{"id":240,"date":"2020-09-29T15:16:01","date_gmt":"2020-09-29T15:16:01","guid":{"rendered":"http:\/\/www.beer.org\/blog\/?p=240"},"modified":"2020-09-29T18:19:01","modified_gmt":"2020-09-29T18:19:01","slug":"3d-printer-upgrade-klipper-thermistors-and-power-supplies","status":"publish","type":"post","link":"https:\/\/www.beer.org\/blog\/index.php\/2020\/09\/29\/3d-printer-upgrade-klipper-thermistors-and-power-supplies\/","title":{"rendered":"3D printer upgrade, Klipper, thermistors, and power supplies."},"content":{"rendered":"

Boring preamble<\/h1>\n

It took forever for my 3D printer to reach temperate and then the bed heater just stopped working. Not sure what happened.\u00a0 So friend Derwyn gave me a spare Prusa magnetic heated bed.\u00a0 This was a terrific gift!<\/p>\n

Bad: it’s 24v and the rest of my printer is 12v.<\/p>\n

Good: I had a 24v 60A DC power supply!<\/p>\n

Good: I had a Creality CR10s v2 controller that has both 12v and 24vdc inputs.<\/p>\n

Bad: my extruder heater was 12v, fans were 12v, etc.\u00a0 I don’t have a spring steel sheet.<\/p>\n

Good: those items are cheap on Amazon.<\/p>\n

Anyway, to make along preamble shorter, I changed everything all at once except some acrylic and some bolts.\u00a0 \u00a0I also decided Klipper<\/a> was worth a try because Marlin is a disgusting mess of nearly incomprehensible twisty #ifdef’s and my printer was a mashup of several different printers.\u00a0 Let me tell you, Klipper is a breath of fresh air and worthy of a different blog post.<\/p>\n

Meat of this article<\/h2>\n

I was having trouble getting the PID on the extruder to settle on a temperature.\u00a0 \u00a0Especially the high temperatures (230+):<\/p>\n

\"PID<\/p>\n

 <\/p>\n

It took forever for prints to start because Klipper could not get the printer to the proper temperature.<\/p>\n

I accidentally stumbled upon this Hackaday<\/a> post which is a link to this<\/a> fellow who helpfully outlines the process to change a capacitor to better filter power on the CR10s v2.0 board<\/a> that I have.\u00a0 Could that be the problem?<\/p>\n

So first I decided to check the current state of things.<\/p>\n

\"\"

Power with Extruder running.<\/p><\/div>\n

\"\"

Power with Extruder and Bed heater running<\/p><\/div>\n

 <\/p>\n

Here’s the best part.\u00a0 Normally, Octoprint turns on the bed heater first, and when that comes up to temperature, it turns on the extruder heater.\u00a0 However, I turned on the extruder first and set it to 260C.\u00a0 Then I turned on the bed heater.\u00a0 The two photos above show that.\u00a0 Here’s what happened on Octoprint:<\/p>\n

\"\"

Note how Klipper was able to use PID to get the temperature under control until I turned on the bed heater<\/p><\/div>\n

 <\/p>\n

Look how the poor power filtering was affecting the ADC measurements for the Extruder heater?\u00a0 The NTC 100k (B3950) thermistors only read 380ohms (approx) at 240C.\u00a0 That means a difference of only a few ohms at high temperatures has a big affect on temperature.\u00a0 So voltage swings will dramatically affect ADC measurements, causing havoc with PID!<\/p>\n

I didn’t feel like waiting for Digikey and paying the shipping so I used a 220uf electrolytic capacitor instead.\u00a0 Ugly as fuck but much better.<\/p>\n

 <\/p>\n

\"\"<\/p>\n","protected":false},"excerpt":{"rendered":"

Boring preamble It took forever for my 3D printer to reach temperate and then the bed heater just stopped working. Not sure what happened.\u00a0 So friend Derwyn gave me a spare Prusa magnetic heated bed.\u00a0 This was a terrific gift! Bad: it’s 24v and the rest of my printer is 12v. Good: I had a… Continue reading »<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-240","post","type-post","status-publish","format-standard","hentry","category-tech-stuff"],"_links":{"self":[{"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/posts\/240","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/comments?post=240"}],"version-history":[{"count":3,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/posts\/240\/revisions"}],"predecessor-version":[{"id":248,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/posts\/240\/revisions\/248"}],"wp:attachment":[{"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/media?parent=240"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/categories?post=240"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.beer.org\/blog\/index.php\/wp-json\/wp\/v2\/tags?post=240"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}