Waterjet cut programming

[glenneaux]

At my work we run a waterjet, and mainly do thing parts on it (chromoly .032" to .125"), and we often try to cut holes to size but being picky seeing as its aircraft stuff we often have problems with the small "gouge" left at at the leadin.

The machine is a Techni machine, and all programming goes through their own software, and its a bit of a pain, especially seeing as leadins etc are all placed by hand. You can however import NC code.

say on .040" material, how are people programming to cut say 1/4" holes? Straight lead in, curved ?? What about the feedrates, i know our machine speeds up and slows down etc as it moves into radii/straights.

The goal is to program it in mastercam with parameters for such things so its more defined and standardized - and then nested - the machine provided nesting functions suck!

[H2Oknife]

This is my first post here on CNC Zone and I came across your post. I'm looking for similar info as you. Not sure how your doing with Mastercam for programming. I'm in a similar situation with a Techni waterjet. Very unhappy with their software, doing manual leadin/out and nest is really bad alone with about everything else. No better luck with cut quality either. Mfg's answer is to slow it down but now we lost our competitive advantage and still can't cut a round hole. We are really struggling to making good parts. Have over 12 years experience with a different brand waterjet so this turned into a real setback to say the least.

[glenneaux]

Hey mate

Glad to hear I'm not the only one disliking the "softec" software that runs this machine.

I was under the impression that the actual waterjet side of the system (being all KMT gear) was quite good and naturally the cut quality comes down to pressure, garnet grade and rate, and cutting speed.

I've found that even on say .100" chromoly having to cut on "extra fine" with the speed at 30% or something to try and eliminate the taper, but we've just lived with the fact theres a taper and the quality guys have to accept that.

in regards to the leadins/outs etc it's a real pain and to be honest I'm sick of it, I'd rather have full control over the machine turning on/off and speeds etc. Lead-outs have an automatic speed that is really really low which leaves a mark on the edge due to the kerf getting larger.

we usually cut quite slow so prefer the lead-out to continue at the same speed, which you have to change manually, rather than it just using the default cut setting. Their response was people usually dont run lead-outs on thin material. If you dont use a lead-out the machine slows down coming to the end of the cut, so the kerf gets larger, and then when it stops there's a delay after the end of the line/arc and it turning the cutting head off. This also leaves a mark.

Programming in Mastercam was somewhat useful (templates for lead-in/out settings, using extend/shorten to create tabs that should be consistent, nesting) but we were importing into Softec, so it was still controlling the speed. I have toyed with trying to bypass Softec, at times starting the cut, pausing it and manually changing the g-code but this seems like a really difficult way to go as softec is always going to have to be there.

Their software does handle a lot of things and makes it "easy" in a WYSIWYG way, but is really frustrating at times and they dont really seem to "get it" when you enquire about it. I have to admit though we get that with our Router supplier too so its not like they're the only ones!

Attached are the lead-in/out settings I was playing with on .100" chromoly.

Feel free to bang me a PM, good to know of somebody else running one of these things, and waterjet in general.

[glenneaux]

Just googled you guys, you are the same guys making the knives etc for people?

I notice in the photo you guys might have a FARO also?

Just to add to the above, waterjet is only a minority of the work we do, we manufacture aircraft assemblies so its 95% aluminium and we route the parts.

Due to that not much time is invested in the machine, so alot of the time we just put up with it. The biggest aspect of trying to program in mastercam was to make things more consistent, quicker to program, and the nesting ability, as being able to nest up sheets and run it big batches is the only way to keep the efficiency up, even though it spends most of its time idle.

The machine is possibly going to be sold off, and to be honest, that doesn't bother me - I'd rather have a turret punch or a much better router (HAAS GR-712?).

[H2Oknife]

Glad to hear your response.
Yes, I have a few knifemakers I blank part for but the majority of work we do is also in aerospace field. We do a lot of thin Ti, Hastalloy, Aluminum etc.
We mainly waterjet and just changed from another mfg machine to the Techni. They did a big oversell job on us with the machine capabilities and we are very in the performance disappointed to say the least. Our 12 year old machine would cut circles around the Techni and the circles would be round. We figured we would try to start using Mastercam since the Softech software was so error prone.

I'll PM you so we can communicate directly.

[yo-1]

Hi
I am working with high precision waterjet cutting machines and have been using IGEMS software for many years without beeing dissapointed once. See igems.se for more information.
I guess they can provide you with the information you need and postprocessors for your machines.

[Learner2]

Just thinking out load. How about you draw a 1/4" circle with spiral lead-in and lead-out. Use the center as the "insertion point", zero point. This will help with the hole's placement. This way, your WJ will cut from the lead-in to lead-out as one line, non stop.

Do the same for any hole sizes you need and save each as a WJ "object" for future use.

BTW we are using Techni WJ systems and the software you are using looks very different to what we are using. Toolpath reminded me of MultiCam CNC routing tables. FYI I am located in OZ not USA.

[glenneaux]

Just thinking out load. How about you draw a 1/4" circle with spiral lead-in and lead-out. Use the center as the "insertion point", zero point. This will help with the hole's placement. This way, your WJ will cut from the lead-in to lead-out as one line, non stop.

Do the same for any hole sizes you need and save each as a WJ "object" for future use.

BTW we are using Techni WJ systems and the software you are using looks very different to what we are using. Toolpath reminded me of MultiCam CNC routing tables. FYI I am located in OZ not USA.

Hi there,

The picture I posted it from Mastercam.

Toolpath is what we use on our Multicam routers.

We use the Techni software with our waterjet, how do you find it?

We are running version 4.65.

Thanks,
Glenn

[Learner2]

Toolpath is what we use on our Multicam routers.

So that I was right. I still have a 4x4 Multicam in my back shed.

We use the Techni software with our waterjet, how do you find it?

We are running version 4.65.

We are running V4.200.69. I find the software to be full of bugs. A lot of the function have no shortcut keys assigned. The "Standard Object" is not editable and can't zoom to select the insertion point. Long list.

Basically we only use it to do basic programming and cutting path generating. We are using AutoCad to draw and the import it into Softec to finish it off.

BTW I just noticed you are in OZ too !!

[rboeser]

Hello, have you tried SheetCam? We have used it for several years without any issues. Very east leadin/out, layer control for inside/outside cutting, ect...

Best Regards, Ron Boeser

[patriqq]

I program 4 Flow machines with "Dynamic" (taper-compensating) heads. My prior experience was on an older non-dynamic Flow waterjet.

WJ manufacturers suggest arc leads for some reason. Don't use them. Try straight in, straight out. To be specific, if a radial line is 0°, we use a 50° lead in and out on thinner material, 10° on thicker material. Also experiment with over-travel (lead-in enters hole at 12:00, lead-out exits hole at 1:00, hole is cut clockwise). Under-travel is also an option.

Our experimental part program is attached (units in inches).

We are now programming with Hypertherm's Pronest. Lead styles are configurable via an excel spreadsheet - you can assign a different style depending on hole size and thickness.

[Tim Hanley]

When running most jets on the best lead in is angled with an arc out this allows for a small overlap and a slower lead out on your arch section this will eliminate the tit on the part, with thinner materials if you have global over ride function you can use it for a more consistent feed rate and adjust your acceleration percentage rate to get rid of a tit or a nick at the end of your cut.