I'm impressed but overwhelmed with the openbuilds world. I hope someone can help me get my design nailed down. I'm building a manually adjusted column to position a light sensor (<100g load). Range of motion of ~80cm. I'm picturing two sections of V-slot. One mounted vertically. The other section parallel and able to slide up and down. Locked in place once positioned by a screw with a knob attachment. I think the design in the attached image might work well. The image is from the Parts Store — but I can't find the build details anywhere. Here's what I think I need for the gantry assembly: (4) Solid V Wheel Kit (2) Eccentric Spacer - 6mm (2) Aluminum Spacers - 6mm (4) Black Angle Corner Connector (4) Low Profile Screws M5 - 8mm (4) Tee Nuts - M5 (4) Low Profile Screws M5 - 25mm (4) Nylon Insert Hex Lock Nut – M5 Questions: 1) Does that seem like a reasonable build? I'm looking for something rigid and easy to adjust. Precise only in ± a mm or two kind of way. 2) Does my parts list cover what I need to build the gantry? Assuming I'm attaching a pair of 1m long 20x40 rails. An alternative is something telescoping. I can't figure out if the 20x20 nests inside the 40x40 rail anyway — so that could be a non-starter.
If you go with the Corner method of attaching wheels you need 4x eccentrics. The corners accept only eccentrics to get the spacing correct
The wheel kits also come with the locknuts so you can also strike them off the list. As an alternate suggestion you might also consider the V-Slot Gantry Kit - Universal - OpenBuilds Part Store as it'll save you a bit of money. It is easily adjusted down to fit the 40x40 V-slot. To create an effective braking mechanism consider a Star Grip Knob - OpenBuilds Part Store with a Double Tee Nut - OpenBuilds Part Store set into the track. (You'll need to trim down the length of the Star Grip Knob though to make it fit properly.)