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General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: Dissolving PLA used as support for ABS prints - 12 years ago
Thank you for the update. It will be a nice finished product.by Bertho - General
Re: Stratasys's mojo : throw-away hotends - 12 years ago
Thank you for the info. Do you have a picture of the gearing and the drive wheel/mechanism? Berthoby Bertho - General
Re: Dissolving PLA used as support for ABS prints - 12 years ago
It sounds reasonable but audio power amps are not made to continuously operate at those frequencies and can easily overheat. There is no mentioning of tuning the system so it will be resonant. Many ultrasonic generators required a counter weight mounted to the other side of the transducer to operate efficiently. Plus you must have the unit tied to a PC if you do not design a separate signal geby Bertho - General
Re: Dissolving PLA used as support for ABS prints - 12 years ago
I initially heated samples in my first set of tests but not for a long time. Afterwards I left the samples in the solution for several weeks but there was not a significant change in appearance. So in summary, it looks like ultrasonic is needed. Maybe if it was at boiling temperature but that adds significant risks and also possibly warping the desired object from the heat. Berthoby Bertho - General
Re: Dissolving PLA used as support for ABS prints - 12 years ago
That is exactly what I wrote and I included the link to that video.by Bertho - General
Re: Dissolving PLA used as support for ABS prints - 12 years ago
I expect that the ultrasonic cleaner will make a big difference. The grade is not important. I happened to have it available and I wanted to know accurately what was used for the testing. Sometimes store cleaners are mixtures but I do not think it is critical.by Bertho - General
Dissolving PLA used as support for ABS prints - 12 years ago
Success: I tested with an ultrasonic cleaner and laboratory grade Sodium Hydroxide @ 60°C and got a surprise result: Berthoby Bertho - General
Re: Stratasys's mojo : throw-away hotends - 12 years ago
I appreciate that you are taking the time to help. The link works fine from Firefox but presumably it is archived. I accidentally declared the page private so that is why it could not be seen. It is fixed now. I just started this blog and I have a lot to learn and on top of it English is my second language, I grew up in Sweden.by Bertho - General
Re: Temperature Issues - 12 years ago
Measure the voltage across the thermistor as close to it as it is accessible in your wiring and look for drastic changes when it is intermittent. It will help you to know when and where the intermittent occur. Secondary, then measure the voltage as close to the microprocessor as is possible and it will help you isolate where the problem occurs.by Bertho - General
Re: Stratasys's mojo : throw-away hotends - 12 years ago
Thanks Billy, Which link is broken? I just tried them all and they worked at least for me but I might have missed something obvious.by Bertho - General
Extruder Performance Measurements - 12 years ago
There are so many extruder designs, both drive and the hot-end, that are being proposed. How can the performance be measured? It is difficult to optimize a design if there is not a measurement procedure. To keep it simple, maybe something like: XYZ design can @220 C continuously extrude more than NN grams of PLA /second using a 0.4mm nozzle in the air (not printing) XYZ design can @220 C conby Bertho - Plastic Extruder Working Group
Extruder patent list - 12 years ago
Where can I find a list of existing extruder patents without spending too much time searching? We ought to have a list on the Wiki or somewhere. I do not want to create something that is patented. It is also educational to read the patents.by Bertho - Plastic Extruder Working Group
Re: Looking For A Bowden Extruders Update - 12 years ago
Here are the changes I made to upgrade the Bowden & drive system: Bowden upgrades Drive upgrade My next project is an improved extruder (hot end section) Berthoby Bertho - Plastic Extruder Working Group
Re: Thermocouple - 12 years ago
Here is a link to Thermocouple trouble shooting and heater measurements. I got tired of keep commenting so I wrote it up in one place. TC Info and troubleshooting Berthoby Bertho - General
Re: Stratasys's mojo : throw-away hotends - 12 years ago
Those crappy brushed motors typically have a specified life of 2000 hours life which is a lot of printing.:-) Unfortunately I did not want to take pictures of the inside of the print-head. They were getting suspicious of me taking all the pictures. Does anyone know where I can buy a Mojo print-head? Preferable a used one since I do not want the custom 1.3mm or so filament and pay the full pricby Bertho - General
Re: Extruder drive: steppers vs DC motors - 12 years ago
Thanks jcabrrer. Here is a review/comments about of the Mojo printer. It uses a small DC motor: Here is a first update from my visit to the Rapid 3D trade show in Atlanta, GA. I have been trying to understand the new Mojo FDM printer from Stratasys so it was one of my first stops. Following the usual trend, “low-cost” printer and custom ink, this model has taken it a step further: A caby Bertho - Reprappers
Extruder drive: steppers vs DC motors - 12 years ago
Steppers makes it simple to control the extrusion process but they are large and heavy. I have an Ultimaker and I am actively modify it. What 3-D printers are using DC motors? How are they controlled? Does some of the open source software use shaft encoders and PID control? Here is a link to my first upgrade of the Ultimaker: Thanks in advance, Berthoby Bertho - Reprappers
Re: Heated Bed Question - 13 years ago
I think the key issue about cracking is that the glass is without extra drilled holes. All the pictures that I have seen had cracks that passed through (originated at) the drilled holes.by Bertho - General
Re: 1.75mm Filament vs 3mm Filament - 13 years ago
The gearing and stepper setup is secondary regarding the required force. Just think about it as a hydraulic system: In one case the driving piston is 3mm, in the other case the piston is 1.75mm. The area is only 34% of the bigger filament so therefor the required force is also only 34% of the 3mm value. Berthoby Bertho - General
Re: Direct drive bowden? - 13 years ago
Thanks Sublime. Since I want good resolution it looks like geared is the waay to go.by Bertho - Plastic Extruder Working Group
Re: Direct drive bowden? - 13 years ago
I have been wondering about this too. Will not microstepping help this by a factor of 8 or 16?by Bertho - Plastic Extruder Working Group