That might be workable but doubles the length of the whole thing. I have more thinking to do.... Thanks!by the_digital_dentist - Mechanics
You can make a spool out of any two discs and a smaller cylinder. Maybe you print the cylinder and screw on the discs. Better yet, copy what Reelex does and keep the filament without spools.by the_digital_dentist - General
This is what I am talking about: The nuts and motor are fixed, the screw is free to rotate and move axially. The screw and nuts are standard hardware store stuff. This is not intended to be a high precision mechanism. I am a bit concerned about the screw chewing up the belt, but not too concerned about lubrication. My biggest concern is how far the belt may shift up or down along the screwby the_digital_dentist - Mechanics
That won't work. I need to turn the screw and have it move in the axial direction. This isn't linear positioning in the traditional sense...by the_digital_dentist - Mechanics
I want to drive a 15mm diameter screw with a motor on a fixed mount at a very low speed, maybe 1 rev/min. The 800mm long screw will be turning through some fixed nuts so will be moving in its axial direction as it rotates. I am planning to try using a 25mm wide flat belt that goes over a pulley on the motor shaft and directly on the screw threads. The pulley will have a center hump to help keeby the_digital_dentist - Mechanics
Terrible product, poor support, no service, late shipping, over-charged payment card, refused to refund overcharge, stay away, don't buyby the_digital_dentist - General
Terrible product, poor support, no service, late shipping, over-charged payment card, refused to refund overcharge, stay away, don't buyby the_digital_dentist - General
Terrible product, poor support, no service, late shipping, over-charged payment card, refused to refund overcharge, stay away, don't buyby the_digital_dentist - General
I suggest that you use fully supported guide rails or linear guides instead of end supported rails, and I would add at least one more drive screw at the front edge of the print bed. Use lead screws and drive them with a single motor to prevent misalignment of the bed plane.by the_digital_dentist - Reprappers
FDM printing is an inherently unreliable process. Congratulations! You have discovered that using host software running on a computer makes it even more unreliable. Now you have a choice- look for software that is less unreliable, or ditch the computer and print from SD cards. Why do you need host software?by the_digital_dentist - General
After some basic tests and adjustment, I plan to make cordials filled with Mountain Dew and Gummy Bears....by the_digital_dentist - Look what I made!
There's a google group for smoothieware support. I suggest you post there- the developers frequently read and respond to inquiries there.by the_digital_dentist - General
What is the plan for its use? Will you be applying tape of some sort and printing directly on it, or stacking up glass or other layers on/under it? 2mm thick aluminum is quite flexible. It probably isn't very flat to start with, and will surely flex more when you adjust the leveling screws.by the_digital_dentist - General
I suspect that getting a good seal from a fully printed ball valve will be a problem. You might be able to get needle valves to work provided you print with the layers in the right orientation.by the_digital_dentist - Object repositories
My experience with smoothie is that if it behaves strangely and that behavior cannot be explained by any logical means, the best thing to do is to try a different uSD card that contains the config file. I spent about a week trying to troubleshoot a Y axis problem that had no logical explanation until someone suggested I try a different uSD card. As soon as I changed cards, the problem disappearby the_digital_dentist - General
Be sure the extruder is calibrated using the thinnest layers you intend to print before adjusting the X and Y axis steps/mm. The mathematical calculations based on motor steps per rev and pulley tooth counts are first order approximations. Cheap pulleys cannot be expected to have accurate/precise diameters and therefore you may have to make adjustment to compensate. A small error in the diametby the_digital_dentist - Reprappers
I can't tell much from the fuzzy, small picture, but if you're using the same gcode file that may be the problem. Filament diameter varies from one spool to the next. If the new spool is different size you need to reslice unless you're using volumetric extrusion. In either case, you have to measure the filament diameter and multiple places (try 20-30) and calculate the average value. Use thatby the_digital_dentist - Reprappers
Coex3d make excellent ABS. I have not tried their other materials yet. I know they get a lot of boos from the community in general, but I have always had good results printing with Octave ABS filament. They make some great fluorescent colors.by the_digital_dentist - General
Folger Tech has 9mm wide GT2 belt with glass fibers embedded in it, but its about as good as everything else they sell. If you want higher quality (probably) look at Stock Drive Products Part Number: A 6R51MC090 The whole point of a belt is that it can flex. If you don't want flex maybe you need rack and pinion gearing instead of a belt.by the_digital_dentist - Mechanics
I am using one removed from an Epson ink jet printer.by the_digital_dentist - Reprappers
Those little springy levers combined with the internal mechanical hysteresis of the switch itself make zeroing a very imprecise process. Pushing on the little nub on the switch is better. I recently switched from that to an optical Z endstop and find there is no hysteresis, so setting it is very easy and precise- no turn-until-it-clicks-then-back-off-1/4-turn type nonsense.by the_digital_dentist - Reprappers
My printer has 305 x 317x 280 mm print envelope and is very rigidly constructed. The frame is built from 1.5" square 8020 aluminum extrusion and uses dual Z axis lead screws with one drive motor and belt, and with fully supported guide rails. I used linear guides in the X and Y axes, and the Y axis is driven by a ball screw. You can see it by following the link in my signature, below.by the_digital_dentist - Extruded Aluminum Frames
Linear guides are very unforgiving of misalignment. If your machine's frame or the aluminum piece joining the two bearing blocks has any flex, you may have problems with binding if you use a single screw on one side. I like the use of linear guides, but I think you should also have leads screws on both sides, driven by a belt and a single motor. If you're going to the trouble and expense of usby the_digital_dentist - Extruded Aluminum Frames
http://imgur.com/a/ScPIV So much for the idea that FDM is useless in large volumes...by the_digital_dentist - General
I think it would be difficult to have most people build a printer during a one day class, especially if they're building different kits. For most, just tuning and getting it printing reasonably well in one day would be a challenge, even with knowledgeable assistance. I'd go for a much longer class to get machines built, or have people build at home as complete as possible then bring them in forby the_digital_dentist - General
When I said "higher than rated voltage" I was referring to the power supply voltage, not Vref. Vref is used to set the average current through the motor. The motor's torque spec is based on a specific current. That current results in the maximum allowable motor temperature, usually around 60-65C. So, if you run a motor continuously at its rated current, it will get hot. If you don't need allby the_digital_dentist - Reprappers
The voltage rating of the motors is not important except that you want them to be as low as possible because that implies low resistance which also usually implies low inductance. The current determines the torque they produce and the motor driver uses PWM to limit the average current to the set value. Operating from higher than rated voltage increases the speed at which the current rises in thby the_digital_dentist - Reprappers
Acceleration of 3000 mm/sec^2 is unnecessarily high for the Z axis. I'd crank it down to 500 or less and see if the problem doesn't magically disappear.by the_digital_dentist - Reprappers
The coefficient of thermal expansion of aluminum is 22.2 um/m K. Unless my math is off, if you have a 1/4" aluminum plate and heat it 80C above ambient, you should get about 40 um of expansion. If the temperature difference between ABS and PLA printing is 30C, the change in the bed should be well under 20um. 20um isn't enough to require rezeroing. Even if you need to rezero when switching bby the_digital_dentist - General