New ORD Bot Hadron build (ATI kit)

[madmike8]

Congrats! Looks like it's printing well!

[fulg]

Thanks! One issue that came up while calibrating is that the belts provided by ATI are in fact MXL, but I was told they were GT2 before I ordered. I wasn't sure at first but after looking in Misumi's catalog, I definitely don't have GT2 belts; my teeth are square. I ordered 2 meters of GT2 belts and new pulleys, so I'll get to use your belt clamps after all.

Another issue is that the Y carriage is hard to keep lined up properly (horizontally). While applying pressure on it while leveling the bed, I can affect the height on the left/right edge by half a millimeter, presumably because the delrin wheels are compressing a bit. This also means I need to redo the bed leveling until I get it straight. I adjusted the wheels with eccentric spacers until the platform wasn't wobbly and the movement was smooth, but maybe the wheels actually need to "bite" a bit more in the v-rails?

Plenty of small details to fix...

Cheers,
Ben.

[fulg]

I have received the GT2 belts and can visually confirm that what I had wasn't GT2 at all. The pulleys looked quite similar however so I think the kit (as delivered by ATI) has MXL belts but GT2 pulleys. That might explain some of the backlash I was seeing earlier. I'm currently printing the X-axis upgrades and madmike8's belt clips so I can change everything in one go once I find some time to dismantle the printer...

So far it has been a constant battle with bed leveling. I have to redo bed calibration at least every day, to compensate for variations on the order of +/- 0.3mm, not always at the same spot. It's possible my extruder/hotend isn't secured properly to the X-carriage. I am using the mount that was posted here because it doesn't require me drill new holes in the carriage, it reuses the existing endstop and belt clamp holes. I don't have access to a press drill so it's always a pain to poke new holes through aluminium plates.

I have moved the v-wheels even closer to the extrusion rails (via the eccentric spacer). Previously I only made them clear any gaps until there is no backlash, but now they actually apply pressure on the rail (trying to turn them by hand once installed will move the corresponding carriage instead of slipping). Not sure yet if this is better, or if I'm slowly ruining the wheels.

I have also discovered that my aluminium build plate is not flat. This explains a lot of the bed adhesion problems I'm seeing with larger prints. I can either get the center of the plate *or* the corners, not both. Again the variation is around 0.1mm, which is enough to ruin the first layer of any big prints (anything larger than a quarter of the build plate). I am replacing it with the usual borosilicate glass panel from a local supplier.

As I mentioned in another post, I have given up on the Azteeg X5. It is a great board hardware-wise, but support from the Smoothie team is practically non-existant. Issues are reported, discussed and resolved mostly on IRC, so no searchable record of solutions exist. The documentation is great but when things are broken you are left on your own to debug them. Lots of little things don't work right, it still has an "alpha" feel. Main problem for me is the lack of a functional autolevel (the code is there but it doesn't work). I don't want to be the guinea pig anymore, so I decided to go back to the same base hardware that everyone else has. My new Azteeg X3 should arrive shortly... I got some of those new TMC2100 drivers that should also give me silent stepper operation, which was the main selling point for me on the X5 (in addition to the easier configuration).

On the upside, I guess I have my controller for my next delta printer...

Cheers,
Ben.

[fulg]

So after a bit of a hiatus, I am back at this again. I am still stuck at the calibration phase, but yesterday I found out why I always had to manually level the buildplate all the time. It turns out that all of my V-Wheels have a slightly enlarged spacer, so I can shift the wheel on the bearing by about 0.25mm by pressing on it. This isn't so bad for the X and Z axes, but it is absolutely devastating on the Y axis. If one of the wheels slid by 0.25mm, with the build plate size, you end up being off by several millimeters on the edges.

This wasn't apparent when I built the frame, but as I kept rechecking everything, I noticed that the wheel bearings could "click" to one side or another by pushing on them. When taking apart the wheels, the shim is 0.9mm thick. Judging from the v-wheel tech drawing, I believe the proper thickness should be closer to 0.55mm. I will see once I get the new wheels...

Cheers,
Ben.

