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People building or using RepRaps.
Re: Geeetech Rostock Mini G2/G2S - Assembly Tips & Modifications - 9 years ago
And if anyone is wondering, my assembly time (first delta printer ever) was only 7 hours from unboxing to power on, even with the mods I had to figure out myself. It's a nice kit - now just to get my Repetier firmware configured...by Ezrec - Delta Machines
Geeetech Rostock Mini G2/G2S - Assembly Tips & Modifications - 9 years ago
I've recently acquired a Geeetech Rostock Mini G2S, and thought I'd share some of the assembly tips & modifications I've developed. I've added them to the RepRap Geeetech Rostock Mini G2/G2s wiki page. Enjoy!by Ezrec - Delta Machines
Re: Powder? - 9 years ago
I'm using granulated sugar as my powder - it's much more IR absorbent than you'd think! I'm using a variation of the High Speed Sintering process in BrundleFab, but using granulated sugar instead of nylon as the powder, and using black inkjet ink instead of pure carbon black. Fine powdered sugar is actually more IR reflective than granular, in my experiments - you might want to use granulated iby Ezrec - Powder Printing and Selective Laser Sintering
Re: Open sorce laser sintering with heated build chamber and piston. - 9 years ago
Granulated sugar is a very forgiving build material - I don't have any warping issues yet, at my 1mm layer height. I don't have a heated build chamber - I just heat the top surface. Sugar retains heat quite well, and once the top layer is up to temp, retains its heat for quite a while. This is neither a good nor bad situation for me, merely observed behavior. My first layer is printed right onby Ezrec - Powder Printing and Selective Laser Sintering
Re: FFF printing in a viscous medium - 9 years ago
... and extending that to a neutrally buoyant fluid: Start with an empty chamber or a mesh stage above the fluid tank Deposit FFM material for the layer (must be neutrally buoyant w/respect to the 'fill' fluid) Either add fill fluid to the tank, or lower the mesh stage into the tank Go to 2 for all layer.by Ezrec - General
Re: FFF printing in a viscous medium - 9 years ago
My favorite idea is depositing powder (ie fine sand) as a support fill from a second 'extruder'. You'd probably need a 5-sided box (either FFM extruded per-layer or part of the machine) in which to hold the powder. The idea would be that you first do the FFM portion of the layer, then 'extrude' the powder support material in the void space of the layer where support is needed (keeping in mindby Ezrec - General
Re: Open sorce laser sintering with heated build chamber and piston. - 9 years ago
About halogen lamps - I use a halogen lamp for pigment-based selective fusing (also known as High Speed Sintering) in my BrundleFab project. My powder bed printer's layer head (for lack of a better word) used a halogen lamp with an aluminum heat shield over it. While developing the sheet metal, I made the decision to fold down, instead of cut out, the sheet metal in the area where the halogen lby Ezrec - Powder Printing and Selective Laser Sintering
Re: best full color 3d printing hotend ? - 9 years ago
With respect to full color and G-Code: Yes, I completely agree. Moving (quickly) to high end devices such as the pcDuino3 ($60 on SparkFun and other vendors) which will allow Wifi, on-board slicing, and direct motor control in a machine specific way, are how we can continue to move on. 3D Printing is currently hampered by: * We are limiting ourselves to very underpowered embedded systems ** Hby Ezrec - General
Re: G code help for dual extruders - 9 years ago
What's your firmware? If you are using Marlin (most common), you can use this edit: 1) Find the M109 Tn Sxxx commands for the extruders near the beginning, and copy those to a clipboard. 2) For each M109 Tn Sxxx, search for all 'Tn' commands (on a single line), and replace with: M109 S0 ; Allow current extruder to start cooling down M109 Tn Sxxx ; Bring other extruder up to temperature Tn ; Seby Ezrec - General
Re: BrundleFab - a thermal fusing powderbed printer - 9 years ago
I've updated my page with my new (v2015.8.23) sheet aluminum layerhead build. I'm still waiting on the ceramic halogen lamp sockets and I2C thermopile, but in the meantime wanted to show off my 3-hour build. (Well, it took about 16 hours of measuring and design work in OpenSCAD first, but the actual build only took 3 hours!) For utlra-light load bearing parts, such as my layerhead, cheap alumby Ezrec - Look what I made!
