Builders/Lasercut Variations
TechZone Remix Variation
The TechZone remix, is a lasercut plywood Mendel variation. The ENTS purchased version used V3 electronics based on the Sanguino. The electronics boards are very small, and do not fit the pre-drilled mounting holes on the vanilla face plate and electronics support plate. This is probably because the variation promotes the idea of having a separate electronics plate, and not mounting them onto the standard locations.
The purpose of having separate drives for each stepper, is that often errors in assembly may damage the stepper motor drivers, and they may have to be replaced from time to time. As well these drivers run hot, so some sort of heat sink is virtually required. For production units plan on buying a fan kit.
The Mini-SD socket was removed from the Motherboard, because it was not well used by the customers. but can it seems be ordered from TechZone if required.
You should expect to have to replace the belt drive cogs, as one of your "Build" projects early, if only because the laser cuts, are offcenter, and as a result, the cogs are not perfectly concentric and will eventually stretch the belt.
The belt drive for the Z axis, projects below the corner pieces of the frame, requiring some sort of base, or box with cut-out sections where the belt runs, or as some have suggested, rubber feet, which will need to be tall enough to clear the belt drives. These were not supplied.
Care must be taken when installing the wooden cogs onto the stepper motors, as they have been known to crack, and split. Luckily our version came with extra cogs. The exact placement of the wooden cogs on the steppers, is a matter that does not seem well documented. The thickness of the wooden mounts determines where on the shaft the cog should be, and this is different for each Stepper Motor.
Parts are generally well supplied, with the slight exception of the bigger washers, which can be easily substituted for using SAE 5/16 washers, and the motor mounting bolts, which were slightly short in supply. If only because they are also required to mount the end-stops. There seem to be enough locking nuts for replacement of the few that fall on the floor and skitter off in some unpredictable direction.
The TechZone Remix plywood Mendel, should probably be thought of as an axis by axis replacement project, as the plywood seems to be minimized to keep the costs down.
Essentially the Techzone Mendel, replaces each axis separately and this will allow you to build a more stable plastic version. Making it a RepStrap as well as a hobbyists version.
The guide rods that come with the kit, were rough and unpolished. This offended the old hands, who thought that they should at least have some polish, which was quickly applied to "Knock down" the rough spots.
As well, some of the parts seemed subtly skewed and not all the slots aligned, suggesting that there were some problems in the Laser cutting and assembly jigs, that were not yet straightened out.
Because of supply problems with North American Belt companies, the Belt sections supplied had been "Ripped" to fit the application, and as result there was some variation in width along the length of the belt. This variation in width needs to be accomodated, and as a result it is recommended that you add a few more washers on the idlers in order to make the belt guide width large enough for the thicker areas of the belt. The design seems to require that toothed belts go over bearings with the teeth down against the bearing. The result will probably be an inconsistency in the belt tension each time it hits a tooth. I think a simple cog-shell around the bearing would allow the belt to travel more smoothly, but this would require a slightly different location for the bearings as they would take up more room. Grysmith 19:21, 29 November 2010 (UTC)
