HM version 4 Rpi 3d print case


 
Matt,
I have been running Turbo CNC, but I can run Mach3 it support my board as well. It is a 4-axis board, I just never used the fourth axis. It is the 4-axis version of this board: http://www.hobbycnc.com/products/hobbycnc-pro-chopper-driver-board-kits/

It is called a 7th Sojourn and you can see it at the very beginning of this video: https://www.youtube.com/watch?v=19wVS0ad4ec

I built it off plans I purchased. Works pretty well.

dave

M Miller said:
Dave,

are you running mach3? Do you have a 3 or 4 axis BOB? If you've got a 4-axis BOB you're in luck.

Can you take a pic of your CNC? I've been joensing to get a CNC table for a while now.
Matt
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I've been looking around for a better deal/better printer than the MakerFarm Prusa i3 and I really haven't found anything that looks better or cheaper, so I think I am ready to pull the trigger on the 8" Prusa. The only option I need to decide is which nozzle to choose, .35mm or .5mm? I think I read somewhere that the first nozzle you work with should be a .5mm, but I am wondering why? What are the advantages or disadvantages of the larger or smaller nozzles? Also, I am wondering if there is any reason to choose a metric over standard thread design or vice versa?
Thanks in advance for your input...
PS in my searching I have seen people printing items like vases, soup bowls and coffee cups with ABS plastic, they seemed to be holding liquid, and hot liquid at that... Makes me wonder why that is holding liquid but I was told 3D prints arent really water proof? Are you guys using ABS or PLA stock to print with?
 
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0.5 will be slightly easier to print with until you get the hang of it. As scientific as 3d printing is, there is quite a bit of "art" to it. Plus, you can easily buy a 0.35 nozzle and interchange them as you wish.

You can make watertight objects with a 3d printer, it all depends on your design, print settings, etc.

I use abs exclusively.
 
Waterproofness really depends on the print, specifically how squished is the first layer? are there enough solid layers to provide a watertight base? Are there enough perimeters? Even though those objects look like they're holding water or other liquid they can let liquid into the center of the part. It's difficult to explain. :( Basically you can produce watertight parts, but you cannot guarantee that those parts won't allow water to pass through microscopic wall or layer defects. But for 'good enough' then yes you can print water-tight parts. Just don't expect it to be truly waterproof. Water will eventually find a way...

0.5 nozzles are way easier and are more forgiving, especially for the critical first layer. Plus you'll be able to print objects faster using thicker layers. Small features won't be as crisp as a 0.35 nozzle, but to start out I would really go with the 0.5.

You want metric rods on your Z-axis. It's a technical reason for this (whole steps per mm) which will allow you to choose many more layer heights than standard rods. If you'd like a detailed (and boring) explanation I'd be happy to do so. Basically standard rods introduce error which translates into printing artifacts in the object. No bueno.

And Tom is right - there is a certain amount of voodoo in 3D printing. Sometimes things inexplicably go wrong, and sometimes things go way better than planned.
 
OK, you guys convinced me to go with the .5mm nozzle, and for some reason I knew I should ask "standard or metric?", glad I did! :) It seems I have just about all the questions answered, only thing I need now is a Discount Code for Maker Farm! :confused: Seems they've gone up $15 on the 8" i3 while I was procrastinating....
 
RalphTrimble said:
Seems they've gone up $15 on the 8" i3 while I was procrastinating....
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If you buy 5 you can get them for only $495! The price did go up by $15 but their spools of filament went down by $3 each so you can make it up if you buy a 11lbs of plastic, right? I'm still waiting on my kit to ship.
 
I'm taking some time to get familiarized with Autodesk 123d and was going to mess around with the 3D case from github. However the current 123d file is too big to download raw, and I'd rather not pull the whole repository just to get a single file. Any chance you can host that somewhere?
 
Bryan Mayland said:
I'm taking some time to get familiarized with Autodesk 123d and was going to mess around with the 3D case from github. However the current 123d file is too big to download raw, and I'd rather not pull the whole repository just to get a single file. Any chance you can host that somewhere?
Click to expand...

Bryan, here is the latest version I have with a few tweaks after printing the case a couple of times.

https://docs.google.com/file/d/0B1qMo4bilbhhcDcxUngyRFZSTE0/edit?usp=sharing

This version is made for 30 mm M3 screws
 
I assume you're using 123D Beta 9 or is there something better. I've been trying to get 123D Design to open a 123d file for half an hour now with no luck. They say "legacy 123d files are supported" but I think they're full of it. 123D Design is a super dumbed-down version which just gives you the essentials and is designed to be used even from a web interface or an iPad.

I know I'd downloaded 123D Beta 9 so I gotta see if I still have it. This new version is for children.

EDIT: 123d beta9 download
 
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I did the same thing at first, got the other non beta version, it didn't load up right for me for some reason (didn't seem to work properly) I re-read your post and found the beta version, uninstalled the other version and installed the beta and I was up and running....
I've only done a little poking around, figured out a few things though. The interface design is foreign to me and will take some getting used to. I've done quite a bit of work with Corel Draw (2D) and kinda wish I had a 3D version of that, cause I am pretty efficient with it already... I know they got one, but it's pricey... I wonder if it can make the types of files the printer needs? (Perhaps my Corel suite came with a 3D app I didn't install, I'll have to look).
What type(s) of files can the reprap type 3D printers (Prusa i3/mendel) print anyways? Haven't got my kit yet and didn't run across any details about file types so far in my reading...
 
