Shift in layers/ voltage fluctuation

[jmargush]

I was recently printing pulleys for my robotics team and noticed that I'm getting shifts in my layers by about 1.35mm via x axis. I made sure my belts were tight and that my glass plate wasn't shifting. I measured my voltage, on my ATX power supply, at different times when the printer was on and these were my results

•Powered On: 12.43
•Heating (bed and hotend): 11.17
•Printing: 10.95-10.7

I don't know if these are normal readings or not. I look forward to figuring out this issue. Thanks for the help.

[Jimustanguitar]

If you've got an ATX power supply, some of them will regulate the overall voltage of the supply based on the load on the 5V rail. Not all supplies do this, but some do. You can put a load resistor on one of the 5V leads (going to ground, of course) and smooth out some of that power fluctuation. I did it on a revision of my old machine, and it helped. I found some aluminum heatsink encased resistors that were sold as LED load resistors to make analog turnsignal flasher elements work with low load lights.

[jmargush]

If you've got an ATX power supply, some of them will regulate the overall voltage of the supply based on the load on the 5V rail. Not all supplies do this, but some do. You can put a load resistor on one of the 5V leads (going to ground, of course) and smooth out some of that power fluctuation. I did it on a revision of my old machine, and it helped. I found some aluminum heatsink encased resistors that were sold as LED load resistors to make analog turnsignal flasher elements work with low load lights.

But if I'm using 12volts why would I put a load resistor on the 5volt. Could you, please, elaborate and possibly show me where to get one of these?

[Xenocrates]

The answer has to do with the design of the regulation circuitry in the power supply. For some time, given that a load on 5V was expected at all times the computer was on (And still is, as both the CPU and hard-drives, as well as any USB systems will pull on it), they designed using an architecture that expected some load on that rail to reduce costs and improve efficiency. More recently, and in higher end models, almost all of the AC-DC circuitry is delivering 12V and only 12V, with DC-DC converters to handle the level shifting.

So what you're looking at is a result of what is called cross-loading. Without a load to pull down the 5V (And sometimes 3.3) rail, it can rise while reducing the power on the 12V line. A pair of these these should work fine for resistors.

Edit: I Derped the initial resistors a little. You may need more or less, but really, 5W, which was my initial recommendation isn't going to help it.

[jmargush]

The answer has to do with the design of the regulation circuitry in the power supply. For some time, given that a load on 5V was expected at all times the computer was on (And still is, as both the CPU and hard-drives, as well as any USB systems will pull on it), they designed using an architecture that expected some load on that rail to reduce costs and improve efficiency. More recently, and in higher end models, almost all of the AC-DC circuitry is delivering 12V and only 12V, with DC-DC converters to handle the level shifting.

So what you're looking at is a result of what is called cross-loading. Without a load to pull down the 5V (And sometimes 3.3) rail, it can rise while reducing the power on the 12V line. A pair of these these should work fine for resistors.

Edit: I Derped the initial resistors a little. You may need more or less, but really, 5W, which was my initial recommendation isn't going to help it.

Is this the reason my layers are not lining up? Would upgrading to the new power supply, used in the v3, be a good idea?

[Xenocrates]

No, and probably. There are many possibilities on why the layers are shifting. If it's a very consistent shift, then it is very possible you have a flat spot on the wheels that hasn't rolled out, or damage on the bearing surface of the rail, or some other mechanical issue. If it's random, it is more likely that you have high spots on the layer, such as crud accumulating on the nozzle and falling off, that the nozzle is catching on, or an intermittent electrical connection.