Gibbs for mouldmakers and fixture builders

[krustykrab]

I was wondering if I can get some unbiased feedback on how Gibbs performs with 3d work like mould making and fixture building....cnc wise.

I am looking into a multitude of cam systems and need some advise from real users, not just salesmen.

Thanks.

[WORKALONE]

Hi Krusty Krab,
I cannot give an unbiased reply about GibbsCAM as I have been using GibbsCAM products since 1988. I can tell you that I build a lot of permanent molds with core boxes, core boxes with cope and drag sections. Some of the molds have a part B/P available, some do not. I digitize where I can. I build the finished casting or finished core in Gibbs and can control the shrinkage ratio according to the material cast. Gibbs has a parting line tool that is a great help. Creating a 3D tool path is easy in Gibbs. I use Fadals and they handle the mass of code with no problem. I cannot compare Gibbs to any other systems as I quit looking in 1988.

[cadman]

Hey Krusty -

All I make are molds, patterns, masters & associated fixtures for the composites and thermoforming industry. 3D tool paths are very easy to create in Gibbs. Also, Gibbs has a big version update, V8.0, in the works that will focus on 3D milling and high speed machining.

[krustykrab]

I had someone over for a demo yesterday and I really liked it. He didn't really push it as a powerful 3d cam ware, but he didn't knock it either.

There was one thing that turned me right off of it however. The toolpaths that are created want to go up to safe z between each and every step over. Is this so, or was I just not shown properly?

Obviously this would present a huge waste of time.

[Gibbsgod]

Here you go, the truth the whole truth and nothing but the truth....


GibbsCAM is a GREAT all around product, it does 2D VERY well and is very flexable. You can make it do just about anything anyway you want. This is importaint because every mold/tool and Die shop I have sold GibbsCAM to have a large amount of 2D work as well.

As for the 3D toolpath. Here are the good and bads:

Good

Very SIMPLE
Fast toolpath calculation
respectful use of associative toolpath
Good Roughing Paths (not a ton of retracts)
Flexable
Can be proficent at it in less than a week
Many more.....

The BAD

Not suited for LARGE Mold work, IP's, Dash Panels, Facia Molds
This is because there are not many "Optimizing" toolpaths. The ones that find and 3D re-Machine the extra material.

Lack of Shallow/Slope Miling
Looping Toolpaths (Lace Cutting)
Skimming Retracts


In all, If you are doing VERY Large, VERY COMPLEX Molds/Dies you should look at a specialized product. The 2 best in the industry are WorkNC and PowerMill. (I have used them both)

If your work fall into slightly smaller work and you need to use Solids for modeling and cutting then GibbsCAM is a Great fit for you.

As some one said before, Gibbs is adding numerous 3D Milling upgrades and additions to the product. (Slated for V8). The stuff that they are talking about will make most if not all the above information useless. GibbsCAM should be close to a one stop shop for all your milling needs.

Your comment about the retracts, I think the operator did something wrong, Most of the Finishing cuts in GibbsCAM stay down very well and retract only if needed. The roughing and Z Level finishing have some retracts but no more than other products do.

Good Luck

GG

[WORKALONE]

Hi Krusty Krab,
The Safe Z retractions are part of a few options to choose while creating a tool path. "No Retraction" is also available.

[Gibbsgod]

This can somtimes be a bad thing. The toolpath can violate the part if this option is not turned one.

You need to know the right part deffinition to make this work without error.

GG

[cadman]

Where you do have Z retracts you have the option to either let the tool FEED back to the part or RAPID to the part at a distance that you set. This can be a big time saver.

[krustykrab]

Sorry guys, but any program that doesn't provide skim moves on retract is a severe time waster.
Especially when you are finishing fixtures to zero stock with smooth finishes.
You can imagine the tens of thousands of retracts involved. This could waste as much as 5 hours or more per job.
I think I will keep looking.
Thanks for yer advice.

[Gibbsgod]

I don't think you understood my comments.

It shouldn't matter when "finishing fixtures to 0 stock with smooth finishes", when finish milling, there should be little on no retracts involved anyway. The only ones would be to re-position to another area.

If retracts would add 5 hours or more to the job, then you need to look into changing the programming or get a faster machine.

Look at the software again, the retract issues should NOT be issues for your finishing.

GG

[krustykrab]

gibbsgod,

If you are programming a linear toolpath on a large sweeping 3d surface with a 1inch ball cutter, the stepover required would be about .3mm to achieve a smooth finish.
If the toolpath is retracting up to safe z between each stepover then that IS a waste of time.
Of course, if you choose to machine using zig-zag, then it wouldn't need to retract. Unfortunately, zig-zag machining doesn't result in a nice looking finish when it comes to metals, it will leave directional change lines.

I will get another look at the software, when the demo disk comes, however, the rep that showed me the software said that the toolpaths retract to safe z between stepovers. Perhaps he's misinformed?

[Gibbsgod]

No, you were not misinformed by who ever showed you the software. In a oneway cut (Box Cycle, climb only etc...) the tool will rapid to the specified Z plane to return for the next stroke.

I have not yest seen a software though, that will skim these kinds of moves. (But I have never looked for thie either) In most cases, the "SKIM" moves are reposition moves to another location on the part for more cutting.

I would like to see a one way cycle with skim moves included. I wonder how much time to would really save, is a straight linier move faster than a move that is following the contour of the part on every cut?


Good Luck

GG