Squeezing Every Inch Out Of Your Printrbot
Bed extensions as well as other axis extensions are becoming more and more popular as owners try to squeeze out every possible mm of usable print space. I’ve decided to give it a whirl on my already large Printrbot Plus. A friend of mine has a CNC and offered to cut the bed and sub-mount to my new specs. I wanted to be able to match it up to the Printrbot parts as well as styling. I took the opportunity to upgrade my rods and bearings as well. I purchased a set of 18″ hardened chromed rods that are specifically designed for 3D printers and other linear motion applications.
The new bed and sub-mount were designed with two 8×8 heated beds in mind. I wanted to be able to print ABS as well other filaments using the entire print bed. The plan is to have an aluminum plate milled with pockets to fit the 2 – 8×8 beds into which will help to keep heating times low. It will also help to heat quicker using two beds wired through individual SSR’s. The thermistors are also planned as a duplicate. A friend of mine as well as a few others have already done this, so with a little bit of help I too shall run two beds. I will control the setup with a fotek SSR or solid state relay. I just talked to my buddy and he said that it does require a little more work than I originally was told but, it’s not rocket science. I will put up detailed information once I get to that point.
Update: I have got some updated information on how two heated beds on one platform will work. There are several different ways you can go about doing this, one way is to build a board that uses SSR to control both beds. The other is to use two pid controllers that run independently of the main controller. The easiest method to implement would be to buy two pid controllers that use k type temp sensors. They typically come with a readout display and you need to make sure they operate in a range up to 150. I’ve seen them for about $20 if you shop around. Amazon.com is supposed to carry them. I will also be using a basic temp sensor setup to monitor the surface temps in 2 places so I can help tune in the pid settings.
For now my plan is to use a custom milled aluminum plate that is slightly oversized and swap out a full sized Lexan plate for printing PLA. I primarily print PLA so having a little bit smaller plate for ABS isn’t an issue right now. The overall length of the y axis is about 17.5 inches and I already extended the z axis to 16.5 inches. My only limit is the x axis which I plan on eventually making wider by a few inches. I have quite a few projects in the works and one of them is a modified printrbot plus that will primarily consist of aluminum parts. The x bridge and carriage have already been finished with a height of about 20 inches and an huge x axis at 16 inches. More than likely it will have a 16-17+ y axis. This is about as large as I have been able to reliable extend the plus’s platform.
Posted from RepRap Squad HQ