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New Gear Solved Underextrusion Problems In 3D Printing

Getting a good, strong 3D print is a mess. Maybe another way of saying it is 3D printing with a CR-10 is a labor of love. I’m told the CR-10 is a capable machine. On good days it does what I need. I’m told something like the Prusa i3 requires substantially less tinkering, but then I find the occasional Youtube video where a person has a mess with those, too. It seems there is no 100% perfect solution.

Either way, I’m a tinkerer so here we go.

I was facing underextrusion on pretty much every print. The underextrusion wasn’t BAD and my picture of it isn’t great, either, but you could see missing lines from the print that should clearly be in there. Missing layers means the plastic didn’t get squirted where it was supposed to. It makes prints weak. I’m not overly concerned about the aesthetics, but that’s not ideal either.

I picked up a $6 back of steel extrusion gears from Amazon that had much more aggressive teeth than my stock CR-10. My previous gear seemed kinda worthless and it had no shortage of ground-up PLA dust on it. Maybe cleaning that would have helped. I installed the new gear, recalculated my e-steps, and tossed the correct code into Cura. My very first print has zero underextrusion. Problem solved. That NEVER happens.

Note:  Ignore the crunch edges.  That’s the brim that suddenly became a real pain to get off a few weeks ago.  It needs to be sanded off.

Before New Gear

 

After New Gear

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PCB Routing Tip

This one is common sense.  I don’t have common sense so I had to learn it the hard way.  When routing tough boards, we have to push the tolerances of our clearances from the trace to the enemy pads.  I’ll define “enemy pads” as those pads we don’t want our current pad to touch.  When doing layout for boards where clearance isn’t an issue, there is no reason to risk wasting your future time.

Bad Example

Bad PCB Layout

With our LED here the Vcc flows to the Pin #2 (anode of the LED).  While doing so, it comes quite close to Pin #1.  In this case, there is no reason to route so close to the enemy pad.  The better habit to form would be to start drawing the trace at the anode and avoid Pin #1.

Good Example

GoodLayout

In this good example, I started with Pin #2 of the LED (anode) and came straight down before angling towards Vcc.  The distance between the Pin #2 trace and Pin #1 is maximized without any down sides.

Reality

In reality, this is an incredibly simple example and the LEDs pins give plenty of clearance to solder them later.  So, this example sucks.  However, by developing a habit of maximizing space between enemy traces and pads, we reduce the odds of messy soldering situations.  Last week I received a PCB in SOIC-8 SMD footprints.  I could have taken the approach outlined here with no downside, but instead, I routed my enemy traces way too close to the tiny SOIC-8 pads.  The end result was I ruined one of the pads on the board and wasted 3 hours as I had to solder up a new board.

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Trump Screws Electronics Enthusiasts

This is not a political thing I’m doing. I have no dog in the hunt over gay rights or the upcoming Russian invasion. I’m just a bad maker and worse engineer. However, I just heard today on the Macrofab Podcast that my unpopulated PCB orders will face a new government tax of 25%. A kit I wanted to sell for $8 will now have to sell for $10. I will sell less. Broke people who want to buy my kits will get less money for their buck.

I don’t know ANY of the details of the current macro trade stuff. I try to stay exactly five years behind on politics. (It’s much more fun.) What I do know is I’m taking a direct hit and my business will directly suffer. It’s one thing to charge more money on the consumer level. It’s another thing to affect the livelihood of small business owners.

Random Application of Tariffs

Another truly intriguing part about these tariffs is how selective they are in their taxation.

Unpopulated PCBs
If a printed circuit board (PCB) is populated with components in China, there is no additional tariff. The reasons for this seem intuitive. Apple has lobbyists. Apple doesn’t want their phones to go up 25%. It’s too bad smaller business owners don’t have any representation.

Flyback diodes
If a diode is to be used for voltage suppression, it is taxed. How in the hell do they know if I’m going to use a diode for rectification or voltage suppression? That’s a good one. Where did they find the tax attorney who has a background in electronics? That’s impressive, actually.

Potentiometers (not resistors)
Fixed resistors don’t get an additional hike. Variable potentiometers go up 25%. Who comes up with this stuff?

