Well I received some V bearings yesterday, installed them on a test board last night, and am very pleased with the results. They track extremely well. I am using the eccentric mounts that allow the bearing sets to be pinched together. I plan to rebuild my machine to use them instead of pipe. We will see what problems I run into along the way.
I will be able to use assemblies from machine #2 to make the build go a bit faster, but I want to spend some time making it cleaner also. Parts to keep are the leadscrews and their mounts, and also my completed Z unit to start with.
The plan is to make a JGRO sized machine with a wrap around gantry. The bed will be torsion box with 1.25” angle iron bolted to the bottom edges and use two V bearings and two skate bearings as shown in the photos.
The bottom of the gantry will be a torsion box. I hope to be able to center drive the gantry as the V bearings should not allow any skew or racking.
The top of the gantry (Y) will be a wood box. I can not decide on whether to use angle iron on the top and bottom, steel strips on the front, or an 8”x22” steel plate for rails. The Y bearings will be a plywood plate with 4 V bearings, two at the top, and two at the bottom to ride on this steel. I am thinking about placing the Y leadscrew at the top of this box.
The gantry sides will probably be 3/4” ply with a stiffener glued or bolted to the outside.
Not sure if I can pull off running the bearing axels through just the plywood, or if I will need some kind of attached plate to strengthen this.
Steve