Here is the top section of one of my code files, trying to figure out when it reaches N0240 M98 (HeightSense.tap) it does a G28.1 Z3.00, G28.1 in the guide says it moves at current feed-rate but what is my current feed-rate

Also, what does this line do N0050 F1 ?

Just trying to gain a deeper understanding of stuff.

N0010 (Filename: 65mm Square Circledxf.tap)
N0020 (Post processor: DTHC-HYT-TAP-rev11B With Pauses.scpost)
N0030 (Date: 26/12/2015)
N0040 G21 (Units: Metric)
N0050 F1
N0060 G53 G90 G40
N0070 (Part: 65mm Square Circledxf)
N0080 (Tool number: 106  Distance between Touch-offs: 0  Feedrate: 4100)
N0090 (Preset Volts: 106)  (Suggested Tip Size: 45 ) (DTHC Delay: 1.5 sec )
N0100 (Min Cut Length for DTHC ON : 75 units )
N0110 S900  (Global DTHC ON/OFF is ON )
N0120 M22
N0130 S10 (Turn off DTHC at the beginning)
N0140 M22
N0150 S3106 (Preset Volts set to 106 Volts)
N0160 M22
N0170 S515 (DTHC Delay set to 1.5 Seconds)
N0180 M22
N0190 M09 (Turn off extract fan)
N0200 M00 (Paused: Check the DTHC Settings - Hit RUN to continue)
N0210 G00 X36.000 Y17.475 Z15.000
N0220 M900 (Check for Z active)
N0230 M08 (Turn on extract fan)
N0240 M98 (HeightSense.tap)

I think you answered your own question F1 is the feed-rate (1 unit per).

Tweakie.

I thought that but a feed rate of 1 would be unbearably slow no??

When it does the G28.1 it certainly moves faster than 1

Yes indeed 1mm / unit is indeed slow but it looks like that's what your post-processor decided upon.

I didn't notice a G28.1 in your code.

The default feed-rate is 6 units per so if you have not defined a feed-rate and call G28.1 I believe it will operate a 6 units per.

Tweakie.

You've got some curious code there Dave.

Strange use of the S command.
What's M22 doing?
But mainly what are you doing with M98?

You also have a comment that says Feedrate is 4100 yet you haven't set the feedrate anywhere to 4100 - no comments are bad - incorrect comments are a hanging offence.

Oh and finally WTF is a square circle? 

Ha, lol, square-circle  Yes its a test file i use when trying out new cut parameters or materials, its just a 65mm square with a circle within it - good for dimensional checks, holes, divots, angularity etc.

The F1 is hard-coded into the post-processor, no idea why some sort of basic default maybe.

The post is for a CandCNC THC unit - the M22 codes (i think) flush a previous S command into the serial port and then to THC for cut parameter control.

The M98 is connected to my thread yesterday working on a new probing method, I have moved the G28.1 and other stuff to a subroutine called by the M98, looks like this...
#15239=1
G04 P0.5
G28.1 Z3.000   
G92 Z0.000 
#15239=0                 
G00 Z#15045
G92 Z0.000
M99
%

The #15239 var is monitored by a brain to control a cylinder.

I had not noticed the feed-rate comment there, TBH i never read them really, only the tip size one which reminds me to fit 30A consumables or 45A ones for the job. I think the feed-rate comment comes from the first F call which would have been 4100 for this test (45A on 3mm mild)

Tweakie - even 6 default is not what happens - that would be 6mm/min and my G28.1 starts at 15mm up so it would take nearly three minutes to hit the surface! In reality I would guess it's more like 1300mm/min which is my Z axis top speed

Hi Stirling he is using a Candcnc unit and they use a lot of mach3 Gcode functions to program their THC. Are you back ?? off Holiday

Les always put a F1 feedrate in there becasue at one time Mach3 could startup with a Zero feedrate . It is just a preventive measure that was never removed from the post.

And rememeber these post were created by Candcnc for the most part. Dave is just starting to work out his OWN system for Plasma cutting.

I think you will find that the G28.1 has it's own preset feedrate which is a % of rapid .

Also because the CandCNC units use signal multiplexing it can cause problems controlling pins from a macro . ( Been there)

(;-) TP

Hi Stirling he is using a Candcnc unit and they use a lot of mach3 Gcode functions to program their THC. Are you back ?? off Holiday

Hi BR549 - Ah right - CandCNC - I'll keep clear I think.

Yes I'm back but already beginning to wish I wasn't....

Les always put a F1 feedrate in there becasue at one time Mach3 could startup with a Zero feedrate . It is just a preventive measure that was never removed from the post.

And rememeber these post were created by Candcnc for the most part. Dave is just starting to work out his OWN system for Plasma cutting.

I think you will find that the G28.1 has it's own preset feedrate which is a % of rapid .

Also because the CandCNC units use signal multiplexing it can cause problems controlling pins from a macro . ( Been there)

(;-) TP

I had guessed there was a possible zero feed rate thing or else it would not have been a 1 but something more.

I can't find any reference on how a G28.1 is controlled, all the printed stuff i have read just says it uses "the current feed rate" until i presume it gets to the value in the Z parameter (3 in my case) when it is supposed to slow down more, I think there is a value in SheetCam for that (plunge safety distance possibly)

the multiplexing issue was the reason for my falling out with CandCNC, I had the torch mis-fire problem and they refused to tell me how to de-multiplex the signal, instead, after many weeks, tried to get me to buy a new THC! In the end a kind person prodded me in the right direction and the pcb was marked with the correct jumper position, took 5 minutes and has not missed a beat since.

Look in the Homing config page you will see an entry for %speed (far Right) . That is for setting homing speed to a % of rapid speed.

G28.1  uses the preset speed
G31 uses a Feedrate call

(;-) TP