b height in QCAM

Discussions around the CAM Add-On of QCAD.

Moderator: andrew

Forum rules

Always indicate your operating system and QCAD version.

Indicate the post processor used.

Attach drawing files and screenshots.

Post one question per topic.

Post Reply
Garball
Junior Member
Posts: 15
Joined: Thu Jul 15, 2021 7:10 pm
Location: Port Moody

b height in QCAM

Post by Garball » Fri Nov 05, 2021 7:11 pm

Hi,

I'm preparing a drawing for plasma cutting. For the Tool "Mill', I'm setting the safe distance 'a' as a positive value (10), the start depth (b) to a negative value (-3.8 as per Hypertherm) which I'm assuming is the initial pierce height and the depth of cut 'c' to a negative value (-1.5 as per Hypertherm) which is the cut height. Is this correct for plasma? Otherwise, it would plunge the torch into the work I would think.

How do I select material thickness? The table has a THC.

I am totally new to this and haven't made my first cut yet. My goal is to use QCAD/CAM straight to Langmuir's FireControl software bypassing Sheetcam.

QCAD/CAM 3.26.4.0 (3.26.4)
Port processor G-Code fofset mm
on OSX 11.6
on Langmuir Crossfire Pro table
on Hypertherm 45XP plasma cutter

User avatar
andrew
Site Admin
Posts: 9037
Joined: Fri Mar 30, 2007 6:07 am

Re: b height in QCAM

Post by andrew » Mon Nov 08, 2021 10:48 am

Do you want to cut in multiple passes, lowering the Z axis with each pass or in a single pass?

Garball
Junior Member
Posts: 15
Joined: Thu Jul 15, 2021 7:10 pm
Location: Port Moody

Re: b height in QCAM

Post by Garball » Mon Nov 08, 2021 4:33 pm

Sorry, forgot to say this is plasma.

User avatar
andrew
Site Admin
Posts: 9037
Joined: Fri Mar 30, 2007 6:07 am

Re: b height in QCAM

Post by andrew » Mon Nov 08, 2021 4:43 pm

I understand. I'm still not quite sure what the Z axis is used for. Do you have different profiles at different Z levels?

Garball
Junior Member
Posts: 15
Joined: Thu Jul 15, 2021 7:10 pm
Location: Port Moody

Re: b height in QCAM

Post by Garball » Mon Nov 08, 2021 6:17 pm

Yes. In plasma cutting, depending on the type of material and thickness, the torch height (or tip) must be set at the correct distance. There is a table for that in Hypertherm’s manual.

User avatar
andrew
Site Admin
Posts: 9037
Joined: Fri Mar 30, 2007 6:07 am

Re: b height in QCAM

Post by andrew » Mon Nov 08, 2021 9:10 pm

So if I understand correctly, the torch remains at a constant height, but depending on the thickness of the material you cut, that height is different.

If so, you can simple set

Safe Z (a): 10
Start depth (b): 0
Cut depth (c): -3.8

Start depth (b): 0 means that your material starts at Z=0 (i.e. the top surface of the material is at Z=0. If the torch would move to Z=0, it would just touch the material.

QCAD/CAM will generate G-Code that moves rapidly (G0) to Z=10, then moves slowly (G1) to Z=3.8 (positive, 3.8mm above the surface), cuts the contour and then retreats to Z=10 again. It will never descend to Z=0.

As always, check your G-Code program before you run it.

Post Reply

Return to “QCAD/CAM”