Hi all, For my Ooznest Workbee, I purchased the all popular XYZ probe when I got the Machine. As you probably know, the under side of the probe is designed to align at the corner. Whilst I initially used this probe - I don't bother anymore. I have a right angled square set up at machine x0 y0 which is where I typically place my workpieces. It would still be of use to set Z height for the workpiece surface. I cannot do this with the square next to the piece and also I generally like to set the Z height around the centre of my piece rather than the corner which the XYZ probe is unable to do. Either I can use a piece of aluminium with a flat underside and transfer the wiring over or buy a generic z probe. Either way, Ill have to program the Duet 2 to account for the depth of the new device I so wish to use. I have been through the documentation of the Duet outlining the G codes and M codes specifically for the duet 2 but I do find it slightly difficult to understand so I do not want to mess around with it too much. Can someone with better knowledge please assist? TIA.
Can use the XYZ probe for that. Just flip it upside down Not sure of the Duet side of things, we run grbl/grblHAL and our CONTROL software handles that all with the built in wizards
As @Peter Van Der Walt said, just flip your probe plate upside down. What version of Ooznest's firmware are you using? There should be a a probe Z only option in the firmware. If not, let me know and I'll guide you through creating a macro for it. Alex.
i wired up a hefty limit switch front right of machine to the probe input on my blackbox, set a g30.1 thing over it and then made a macro to probe for z height , works sweet as a nut. you can just make it out bottom right of this image. absolutely no idea whether that can work with your duet but i find it convenient and pretty accurate. home machine and then do the macro and height of tool is done
haha - Flipping the probe upside down - why didn't I think of that? (rhetorical question LOL) I will use this going forward. In terms of firmware - I am on the RRF 3.5 and yes, I am able to probe Z in isolation. Thanks for your suggestions Steve - I would love something like that as would take away the need to plug in the probe and then unplug it again - in terms of the macro, are you referencing from the spoil board surface rather that the work piece surface. Thanks.
ats yes 95% of the time i ref the spoilboard . that often involves a face operation but i know then that everything is where it should be height wise. the old paper trick only gets you so far especially if your engraving something. the thought of having more wires hanging around with a separate probe fills me with dread. ive never measured how accurate the limit switch is but im not making parts for aerospace so not a major issue...
My probe is always connected. I have a 'garage' for it to 'park' it when it's not in use next to the top of the spindle on the gantry. The wires don't have to be long since I too only use the probe for the Z axis.
Yes the old paper trick is guesswork to a certain extent and really depends on the level of accuracy you need. I more consistent method would definitely bring some stability to my life. Thanks man
I don't know exactly what you make with your machine but you would have to be sure of the height/thickness of the workpiece - do you measure each piece? Also, with going through to the spoiler board and raising the woodfibres adjacent to the cut line may cause inconsistencies in where the surface of the workpiece actually sits?
If you're probing off the spoil-board, the workpiece thickness has to be entered into the cam program so it can calculate safe travel moves above the job and also the actual cut depths of your work - carves, pockets cut-outs etc, are all referenced off the spoil-board, not the top. For your second question, do you mean "munching up" the spoil-board surface? If so, that shouldn't really happen on a "zeroed " spoil-board. [if its level and surfaced correctly] because the cutter can never go below zero - it might scratch the surface though. It can happen however, if you probe from the top of the work-piece and the piece is not uniform in height. As Craig commented above, I too mostly zero off the S/B except where it's impractical to do so because there will always be some instances when probing from the top is desirable. When zeroing off the spoil-board, I actually go further, and use a 0.1mm shim under my probe base when probing so as to leave a skin on the bottom of the workpiece - easy to sand off and no damage to the spoil-board.
Yes I understand the workpiece thickness had to be fed to CAM program. I meant in terms of consistencies in the thickness of the material you may be cutting. I.e I am mainly cutting plywood of varying thickness and I would expect inconsistencies in thickness. But I guess this variation in size would be very slight. Yes exactly what you said about munching up the spoil board. I have read someone post that they almost always zero from SB but was not aware of the reasoning - so this info is of much value at this stage of my learning curve. Thanks.
It is a SpoilBoard. Not a "i want to keep $5 worth or MDF pristine for life"-board lol. Its a consumable (;
pete, whilst i agree, it is great to run a complicated program with 3 or 4 tool changes and not touch the spoil board. it makes me feel like i know what im doing!!
It cuts perfectly through the material and barely touches the spoilboard. I started doing it this way because I got sick of chewing up the spoilboard by zeroing on top of material that was inconsistent in thickness. That damages the spoilboard far more. You have to know the exact thickness of the material for zeroing on top as well if you do not want to cut into your spoilboard. For measuring at the spoilboard you do not have to be as precise on thickness because it will always cut to the zero point. I do this for flat plates that do not need ultra precise pocket depths. That being said, I use a caliper to measure my material so it is still accurate. If I am cutting something where the pocket depth has to be precise in wood, I do a surfacing pass on the material because I have yet to find a piece of wood that is consistent the whole length/width. After surfacing, the pockets will be accurate because now the material thickness is known as well as the z location in relation to the bed. Another benefit is if using double sided tape to hold the material down, I add a piece to the top of the z probe so when I flip it over it will subtract that much out of the cut depth. Therefore I never cut into the tape and gum up my endmill. For 3D carves, I always place the model at least a mm below the surface of the material, so I have that as a fudge factor and I do not worry so much about consistent thickness. I just want to make sure it cuts the full depth to the spoil board.
Sometimes my spoil board is a metal vise. Though, I usually put a spacer under the material because I m scared of hitting the vice.