The firmware you install dictates what file format they take but as a standard almost every printer print G-Code I think. To get G-Code you need to use a program like Slic3r or Pronterface, which usually takes STL files. STL files can be "saved as" from 123D.

I'm used to SketchUp's way of doing modeling and this is still pretty frustrating to learn. I've spent half my day trying to model an object I have here and haven't gotten the basic shape yet. It doesn't help that Sketchup's orbit mode is the reverse of 123D's.
 
There are lots of steps involved with setting up and printing from a 3d printer. I will briefly list them as I see them. Matt may have a different opinion.

1. Assemble printer. Should be easy for you guys since you have a kit. Read about the build in advance. Have all of your parts sorted and the necessary tools.

2. Make sure your axes are square. You will never get a decent print if your axes are not perfectly orthogonal.

3. Calibrate. You need to carefully calibrate the machine so that the firmware can translate mm into motor steps. I would read more about this and use this tool to help you:
http://calculator.josefprusa.cz

4. Choose your firmware. There are several different ones. I prefer sprinter/marlin but you can check out teacup, repetier, etc. Once you have your firmware chosen, update your config.h file to reflect your calibration settings. This is also where you can play with acceleration settings to tweak your print quality. Test your calculated calibration settings and adjust as necessary.

5. Choose your host software. I like printerface but I've never tried anything else. A lot of people like repetier too.

6. Convert your 3d sketches to gcode. I usually save a copy of my 123d files as .stl files and then run through a program called netfabb to check for any errors. I then slice (convert to gcode) using slic3r. There is an excellent tutorial here:

http://richrap.blogspot.com/2012/01/slic3r-is-nicer-part-1-settings-and.html

You can also try skeinforge but I don't care for it.

7. Keep tweaking

I would start by printing the calibration stl files that you can find all over the internet until you are happy with your prints. There are so many settings to tweak between the firmware and the slicing software that you can literally write a book about it. Just follow basic experimental principles and isolate one variable at a time. I can assure you that you will never stop adjusting settings because you continuously find new ways to isolate subtle imperfections in your prints that, if you are as OCD as I am, will keep you up at night.
 
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Thanks for taking the time to lay that out for me. I will be doing more reading in the coming days and hope the printer kit comes next week...
 
Bryan, I am wondering if MakerFarm has shipped your printer kit yet? Mine was supposed to ship by tomorrow or sooner, so far no ship... So much for the "or sooner" part, I just hope they are able to ship on time tomorrow. I know you ordered a day or two ahead of me, so yours should be on its way.....
 
Yeah they shipped mine a week after I ordered it. Ordered Friday May 31st, Shipped Friday June 7th. So they were right on with the "one week lead time". I hope to have it before next weekend so I can try to build it, fail miserably and have end up being a sentient robot who is ashamed he can not perform the purpose he was built for. So he sobs endless extruded plastic tears.
 
Glad to hear they shipped yours on schedule with just a week lead time, hopefully that means mine will ship out tomorrow. I'm anticipating a similar river of plastic tears in my basement next weekend as well... LOL
 
Today is the day my printer is supposed to ship, so far their website still says "Processing"...

Last night I made some progress figuring out how to use 123D(beta), right now I am designing my first 3D project which will be a HeaterMeter blower adapter. This has brought up some basic questions about the printer capabilities:

1) What is the resolution of the prints? (.5 hot end) In making my design I have some leeway to make things bigger/smaller, whatever is best for the printer. For instance, if I have a block that is 15mm wide, with a 10mm hole in it at the center, there will be 2.5mm remaining on each side. Will the .5mm be an issue, if so I could make the block 16mm wide leaving 3mm on each side instead. (or whatever suites the printer resolution best)

2) If I am making a hollow box, how thick do I need to make the walls so they will be strong enough to support themselves and be reasonably solid? Lets say you have a 60mm hollow cube, what is a good thickness to make the walls to get a fairly rugged object?

I figured I should ask these questions here while I am designing rather than design and just print and hope....

EDIT:

ALSO....
I was looking for a pre-made gear design to use in my project, but find the 123D gallery lacking gears, search only returned two results. Is there a better place to find pre-made 3D models? What I am looking for is a small gear that when rotated will move another object in a linear motion. So I am looking for a design with one round gear and another flat object with linear teeth that mesh with the round gear.

Double EDIT: LOL
Thinking about my design, and limiting the number of (moving) parts, I have come to the conclusion I could use a tapered screw to accomplish the same goal as the above gear for linear motion. So I guess I dont need those gears (right now) but I would still appreciate links to repositories where I can find various 3D part designs...

At this point in my venture I have to decide if I want to learn how to design and print gears or threads? Which would you guys choose? (light duty requirement for this part, it will meet no resistance to motion)
 
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