[PrintThings]

Hey Ben,

I'm another Canadian who built an ATI hadron, almost a year ago now.

I've learned a few things about the bed level. First thing, it's so much easier with your endstop at the top of the Z axis rather than the bottom, even with some kind of screw adjuster, it's just not as good. It's so much easier (for me anyway) to just adjust the Z offset in slic3r by 0mm-0.3mm, which will change depending on the ambient temperature from expansion/contraction.

Next thing is to have your ordbot on a level surface to begin with, and don't move it, not even an inch.

I check my bed for level before I use the printer, but it's been level for months now, no readjustment needed. I just do the paper check to see where to set the Z offset. If it's cold it'll be 0.3mm, if it's warm it'll be 0.0mm.

The ATI kid leaves some quality to be desired though, sucks you got bummed wheels. I had an extrusion with a bad dent in the V. They replaced it for me and the service was good, but I wish I had gone with a slightly more expensive and higher quality mechanical kit. The extrusions were also cut on slight angles, so I had to square up the ends. Pretty basic stuff to get wrong.

Good luck with your printer. They seem to have a bit of a personality, keep melting spools and you'll get it all figured out pretty soon.

[fulg]

It's been a couple of weeks since I installed the new V-wheels, and it completely solved my biggest gripe with the machine, namely the constant bed leveling. Now I only have to re-level the bed if I physically change something on the Z axis (i.e. adding PET tape or fixing the Z rods). What also helped is that I now use a feeler gauge to level all four corners to 0.1mm exactly, then use MANUAL_Z_HOME_POS in Marlin to set Home to 0.1mm. With this I finally have exact and repeatable Z coords.

In the meantime I have also discovered the magic of hairspray on a heated bed, what a difference a little spray makes. I didn't have to find anything specific, I use "Finesse Keratin Protein Firm Hold Unscented" on top of a layer of PET tape applied to 3mm borosilicate glass, and it works amazingly well.

I am at the point where I can almost reliably print any PLA object, but it is obvious that I am suffering from the infamous Z-wobble common in the design. I was under the impression that the redesigned Z axis brackets would solve this, but I guess the threaded rods supplied by ATI are too bent for the Z travel to be even. I have ordered some ACME threaded rods to replace them.

I mentioned earlier that I switched to the Azteeg X3 with the new TMC2100 drivers, and that is an amazing combination. At 12V the steppers were emitting a very uncomfortable high-pitch noise (even when not moving), but that was completely eliminated when I switched over to 24V. The machine is almost totally silent (no stepper noises).

My main goal when I chose the ORDBot platform was that it seemed like a good compromise of price vs performance, however considering the amount of time and effort I put into this, if I were to do it again, I would just buy a PrintrBot Metal Plus. At the time the import charges were quite prohibitive, but the prices were significantly reduced a few months ago. A friend of mine ordered one and was up and running after 30 minutes... and after six months I am just starting to print reliably.

I guess that on the plus side, I know a lot more about the machine, and can deal with problems much more effectively, but I wasn't expecting to buy yet another hobby.

Of all the things I bought, the only parts that have never failed me were the EZ Struder and the E3D v6. These two items are completely worth their weight in gold, and have worked reliably from day one.

Cheers,
Ben.

[fulg]

Hey PrintThings,

I've learned a few things about the bed level. First thing, it's so much easier with your endstop at the top of the Z axis rather than the bottom, even with some kind of screw adjuster, it's just not as good.

I've seen Nophead post about this on his blog, and was thinking about trying this out eventually. I am a bit concerned about crashing the head but maybe this isn't really an issue.

For now I am using this with great success: https://www.thingiverse.com/thing:26534.

Did you have to fight the Z-wobbles as well?

Cheers,
Ben.

[PrintThings]

I run an EZstruder with E3D V6 as well. My only slight complaint would be about the hotend, but nothing serious. You can tell where the polishing was done inside the stainless heat break tube, the diameter is larger at this point, and can cause PLA especially to get stuck and not want to pull back out of the hotend after it's cooled down. Turning off the hotend fan and letting the heat creep upwards a bit to soften the "plug" works to pull it out though.

