@jepho As @NeilFerreri has observed, every instance of Speed being set in the .nc file is a F1181. This translates to a ‘modest lilt’ but nothing like ‘fast’ for the machine to be moving. There is a pre-positioning move that readies Z, which is F590
G1Z-0.0382F590.6
G1X1.5259Y1.4278F1181.1
Although the co-ordinates vary as the .nc file progresses, these speeds are consistent throughout the file. So this is what Carveco’s post-processor is outputting. If your SO3 is not behaving like this, then it suggests the fault is within the machine/controller/config, it is is behaving like this, then the fault is in your Carveco design file, Carveco setup/units/machine config/etc, and/or its post-processor.
You could manually construct a .nc file to move from A to B and back with specified speeds, vary those speeds and confirm that the machine is complying… Taking the preamble from your example .nc files, this could be something like the following - please, any experts who know Grbl better, please chime in/correct.
Copy the following into a text file, and save it with .nc extension:
Hi Neil. I must have explained this poorly. I don’t mind how fast the rapid moves are. Once my zero point is established and the correct X & Y starting positions found via the goto buttons. I usually will work from the centre of the workpiece. I jog the Z into its previously found Z zero height position then hit run. Immediately the speed of the cutter for the roughing path is too fast. I am using a new material as stock (Ash) and I had no idea how it would machine. I was roughing with a two flute 6.35mm x 32mm cutter with a 1mm stepdown, 500mm/min feed speed and 40% stepover with a 250mm/min plunge speed. This should have produced a reasonable feed speed so that I could increase it to the point just below tearout occurring.
My initial move after homing will be at that speed and it does not seem unreasonable. I have a standard sized SO3 which is unmodified apart from the fixture tooling plate, stiffener rods and modular vices and the belt tensioners. It is running Makita 00700CX4 trim router. I keep the belt tension adjust weekly to 135Hz (C3) for all three belts.
OK… Carveco Maker phones home monthly and any adjustments to the software are carried out by the company. I have not been notified of a major adjustment in recent weeks. I will contact them to try and understand why the software is not specifying the speed, I am entering at the toolpath creation stage.
I suppose the only thing that the developers here can address/resolve is why the buttons on the GUI do not adjust the speed.
I will go back and redo the toolpaths for my design file. If this is a setting I have missed or Carveco has in someway started to decide its own variables, I will be a bit nearer to an answer. 1181.1, while consistent throughout the file is not something I have knowingly set. It is also an odd value for anyone to select. I usually stick with multiples of 100 for feed speeds. 500 doubled is 1000 not 1181.1.
Agreed!
This is a good idea so as to test what is actually happening. I will do this after I have had a quick bite to eat.
Ok, just shoot me now!
I had measured and calculated everything in millimetres. When I was experimenting with inlays, I was using some imperial measurements initially because that was what most of the tutorial material worked with. My post processor was still set to imperial () when my work was being completed in millimetres. Please forgive me and thank you all very much for the help. It was very much appreciated.
I believe grbl, by default, only lets you reduce the feedrate to 10% of your programmed rate. You’d have to get down to 30% or so to see a difference as anything over 10000mm/min would default to your 10000 max feed.
How’d the cut go?
Cut in progress:inexplicably fast so I used Textmate to find and replace all instances of F15000 and F30000 with F500. Only the roughing path had this error.The finishing path had f250 and F500 throughout. This is a very fine bit ball end bit with a 4.9 degree cutter angle and a ball end of .25mm radius so I do not want to break it.
It all appears to be fixed now! Thank you gents. This is the completed roughed piece and tomorrow I will machine the finishing touches. This is almost a 7 inch square x 2 inch deep block of Ash. It is a really lovely wood to work and is tolerant of quite a wide speed range. I was feeding from 3000mm/min down to 500mm/min. . I set the base speed to 1500mm/min so that I could increase or decrease it over a wide speed range. The GUI buttons worked correctly.
As the original issue has been addressed, I’m closing this topic. If anyone else has a similar concern, feel free to start a new topic, which will ensure that it is addressed promptly.
Thank you for your efforts, Neil.
) when my work was being completed in millimetres. Please forgive me and thank you all very much for the help. It was very much appreciated. 
