CNC files

[John S]

Brief Intro then cut to the chase.

Over the past couple of years I have been involved with CNC mill conversions, mainly based on the Sieg X3. Recently I have been working closely with Sieg themselves to offer a turnkey CNC milling machine as a plug and play exercise and recently it's starting to come to fruition, at least in the UK and the the US should follow shortly.

This is not an advertising stroke and that's as far as the intro is going.

Now the chase.

Because we drag these things to shows we like to show them working making parts relative to model engineering.
One such example is a loco wheel and a con rod from a generic IC engine.

These get a lot of interest at shows, that much that a software company, Vectric, who make a nice CAM package have adopted both these items as samples for their 2-1/2D software.
See Cut 2D at http://www.vectric.com

Sorry if this sounds like an advert but it's only trying to put flesh on the bones.

I can see the time when designs be it IC, steam etc will be exchanged / sold as G code file for CNC machines to make. Possibly buy a kit containing all the castings, bar material , plans and code on CD.

What I'd like to know is do others share this view and is there a free design out there that will lend itself to being done by a beginner to CNC ?
If so then I'm willing to code all this up and make the first one as an exercise for what can be done by CNC.

This will then be made available for anyone to copy free of any charges.

Idea's, flames, bricks thru front windows ??

John s.

 

[AllThumbs]

I have heard of this type of thing before. On another site regarding model airplanes, not model engines. One problem I forsee is that not all machines run all gcodes the same. Since most of the parts will be one offs, parts will be ruined along the way, not to mention the possibility of machine damage and/or personal injury. Add to this that you are talking about offering this to beginners, which would compound the problem.

Eric

 

[Cedge]

John
Neither bricks nor flames. CNC is getting cheaper, although it remains somewhat prohibitive for the poor hobbyist like me...(grin). The idea has merit for those who are into the CNC end of the craft, but my personal take is that it would soon become akin to watching paint dry. Once the code is loaded, an odd tool change and the occasional metal swap wouldn't excite me all that much. No denigration is meant by my comments... I just enjoy the primitive part of turning dials, marking out and measuring that manual machines offer.

Your idea is a pretty logical next step to what Liney engines is doing these days. They supply drawings for little money or they can ship a kit with precut metal, drawings and instructions, for several engines. They seem to be doing rather well with them. I can see it working for at least some of the CNC crowd as well.

I am investigating the possibility of getting into some CNC, down the road. A friend is holding a couple of bench top CNC mills that are quite tempting.

Steve

 

[Mcgyver]

Hi John,

the next step in the evolution is just ship the completed engine ;D

If I dissected where the fun is in model engineering, Id say it's in the solving the puzzle...the puzzle of sequence of operations and reference surfaces and set ups to make a part. There's a sense of accomplishment in this. imo this is why it is as fun for the more experienced practitioner as it is the beginner. Remove or diminish this and i wonder if a lot of the intrigue is removed as well. Not saying that's whats happening with your idea, but at some point, codification takes the fun away, taken to the extreme it would like putting together a plastic model

at the same time I can see how cnc changes the way parts are made. Your example of making a driving wheel pre-cnc was a complex machining task, enough so that mostly castings were bought. Still, if I'm buying a cnc mill and loading a program, its not like I've accomplished much or solve a puzzle, I might as well just buy the wheel.

The other challenge is it would have to be one heck of a set of digital instructions to accurately replicate the driver with the correct taper and profile to each spoke etc. My sense is that whether its machine tools or cameras, unless you are working with quite high end stuff, digital is often the poor sister to analogue in representing the real world. Maybe this is where the opportunity lies, given the price of castings. I have no interest in a cnc engine project carved out plate that is going to look hokey compared to a simple analogue engine, like say a Stuart 7a. However, couldn't the cnc programs be advanced to the point that they'd carve out of a chuck of darabar parts for similar engine that held even finer detail and correct form than the 7a castings....Surpass what we have and, well, it becomes highly desirable.

I pine for a cnc. I'm 80-90% through making a simple cnc including the electronics. I do think however that the more one's work is one ofs, the less value it has and the more its role is as a specialized tool augmenting manual machines. That is partially because of the added burden of cad cam to produce a cnc part, but also because we are unlikely to end up with cnc that can compete with our older iron it terms of hp and rigidity - .

