I have just uploaded a 3D printer specifically designed for the GRABCAD community.
This is the best printer I have designed to date.
CNC design Architecture,
300x300x400mm build area,
Incredibly precise, strong, and stable design.
Just my way of saying thanks to the GRABCAD Community. from Xgentec Jason
I had a look at it, it is a reinforced copy of Creality which also eliminates the long gap in filament push by adopting the close to extruder feeder solution (you might also use the extruder-feeder in one piece solution available on-line premanufactured for like 30 euro)
I just assemble my FLSUN Creality 300x300x400 not installed the software yet. My complaints were exactly the feebleness, the long gap from feeder to extruder that makes impossible to print with flexible filament and the fact that the end of the two threaded rods for vertical travel have no centering bearings at the opposite end of the steppers. I plan to print that myself out of my design to correct the design flaws.
Another issue is just like your redesign, the FLSUN CREALITY has no ducted air piece for the extruder fan so that the air blown to the extruder cooling aluminum piece be re directed the air to also pass over the printed surface to help cooling faster the printed layer. I plan to print that myself out of my design to correct the design flaws.
Also the horizontal movements (both of the extruder head and of the flatbed are on belts) when it would be easy to make them on threaded stud like the verticals. I plan to print that myself out of my design to correct the design flaws.
Next thing I may make a 1 cubic meter printer with fixed printing bed, gantry moving system in all directions, maybe in a year, where I will try to use at least 10 extruders in concomitance, my headache is the slicing interlacyng and concomitance printing with more than one material at the time (like soluble PVA for supports and other materials for the final piece.), or in poor words, the damn software.
I actually got my design principle for this from CNC milling machines. CNC technology has been around much longer than 3D printers.
I did consider a XY axis screw rail but on my previous printer Trident it causes squeaking and severely sacrifices print speed.
This printer is designed for print precision and fast print speed. Fast print speed is something screw rails lack and cheap screw rails are prone to reverse jamming at high speed and squeaking when mounted in horizontal unless you use very expensive professional screw rod and lead screws. Good screw rails and lead screws are very expensive and very heavy. The heavier the X axis and extruder means the more severe the nozzle wobble at higher speeds destroying print quality. This is a mistake many designers make not taking in to account velocity, mass and gravitational force of moving objects.
This printer also solves all issues of frustrating bed leveling I have had on all my printers. This is much less time consuming to set up. Also solves the issue of filament lag with the center mounted bowden extruder. The bowden is also easy to set up for both conventional and flexible filament.
Print fans are a personal preference but this seems to print better than any printer I have owned before.
Thanks for the comment Emil much appreciated. regards Jason
the solution to squeak is simple, grease, the solution to high speed accuracy and repetitive the same, actuators not steppers, and the solution to alignment is self alignment...
Loads of grease on cheap 3D printer screw rails is not really a good look Emil especially after time. Adding grease does not stop lead screw jamming at high speed direction reversals. Screw rails add weight to the X axis so when doing large prints this adds weight to the top end of the Z towers as they rise. The more weight on the top end of the z towers the more wobble at the nozzle tip as they get higher. There is no way around the physics it is the same as swinging flail weapon the more weight on the chain ball the more wobble. Then you have to address the backlash problem with screw rails adding even more weight to the x axis.
Screw rails are an excellent idea for moving heavy objects slowly such as milling machines etc... but belts are more suited to high speed fast changes in direction.
Also heat bed self alignment is an upgrade option like print fans. They just add an unnecessary cost and more complication in setup for beginners.
I am not sure how you plan on using actuators without steppers ? how will you control the accuracy with DC actuators ?
Not Stepper ? What then ?
I see you are referring to a linear rail motor. These are usually incredibly heavy and expensive, I have seen these on many big CNC milling machines and they are very good at precision high torque low and medium speed.
If you can find a linear rail motor option where the price, weight, and speed is better than a stepper motor and a belt drive then it could be a good option. I have never come across one before but it does not mean one does not exist.
Other cylinder linear motors are all DC motors and Steppers as far as I am aware.
What works best works best, physics always throws them curve balls, good luck with your project Emil.
Would be far superior to use linear rails instead of wheels on alu extrusions, these are often not close to straight!
You should have used a belted driven Z axis with a couple of linear rails, would remove any ghosting which almost certainly will appear if not using super expensive lead screws.
If cost, time, weight, size, electronics, RND, and hardware was without any limitations I would design an incredibly far superior 3D printer with a completely different printing method. However the design approach with this printer was portability, maximize print quality, keeping a high design quality while reducing and keeping cost as low as possible and keeping it easy as possible for beginners to build.
