... here are two images of a DIY vinyl-cutter head and the result - should be doable with the reprap too ... Viktorby VDX - RepLab Working Group
Hi Torsten, ... thank you for the infos! The problems with viscosity at very fine nozzles are the main reason why i'm working with fluids and pastes at room-temp instead of FDM For an even smaller/finer application i developed a sort of pico-dispenser capable of dispensing droplets in micron-size (or even in submicron-size ) - look here: at the atached image "Folie3.jpg". The array is madeby VDX - Mechanics
Hi energetic, ... look here, at the last page: When you grind the tubes short, you can dispense extreme viscous pastes too and the smallest ID is 0.172mm (0.0068 inch) - but then you're highly limited by viscosity too Viktorby VDX - Mechanics
Hi RusLan, ..."CNC-завод" is a funny translation for "computer/numeric-controlled milling machine" The last years i was milling and fabbing high precision parts for microassembly and sensorics with my different CNC-mills applying different toolheads. I have an old CNC-mill at home and got it running with different standard CAD/CAM programs. Actually i'm repstrapping with this system and a paby VDX - Russia RepRap User Group
Hi RusLan, the translations are sometimes really funny, but OK You can write in plain Russian, but my answers would be best in English ... I have a CNC-mill and some toolheads for paste-deispensing and low-energy laser-cutting (1Watt laser-power, enough for cutting good absorbing foils). When next weeks i'll get a 20Watt-laser, then the next toolhead would be a sintering device for melting pby VDX - Russia RepRap User Group
... look at the 3D-printers from Z-corp or the DIY-inkjet-3D-printers - here a roll pushes the powder from a reservoir over the building area and then the inkjet rints the next layer of glue. Something similar schould be possible with sand or another supporting powder, but then you have to cover the complete building area, instead of some virtual enclosing shells with a co-fabbed border ... Vikby VDX - General
... smaller inner diameters need more pressure, so you are limited by the stability of the fixings ... increasing force/pressure tends to damage the extruder! Viktorby VDX - General
... i was thinking another way: With lowcost high-power diodelasers (i already have an 1Watt type with fiber and 0.06mm spot and will receive soon a 20Watt-LD with fiber and optics too) you can build a powder-sintering device, where the toolhead can melt/sinter a prelayd powder-surface or even better - apply powder through a small tube and melt it to solid or leave it as support. So you can 'drby VDX - General
Hi RusLan, ... yes, i know the anecdote in German too: "Hängen nicht laufen lassen!" And yes, i lived some years in Latvia (1965-1971) and can read and understand plain Russian, but can't write it accordingly I'm native German speaker, can understand Russian and comunicate in English, so there is some basis for interaction, but you need more people around your location or you can't start a sby VDX - Russia RepRap User Group
Hi Murray, i need something thixotropic, maybe filled with talc or micro-spheres/balloons, what's stable for more than two days in the syringe but can be cured within some seconds by heat (e.g. diode-laser for punctual or IR-bulb for area) or UV ... Viktorby VDX - Plastic Extruder Working Group
... you'll have to find someone who translates the pages - especially all infos about repstraping, as the common sources aren't localized around ... Viktorby VDX - Russia RepRap User Group
Hi Starglaze, where are you located? I'm interested in other curable materials too - either UV or IR ... with IR (or heating) you'll have the advance of easier/cheaper sources. This materials should have two major properties: - long potting time for storage - fast response when activated/cured I'm searching fluid materials which can be stored months and curing-times in seconds to minutes ...by VDX - Plastic Extruder Working Group
... look here: ... especially at the atached image in my 3rd post: With paperwork you can make some really complex 3D-parts out of 2D-sheets ... Viktorby VDX - RepRap Host
... for a tracking accuracy comparable with 0.1mm and a building area of say 50x50x50cm you need two high precision cameras with estimated 30 megapixel and very good optics or a really sophisticated image-correction-program ... that's 'slightly' above the budget of most reprappers >< Then linear encoders or triangulating strings with radial encoders sounds better Viktorby VDX - General