I've gotten got a kick out of making the cnc and trying to learn the electronics and think it will be just great for things like circuit board routing, odd shaped parts like oval flanges and reversing gear brackets etc . What I've made (the mechanical part) is a bit of a joke, really just some slap together mechanics to see if i can do the electronics - I may ultimately purchase the type you are talking about. I see either cnc (my diy or bought) as being a fantastic augmentation to the shop.

 

[SmoggyTurnip]

Rather than having files for making engines, why not have files for making tools. Not everyone who has a cnc machine will want to make engines but everyone needs to make tools, jigs, etc.

 

[BobWarfield]

Turnip, you bet, Tools and all kinds of things will be popular. This is the model of the future. CNC often requires fixtures that are a bit different too, such as soft vise jaws so you can flip parts to machine both sides. The g-codes can include any purpose-built tooling along those lines. Also, many types of things just aren't that much fun once you've done it, or may not be possible at all without CNC. I've made an indexable dovetail cutter. It was fun, and I'm glad I did it manually. If I wanted to make a slightly different one, I'm not sure I'd be that much more stimulated versus just firing up the g-codes the next time around. Or, consider a clamp I designed for CNC:

These would be a real pain without CNC. Especially if you wanted a set of 4 for the mill, and 4 extras for the drill press or whatever.

CNC is here and much bigger than people realize. CNCZone is by far the biggest of the hobby boards whether you like going there or not, and it produces very cool results. Zuesrekning is using CNC on our Team Build and getting great results, so it's even here on this board.

There is a tendency to dismiss CNC as taking all the fun out. You might as well ship the finished engine, sez McGyver.

Well, some of the puzzle is gone, but so is some of the drudgery. If you're going to CNC castings, you will need to have some pretty precise setup skills. The more complex the engine, the more careful setup work will be called for. It isn't just slap a block of stock in and hit the button. Additionally, the majority of folks do not have a full range of CNC. Most have just a mill, for example, and must still manually do all turning. Most will not have a 4th axis if the job calls for that. Or, use the CNC to make the masters out of wood for a mold the way Wes does and then do some casting.

I'd say go for it, John. Makes total sense.

Best,

BW

 

[Cedge]

Bob
Easy now...LOL. No one is putting CNC out to pasture here. Most of us are not in the position to invest that kind of money yet. Let the prices drop a bit and a lot of us would go there. I enjoy the challenge of manual machining and yes... I often envy the capability of CNC operations. I suspect many of us do. Truth being told, its nice to have CNC members that we can steal ideas from...(evil grin)

I love to pop in on the CNC boards sometimes to see what they've been doing, but I have nothing to contribute but eyeballs and a bit of keyboard drool. I've spent hours on your site enjoying your efforts and your style of sharing the information. Hell... I'd ask questions, if I knew what questions to ask. I'd have to know what it is I don't know that I don't yet know to even ask them.

We sometimes forget that Baskin Robbins is a successful ice cream retailer BECAUSE they offer 31 flavors..... at least one to appeal to every taste that walks in the door. There are just some flavors we ain't tasted yet.

Steve

 

[Mcgyver]

You might as well ship the finished engine, sez McGyver.

No i didn't say that. Please don't quote me incorrectly or take remarks out of context. I said the next step in the evolution is that and smiley clearly indicated the remark was to be taken tongue and cheek and was a bit sarcastic. I went on the say how and why cnc interests me. I have built a cnc, ground up, and am 90% there and in trials - you don't do that unless you have a serious interest and think its both fun and holds a lot of promise. I suggest maybe before you cast aspersions like i think cnc takes all the fun out of it you more carefully read what i wrote. Besides, why waste time tyring paraphrase what you think i think?

There is a tendency to dismiss CNC as taking all the fun out

where did you observe this tendency? That hasn't been my experience, I see a huge interest in cnc from the hobby sector. Including me.

I also push back on some of your comments about what is required on set ups for complex engines and/or castings - you know this how? I've done lots of both, while I lack the depth of experience with cnc that I have with manual machines I don't think it much matters cnc or manual - the challenge with say castings is creating datum surfaces that can both be measured form and clamped to without distorting the part....anyway i think the set up challenges are more relative to the part not whether its cnc or manual.

