its curves, fillets, mounting bosses, etc. and I don't think CNC is useful unless you're going to be making multiple copies of the part.


BUT, if you enjoy discussing options on forums then you're AOK, and if you can't afford the big iron and just want to get your feet wet with a toy you're AOK, its a hobby and what ever turns your crankshaft is AOK !!!

Peter.

Peter

I have to agree with Jason on your appraisal of 'toy' CNC machines. There are some superb parts for small engines being made on even Sherline and Taig machines. On a slightly different point, Sherline even use their own machines for certain single operations in making the machines in their factory, I have seen this during a factory tour.

Jason showed examples of how CAD and CNC can assist in making hobby engines, IMO CAD and CNC bring another skill set to model engineering that are neither essential nor replace traditional skills and machines but rather compliment them.

There are some superb pieces of model engines being made on these small machines.

Take a look below and tell me that people are not making real running engine parts on small hobby style machines, don't get fooled into thinking the machines in the photo's are big, they are smaller than the machines that Jason is using.

If you know what you are doing you can even make a very good living off of working hobby CNC machines, I know as I do that with a what a lot of people would call a hobby CNC gantry router.