This what I use on my D-bot for the Z axis.
I'm using an heavy 314x314x4mm aluminium bed, and with the original Spauda's build I had some issues with auto bed leveling and ringing.
This setup use almost the same materials than the original Spauda's D-Bot requieres except some specific screws and PC wheels instead of the black ones.
The concept is to use "wheel tensionners" to push on the verticals V-slot. I didn't try it with black wheels but I'm convinced that he pressure will damage them. I highly recommend to use PC wheels. The "wheel tensionners" give 2 advantages :
-It kills the bed wiggles (and so ringing)
-and you can level the back and the front of the bed by adjusting the wheels pressures.
Part of my D-Bot Upgrades collection.
From the original build:
-2 motor mount bracket and the hardware it needs
-6 3x3_plate and the hardware it needs
-6 Corner_bracket and the hardware it needs
-Hardware needed for the lead screw brackets (only the hardware, not the printed part)
-8 PC mini wheels (and 16 bearings)
-8 M5x25mm screws (for the wheels)
-8 M5x16mm screws or longer (for the tensionners)
-8 M5x8mm flat head screws (to fix the tensionners to the rails)
-8 M5 square or T-nuts (to fix the tensionners to the rails)
-16 M5 nylock nuts (to hold the wheels and for the tensionners)
-8 M3 washers (to plug into the wheel holder's holes where the tensionners will push)
You also need to cut the original K V-slot (it is used to hold the Z motor in the original build) 10mm shorter than N/M rails (i.e 453mm in my case, but do your homework and take measurment before any cut)
-8 WheelTensioner part
-2 BackWheelHolder part
-2 FrontWheelHolder part
-2 LeadScrewBracketOffset part (those have the same offset than the Spauda's motor mounts)
For the bed level marks :
-4 M5x8mm flat head screw
-4 M5 square or T-nuts
For the front lead screw :
-2 M5x16 or longer
-4 M5 washers
-2 M5 square or T-nuts
-a 20x20 V-slot off-cut (lenght is not important)
The Printer Frame
First you must get a perfectly square structure. Follow the Spauda's build guide to adjust the top of the frame. Then you must get the rails A/B and C/D parallel to each others. take the top of the frame as reference and adjust distances at the bottom of the frame. Once you get all rails parallels take time to tight every screws. Center and fix the motor mounts on M and L rails.
The Bed Frame
Follow the Spauda's build guide for the back of the bed frame. For the front of the frame use the K rail (cutted 10mm shorter than N/M rails), 2 3x3 plates, 2 corner brackets and center everything. I recommand to build it on a flat surface to get a plane geometry. I you have a 20x20 v-slot cut-off add it on K rail with the 2 20x20_VslotBracket. Center and fix the lead screw brackets on K and Q rails.
The Wheel Tensioners
Don't fix the wheels in the wheel Holders yet.
To simplify the build glue the M3 washers into holes of the wheel holders. Fit the wheel holders to the end of the V-slot and fix every tensioners as close as possible of the wheel holders. Thigh them firmly. Set every m5x16mm screw with nylock nut on all tensioners. Plug back the wheel holders on V-slot and insert all the bed frame into the printer frame (use something to hold it at mid height). Now you can insert the wheels into the wheel holders and fix them with M5x25mm screws and nylock nuts.
Even not tight, the bed shouldn't be able to move out the frame now.
Add the threaten rods.
Start to tension each wheels symetricaly until each wheel get a good contact with the rails.
Get the bed height close to the homing position, it is better to tune at top or bottom of the frame than at mid height.
Regularly try to rotate the bed a bit on Y axis, and keep add tension to wheels until the bed can't rotate anymore. Finally you can use a level along the X axis and adjust pressures to get a bed frame perfectly horizontal. Then test it on the full Z run and keep on adjustements until you get the perfect setup.