 

[Bogstandard]

I have been having a bit of a discussion about available CNC millers with Cedge.

I know absolutely naff all about CNC, other than some keyboard work is done, a lump of whatever is clamped to a table, a button is pressed and 10 to 15 mins later, or even less, a part that would take me all day to make manually, would be ready to be used. You might class me as a bit of a moron not knowing about such things, but I am sure what I have just said applies to the majority of people that use this site.

The reason I am starting to get interested in it, is not because I want to, it is because of the speed it can hack out the bits that I need, repeatedly.

This is because I don't have enough hours in the day to produce all that is required of me. There is nothing really that cannot be made manually in what we do, it is the time issue and repeatability is the main plus point of CNC.

I will still carry on making engines the 'hard' way, it is that side that gives me the enjoyment I crave. But when it comes to my other commitments, I am forced to look the CNC way, and I am actively seeking a miller that will suit my needs. Just waiting for a well proven, reasonably sized and priced one to come onto the market. Then it will be a massive learning curve for me to climb to get the bits made.
Then maybe I will be able to talk with the ones in the 'know', without being baffled by all the jargon.

John

 

[BobWarfield]

McGyver, you deal in curious shades of meaning. I'll stand by exactly what I said.

I look at these forums as a conversation. If these posts had played out as a conversation around beers, John would say what he said, you'd say what you said, I'd say what I said, and suddenly you're up out of your chair, voice raised. It makes no sense to me for you to do that given this conversation. If you want to clarify your position, by all means do so. Where's the point in attacking or getting upset?

And why would you waste time trying to paraphrase what you think I've said if you don't want me to paraphrase you (see how silly this all sounds?), or attack whether I have a clue how to set up castings for CNC?

As for the castings, I've simply pointed out that g-codes or no, you're still going to have to have some setup skills to get it to work. How do I know this? First, because I've seen it done. Second, because there's castings all around us on this site. I was looking at Hilmar's posts, for example, and imagining how I would deal with his Stuart on CNC machines. As for the topic in general, this setup issue is relevant. There's more to CNC machine work than g-code, and it isn't equivalent to getting a finished model nor even to assembling a plastic model. If you do or don't want to do CNC, more power to ya, it's all fun.

Calm down fella, quit looking for a fight. There isn't one here to be had and it isn't in the spirit the board wants to work on if there was.

Life and conversations are a lot happier if you assume (rightly in this case) that the whole world actually likes you!

Cheers,

BW

PS I'll buy the next round of beer! ;D

 

[shred]

I have a little CNC mill. It works pretty well, but it's far from "load up some stock, push start and walk away" like the big machines are. Without an automatic toolchanger, you're limited to what you can do before a toolchange, and without a 4th axis, you're limited to one setup.

On single parts I don't think it really saves any time over a good DRO-- I spend a while thinking about how to hold the raw stock and how to cut it, then drawing up each of the cut steps on the computer, then converting that to G-code, then going out to the shop, squaring up a block, proofing the first program cutting air, then running the first program, changing the bit or the setup, proofing the second step program, running the second program, etc, etc ...

Then I usually end up watching the little robot make parts anyway, because it's cool (or I'm worried about something going wrong), so it's not like it even frees up much of my time

For multiple parts or complex curves, it's absolutely great-- the fan blades on my mini-fan were a perfect example-- I got a copy of the 1890's patent, traced around the blade shape, pulled that into the CAM software and made G-code. Then it was only a matter of sticking a plate of brass to a sacrificial board and hitting 'go'.

Thing is though, I couldn't take that G-code up to my friend's place and have him run it without lot of tweaking-- where I think machine zero is isn't where his is, the tools he's got are different, his axes are setup different, etc.. and that's only a simple 2D part. There needs to be a lot more work in portability before G-code sales make much sense. CAD drawings, maybe, but then there's still a number of steps to go through.

