Had a heart stopping moment in the shop today, I thought my z-axis problem had returned, well almost.
Doing some engraving (just playing really) this is going well I thought, but all too soon I noticed that the engraving was getting a lot shallower. I let it finish then had a look at the code, seemed to be ok.
Had a look at the material and then saw a slight bend in the middle must be flexing I thought.
Removed from mill and then realised that the rear edge of the sheet had a burr, obviously enough to make a difference as I was engraving at 0.25mm depth and the slightest out of kilter will have an effect at that depth.
So after my playing I now have 2 things to look into,
1.0 how to hold flat sheet flat.
2.0 Make an engraving cutter that is spring loaded to take into account irregular surfaces.
Well thats enough to be going on with for now.
I obviously need to stop playing!!!
Any designs for an engraving cutter!
I dont have any details but some time ago a member sent me this pic showing what he was working on:
Thanks Lee, thats almost what I want. The one pictured does not have the nose shroud to control depth of cut as in the manual engravers but it goes some way to show the spring arrangement taht will allow for irregular surface height etc.