First printer build

hello

I'm building my first 3d printer.

I'm using a arduino uno running teacup firmware

The question I had was regarding phase current for my stepper motors. How much current/torque do I really need for a printer?
The motors I found run at 4.4V and have per phase current draw of 2A resulting In holding power of 63 oz.
The drivers I found are: (Geeetech Stepper driver Pololu DRV8825 & heatsink for RAMPS1.4 Sanguinololu) they have a 2A max output and 1.5A output without cooling.

So would this setup be able to produce a decent 3d printer?

I know the torque depends on what kind of drive system I'm using, either a belt or screw but I'm not sure yet.

I'm also worried about being able to fit all four of the drivers on the Uno, but It's possible with easy drivers

Edited 2 time(s). Last edit at 01/22/2015 02:33PM by mrn26.

Quote
mrn26
hello

I'm building my first 3d printer.

I'm using a arduino uno running teacup firmware

The question I had was regarding phase current for my stepper motors. How much current/torque do I really need for a printer?
The motors I found run at 4.4V and have per phase current draw of 2A resulting In holding power of 63 oz.
The drivers I found are: (Geeetech Stepper driver Pololu DRV8825 & heatsink for RAMPS1.4 Sanguinololu) they have a 2A max output and 1.5A output without cooling.

So would this setup be able to produce a decent 3d printer?

I know the torque depends on what kind of drive system I'm using, either a belt or screw but I'm not sure yet.

I'm also worried about being able to fit all four of the drivers on the Uno, but It's possible with easy drivers

The Ramps will not fir on a UNO fullstop you will need an Arduino Mega 2560 for it and then it will do what you want but you will be pushing the drivers to the limit with that sort of current draw

I actually don't plan on using a ramps at all. I will just connect the drivers straight into the Uno

If I ran the drivers at 1.5 do you think they would be okay heat wise? They do come with heat sinks I can attach.

Well, the RAMPS or any dedicated shield/board makes things easy for few bocks ! Do you want to plug the heatbed and the heating resistor directly on the arduino too ? Add relays, home built stuf around your arduino and you will overtake the RAMPS price. Maybe you're an electronics engineer and you want that at purpose. IMHO, 63 oz.in is an average value.Anyway it's impossible do help you properly if we don't know about the machine itself. Architecture ? Transmission ? Print size ? How many extruders ?

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

I actually thought it would be easy, from the hat I saw around the Internet. But I am a newbie so who knows
The extruded heater and heat bed, I was thinking I could create some separate setup for that, since the just have to heat up and sit off at the correct temp. Or is that something that should be computer controlled?

As far as the setup of the printer, I'm leaning towards belt drives.
From what I've seen most printers use two motors for the z axis, have you seen a method that uses just one motor?
I just want one extruded, at least,for now.
The print size, at least 8x8, a foot would be nice, but I don't know how practical that is.
The actual frame I'm still designing.

Don't get me wrong, I don't want to say a newbie cannot design a fully functionnal printer. In most cases people missestimate their skills. Especially if they have no experience of 3D printing. I'm not a newbie on CNC engineering and even if my first printer was a kit, I had to face simultaneous printing problems on that meant to be functionnal machine. IMHO there's no need of reinvent the weel, especialy with electronics. The Ramps was engineered to make things simple and affordable. You're up to enjoy complicate the full process. Carthesian printers have two motors on the Z for many reasons. It prevents the X axis to run out of square and makes X axis leveling fast and easy. It solves a lot of problems for few extra bocks. IMHO you're on the wrong way, my advice is to read more about 3D printers, for all these things to make sens to you, or just build one well known functionnal printer, at last for your first experience.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

Quote
mrn26
[...]The extruded heater and heat bed, I was thinking I could create some separate setup for that, since the just have to heat up and sit off at the correct temp. Or is that something that should be computer controlled? [...]

I read, that sometimes it is pretty good to have the possibility to adjust both temperatures after the first 2-3 layers. So, yes, it would be advisable to have this option.