 

[firebird]

Hi

We all know that we need to encourage more youngsters into our hobby. It seems to me ( I have the experience of 3 kids) that they seem to lack the patience to make something by hand or by hand operated machines. What they are good at is playing on computers. If they can sit there and design something on the screen of a computer that is a skill in itself and something I doubt I could do. If they could as you say bolt a lump of metal to a mill and push a button and let the computer programme make it for them then so be it. I think thats the way it will go. As time goes on CNC machines will become cheaper and one day maybe find itself in my workshop. If complicated parts can be machined from a solid instead of the usual sometimes expensive casting then more complicated models that I probably wouldn't attempt or be able to afford would become a realistic proposition especially if some kind soul wrote the programme for me and posted it on forums like this free and for all to use. I say go for it John.

Cheers

 

[John S]

May I make a few more points without appearing to be standing on a soapbox ?
In fact I don't actually sell anything to the general public.
Most of my work is done at development level for companies.

Firstly CNC is now affordable, OK I know for some it's not but in relation it is there and getting there faster everyday.
My big 3 tonne CNC cost about £34,000 when new, and no i didn't pay that. Of this £34,000 possibly £10,000 was earmarked by the controller. This controller could be replaced tomorrow by a $159 licensed download. The drivers which cost £800 each to buy and £125 just to test when they go pear shaped have been replaced by modern £70 units that are streets in front of the old units.

CNC is also getting more acceptable as the flat earth society guys are dying off and the creeping Jesus guys are being shouted down. Bob has mentioned CNC zone, not a nice place to visit but it's a victim of it's own success. If there was no interest it would have faded into obscurity.
Go to You Tube and do a search on CNC, last time I did this there were 12,000 videos. OK so some are commercial and posted by the likes of Haas etc but the bulk are home shop guys either converting a lathe or mill or even building a router type machine from MDF, draw slides and all thread.
Don't laugh they work and more to the point they work enough to make the MKII. In fact for some CNC has become their hobby but we don't want to go that route.

Bogstandard brought a good point up when he mentions time and CNC as a means.
I must admit I'm not into building models, I spend a lot of time building special tooling and jigs etc and like models some of it is interesting and some is just boring. 8 widgets, all the same needed for the same job. OK let the CNC do those whilst I get stuck in to that nice interesting setup.

In the UK in the 60's and 70's our intrepid Muddle Engineer would have his tea and disappear into his shed / workshop every night and probably some of the weekend. Try doing that nowadays. Her indoors would soon have something to say. CNC can help here. You spend two nights INDOORS doing your programs on the computer then you get to run those on shed nights, perfect and in a 1/4 of the time it would take normally.

So your two shed nights are now four because if you are indoors you can't be accused of being outdoors can you ? :

My concern is what do people do when they have unpacked or built their new machine, had a play and made it run up and down the table a few times.

It would be nice to have access to a CD with files on it pre-done so they can bolt a bit of scrap on the bed and go to it as part of the learning curve.

Allthumbs mentioned that many machines don't run G code the same but I was thinking of Mach3 as the controller which by price alone with probably be the controller of choice.
The G Code this machine uses is very generic, in fact my big old CNC can read this with only one line change for tool offset being needed.

What would be needed is a way to edit the published code for feeds and speeds depending on what machine runs it.
This is easy to do in a simple editor like Notepad and the G Code is only a text file, after a time sad people like myself can actually read this and know where the tool is going to go, yes sad isn't it 8)

Some while ago I drew a Harley Davidson badge up and coded it for a friend. I have lost count of the number of times I have been emailed for that file and it was never advertised or offered for sale.

Bogstandard, Try to make it to the Harrogate show on the 9th, 10th and 11th of May, I can promise you some interesting things.

Firebird. Agreed, kids today are wizz's on the computer. My son drives Solid Edge for a living designing heat exchangers. He's jsut done an enclosure for a mill that opens up and warns if somthing clouts something else.
I can't do that but having said that I know a retired guy in a home who 'building ' a full sized Fowler plowing engine on the computer because he has no workshop.
Great guy and the last time I saw him he told me he hasn't broke one tool yet ;D

 

[Cedge]

John
Your retired friend and I would have fun together. I modeled the Minnie in 3D using ray tracing software, a couple of years ago. Over 3000 parts and almost 400 animation paths to were used to make it run. Then I discovered that my computer was too light to render the animation sequence, once it was all done...LOL. I still have the files and am looking to buying a stronger computer soon. These days big memory comes cheap.

