[airbrush]

So before the tool starts cutting i always get a z movement...the tool goes up and comes back down to start cutting...i'm assuming its adding in my clearance plane setting before starting...here is an example of some code below.

The top of my material is 0.855 and my clearance plane of 1". You can see there is a z movement of 1.85 at the start. Wondering if this is a normal thing or can be edited as part of the post(attached my post)?

I usually set my x/y zero first and then my z zero, in this case bottom of part.

Its not a huge concern for now, but just thinking for down the line if i add a 4th axis to my machine, i'll be starting with z up higher and don't want to hit limits....



(FIRST MACHINE SETUP - Machine Setup - 1)

(PROGRAM NAME - A_LETTER.TAP)
(POST - BC_3X_MILL 3-AXIS GENERIC FANUC)
(DATE - TUE. 05/24/2016)
(TIME - 07:37PM)

N01 G00 G17 G40 G49 G80 G20 G90

(FIRST CUT - FIRST TOOL)
(Machine Setup - 1 Z Level Rough)
(Z LEVEL ROUGH)

(TOOL #1 0.25 1/4 2 Flute LOC 1.125 Carbide)
N02 G90 G54 X6.4138 Y-7.4739 S5347 M03
N03 G43 H1 D1 Z1.85
N04 Z1.0855
N05 Z0.9295
N06 G01 Z0.767 F31.0161
N07 X6.2167 Y-7.3325 F62.0322

[magicniner]

Edit your "Setup" in the CAM Tree to set your "Clearance Plane"
It isn't executing a Z move as such, it's simply moving to the start point which you have set or left the CAM to define for you,

- Nick

[MikeC8]

your clearance plane is added to your top of stock, and the clearance plane is used between "features". Its useful for clearing hold down clamps/bolts.

[airbrush]

Okay...just so have this clear...in the machine setup editing the clearance plane there does not affect my clearance plane i've set in my features...correct?

So why the two clearance planes? just so have some insight on its usages...

thx

[MikeC8]

Clearance plane in your setup is the height the machine will retract to above the feature top of stock, is was wrong when I said feature... Still working on my morning coffee.

Rapid, is the distance it rapids above top of the feature, between cuts in the feature

Feed is the height that it will rapid down to, before switching to your plunge feed.

So the difference between clearance and rapid is that clearance is added to your stock thickness, and rapid is added to your feature thickness. Clearance is used between features, rapid is used within features.

[airbrush]

okay thanks. will have to play around with those settings and see what results i get with it...i mainly just wanted to avoid the intital retract it does before starting the cut.

[The Engine Guy]

okay thanks. will have to play around with those settings and see what results i get with it...i mainly just wanted to avoid the intital retract it does before starting the cut.

You should if correctly setup have the top of your stock material at Z0, if that was the case then the machine would Rapid to your "Clearance Plane" setting which is set in the "Stock Wizard", then Rapid down again to your "Rapid Plane" and then it should rapid again to your "Feed Plane" and from there move at your cutting rate as set for your tool.
Normally on most modern machines there would be virtually no discernable stops as the rapid moves are pretty fast, however on some older controls and Mach3 there will probably be distinct stops at each point.

As you have the top of your stock set at a positive value of 0.855 it will move back up again, if it was set at 0 then the Z value would just be Z1.0, it is not usual practice to set Z0 to the bottom of the stock, it isn`t the PP that is the problem, it is the settings you have for the "Clearance Plane" the "Rapid Plane" and the "Feed Plane" where you need to adjust the numbers to get what you want as previously noted by MikeC8

Regards
Rob
:rainfro: :rainfro: :rainfro:

[MikeC8]

95% of my setups have Z0 at the bottom of the part, stock thickness varys to much to get accurate parts setting Z0 at the top of the part in my opinion.

When doing 2 sided parts, either on a fixture plate, or in a vise, I only need to set the Z height once.

[airbrush]

ok, so lets say i set my clearance plane 0.5 and my stock is 0.85. I shouldn't have to worry about any kind of collision during the cutting process since the rapids are going to take care of that.
I guess what i'm asking is when does the clearance plane value kick in?

[The Engine Guy]

95% of my setups have Z0 at the bottom of the part, stock thickness varys to much to get accurate parts setting Z0 at the top of the part in my opinion.

When doing 2 sided parts, either on a fixture plate, or in a vise, I only need to set the Z height once.

Mike

Each to their own, I would never do that, if I had some stock that was so bad I would skim it off and then have an accurate depth everywhere, setting off from the bottom of the stock which could also be variable if the top is would mean that a depth of cut at say 0.5 inch would possibly not be 0.5 inch deep along it`s length as measured from the top of the material.

On a second side cut if the uneven top side is then the new bottom the the part possibly isn`t level, if you don`t have to worry about the top/bottom of the finished part being level over it`s full area then your method is absolutely fine, like I said, each to their own
If it works for you then great

Regards
Rob
:rainfro: :rainfro: :rainfro:

[The Engine Guy]

ok, so lets say i set my clearance plane 0.5 and my stock is 0.85. I shouldn't have to worry about any kind of collision during the cutting process since the rapids are going to take care of that.
I guess what i'm asking is when does the clearance plane value kick in?

A setting of 0.5 will only clear your material by 0.5, it will show as Z1.35 in the code but as the stock is 0.85 of that figure you will only get the cutter actually 0.5 above the material which could be a problem, see below

As MikeC8 said, the "Clearance Plane" which is set in the Stock Wizard is the height the Z axis will retract to when moving from one feature to another so that is the one that really needs to be a pretty high value so there is no possibility of a collision with clamps or raised bosses etc and it moves at full rapid speed.

The "Rapid Plane" is only in use within a feature, for example if you have two pockets in a single Feature in your CAM Tree then when the tool retracts from the first pocket to move to the second pocket it will go at the the "Rapid Plane" setting and will again move at full rapid speed so you have to be extra vigilant if you have any fixtures or raised bosses etc between the two pockets then the "Rapid Plane" setting needs to be high enough to take anything like that into consideration

Regards
Rob
:rainfro: :rainfro: :rainfro:

[Sorin Nenu]

Mike

Each to their own, I would never do that, if I had some stock that was so bad I would skim it off and then have an accurate depth everywhere, setting off from the bottom of the stock which could also be variable if the top is would mean that a depth of cut at say 0.5 inch would possibly not be 0.5 inch deep along it`s length as measured from the top of the material.

On a second side cut if the uneven top side is then the new bottom the the part possibly isn`t level, if you don`t have to worry about the top/bottom of the finished part being level over it`s full area then your method is absolutely fine, like I said, each to their own
If it works for you then great

Regards
Rob
:rainfro: :rainfro: :rainfro:

Hi Rob, I agree with you. How ever, many people in the woodworking business, with larger tables, they always set the Z0. At the bottom (top of the spoil board) they work with sheets that are 4X8 and they don't skim that... I always set the Z0. At the highest point of the part but I am in a different type of work..


Sent from my iPhone using Tapatalk