Re: IWIK3D : The 3D Printer that fits in the palm of your hand. - 9 years ago
For a small printer like this, have you considered an 'inverted built'? The build platform would be above the (inverted) extruder, and would move in Z, X, and Y. This way you only need light motors to control the build platform, and (assuming you had good 'stick' on the first layer) should allow you do very fast build, since the part + build stage should be lighter than the extruder at this scaby Ezrec - Developers
Re: IWIK3D : The 3D Printer that fits in the palm of your hand. - 9 years ago
Looks very interesting. Are you in a very smoky location, or do you have oil on your camera lens?by Ezrec - Developers
Re: Print in metal on conventional 3d printer. - 9 years ago
You could almost get away with it if you had a high temperature tolerant support structure. For example, if you have a dual head system, where one head extruded sand and the other extruded tin or solder. A layer would be a surrounding 1-2mm high sand area, then the tin extruder would fill in the void. Complications involve the embedded of sand in the surface of tin, inter-layer adhesion, and cby Ezrec - General
Re: Thermal binding of sucrose - any prior art? - 9 years ago
Update: (see latest videos and materials experiments on http://reprap.org/wiki/BrundleFab ) Powder Size: Curiously, a finer powder (ground granulated sugar) requires more energy to get to the fusion temperature, not less. It appears that the fine powder is more highly reflective to IR, and requires more ink to achieve the same level of saturation as granulated. This make sense, in retrospectby Ezrec - Powder Printing and Selective Laser Sintering
Re: Thermal binding of sucrose - any prior art? - 9 years ago
Update: I have the pigment-based selective fusion process working, it's VERY tricky with granulated sugar: * The grain size is so big that pooling and other surface tension issues make the layer very uneven * Due to the above, the next recoat pass has a tendency to disturb the layer I'm going to start working with finer grained sugar media, I'll update this once I get something working.by Ezrec - Powder Printing and Selective Laser Sintering
Re: IR reflective polymer available as fine powder? - 9 years ago
Back to the topic at hand - Anyone know of a good source for acrylic powder, in bulk?by Ezrec - Polymer Working Group
Re: IR reflective polymer available as fine powder? - 9 years ago
Ah yes - SIS basically is printing the "mold", right? I can use my sugar printer in that way also, to make positive wax (or chocolate). Although my interest lies in direct object creation at the moment, using my process as a way to generate molds for other materials is a good thing for me to keep in mind. Thanks for the information!by Ezrec - Polymer Working Group
Re: IR reflective polymer available as fine powder? - 9 years ago
I am not using laser based spot heating, but a halogen lamp to do area based heating. The pigmented powder absorbs the IR radiation more quickly, and fuses before the unpigmented powder. That being said - yes, I have observed that the heating phase is critical, and overheating leads to the pooling behavior. its all a matter of dialing in the temperature and durationby Ezrec - Polymer Working Group
Re: IR reflective polymer available as fine powder? - 9 years ago
As you may already be able to tell form the linked wiki page, I am using sugar as a powder medium currently - it's great as a cheap powder, but terrible for 'ready-to-use' objects. One issue I have with sugar right now is correctly handling the fact that it expands in the Z direction when heated, and the next repowder operation scapes the freshly fused layer off. I'm planning a sequence of expeby Ezrec - Polymer Working Group
Re: Auto Desk Resin Formula - 9 years ago
Thank you so much, AutoDesk!by Ezrec - Polymer Working Group
IR reflective polymer available as fine powder? - 9 years ago
I'm working on a powderbed thermal fusing inkjet printer (similar to the HP MultiJet Fusion), and was curious if anyone know of a cheaply available thermoplastic with these properties: * IR reflective or transmissive * Amorphous temperature of approx 150C-190C * Not poisonous when at amorphous temperature * Can be wetted by either alcohol or water (ie, not hydrophobic) * Available in bulk as a cby Ezrec - Polymer Working Group
Re: The Dbot, a new reprap! - 9 years ago
By 'bought accuracy', I mean that often purchasing a square piece of material is often more square than one you cut yourself. The same goes for flatness (which is why sheet glass is such a popular DIY build platform, and my choice of melanine covered MDF for large projects), diameters (ie pipes and rods) and other 'precision properties' of objects. By using a pre-cut extrusion, and basing yourby Ezrec - Look what I made!
Re: The Dbot, a new reprap! - 9 years ago
Looks to require a minimal number of 'vitamins', and a small number of plastic parts - good job! I also commend you for using the extrusion - the 'bought accuracy' of a precut piece is something that few people understand how to use properly.by Ezrec - Look what I made!
Re: BrundleFab - a thermal fusing powderbed printer - 9 years ago
In these material tests, the binder is the sugar itself. The ink cartridge is only used for pigmenting the sugar. The idea is that the colored sugar will absorb more heat from the halogen fuser lamp, and carmelize before the uncolored white sugar. I have other recipes to try for non-caramelized applications, where the fuser will only be used to assist in drying the powder + binder, but they reqby Ezrec - Look what I made!
Re: BrundleFab - a thermal fusing powderbed printer - 9 years ago
The initial intent was to have edible prints, but the thermal fusing of colored areas is my current area of focus. My HP C6602 cartridges still have their original ink, and are a bear to clean out - and probably can never be made 'food safe'. I have a 'clean' unused CISS system for a Canon i9900, and that will be what I will be using for testing food-safe inks, after I have the basic technologby Ezrec - Look what I made!
BrundleFab - a thermal fusing powderbed printer - 9 years ago
I'm working on BrundleFab, a repstrapped thermal fusing powderbed printer, focusing on sugar printing. The theory of operation is very similar to the HP Multi-Jet 3D printer, which lays down binder via inkjet, then thermally activates the binder. In my design the binder is in the powder, not the ink. The ink adds liquid to activate the binder, and changes the heat absorption rate of the binderby Ezrec - Look what I made!
Re: Feedback Wanted on Working SLS/SLM 3D Printer - 9 years ago
So, from your IndieGoGo update, it seems that you now have a commercial backer - congratulations!by Ezrec - Powder Printing and Selective Laser Sintering
Thermal binding of sucrose - any prior art? - 9 years ago
For my BrundleFab sugar based powerbed printer, I am working on a layering mechanism where I lay down black ink on the sugar, then use a thermal pass (halogen lamp from a laser printer) to (attempt to) bind the sugar that is colored, without melting the white sugar. Has anyone seen any prior art on this? The closest I can find is the HP Multi-Jet Fusion process, but this appears to be just curinby Ezrec - Powder Printing and Selective Laser Sintering
Re: hot-end mechanical improvement idea.. - 9 years ago
One way to do this would be to have the filament guide run through the heater block as a smooth cylinder with about 3mm of exposed threads on the nozzle end, and 6mm on the feed end. Then the nozzle would be screwed on to the tube (clamping from the bottom) and a 3mm high nut would screw from the feed side, clamping the top. The tricky bit would be sourcing a good high viscosity thermal compounby Ezrec - Developers