[curiosity22]

Hey G'day people,

Feed rate and plunge rate assistance required.

I'm trying to push my cnc limits to see what it can/can't do within reason.

How does one make Z move quicker?

I notice feed rate doesn't affect Z .. feed rate seems to push X and Y but then all that goes out the window when it comes to Z?

Is Plunge Rate what affects Z movement.

Reason I ask is I use UcCnC great program does its job. When I increase feed rate from 100% to 300% X Y move ok provided its traveling in a straight line. When we get to carving I notice that Z speed is traveling at 100% not 300%.

I know I could just as easily go to my cnc and increase plunge rate to equal feed rate - I am opting to be educated by people that know before I go break anything.

Am I on the right track that Plunge controls Z speed? If not what does.

I am trying to reduce the hours some of my 3d carvings take to complete.



Cheers and thanks in advance..

Steve

[ger21]

What software are you using?
In most, the plunge rate should not be the Z axis feedrate.
Are you perhaps already running at the maximum Z axis feedrate?

[curiosity22]

Hey Gerry g'day,

Thank you for replying to my post.

I'm using UCCNC. Aspire.

I'm pretty sure that I'm not running at the maximum Z axis feedrate. but having said that I really don't mind admitting that I wouldn't know how to test for that separately anyways. X and Y are easy tells, they zip along quicker by increasing the numbers. Z seems to move at a constant speed.

Cheers,
Steve

[dharmic]

Do you have a means of entering g-code direct? If so, you could see what different Y speeds do and whether they hit the limit you're encountering.

[squirrel_41]

You are correct it is the plunge rate the your looking for.

[curiosity22]

I can edit g-code directly

Cheers,
Steve

[curiosity22]

You are correct it is the plunge rate the your looking for.

Hey Squirrel g'day,

Thank you for your post - I was thinking that plunge meant something else entirely and never played with it.
Excellent maybe I can shave a lot of time from my carvings.

Cheers,
Steve

[curiosity22]

How are these guys pushing their Z so fast? It looks like any other normal Z Axis granted they seem to have a monster of a stepper there but...

https://www.youtube.com/watch?v=Yxq3piGChg4

Another example
https://www.youtube.com/watch?v=KyAsqOvmTGE


Cheers,
Steve

[squirrel_41]

I can do 3000 mm per in all axis no problem but I am using AC Servos
Are you using Mach3 if so what are your motor tuning values for the Z Axis

[OlfCNC]

With this type of 2.5d works what really matters is how high the acceleration setting is of your Z-axis.
The higher the acceleration the faster your machine can make the movements.
How fast it can accelerate without loosing steps depends on your electronics and mechanics.

[squirrel_41]

And that's why I updated to AC servos I can set the Accel rate to the same as my max feed rates without losing a step

[curiosity22]

I can do 3000 mm per in all axis no problem but I am using AC Servos
Are you using Mach3 if so what are your motor tuning values for the Z Axis

No I'm not using Mach3 - mach3 seems to loose the plot with CV and detail - I use UCCNC which gives me far better results.

homing speed up units 1000
homing speed down units 1000
steps for z is 400
velocity z is 6000
acceleration units 250
comp acceleration units 1200

its pretty much default as imported from mach when I switched over.

Cheers and thanks for your input

Steve

[curiosity22]

Olfcnc G'day,

Thank you for your input, I think I'm with the program as to what I need to do now with thanks. I use a uc100 to talk to a gecko 540. Helical gear and rack unit is rock solid the electronic I guess they are ok the Gecko is functioning as well as it can be. The UC100 does far better than the parallel I used to use.

And yes you are absolutely right for Bas Relief work Z movement is king.!!!!!

Where most of the time is used up in the Bas Relief work I do is in Z movements!! that's 90% of the job if I can shave 30% of there I'd be a happy bunny. As it is I have cut my average work time down in half since upgrading my cnc - totally new rebuild.
The average for a 600 x 400 job was talking depending on complexity of design 10 hours to complete including the roughing.

I'm down to 4/5 hours and that's pretty much with running my new rig as is no experimentation out of the box. I've kept the format of my cnc the same size 6ft x 8ft.

So If i could cut my job time down to 2/3 hours well what to say.

AC servos I have no idea of the cost of the servos or the electronics to go with it. So I would have to do research there. or if it is possible to upgrade just the Z movement to servo and the rest to remain the same. I don't know if that works or can work.

Otherwise cutting a straight line Im fine.

Cheers and thanks for the input.

Steve

[OlfCNC]

Hey curiosity22,

I'm using the UCCNC aswell and it gives me better results than Mach3 aswell.
When running relief works what really counts is the Z axis acceleration value. The higher you can get that value the faster your machine will finish the relief.
Try, experiment and set the accel for the Z as high as your drives and machine allows.
Also try to tweek on the linear error and corner error parameters. I learnt that for reliefs if I set these to 0.2..0.3 makes a larger error but does not matter for reliefs and it runs the path faster.
Remember I'm in the EU and using metric units, millimeters. :idea:

[curiosity22]

Hey curiosity22,

I'm using the UCCNC aswell and it gives me better results than Mach3 aswell.
When running relief works what really counts is the Z axis acceleration value. The higher you can get that value the faster your machine will finish the relief.
Try, experiment and set the accel for the Z as high as your drives and machine allows.
Also try to tweek on the linear error and corner error parameters. I learnt that for reliefs if I set these to 0.2..0.3 makes a larger error but does not matter for reliefs and it runs the path faster.
Remember I'm in the EU and using metric units, millimeters. :idea:

Hey Olf g'day,

Thank you for the tips, I will have a play sometime tomorrow and see what I come up with. I will set linear and corner to your suggestion as well and see how that goes as well.
Fantastic thank you very much and I will advise on how it goes.

As a by the by what type of relief work do you do? Post a pic if you like would love to see your work.

Regards,
Steve

[OlfCNC]

No probs.
I'm making hard wood works for carpenters and restaurators.
Most of works are low QTY (mostly single pieces complex parts, sometimes with scanned/designed 3D models) contract manufacturing and I have to sign NDAs and can't take photos ... not allowed to share these works, sure not on public forums.

I'm also making plasma jobs, but those are for different companies, different industry.

[FastFarmer]

I'm using UCCNC. Aspire.

The videos you posted are using a parallel raster. In such cases Aspire makes no distinction between X, Y, or Z feedrate (another of my Vectric annoyances... lol) and all speeds are the same. Plunging is when you begin cutting a slot or pocket into the material and the cutter is surrounded by material with nowhere to go. In other words these videos have nothing to do with plunging.

Cheers

[curiosity22]

Olf G'day,

Understood and thank you for the tips they are greatly appreciated - can't wait to fire up the CnC tomorrow and see it move faster ...

Have attached sample of the type of work I'm doing.

Regards,
Steve