Zavasheir: okay I'll just buy another motor then, and save the trouble. Since the last post, I have decided to basically build a reprap.
I'm shocked at the prices of extrudes, do you know any way of building my own or will that cost more?

This guy created an Extruder out of a hot glue gun: [www.instructables.com]


Ano: okay, that is good to know.

If it worked well, we would both have one. Glue gun have no precision at all, fused glue is not stiff. Otherhand, it could be funny to change glue sticks each 20s For important printer parts, you don't want to do it cheap but you want components working first time, any time. That's why you cannot save that much on the extruder, surely one of the printer's most important part. A printed pastic part kit for the extruder cost about $18, a usable hotend starts about $16, and count $5 more for the hardware. if a friend/fablab can provide the plastic parts for less, don't expect to save more than 10-15% on the other extruder's parts. If you want to save money on your build, cut a mdf frame, dismantl and recycle old scanners/copy machines (endstops, rods, steppers), get your electronic boards in kit. But don't save on important components. My advice.

Edited 1 time(s). Last edit at 01/26/2015 04:38AM by Zavashier.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

mrn26,

I was where you are now about 2 1/2 years ago. I built a machine of my own design using a lot of surplus and scrapped machine parts. I went with off-the-shelf electronics (ATMega2560/RAMPS) because of all the support available in terms of software and other people's experience. You can do it. It is just going to take some time and focused effort. I made a LOT of mistakes along the way. You can see the evolution of my machine here: [mark.rehorst.com]

A few comments on machine architecture:

First and foremost, you can build a machine out of 3D printed plastic parts and toothpicks, and you might even get it to print once in a while, or you can decide to do it right from the start and make a machine that is sturdy and won't require adjustment every time you want to print something. I would avoid materials like laser cut plywood (flexes, warps, and delaminates), MDF (glorified cardboard), and anything that uses plastic parts in the structure of the machine. Look at a professional milling machine- do you see anything light weight about it? You can't get high precision results if your machine flexes. Go with aluminum- plates and extrusions. It's almost as easy to work as wood and will provide a stable foundation for your printer. If you're concerned about the expense, get to know your local scrap yard people (they usually like beer). I used scrap 8020 extrusions to build the frame of my machine for about 1/10th of the price for new extrusions. Scrappers can often provide motors, belts, pulleys, guide rails, bearings, etc, at very low cost.

If you're building a machine with a large build envelope, I'd recommend one of the architectures where the print bed moves only in the Z axis. Larg(ish) RepRap machines (like mine) end up with a lot of moving mass in the Y axis which requires reduced print speed or results in compromised print quality.

If you plan to print using ABS (a very strong, tough material), design the machine to be easily enclosed, exactly the opposite of what I did. If you try to print with ABS more than 50-100mm high, the print will delaminate unless you print inside a warm enclosure. It doesn't have to get hot, just 45C or so will prevent delamination. You'll probably need a heated bed, too.

Dual motors in the Z-axis: Don't do it. It's tempting because it is inexpensive, but use a single motor with a belt to drive the other end of the Z lifter instead. The idea that two motors makes it easy to adjust the X axis is true. What is also true is that it is easy for the two to get out of sync and you'll be adjusting the X-axis all the time, when you'd rather be printing. Using a single motor with a belt ensures that the X-axis remains exactly where it is supposed to be- you'll only have to adjust it once, when you set up the machine. The orthogonality of the axes is fundamental to having your prints come out as you designed them. If the axes are not orthogonal, squares won't be square and circles won't be round. If you print gears that aren't round they will bind. The relative position of the axes should be rigidly fixed and not allowed to move without some significant effort deliberately aimed at moving them.

