Best place to put my printer build thread...

Hello all!

I want to start a build thread for a printer I'm making, but I'm not 100% sure where to put it. My first guess is under the "Reprappers" section? I know this forum has specific printer style sections, but I don't think this thing is special enough to fit any of those categories.

The printer will be a cartesian style machine with a build envelope of approximately 24" wide x 40" long x 34" high. The basic frame and support structure will be built from welded square steel tubing. Linear steppers for moving the X and Y axis similar to (not exactly to) these:



The heated Z axis bed will be lifted by four threaded rods on each corner and guided by... I haven't worked that out yet. I'm also planning on using an extruder head that takes pellets instead of filament. I'm hoping the extruder will save me some $ on print material costs.

The purpose of the machine is to help me get closer to casting some large parts in aluminum. The idea is to leverage the printer to expirement with different ways to make tooling for casting these parts. One method I would like to pursue is to print the actual parts in PLA, cover in investment, burn out the PLA leaving a cavity behind to pour molten aluminum into. The printer could also be used to make match plates (tooling) for a more traditional rammed green sand type casting mold.

Anywho, knowing the correct place to put this project would be most appreciated.

Thanks everyone and take care!

David

Edited 2 time(s). Last edit at 01/30/2015 06:05PM by DavidBraley.

My apologies for the dumb questions!!! I should have spent more time reading... (embarrassed)

I guess this is what I'm building:

Repstrap

And there's even a special section for it.

David,

First of all, good luck on your build.

Yes there is a repstrap area below, it's not got much activity tho. Reprappers section would work also.

For what it's worth, here's a couple of suggestions.

- Try to keep it simple. A large-format machine has more time to fail during a print.

- Having an extruder head that takes pellets will make the print head excessively heavy, and will be an additional point of failure. This last weekend I was exhibiting my printer at the World 3D Printing Expo in Burbank with my maker space, and I was in the booth right next to the See Me CNC booth, where they had their enormous 3D printer - about 16 feet tall. This had that kind of arrangement - a pellet fed extruder, and you know what? They couldn't get a good print all weekend (but they did get on the news - good for them). The whole machine would flex because of the added weight, and so the speed and accuracy was terrible. It could not retract - so it was also messy. I think it would be much more reliable to make your own filament bot, and you could make whatever filament diameter you want.

- Plan on having some kind of bed leveling probe. With a large build area it is even more important that it be perfectly flat and level so your first layer sticks, and it needs to be able to level itself if you are going to use it for production.

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My printer: Raptosaur - Large Format Delta - [www.paulwanamaker.wordpress.com]
Can you answer questions about Calibration, Printing issues, Mechanics? Write it up and improve the Wiki!

Thanks Paul! I appreciate your response. I've been reading, and reading and reading... This place is full of amazing people! I am so impressed with the amount of creativity in this community.

My reading has giving me a strong feeling I need to start with a smaller first machine build project. I'm thinking a machine that will still be useful, but less painful to learn from.

I have been scrounging through my pile of interesting stuff (my wife calls it my giant pile of cr#p!) for build materials. I have found some linear rods with matching bearings, and some lead screws with nema 23 steppers and timing belts. The envelope will be something close to 12" wide by 18" long by 12" high based on the materials I have on hand (might be a little different). The machine will still be what this community would call a "RepStrap" because I'll be making it from surplus and scrap I have on hand. It will be a filament machine as well. Hopefully this smaller first build will be easier to achieve success with. I'm sure I will learn a LOT!

I have machine tools here at my disposal, so I'm hoping I can get past any fabrication obstacles. I just hope I come up with some interesting findings in this journey that I can share back. I'm not convinced yet I'm even remotely as clever as most of you.

Take care,

David

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Horsepower determines how fast you hit the wall. Torque determines the size of the hole you make.