Reprap Project

[Brokkr]

I am building a 3d printer as a tool for metal working and casting. I plan to do lost PLA/ABS casting by using 3d prints as an investment for a negative mold. I am a hobbyist and am trying to do this in the most cost effective manner. I am building my printer chassis out of 1.5x1.5 aluminum T-slot extrusions. The body itself is not a challenge, but the linear bearings are ridiculously expensive. For anyone who does not know, they are c channel aluminum that has been machined out to allow for mounting points on the outside. On the inner walls of the c channel they mount the same material as a kitchen cutting board. It is a “self lubricating” plastic that allows for smooth movement without bearings. I have done very limited searching on Thingiverse for any open source parts that would help me avoid paying 100 dollars per side of my z axis to get solid reproducibility. I have been researching ​_V Track_​ systems as well. They are all 3d printed wheels that ride along the outer diameter of the track and can be attached to a 3d printed ABS mount. If ANYONE has built one of these themselves or has printed parts please let me know. I would love to place an order on here as well as to get some feedback.

A few disclaimers, yes, I am a tinkerer and a hobbyist. I built my own metal melting foundry and do welding and a few other things. I know what building your own printer entails and I am not daunted in the least by the challenge. I appreciate your concern, but it is not relevant to my line of questioning so please don’t waste any space below to warn me about things I already know. I have put three months of sitting behind a keyboard looking at price points, kits, DIY, youtube, reprap, prusa, you get the idea. I am extremely excited about this project! I am going to include a pretty extensive list of links so you get an idea of where I am as of now and what parts I am looking at having reproduced. I have never worked with a 3d printing service before, however, I do realise the cost of doing business. I’m looking to cut costs from 300 dollars for mounts and plates to around 100-125 by having them 3d printed. I am in no hurry here guys. Thank you for your time and I appreciate you reading this far. Now for the links:

1 motor mounts for NEMA 17 http://www.amazon.com/Anycubic-Mounting-Bracket-Stepper-Motor/dp/B0154MHW1S/ref=sr\_1\_3?ie=UTF8&qid=1457632023&sr=8-3&keywords=nema+17+motor+mounts

2 t slot linear slide bearings I found these from the same guys I bought my extrusions from, these are a polyurethane part, most likely injection molded but I am not sure. They are crazy expensive and I will be needing two of these for the 1.5x1.5 extrusions. These are not made with the cutting board material mentioned above, just found them http://www.amazon.com/Faztek-Double-Flange-Bearing-Extrusions/dp/B008MQ9WUS/ref=sr\_1\_3?ie=UTF8&qid=1457632575&sr=8-3&keywords=t+slot+linear+bearing

3 I am planning on keeping the gantry weight down by using a stepper motor on top of the entire assembly and feeding the filament through a tube down to the hot end. I forge the name for the type of set up, but I need a mount for the top stepper motor as well.

4 I will need an enclosure for the linear bearings that roll along the 8mm chrome rod. This link is to the thingaverse page a gentlemen put up. He uses the exact same build I have envisioned, I only wish I had found his page earlier! Would have saved me a ton of time in materials research. Again, I am inexperienced with thingiverse so if everything you need is there then please let me know. I am Not sure of the size he used for the extrusions. Profabb GATE LE - 3D printer from U-Design by dvjcodec - Thingiverse

5 These are the wheels I referred to that ride along the “V” shaped channel along the outer diameter of the channel. I would prefer these for the linear motion as I fear that even ABS will wear out with the contact slides sold on amazon. Profabb GATE LE - 3D printer from U-Design by dvjcodec - Thingiverse

If you have any other questions or need info please let me know. I will be here to check things out daily at noon. Appreciate any input guys, thank you

Brokkr

[RCole]

For lost wax/material style you should look at MoldLay: http://3dprintingindustry.com/2015/02/16/industrial-manufacturing-desktop-new-moldlay-3d-printing-filament/

Good luck on the printer build. Get us some pictures as you get it up and running. Sounds like an interesting project.

[karlzhao314]

Hi Brokkr! I have a fair bit of experience in RepRap and might be able to provide some info.

(wall of text incoming)

I’d recommend taking a serious look at OpenBuilds V-slots as opposed to T-slot bushings (I don’t know if they’re the same ones that you were looking at, since your last link is a duplicate of your third). They come only in metric, but should cost a lot less for both the extrusion and each bearing plate.

OpenBuilds

Mini V Gantry Plate

A lot of the parts are also printable, further reducing your costs.

(To be entirely honest I’d seriously recommend trying to keep as many things as you can in Metric, even if you’re American like me and have always used imperial before. Metric is just more friendly in the world of 3D printers, since so many past developments were in metric.)

