Well, today I broke down some 1/8" hardboard from the building center to use as strut plates.
I got the file all loaded up…there must be some serious wonkiness to my table because it decided that I did not need the center portion of my cut. A lot of the screw holes are not through either. It is super weird because I zeroed from basically where the first screw holes were to be cut and the cnc was still short…
This is still my LR3 spoilboard that I used before and flattened it with the LR3. Maybe I should do a flattening with my LR4? Doesnt look like my LR3 had a good time doing the flattening lol!!
Last night I spent about 3-4 hours with the LR4 trying to flatten my wasteboard.
Unfortunately today I wake up and try to do some more flattening and my Ymin side has decided to not want to keep up with Ymax. The only reason I can think of is that I shut my garage heater off last night when coming to bed. I vacuumed underneath and around the Ymin travel and for some reason it still wont keep up…Super frustrating. When I go to home the Y, Ymin seems to not be square and will crash into the Ymin belt holder before the limit switch engages.
It was a very weird issue that seems to have not been able to be repeated. I tried twice, once this morning and once this afternoon, to replicate the misalignment with homing the machine, and g0x600y1200 to rapid move the cnc. It seems to be happy again and does not misalign the Ys anymore.
Well, the last couple days, I have been desperately seeking advice on why my spoil board was not getting surfaced and my cnc would not cut deeper into my material…I was sure my gcode was fine. I was increasing my depth of cut by millimeters just trying to see if I was just not seeing anything substantial.
It seems it is time for me to eat some humble pie. Turns out, no matter how low you want the CNC to go, you cant go any lower than bottomed out on this thing, determination be darned! Not only am I very frustrated at myself for wasting all that time without realizing this but on a more happy note, I am excited to catch my mistakes and I will have to just add material that I so painfully spent countless hours trying to remove. smh
Today I put a new hardboard/MDF top onto the waste board surface and am in the process of surfacing it. From there hopefully I will have my struts cut later today
I want to jump in and add a few nuggets here. First is surfacing your spoil board is not a huge requirement. It is nice to use as a easy project but it is only needed if you do a lot of Z dependent work (most don’t). Second would be If you are going to do it it is best to do it after you add your strut plates and your machine is very very dialed in. This means Z leveled, and the router trammed. once you add your strut plate the goal is your gantry will be much more straight, so chances are good you are surfacing a gantry bow into your surface that will be gone after you add your plates.
The center of my wasteboard was below what my z could travel so I wanted to make sure things were decently flat. That being said, I will try getting my struts made and I will do my squaring etc after I do that. If I need it, I will do a “finishing flattening pass” after all is said and done. I really appreciate the reminders. Most of this is my “it needs to be perfect” mentality and I have to unlearn that as perfect is the enemy of getting anything done lol.
Unfortunately this was a legacy problem from when I was flattening with my LR3. In reality I should just rip up the top skin of my table and replace it with new so that things are a little easier but I just havent done that yet.
Maybe I will look at the parametric table today when I get a chance. I was successful in getting my strut plates cut out last night. I just zeroed my Z from the dip in my wasteboard so it all cut out properly :). Pictures to come tonight.
I did have enough of a flatness problem that I milled my tabletop flat before adding the spoilboard. However, I realized that it may be easier to just add a shim layer where you plan on removing most of it. I may laminate a 1/4" pdf on to the tabletop and just mill it flat. Then I can add the spoilboard onto the flattened table and not worry about it.
Again, I milled the spoilboard before the strut plates were attached and there is still a dip manufactured into the board. For whatever reason, even when this new MDF top was placed in, the LR4 still had lows and highs in the spoilboard…
How would I take this out if I wanted to do sensitive Z type carvings like say Great Lake Maps and depths for example? How should I go about this? I can get myself a new piece of MDF and retry but I am worried it will continue having the same issue as before.
The way I was successful in cutting these out was that I zeroed my Z in the dipped section so that everything was guaranteed to cut out properly but I wont always have that ability.
Your spoil board doesn’t matter much for this. For anything with a sensitive Z you will surface that before you start your work, it will always be true to the surface of the cut.
So…if I get you correctly, if I just zero my Z above the workpiece at the lowest point of the spoilboard, it will cut through anyway just fine? It seemed like it was like 4mm low in the certain spot. I would think if doing a carve of a tray for example that if I zeroed in the dip, it would cut too deep in the edges of the tray??
