Hello All,

I'll begin by stating I am a complete NOOB.

I built machine heavily based on the first two PhlatPrinters ( see pics ) using stepper motors pilfered from Cricut Personal Machines, which I believe to be NEMA 17, and a Chinese TB6560 driver board. If you look at the pics you can see the carcass is made from scraps of plywood and MDF salvaged from the neighbor's trash. I've milled planks from discarded furniture, like old computer tables and hutches to build the carcass.

So, realizing this isn't a real Phlatty, I completely understand if the response is less than overwhelming. But I am hopeful someone will be willing to offer some assistance.

I've dialed it in and the fastest it'll move is 17 ipm. The board has been configured for 1/8 micro steps. The axes move with a plenty of speed until they've been adjusted for accuracy.

So, if anyone here is still reading and is willing and/or able to offer any assistance I am all ears.

Thanks,

g

 

looks pretty good to me

 

I didn't know anyone had responded. I thought I'd receive an alert via email when someone did. Hence the reason I am only just now responding.

The axes are basically direct drive excluding the Z axis which uses 5/16-18 all thread coupled directly to the motor shaft via a hose and clamp.

The X axis uses a roller chain with both the drive and driven sprockets identical.

The Y axis is driven by a timing belt. Both the drive and driven pulleys are the same diameter.

I'm using a 13.8v, 3.6a continuous current Power Supply. I am not sure how to answer the question regarding the drivers. Native Units are set to inches. I have the controller set to 75% current to keep the motors from getting hot. I have had it set to 100% current with these settings but was unable to detect any difference in speed. The motors run cooler @ 75% current.

All the axes move considerably faster until they are calibrated. Once all the fine tuning is done everything slows to a crawl.

Can you tell me, in a basic system with 3 axes, does stepper motor speed increase if the micro steps are increased/decreased?

In other words, if I change from 1/8 step to 1/2 or full step, will the IPM increase move faster once all is tuned?

Thanks,

g

 

Thanks, Jnida63. I appreciate the kind words.

g

 

Thanks for all the tips and links. I have an 18v PS that I'll try. I tried it before and got no response. I remember now that the pos and neg wires were reversed, pos on the outside instead of center of the connector and I may have had them reversed on the board.

As to the sizes of the sprockets etc., since the drive and driven are the same size wouldn't the ratio be 1:1 and regardless of the pitch, teeth diameter?

I was gonna ask you how to calculate the steps per inch but I'll bet one of the links you posted will have that information.

Thanks again for the help,

g

 

I hooked up a 31.5v HP power Supply to the Z axis. I removed the connectors on the other two axes over concern that the steppers might smoke. It did seem moderately faster but not much. Before I could complete calibrating the Z axis stopped moving. When I flipped the machine over to see what the problem was the motor had become so hot the tubing used to couple the drive screw to the motor had melted through. It was too hot to touch for even a second. I was sure the motor was fried. To my surprise after things had cooled and were reconnected to the 13.5v everything was functioning like before.

I think I'll leave well enough alone as far as power supplies are concerned.

I tinkered with different step and micro step values. The board can be configured for full, half, eighth and sixteenth steps. I was unable to gain any appreciable speed.

g

 

I run my printer on 24V. My motors are never hot. I did had once a motor getting hot. I was playing with the pots settings for the motor on the driver. I've set the voltage too high. It should have been something like 2.9V and I had it set to 4V. Don't quote me on the exact values. After I set it back to the correct value the motor never got hot again.

 

Hi, Thanks for the info. My motors are NEMA 17 and may not be as hardy as what you have. I noticed recently in the User's Guide for the TB6560 board I have, the max voltage recommended for NEMA 17 Steppers is 16VDC. After the incident with the 31.5 volt power supply I am reluctant to exceed their guidelines.

I scaled down the M_PhlatGlider.cnc gcode to match my table size and am about to try it out fully for the first time.

The next thing I need to do is figure how to restructure the gcode so I can cut the models full size.

I'll let y'all know how it goes.

g

 

I don't know about NEMA 17 motors and it my be true that they shouldn't be run with more then 16V. The voltage I was talking about is the voltage that controls the amperage that goes through the motor. I thinkg the 6560 has amps setting for the motor. It may be that you have it set too high and that is what made the motor run hot.

I'm not sure what you mean with 'restructure the gcode' but if you use SketchUp and SketchUcam it's very easy to redraw and make a new gcode.

 

The voltage I was talking about is the voltage that controls the amperage that goes through the motor
I had the current (amps) set to the lowest setting. It must have run hot due to the excessive voltage.

I'm not sure what you mean with 'restructure the gcode...'

I figured out how to re-arrange components in Sketchup and fit them to the table size that matches my machine to cut the models at there original size.

There must be a setting in Mach3 that will speed things up that I haven't stumbled on.

g

 

I think you may be right. Its a mechanical problem. Some gearing and pulley ratios need adjustment.

 

Thought I'd post an update. I hadn't actually attempted to print anything so, with the machine as it is, I plugged in the scaled down version of the Phlat_ TRex that I'd configured to fit my machine and it goes faster than anticipated. I used a piece of foam that had already been cut on a bit as it was a test. I also didn't realize the machine was gonna push out the sheet about six inches at the start so I had to stop before the print completed because it was gonna run past the end of the sheet. I would estimate that about 2/3 of the model printed in just a bit over six minutes before I stopped it. So the whole thing would have completed in about 10 minutes. There are a lot of intricate cuts in the T-Rex which makes me think its not the fastest model to print to begin with.

Would more speed be better. Yeah, probably. But, I think I can live with it the way it is.

Suffice it to say that I am not unhappy.

Whoo hoo!

g

 

Its nice to hear some encouraging words, ewo. Something else I meant to mention is the bit I used in the Dremel Tool was just a plain old 1/16" drill bit and the cut probably was not as clean as it could have been. Maybe if the tip of the bit was ground flat it would cut smoother laterally.

Any suggestions pertaining to bits would be greatly appreciated. I would prefer a good 1/16" bit over a 1/8" bit. I think Dremel only offers a 1/8" spiral bit.

g

 

I remember seeing those and thinking the length of the cutting surface looked too short. I guess not after all.

g

 

I don't know for sure why your machine pushed the material 6" out before starting the actual cut but I'll guess that it is because you've set the 'safe area' in SketchUcam that way. before I generate the g-code I make sure all the parts are as close as possible to the zero point of the axis' that way the pushout of the material is minimal, mostly 1/16" to 1/8".

 

I might have just forgotten to "Home" or " send the printer home" before I started. I'll figure it out in time.

Another thing I did that I didn't mention, which may have improved the speed, is to change the wire size from the 13.8v PS to the Board. I had some pretty small wire on there, maybe AWG20 or AWG22, which I replaced with some really good AWG14 silicone RC grade multi-strand wire. Its really hard to pump the current through wire that's as small as what was on it.

g

 

Or you forgot to zero all the axis' once you had them at the right spot. I had postit notes on my monitor saying 'zero axis' and wouldn't you know it, I still forgot to do it from time to time and the gantry zipped across or the material popped out of the printer.

 

I sounds like it's a common thing to forget to do.

g