If you must use the extrusions from Faztek, you could try finding a hub that has Igus material and having them print bushings for you. They should cost significantly less than buying commercial bushings, though that depends on the hub’s pricing.

There’s really no need to buy commercial parts that can be printed, such as motor mounts or even extrusion brackets. My aluminum extrusion printer had printed plates and brackets for nearly every joint and mount, and because 3D printers are under so little stress (relatively), having so many printed parts doesn’t make much of a difference at all.

The system you’re thinking of for the extruder is called a Bowden extruder. There are plenty of excellent designs that usually integrate the motor mount. Here’s the one I use:

Super Bernis simple MK8 bowden extruder by MauricioNeto

Of course, I’m not in any way saying this one is better than the numerous others. Search “bowden extruder” and find one that fits your needs the best.

Finally, the 8mm bearing enclosure. Whether or not an existing design will work depends on how far apart your rods are. If you’re lucky or you design your printer to fit existing standards, a Prusa i3 carriage (of which there are many) could work pretty well. If not, unless you’re extremely lucky you’d likely have to either design a mount yourself or find a hub to do so for you.

I hope I helped a bit!

-Karl Zhao

[Brokkr]

Perfect wall of information! I will be going with open builds. I had used the V slot and T slot synonymously not knowing that regular aluminum extrusions were not notched. Would you be open to place an order with for my parts since you are so helpful thus far? Also, I will be using the 20x40 for everything just to maintain that line of reasoning for rigidity

[Brokkr]

Thanks man! I appreciate that. Wax is a great investment medium but I’m afraid I’m better with Google sketch up and the other programs than my hands ha ha. I’ll motley be doing lost pla but I will surely get some pictures up for you guys as the thread evolves. That stuff is pretty great with the low melting point. I’ll order some and give you some side by side comparisons in that and pla to know if it is as good as it claims or any different.

[karlzhao314]

Just to further clarify, technically all of the extrusions in question qualify as T-slot extrusions since T-slot just means they have a channel down each side for T-slot nuts. The V-slot extrusions still count as T-slots, but are just a bit different because of the V-shaped channel. So, you’re not wrong.

Of course I’d be open for an order, but do remember that you’re across the country from me. It might be better to support your local hubs rather than going out of your way to order from me.

20x40 should be fine. OpenBuilds offers V-slot in that configuration. However, if there are extrusions that don’t need to be extrusion, you should take a look at misumi-ec.com since they offer custom-cut lengths of standard extrusion for extremely cheap prices. (Ultimately it would be up to you to decide whether buying from one or buying from both would be cheaper, factoring in shipping.)

Good luck with your build!

-Karl Zhao

[Brokkr]

Supporting locally is a great aspiration but I also believe there is something to be said for being first to help out. Even if you are not here in Houston you still took the time to share your knowledge and that is important to me. I have decided to go for a C boy configuration, and would like to see if you can do this:

C-Bot

if so, I will place my order and get a price quote.

[karlzhao314]

Well, if you’re sure, I’d be open for an order. I’ve looked at all of the files for a C-bot and they look fairly simple to print.

However, a few considerations:

1. The entire C-bot package is a massive order. I can’t really give an estimate of my prices or the shipping I’d have to charge until I have a quote, and it could easily be more than you’re willing to spend. (Of course, if you do submit an order and decide it’s too much, I’d be happy to help you cancel the order.)

2. I’m currently printing another rather large order, so I can’t speak for how fast I’ll be able to complete your print. It could be two weeks, and it could just as easily be two months.

Are you sure you’d like to order from me? If you are, I’d be happy to print for you, but if you don’t, I won’t be disappointed if you back out.

-Karl Zhao

[Brokkr]

Quick update for anyone wondering, aluminum extrusions arrived and have been cut. Waiting on ramps and ARDUINO to get here as of today. Build plate is here and is a wonderful cut of 1/8" thick 600x600mm aluminum. I have made a contact with a printer for a few printed parts. The individual actually had a rather large build area to work with already. This made everything easier to really push the build envelope. Especially in the case of my y chassis for that big plate. I will be posting pictures as things come through. It is looking like I will have everything printed and be assembling a more complete frame by Monday of next week. I would gladly take photos but there is just not much to show at this point.

[Brokkr]

Getting a mock up done here just for a good visual. V slot makes this so simple: the hardest part has been waiting. All motors are wired and ready to run as soon as my mounting hardware and lead screws get here. Messed with ARDUINO and Repetier last night to fake a print and had all axis and extruder moving at once as if the print were happening. Z axis only moved when a layer finished and the extruder seemed smooth. The motion of the x and y was snappy as well