People keep using the word linear rails when it covers a huge variety of rail types.
Proper lead screws can be quite costly as well, the two apporaches are similar for cost, protability and level of design quality.
For print quality you remove the need for expensive lead screws, ghosting and wobble. Same resolution can easily be done with a gear.
Linear rails as in MGN9 or MGN12 rails, the most common types for 3D printers. Wasn't that relatively obvious? In case you were wondering https://www.google.no/search?q=linear+rails&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjgr_mo5-_cAhVJLFAKHZl5ADwQ_AUICigB
I am not sure where you buy your CNC profile but my 20x40mm stock seems rigid and certainly straight.
Just done a quick x axis cost variation analysis: Off shelf prices;
CNC extrusion profile 40x20 350mm £7.50 V wheels x 4 £5 VMount plate £0.50
Total : £13.00
MG9 Linear rail 350mm £13.40 Alum Box Section back plate 25x350mm £9.99
Total : £23.39
This is nearly double the cost I would not call this a similar price however I may make one give it a try for a future design.
Might be double in money per part price, but it would not double the price of the end product, maybe raise it by 50%, which still keeps the end product within the range of affordability while delivering a far better machine, my 2 cents.
Agreed! Depends on where you get the components too!
Well I have heard a lot of theoretical opinions flying around x y axis screw rails, z axis belt drives? , linear rail motors, print fans, bed leveling. When are we going to actually see this machine or is it all hot air ?
How many real world printers have you designed and made. ?
No need to get defensive, this is a community and we're just pointing out ways to improve it. If you wanted blind praise, go tell someone who doesn't understand tech.
All of those things you mentioned exist all over the place. Especially print fans and bed leveling is basically standard.
Started 3, finshing the first one that will help me print to finish the second one, most expensive part will be a 3 000 \usd sintering oven with internal volume 300x300x400, to help me sinter the metal prints.
Frederic - Emil
My apologies if my message appears defensive. Blowing hot air is an engineering term for untried and untested where I am from. Was not intended as defensive.
As I said I have heard a lot of theories. ?
I was simply determining if you have designed or tested your design theories or if you are planning to.
I don't want to waste money and resources trying unproven theories when there is physical proof out there with your designs.
It would be good to see your CAD designs and printers are you uploading them ?
Started 3 that' s cool I will keep an eye out for your printers Emil.
I will be testing the linear rails in any case.
My apology if my previous message came across as defensive.
As I mentioned to Frederic I don't want to waste money and resources trying unproven theories when there is physical proof out there with your designs.
Actually one of them is a former EDM machine who´s railings are formidable, I plan to turn it in a printer with the bed 300x400 (original size) but using the neck long height as printing height that gives me some e 1800 mm tall print possibility.
I will not use steppers on it but servo motors, more expensive but far more accurate.
So I have the mechanics, need to put in the electrics, electronics and the damn software, my eternal problem... not a coder myself.
That EDM machine sounds like an exciting project Emil.
Servo motors are awesome I really like them, it is a shame they are such a high price. I will keep an eye out for your future projects Emil.
I will order a linear rail today to experiment with, make an x axis with extrude mount see how it turns out.
Thats awesome! Servo motors would be perfect for a 3D printer, too bad they're so expensive! :)
from a certain range of power up, price of good steppers are similar with price of servo motors. And to move the rails of this EDM it takes a bit of power.
Something on the tune but smaller and the horizontal axis are manual, just descending head is with a servomotor, need 3 more to move the arms and on more to move up and down the printing bed so that the printed piece sinks into the machine body where now is the EDM power plant, to be gutted.
Come on Frederic show us your printer designs.
I haven't gone and upset you now have I ?
That was not my intention.
That is a beast Emil. Beautiful and very expensive machine that.
Someone has converted a large milling machine on youtube with a detachable extruder attachment. Made a big solid detachable heat bed and everything.
It actually prints ok.
Haha, no you haven't!
I'll be sharing one soon, just touching up and updating components to match the fixes I've done since version one.
it should print better than OK, the body is solid, not wobbly, the railings are smooth, flawless and extremely precise, those machines were designed to stand far bigger stress and vibrations than in printing.
I got mine for free, a university was putting it in the skip. Right time in the right place, I asked for it and they gladly loaded it in my van.
Ah that's all good, I will keep an eye out for your printer design work in the future.
I have purchased an MG12 just to try out for now anyway and I have got much studying to catch up with.