Intro

Delta 3D-printers are cool so i decided to build one.

Parts

Speadsheet of all parts is available here. Some of it is in swedish tho.

Build

Extruder

The Mendel Mini Extruder uses 1.75mm fillament and direct drive with a Nema17 stepper motor. It allows you to manually control the feed by turning the large gear.

Hobbed bolt

Linear movement

I decided to use rails with recirculating ball bearings. For this low wight application it's okay to use cheap ones from china. The other alternative i looked at was rollers but the price difference wasn't that big.

After a good cleaning and a bit of oil the movement was smooth and with low friction.

Electrics

I'm using RAMPS 1.4 with an Arduino Mega and Stepstick drivers which is pretty much a standard reprap solution. It's dirt cheap and the step up alternatives are cosmetic upgrades rather than better performance for the printers (ie. Meltzi). Picture shows the RAMPS some of the drivers.

A heatsink is needed for each driver but the chip is really small so the cooling wont be that effective. Use heat conductive glue when attaching the heatsinks and make shure that you dont short any components that are nearby.

Arms/Rods

There are 6 arms needed. I made a jig to make all of them exactly the same length. The carbon rods are 180mm. I used CA to glue them together.

Frame

Upper frame, two flanged bearings make a pulley for the belt.

Hot end

The hot end is a AluhotendV4 1.75mm from 3D Industries in Australia.

I have yet to figure out a good mounting position for the fan since the original Kossel one directs too much airflow at the lower part of the hot end. I think im gonna make some kind of duct that isolates the flow around the heatsink part of the hot end.