Electronics: the AtMega2560/RAMPS combo is cheap but it is also pushing the limits of the processor to drive a 3D printer. A more modern solution, like the smoothieboard is a better choice for a number of reasons. First it is a lot easier to use mechanically- almost all the connections are brought to the edge of the board and connectorized. Second, all configuration variables are located in a single text file that gets loaded from a uSD card on the board every time the board boots up. With ATMega/RAMPS every time you want to change something you have to hunt for the appropriate variable among several configuration files, make the change, then recompile the firmware and squirt it into the board - it is a PITA. Third, the smoothieboard CPU is no where near its performance limit with 3D printing. That means features can easily be added for additional functionality and improved performance. There are about 100 other ways the smoothieboard is better- check their web site.

Autotramming: seems to be a hot topic these days. Autotramming is the software compensation for an unleveled/zeroed print bed. Autotramming is a lot like using two motors for the Z axis. It makes it easy to do something that should not have to be done at all, or only infrequently. Autotramming is a crutch for poor printer construction. If you build your printer so it is rigid, you won't need to adjust the bed level and zero every time you make a print. You don't have to overbuild your printer like I did to make it rigid. It can be made much lighter and simpler. Autotramming requires adding an inductive sensor (typically) to the extruder carriage, making it larger and heavier, both of which aren't good for print speed or quality and printer size.

Printer control software: for some reason a lot of people use software such as pronterface to drive their printers via a USB cable. Most printers/electronics for printers have the capability of printing from an SD card or USB memory stick plugged directly into the printer. I recommend you set your printer up that way. There are about 1000 ways a 3D print can fail. Adding a computer to the mix increases that to about 10,000. If you use a computer, your print may fail if the USB cable is bad, if someone tries to do something else on the computer while a print is running, if the computer decides to reboot for a "security update", if the computer decides to sleep, if the battery goes dead, if the power cord gets unplugged, if a kid or cat decide to type on the keyboard, if someone plugs something into one of the computer's USB ports, etc. If you choose an electronics package that can support an SD card, by all means get it and use it. You don't need printer control software running on a computer to drive your printer. Slicing software is getting better all the time and doing things like temperature adjustment at different layers can be done in the slicer so you don't need to do it from a computer while the printer is running. Also, you can make a lot of basic adjustments from an LCD/encoder panel if you feel you absolutely must make adjustments while the print is running.

Finally, seek out a makerspace in your community. They often have tools, materials, and expertise needed to help you achieve success in all your projects. I would not have been able to build my printer without the Milwaukee Makerspace.

Edited 3 time(s). Last edit at 01/26/2015 10:25AM by the_digital_dentist.

Wow! Thanks for all of that info. It really helped me allot.

I like the idea of using just one z motor and having it lift just the bed. I was worried one motor would not have the strength to lift the z axis by itself.
A smoothie board would be nice, but I am on a tight budget, so I think I will have to stick with the mega/ramps combo for now.
I think the mega has a SD package, which I would like to add later, but for right now I think I will use the computer. Again just for money reasons. I'm basically trying to go bare minimum, and then slowly upgrade later. But I really like the sd card idea.

I have always wondered about bed leveling, and never understood why it had to be leveled all the time. So what you said makes more sense.

I plan on using PLA just because it's not so toxic like abs. But I hope to later experiment with other "exotic" filaments, like rubber, wood, etc.

I also heard that you could desolve the material your printing with in acetone, and then spread some of it on the print bed, and it will keep the print from pulling up.

What is your opinion on motor strength, I'm looking at two different sets. The first being 60oz motors and the second being 50oz motors. The second set being about 10 bucks cheaper

Edited 1 time(s). Last edit at 01/26/2015 01:45PM by mrn26.

The digital dentist your printer represents one vision of what a good printer must be. In many ways you're right, and your philosophy about machines argues. It's easy to estimate the cost of your printer, it's realy not the same budget compare to $300 repraps. Compared to yours, some printers will print perfectly for a small part of your overall budget. Heavy structures needs powerfull motors and so on, with an expensive bill at the end.