I definitely get the Z wobble, especially near the top of the Z axis. I'd like to replace the threaded rods too but haven't got around to it, which replacement rods do you plan to use?

As far as crashing the head goes, it's never been an issue for me. Even if it did happen, because of the anti-wobble devices, you'd only end up with the weight of the gantry resting on the bed, which I doubt would cause any damage.

I messed around with kapton tape for a while, but ended up ditching it. I print right on glass now with everything. PLA and polyurethane stick great to hairspray, as you've discovered, right on top of the glass. For printing ABS and polycarbonate, ABS juice on the glass works great. I found the kapton tape annoying after a while, with bubbles forming from pulling off stuck on prints, having to use a razor to remove some, and gouging the kapton tape accidentally. With a larger print trying to warp, it'll even pull the kapton right off the glass sometimes. Ditching the kapton was hard for me because I bought an 8" wide roll of the stuff, and I really didn't want it to be a waste, but since switching to straight glass, I've had a way easier time.

[fulg]

I'd like to replace the threaded rods too but haven't got around to it, which replacement rods do you plan to use?

I bought 8mm ACME threaded rods *300mm) with the brass nut insert, http://www.ebay.ca/itm/181503464154. I have yet to receive them, but I did order 4 to maximize the chances of getting at least 2 straight rods.

I should specify that right now I have the E3D V6 Lite, but I have the parts to convert it to a standard V6 on hand. This means I still have a PTFE liner that goes almost to the melt chamber. In practice this hasn't been an issue because I need to heat the hotend to around 100C to swap out filament anyway (and if I do it right this also causes a cold pull of the old filament, but I'm not always successful).

It's funny, I also have a giant 8 inch roll of PET tape. Applying to the glass is not too hard with the soapy water trick, but it does mean the prints no longer come off the bed by themselves. I had tried the tape before trying hairspray, and now that I have something that works I don't really want to take it off. I'll try without it the next time I have to replace it. Initially I put on tape to (unsuccessfully) fix large PLA prints warping around their edges.

What do you use as a PLA cooling fan setup? I am still experimenting with various designs and slowly designing my own. Most of what is on thingiverse does not work on the EZstruder/E3Dv6 combination unless you have a standard X carriage (not shaped like an "L"), or expect a hotend that protrudes quite a bit from the bottom of the carriage. For now I make do with a variation of this mount, this fan and a desk fan, but it's a bit inconvenient.

Cheers,
Ben.

[PrintThings]

You'll have to let me know how those acme rods work out for you. Just going to print new anti-wobble parts and press in the brass nut?

I made my own cooling fan setup. I used a flexi-hose design I found on thingiverse, and then made the adapter to fit the fan and the nozzle on the end in sketchup. The radial fans are available on ebay for under $2 each. One of the fans was a lot more powerful than the other so I had to add some resistance so they turned on at the same and flow about the same. Before I did that one would come on around 10% power and the other not until 30%.

I can post the .stl files for the adapter and nozzles if you're interested. At first I used just one fan but found I got better results on overhangs facing the nozzle than ones facing away from it, so I added the other fan to get airflow on both sides. I like this arrangement because I can easily just bend the nozzles up out of the way when I don't need them. When I print polycarbonate, which really likes to warp, I bolt a clear shield up under the carriage that acts like a lid on the print, and then print a skirt around the part, so it basically has an enclosed print area to really keep the heat in. Works well with large ABS parts too.

Another worthwhile modification is to remove the fuse for the heatbed, put a heatsink on the MOSFET, turn one of the ebay 24V supplies down as low as it can go, about 19,5V, and then use that on a 12V heatbed. I get about 15 amps when it's cold, it'll hit 110C in about 60 seconds, and I've had it all the way up to 175C experimenting with polycarbonate. I could never go back to the slow and painful heatup of a 12V bed.

Here's my build thread, which didn't really go anywhere, but it's got a few pics of my machine if you're interested. viewtopic.php?f=33&t=2596