Is OneCNC what I want?

[mnagel200]

Hi, let me first start out saying that I really have no experience in CAD/CAM software at all. But, I'm very interested in parts design and have a lot of ideas that I would like to someday realize. So, I am looking to get into some sort of CAD/CAM software. Here's what I want to be able to do: I want to be able to design my ideas completely by myself and then be able to send a disk with the design to a CNC shop to have the designs rendered. I want it to be as seamless as possible. I don't want for the CNC shop to have to do a whole bunch of other work on the designs in order for it to be done on his mill thereby costing me more money. That's one of my biggest perogatives: being able to do as much of the work (save the actual milling, since I don't have the money to invest in CNC mills) as I can to save money. Does this sound realistic? Is OneCNC what I'm looking for? Is there other programs out there that could do this? Thanks!

Mike

[HuFlungDung]

You should most likely focus on learning how to model or do the cad work correctly. That is really the end of your duty as a buyer, because the shop you hire must and will use their own savvy to produce and program the part as they see fit. Considering your inexperience, it will not do you much good to produce machining processes that are not suitable for use in the real world.

Now OneCNC can give you some insight into the complexities of programming and you will appreciate what must be done to produce the part. But without hands on experience of programming and then cutting it yourself, you just will not learn enough.

But to get your feet wet with solid modelling in cad, if I were you I would check out some of the student versions of the popular cadcam systems. Maybe Solidworks (because it is very popular in industry and is cool to boot), or Rhino, just to name a couple of popular chocies. OneCNC also has a Solid creator version available without any CAM, but I don't think there is a student version.

[mnagel200]

Thanks for the insight! So, judging by your experience, I should concentrait on Solid Modelling in CAD. That sounds reasonable enough. So, if I learned Solidworks or Rhino, would I be able to send my designs to a CNC machinist and have them milled? And also regarding the student versions of these programs, what makes them student versions? Can I do everything I could with the regular versions? Or are they simplified versions? How about Alibre? I was looking into this program before I found out about OneCNC. Would this be an suitable program to learn solid modeling? Thank!

Mike

[HuFlungDung]

Yes, Alibre is another popular one.

The student versions of some software are available to students (usually with proof of attendance required) at a reduced price. I am not sure of crippling, but I think a lot of them work just like the full versions. Their angle is to 'hook you' as a student in hopes of selling a full version at some point later on

A good solid model serves as an excellent basis to have your job understood and quoted accurately. Still, there are certain principles of design required even if your model is perfect, that will have a great effect on the pricing.

Things to consider:
-Learn about tooling, primarily endmills. Learn what is considered to be standard lengths which can commonly be applied to a job without getting into using 'extra long' lengths which are much more difficult to use in practise, and which can only be used at a reduced metal removal rate. The machines used to do the cutting, cut by the hour, not by the cubic inch, so you get less value for your design dollar by having to use long flimsy tooling to cut it.

This consideration will affect how small the radii and internal corner fillets will be in your designed parts. Deep pockets should be designed with large fillet radii so that the tools used to cut it can be as beefy as possible.

Learn how there are different metal removal rates for small versus larger tooling. Always use large radii when possible, and avoid small sharp internal corners.

Design any pockets with radii that are slightly larger than standard endmill diameters. For example, a 1/8" internal corner radius might seem like a good match for a 1/4" diameter endmill, but it is actually not. Tools tend to squeal when they engage a full corner radius while they change direction. So, your design radius will likely result in the machinist having to use a 7/32 endmill, just so that there is a tiny arc to be swept through the corner, which will cut nice and clean. Because he has to drop one size in the tool, then the risk of tool deflection and its lack of rigidity will compromise the metal removal rate. He will not phone you to ask you if you can redesign your part with a slightly larger radius, he will just obediently follow the model, no matter what the extra cost, which will also apply. But, you, if only you had known, could have easily opted to add .015" to the design radius without any harm whatsoever.

Learn about endmills (called bullnose mills) with preground corner radii (or radiused insert cutters), and design your part pockets with bottom fillets that match what is commonly available. If the pocket corners are deep, don't use spherical fillets in the bottom corners if possible, because a ball mill will have to be used (an extra operation) to clean out the corners. In many cases, a large fillet in the vertical corner will work just fine (the outside radius of the tool creates this as noted above), and a small fillet radius swept around the bottom of the pocket corner will match the radius corner ground on the tool. Fast and simple to machine, but quite often, this type of oversight by the designer can easily double the cost of machining a part that would be equally serviceable. When the designer just pulls fillet specs semi-randomly 'out of the air' that take no consideration of the tooling into account, somebody has got to pay

[DareBee]

Hu
It is posts like this ^ that make you the KING. I would be thinking all these things but usually just wont take the time to type it at my 25 word/min 4 finger pecking.
Everything Hu said is dead-on.
VERY few designers make machinist friendly parts, Either they pay through the nose for what they want or they pay me to redesign the part - in SolidWorks I might add :-)

[Geof]

I will add a hear, hear. I think designers should be forced to spend a few years making things before being allowed to design anything.

But then if they all followed Hu's advice there wouldn't be as much work for Darebee.

[HuFlungDung]

Should I expose our secrets even more? Or are you guys willing to fork over the 'secrets protection' payola I asked for?

[Dan B]

The student version of Rhino is identical to the commercial version. You just have to provide proof that you are a student to get this discount. Buy it as a student and it is yours forever. Once you are done school, you can use it to make money.

Dan

[angelballer]

Solidworks' student version prevents designs from being used in production work so it isn't the full version.

Josh

[Dan B]

I hope this isn't considered a hijack of this thread, but since the topic had to do with oneCnc, I'm going to throw it out there anyway.

Are there any "shoot-outs' published between OneCnc and some of their competitors? By "shoot-outs" I mean feature comparisions and real world applications. I would be extremely interested in reading what WorkNC users have to say about OneCnc. Are they in the same league, or am I comparing apples to oranges.

Thanks

Dan

[clarry]

We have Worknc Mastercam and Onecnc. I dont use Worknc myself we basically only use it for the 5 axis by one guy but he uses Onecnc as well in preference. Modeling in Onecnc is far better. We used to use Worknc for 4 axis too but now we use Onecnc for the 4 axis parts because their full 4 axis is very good and much easier to use and see. Overall we prefer to use the Onecnc and never use MC anymore. Onecnc is certainly in the same league maybe appears less things but that is mostly because it has more automatic ability. The thing we like about Onecnc is its ability is solid and reliable very good functionality verification preview and so on. I doubt you could make a feature list because they are different in many ways. It appeals to anyone that comes from the shop floor to programing because it makes life easy is the easyiest way for us to report.

[Dan B]

Hi Clarry,

Does your shop program continuous 5-axis with WorkNC? or Positional?


Dan