Transformers under 1kA
Transformers under 1KA – essentially all consumer grade transformers – go up 25%. The big, industrial transformers face no hit.

I’ve always been perplexed why the tax code favors horse farmers differently than corn or cow farmers. (Each group has varying lobbyist strength.) I’m not aware of the flyback diode industry having a powerhouse lobby that the rectifier diode industry just can’t keep up with.

Where Is The Money Going?

The real question is where is this money going? I did the unthinkable and Googled this tariff mess. I see both China and the US are cranking up their taxes. Ok. Is this to pay off the debt? Are they building a new Hoover dam? Are we invading a new country? I’m just trying to figure out why we’d reduce US prosperity and increase the prices of U.S. manufactured goods. If I know where my money (and business) are going, I’ll be more inclined to pony up.

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Baseline ADC Readings Through Serial on AtMega328p

I hope this is legal putting this here. This is modified code from the Make: AVR Programming book. If you wanting to hop from Arduino to C Programming, this book is INCREDIBLE! Seriously, just freakin’ buy it.

This code measures a voltage coming into PC0 and spits it out through the serial monitor. The scaling isn’t right, but adjusting the voltage on PC0 with a potentiometer delivers reasonable results.


// ************ ADC works well enough   
//p.135  AVR Programming Make Book Mostly ********************
// The scaling is screwy, but I can adjust a potentiometer 
//and get reasonable 8-bit data
// ADC is reading PC0.  

#include <avr/io.h>
#include <util/delay.h>
#include "pinDefines.h"
#include "USART.h"

static inline void initADC0(void) {
	ADMUX |= (1 << REFS0);  // reference voltage
	ADCSRA |= (1 << ADPS1) | (1 << ADPS0); // ADC clock prescaler /8
	ADCSRA |= (1 << ADEN);  // enable ADC	
}

int main(void){
	// Inits
	uint16_t adcValue;
	//uint8_t i;
	initADC0();
	initUSART();
	printString("Hello!\r\n");
	
	while (1) {
		ADCSRA |= (1 << ADSC);  // start ADC conversion
		loop_until_bit_is_clear(ADCSRA, ADSC);  
                // wait until finished
		adcValue = ADC; // Read ADC in
		
		_delay_ms(50);
		transmitByte(adcValue);
		_delay_ms(1000);
		
	}  // end big loop
	
	return(0);
}
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Is there evil in the world? Yes! LabVIEW!

My boss – okay he’s a professor at school – at my internship – okay, it’s an unsanctioned internship and I’m working for free – asked me to clean up the GUI on a LabVIEW power measurement circuit. I have vast experience with .css from my html background so I thought “no problem”.

I’ve debated if evil truly exists beyond the realm of the mentally ill. Evil acts certainly occur. Is Jeffrey Dahmer evil or just crazy? Maybe this crazy vs evil thing is a semantic mess, but we treat evil much differently than we treat insanity in American culture.

Now I have my answer. I can say definitively, 100%, without a doubt that evil exists in the world and I can only assume that the creators of LabVIEW over at National Instruments are not mentally ill. It would take too many people all with the same scheming hands and maniacal laugh to be working in unison to create a tool that has created so much wrong in the world.

How many hours do I need to invest in adjusting the size of font? Should it take hours and hours to change the background color? Why can’t I just select the good ol’ color codes from the html world or the Photoshop world? Why is it when I save a file, I’m asked all these nonsensical questions when the current paradigm of saving files is well-understood and works incredibly well. Why is it the movement resolution of a label is high when three inches from the gauge, but heavily quantized when close to the target.
WHY CAN’T I ZOOM??????

There isn’t a single facet of the LabVIEW software that doesn’t take 10x longer than it should to learn. At the end of the day, the hardware behind LabVIEW is so ridiculously high priced that I can’t think of an instance where the graphical software makes a bit of sense to implement. Because LabVIEW will waste hours and hours on things that Microsoft Paint mastered in 1991, the overall project time isn’t all that different from what one may expect when programming in C.

LabVIEW is evil. Case closed.