IMHO; a 3D printer don't need to be as heavy as a CNC mill because it won't have to stand the same forces, like a laser by the way. There's some vibrations issues to manage, but nothing comparable to a CNC mill. In 3D printing velocity is important. Even with large servomotors you won't have the same velocity on a heavy machine. If you compare a real plane to a RC plane, both fly pretty well but the RC one accelerate and change direction faster, because of its dimensions and light weight. I totaly agree with you than ultralight components brings another issues. That's why a new machine design must be studied with a lot of calculations around speed and components. All must match together, neifher too much or too little.

According you may have the budget to build a machine like yours, you must have access to a pretty well equiped workshop and be skilled enough to manage the whole project. Don't you think the goal is too high for a beginer with maybe no print experience ? Designing a fully functionnal machine, that works first time, anytime, is an engineer team work. And it's a long way through. Maybe it's easyer to follow the BOM of a good reprap already engineered and working worldwide. What do you think ?

mrn26, the smoothieboard is certainly a good cart, but cost half the price of a regular reprap. Do you know about the MKS Gen ? It's a less expensive card ($46) using Marlin, like most of the repraps. It's an All In One card (arduino+Extended Ramps), with wiring facilities. Check it out

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

The MKS Gen would definatly be nice, but it's and extra 15 bucks witch I guess isn't that much. Is the MKS Gen basically just the ramps/mega put together on one board for simplicity? Or am I wrong?
Is the mega that under powered? It seems like a lot of people use it. I have heard of people burning up ramps though.

Well, if you buy good quality cards, it will cost you more than 15 extra bucks ! A regular Arduino Mega (not a chinese copy) will cost you at last $30. And a good Ramps $20. So the MKS Gen give you more for less bucks. On the MKS Gen, you have 2 extruder outputs implemented on board. No need to disconnect fans to install a second extruder like on a standard Ramps 1.4. You can power the whole board with 24v for better performance (aduino is limited to 12v). Each axis have one extra output which allows you to install extra driver board to pilot another synchronized motor :

This feature is realy interesting if you want to raise a bed with multiple motors for example. Or duplicate multiple production printers sharing the same board. The card uses a recoverable fuse too. All the remaining features are comparable to a regular Ramps.

To me, the most important feature on this board is you don't have slippy dupont connectors, but HX connectors which holds a tiny lock. Cable management is also easy because all the connectors are all distributed on the edge of the board. On the Ramps, you can't do anything than to have a dense spaghetti forest comming from everywhere. That does not help heat diffusion. If you need to, you can install a large heatsink over the alligned transistors. That's impossible on the Ramps because they're installed verticaly and perpendiculary. Last, the board is larger but also thinner. IMHO it's easier to install than a cubic stack of boards. Under the bed, for example.

With an arduino/ramps configuration, I've been printed a tray full of complex parts, at good speed (125), at 0.1mm resolution. It was up to 16 hours of print. I did not noticed any lagg or overheating. IMHO laggs comes from computer USB communication. When using the printer in stand alone mode (with an LCD controller or so) the print is fast and fluent.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

Quote
Zavashier
The digital dentist your printer represents one vision of what a good printer must be. In many ways you're right, and your philosophy about machines argues. It's easy to estimate the cost of your printer, it's realy not the same budget compare to $300 repraps. Compared to yours, some printers will print perfectly for a small part of your overall budget. Heavy structures needs powerfull motors and so on, with an expensive bill at the end.

IMHO; a 3D printer don't need to be as heavy as a CNC mill because it won't have to stand the same forces, like a laser by the way. There's some vibrations issues to manage, but nothing comparable to a CNC mill. In 3D printing velocity is important. Even with large servomotors you won't have the same velocity on a heavy machine. If you compare a real plane to a RC plane, both fly pretty well but the RC one accelerate and change direction faster, because of its dimensions and light weight. I totaly agree with you than ultralight components brings another issues. That's why a new machine design must be studied with a lot of calculations around speed and components. All must match together, neifher too much or too little.