... it's really that simple ... the only limitation is the variable-size for the data containing the actual position. When moving/positioning with an stepsize of 10 microns and using long Int you have a max. linear count of 4.63 kilometers per axis A much more serious problem is the possible speed - imagine an object of 1x1x1m size printed with an accuracy of 0.1mm (not really fine ) with a faby VDX - General
Hi John, ... good findings The motors should be enough for a small CNC-machine - you can measure the resistance of the coils for first estimates of the support-voltage. Encoder could be usefull too ... if not, then you have a second shaft Viktorby VDX - Mechanics
... with so big steps it's a problem with speed and resonancy-errors My CNC-mill has 0.025mm at fullstep and then max. 2000Hz without load, so a max. speed of 50mm/s ... with halfstepping i can go until 6kHz freerun, so max. 75mm/s, but sometimes with stepping errors too I have direct-coupled motors, the Mario robot toothbelts, what's more damping, so maybe some more speed too, but for whatby VDX - Mechanics
... this seems to be really fast - maybe wrong? My (max. 10kHz) microstepping drivers manage 50mm/s with halfstep@4kHz (errors when faster ) on a 5mm/rev spindle ... then 31.25mm/s with 1/8 microstepping@10kHz and even slower when higher microstepping (but with higher accuracy ) Next tim i'll receive some 200kHz- 1/50-microstepping drivers with corresponding motors - then i'll estimate nearly 1by VDX - Mechanics
Hi all, look into the documentation of a comercial paste-dispensing 3D-roboter: It's an extreme simple setup but has a price of 5000 Euros Anyway ... it's much lower parts count, than any other actual system Viktorby VDX - Mechanics
... it's not really that simple I've some steppers (uni- and bipolar) with 24Volts@0.2Amps in contrary to steppers with 1.2Volts@3Amps. For driving with a simple discrete h-bridge (2 transistors per coil) the 24V@0.4Amps are better ... but when you're driving with a modern IC you nby VDX - Controllers
Hi Nadir, ... have you converted your model to triangulated surface (so any polygon is cut into aligned triangles)? AFAIK this was a common Error when exporting from programs like Lightwave or older 3DSMax versions ... Viktorby VDX - RepRap Host
... frag mal bei RepRapSource nach: Viktorby VDX - Altes Forum
I made some experiments with paste-dispensing and printing/sintering interchanging layers of ceramic and gold. The ceramic-slurry was mixed from micron-sized ceramic powder and waterglass, the gold-paste was a mixture of eutectic gold-tinn-alloy spheres (30 microns, 80% Gold 20% Tin), 1 micron sized gold-dust and Dexpanthenol. I presintered the layer with a 4Watt-diode-laser and cured the complby VDX - General
... look at the last image in this PDF - a perfect method for making 'endless' belts with any size ... Viktorby VDX - Mechanics
... look at Caligaris Truespace - it's now for free (until Microsoft smash it completely down): I'm constructing 3D-parts with high complexity for micromechanics with Lightwave - and for solving some specific problems, sometimes with 3DSMax. Most 2D, 2,5D and 'simpler' 3D construction is made with IsyCAM suited best for my Isel-CNC-mill. You have to look at your aims - best 3D-working is withby VDX - 3D Design tools
... oder bestell dir den Arduino oder den Mega bei RepRapSource oder Watterott - knapp über 20 Euro für den Arduino bzw. etwas über 50 Euro für den Mega könnten noch drin sein und sollten dir erstmal über die Wartezeit hinweghelfen, bis Iain in die Gänge kommt. Bei mir liegt ein Mega und zwei MySmarts168 herum, bis ich die anderen Baustellen soweit fertig habe - aktuell haben Dach dämmen, Weihnaby VDX - Altes Forum
Hi Bo, you know about BitsfromBytes in England ( ) and RepRapSource in Germany ( )? Viktorby VDX - Reprappers
... online-position-feedback should solve most issues with sagging. I was thinking about applying rotary encoders and some wires as in my string-tripod Alex Jonis Toy ( ) for triangulation of the toolhead - so with cartesion or angular positioning you can measure the position of the toolhead regardles of structural or other displacement ... Viktorby VDX - General
... wouldn'last very long Better print a mould and make some from silicone/rubber with embedded steelwires or such ... Viktorby VDX - Mechanics