dumb build mistakes

[seanriddle]

Here are the dumb build mistakes I made building the Max v2- maybe this will help someone avoid making the same ones. The instructions are extremely clear, with just a couple of places where I was temporarily confused. Still, I managed to goof up a few times.

I installed the upper tower mounts with the top section base plate upside down. It feels like you are going to break the pieces getting it together in the first place, so I was very hesitant about taking it apart and reinstalling, but I decided to anyway. It was a pain getting them apart, but I was more comfortable putting them back together again with the top section base plate right-side-up.

I flipped 2 of the cheapskate backs. I knew the holes had to match up, so I think what happened is that I had a hard time pressing the u-joint carrier bases in, and flipped the wooden pieces without thinking about it. It wasn't hard to flip them around, except that I had really tapped in the t-nuts as the instructions said. Some melamine cracked off, but that got covered by the spacers later.

I misunderstood the line in the belt routing instructions "outside of the #1 idler bearing" and routed the belt on the other side. I didn't notice the difference comparing to the diagram, either. After printing the 2 fan shrouds and a couple of calibration cubes, I noticed a pile of "eraser leavings" at each tower. Nothing was rubbing above the base, but it looks like the back side of the belt was rubbing against the sharp corner underneath when the carriages were moving up. It doesn't looks like much got rubbed off, but when I rerouted them, I flipped the belts around so the rubbed parts are at the top where I can keep watch on them.

Not really a dumb mistake, but I could not get the 8 extruder and fan wires routed through the tower. I could get them a couple of feet in, but no further. I thought about using some wire pull lubricant, but I was afraid some would leak out into the base. Instead, I ran a spare length of 22 ga solid core wire through and soldered it to the 8 wires and pulled them back through. It worked very well.

My kit came with just 5 feet of 18 ga and 22 ga 4-conductor cable, although the parts list shows 10 feet of each. That was enough 22 ga, but not nearly enough 18 ga, especially since you are supposed to use 17 inches from the Rambo to the bed. I had to go to Home Depot to get some. My kit was also missing 2 6-32 1" Phillips pan head screws to hold the LCD assembly together, and a #4 3/8 Phillips head sheet metal screw to attach the fan shroud.

I thought I had 6 leftover washers, but I tracked those down to the top idler bearings. The instructions say to use washers for the lower ones, but not the upper ones. I do have 10 extra plastic bearing rollers. One typo I remember is in chapter 5B, installing the Rev 3 Onyx: "orient the Onyx heated bed such that the LED is farthest away from you and near the Z-axis." But on the Rev 3, the LED is on the opposite side. I think that section just got copied from the original chapter.

When I removed the flashing from the delta arms, I noticed that the mold lines don't line up well; on one side of the flashing, the arm is noticeably smaller than on the other side, like the plastic didn't fill the mold all the way? I'm not sure if this will cause any issues, but I'll keep an eye on it.

I had a hard time getting the print bed to 90 degrees, so I used 2 runs of 16 ga wire from the Rambo to the print bed. It was still slow, and I could hear the Rambo fan slow way down when I turned on the bed heater, so I ordered a 600W modular P/S. This one has a max of 46A for 12V, compared to 22A on the original P/S. Instead of cutting the P/S wires (since this one has a 3-year warranty), I cut down a couple of ATX extension cables and wired them to the Rambo. Now the Rambo fan is steady even with both heaters going, but it still takes a while to heat the bed, even with a towel.

I hooked up a KILL-A-WATT meter between the printer and the AC socket, and it shows 190W when both heaters are on 100%. During printing, the reading varied from 60W to 120W. I'm going to get a little UPS, since I've already had a couple of power blinks that killed print jobs.

I've had a few SD read errors, so I need to read up on when I have to unmount the SD card. I thought I was doing everything right, but I've gotten an error on 2 different cards- the one that came with the Max and another one that I use all the time for other stuff. This has happened both when the printer has been plugged into the PC and when it wasn't plugged in. When it was plugged in, the error was logged to the Repetier-Host log, but when it wasn't plugged in, there was no message. The print head just stops moving; it doesn't return home and the heaters stay on. But I can control the Rambo normally with the dial.

Sean

[nitewatchman]

Not really a dumb mistake, but I could not get the 8 extruder and fan wires routed through the tower. I could get them a couple of feet in, but no further. I thought about using some wire pull lubricant, but I was afraid some would leak out into the base. Instead, I ran a spare length of 22 ga solid core wire through and soldered it to the 8 wires and pulled them back through. It worked very well.

I had a hard time getting the print bed to 90 degrees, so I used 2 runs of 16 ga wire from the Rambo to the print bed. It was still slow, and I could hear the Rambo fan slow way down when I turned on the bed heater, so I ordered a 600W modular P/S. This one has a max of 46A for 12V, compared to 22A on the original P/S. Instead of cutting the P/S wires (since this one has a 3-year warranty), I cut down a couple of ATX extension cables and wired them to the Rambo. Now the Rambo fan is steady even with both heaters going, but it still takes a while to heat the bed, even with a towel.

I ran into the same issue with the 8 wires. I resulted to using the cleaning rod for my .204Ruger AR. Just fits the hole in the column.

I am also using a modular P/S, (Corsair RM750) to manage wiring and get rid of those that are not needed. I will use the 12VDC buss on the P/S. There are two of them with 4 circuits each. I am using a Wago Splice block to merge the 4 - 12VDC wires into a single #14 to feed the bed input on the RAMBO.

I have had my share of do overs also. Fortunately none fatal so far.

nitewatchman

[atoff]

I thought I had 6 leftover washers, but I tracked those down to the top idler bearings. The instructions say to use washers for the lower ones, but not the upper ones. I do have 10 extra plastic bearing rollers. One typo I remember is in chapter 5B, installing the Rev 3 Onyx: "orient the Onyx heated bed such that the LED is farthest away from you and near the Z-axis." But on the Rev 3, the LED is on the opposite side. I think that section just got copied from the original chapter.

Yeah, just noticed I didn't have washers on mine. One of the screws is now sunken into the melamine, having cracked / gouged it in. Hopefully I can install a better tensioner and it won't matter.

[forrie]

I had the same issue with the missing screws for the lcd and not installing the washers. I'll fix the washers at a later stage, no damage done.

I also found the cheapskates challenging. It seems to me some of the steps are a bit backwards in the manual and would make more sense if they are reordered. But that's just my logic...lol. I knew they only went together one way, but still managed to stuff it up first time around.

I also had spare 10 of the plastic spacers - and quite a few other parts like the adjuster cams and bearing spacers.

A few other things as well that arn't in the manual:

* I had to change the Baudrate in the EEPROM to match the USB driver before I could connect Repetier.
* Had to change the Max PID temp for the hot end from 255 to 128 before the auto tune would work. I'll change it back once I get the fan shroud printed.