According you may have the budget to build a machine like yours, you must have access to a pretty well equiped workshop and be skilled enough to manage the whole project. Don't you think the goal is too high for a beginer with maybe no print experience ? Designing a fully functionnal machine, that works first time, anytime, is an engineer team work. And it's a long way through. Maybe it's easyer to follow the BOM of a good reprap already engineered and working worldwide. What do you think ?

Though it is hard to do in a RepRap architecture, you can build a sturdy machine with very light weight moving parts. My goal in using the aluminum extrusions was to build a machine that wouldn't need frequent readjustment and wouldn't deteriorate over time with exposure to heat. Aluminum extrusions provide both, and if one is resourceful, can be obtained inexpensively. My machine is definitely over-built, and were I starting a design/build now, I'd use a different architecture that would not have the print bed moving in the Y-axis.

As far as beginner level difficulty goes, I was a complete beginner when I started designing/building my machine (with many mistakes made along the way, and corrected one by one). I did have access to a well-equipped workshop at the Makerspace, hence my suggestion that the OP find one local to him. While it may be easier to follow someone else's design and BOM, someone who is considering building such a machine probably has the imagination, motivation, and ability to recognize shortcomings and pursue a better result or they wouldn't consider building a machine in the first place.

I don't know what the OP's motivation is so I can't say whether he's better off with a 100% DIY approach or buying a kit or following someone else's designs. In my case, the kits and designs available when I started on my project were not satisfactory, so I chose to roll my own design. It certainly has not ended up any less expensive than buying one of the better kits, though the expense has been spread out over a couple years. You can ask what the printer costs, but you can't place a $ figure on the feeling of accomplishment that comes from doing it all yourself, learning as much as you do in the process, and knowing that your prints are as good as it gets, regardless of machine price.

Zavasheir: so the Chinese clones on eBay are bad products then?
Okay so I'm reading that people are having problems with drivers and such. This is the one I've been thinking of buying: [www.ebay.com]

Okay so here is another option this one is from sainsmart, I'm assuming they make legit mega and ramps clones? [www.sainsmart.com]
The only thing that bothered me was it says they updated the ATMega8U to the 16U. Will this cause compatibility issues with printer firmware, etc.?
I don't know, The MKS would save the headache maybe I'll just do that.
Will DRV8825's work with the MKS Gen?
Also where would be the best place to purchase the board from? Aliexpress has it for $45 but bang good has it for $39. Are there cheap clones of the board that I need to look out
for?

Also is it okay to buy stepper drivers on eBay? From China? I found these: [www.ebay.com]

Lots of questions

Dentist: I also want the experiance of complete building from scratch.

Edited 4 time(s). Last edit at 01/27/2015 01:15PM by mrn26.

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mrn26
Zavasheir: so the Chinese clones on eBay are bad products then?

Hmmm. Very difficult question. Says it depends under which star you're born. Sometimes the cheapest works as good as the expensive ones, sometimes no. There's great chinese brands too : Leadshine, for example.

I can't see your ebay link : country restrictions.

For the MKS Gen, try the engineer/manufacturer : [www.makerbase.com.cn] A4988 and DRV8825 are compatible, even on the MKS Gen.
If you want the best drivers, buy them directly at pololu's. Some drivers provided with my kit was broken, I bought some cheapest ones in hurry and they still works. I have also 15 cheap A4988 working elsewhere too. If one of your driver does not work; the seller will refund you or will replace the damaged without arguing anyway.

Edited 1 time(s). Last edit at 01/27/2015 02:09PM by Zavashier.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

So I found the maker are store but the MKS Gen they offer, has intergrated drivers, which is fine but they are the A4988's which are only 1amp which wouldn't work for my motors.
However I also noticed they offer a traditional ramps/mega combo (mega with ramps shield) for $30 and then they have 5pc set ofDRV8825's for $10.

What I don't like is the 15-25 day shipping plus 6 day processing. I guess that would give me time to build the frame of the printer.

Edited 1 time(s). Last edit at 01/28/2015 12:59PM by mrn26.