Here is a stationary rendering of the project.
Steve

 

[AllThumbs]

I have a converted mill. I love it. It doesn't take any fun out, nor does it remove the challenge. It's very challenging to get the part right the first time, everytime. It still takes skill in that the operations need to be made in the right sequence, the part must be clamped in often imaginative ways. Plus you can make some very cool parts.

Eric

 

[John S]

Not geometrically correct in that the cutter was only a vee cutter but still interesting from the simple setup required.

[ame]http://uk.youtube.com/watch?v=FkzqwIjjBhs[/ame]

Another variation on the same theme.

[ame]http://uk.youtube.com/watch?v=fps0OR1eF_s[/ame]

Ignore the shaking about, the machine was on a transport stand ready to go to a show.

 

[zeusrekning]

I'll put what input I have. I think this is another one of those questions without an answer. So I'm speaking from my viewpoint with projects including engines, off road karts and powered equipment. There are a lot of things I can do on our CNC mills that I just can't do on a Bridgeport. And some things that could be done but would just take forever, at least for me. But as far as turning, there really is not much of an advantage(again, for me) and this is assuming just a basic single spindle single turret lathe. Cutting thread is easier, making multiple parts is obviously much easier, and cutting tapers and radii is easier. Back to the mill, If you want to take advantage of a CNC mill you really need a good CAM package. What we use at work is just a simple 2-1/2 axis package. This would not work well for what a lot of us would like to do. I do think software has and is continuing to come down though. If you want to take full advantage of a CNC mill you would want to do 3D milling I think.
I think setups are basically the same for manual versus CNC. The more complex setups on a CNC mill are usually required when doing what would take a couple operations on a manual.

Now to what really interest me. I went to the SouthTec machine tool show a few years back. They had "Touch to Teach" machines. I'm not confident the brand or actual name they were called. But you could run the lathe just like a manual lathe, but say you turned up to a shoulder and needed an external radius (G3) you would type in the radius you wanted and while you moved the carriage, the cross slide would move automatically to cut the radius. , same for tappers. You could also push a button after every move you made and it would store it so you could run the part again, or multiples of , with out writing a program. There are similar conversational machines for milling.

 

[alan2525]

This is my first proper post (excluding the welcome one)

I'd be interested in the idea of a package containing all the cnc files for a project. At the moment I'm using a Roland EGX 300 to cut out model parts, engrave and cut thin brass sheet for the cab of a small loco.

The loco is 16mm:ft and I'm looking to convert a Taig Mill to cnc and work on machining larger parts for the loco too.

One area that mystifies me a little with cnc is the actual machining sequence for a particular part, in manual machining the greatest difficulty is often holding the item in position for the various machining steps. A part by part set of machining instructions to go with the files would be an excellent learning tool.

Would sort of level of cnc knowledge would one need for your idea and also what kind of cnc setup? Small Taig Mill, Micro Mill or large 5 axis setup that can machine Ferrari V12 Engine blocks - like the cnc machine I dream about owning?

 

[Mcgyver]

McGyver, you deal in curious shades of meaning. I'll stand by exactly what I said.

stand by whatever you want, but you said

There is a tendency to dismiss CNC as taking all the fun out. You might as well ship the finished engine, sez McGyver.

that is a misquote and takes my post out of context, anyone reading it who hadn't read post would assume i was somehow anti-cnc. I don't appreciate either the misquote of the repacking to suggest i dismiss it or think it takes all the fun out. It's neither true or what i wrote or curious.

As for the castings, I've simply pointed out that g-codes or no, you're still going to have to have some setup skills to get it to work.

that's a reasonable statement, valid point and i buy it. Your original statement was far more absolute. The point is valid but but the lecturing tone from someone who has done neither was over the top so i called you on it, same as someone would over beers.

For someone in a conversation to declare BS it doesn't have to mean they're angry. I am neither upset, jumping out of my chair or looking for a fight. otoh, to use your beer's analogy, if you were confronted by someone you think is getting hot under the collar telling them to 'calm down fella' is a rather incendiary remark likely to escalate rather than diffuse. Not me though, I'm just not upset

 

[Cedge]

Alright you two... cut it out. Go find separate trees to pee on.

Steve