SoliForum - 3D Printing Community — heatbed questions (thermistor type, cables, connectors)

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-20T21:14:13Z

great, I ordered some connectors for the heatbed power. What about the connector name for the thermistor cables?

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-15T00:19:26Z

I am fairly certain they are JST connectors. Do the math (Ohm's Law) to make sure you get ones rated sufficiently high. The ones SD provides stock are under-rated and their failure is guaranteed, it just depends on when. Heatbed connector failure is a recurring problem on the forums.

The PCBs have bad deltas near the edges just like the cheap Solidoodle heatpad. User TickTock has shown this, as has adrian, with IR imaging. Regardless, it is still better than the stock bed, from what I've seen.

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-14T18:41:57Z

The thing is I don't know if the issues with my silicone heatbed will go away with this PCB bed. People seem to have mixed and contradicting experiences with both. So I wouldn't want to chop off the cables of the stock heatbed if I'm going to use it in the end anyway. Sure, I can reconnect it, but if I can keep things pretty (I might sell my SD4 if things don't get fixed at this point) by buying $2 worth of connectors why not?

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-14T17:00:44Z

I do not know what they are called, but can't you use the existing wiring and plugs?

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-14T14:02:33Z

Thanks.
Also, what are the connectors called for the heatbed sensor and heater cables on the board (Solidoodle Board/ PrintrBoard)?

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-13T22:02:39Z

It should be fine...just do a PID tune when complete...again, you can snake the insulated leads under the cork or whatever bed insulator you are using (away from the PCB after the connections to the thermistor...

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-13T13:27:43Z

I'm not really worried about electrical insulation, but thermal insulation.
I think even if the cable on the bottom of the PCB heatbed will reach half of the surface temperature, won't that greatly affect the accuracy of the thermistor reading?
I know heat has some effect on current and voltage in cables, but that's as much as I know.

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-11T13:54:43Z

Fiberglass would be good, but you really don't need any if you are Kapton taping the thermistor in place; just make sure the leads aren't touching each other and tape it down.

I used standard 16GA hookup wire as leads...but to be safe, you can snake the insulated wire portion through your heat-insulator (cork) which should be on the bottom of the PCB heater anyway.

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-11T13:30:51Z

Thanks.
But what to insulate the leads with? Will heatshrink do?
Will a standard cable work while being exposed to a 100C+ surface?

Re: heatbed questions (thermistor type, cables, connectors)

2015-06-09T13:04:16Z

A standard 100K thermistor will do...insulate the leads; wire leaders to it with solder or crimped ferrules and Kapton tape it(and the wiring) to the back of the PCB; dead center...

heatbed questions (thermistor type, cables, connectors)

2015-06-09T12:43:42Z

So by some magic the MK2B heatbed I ordered last year arrived about a month ago and when checking it, no cables were soldered as claimed, no cables were provided and no thermistor.

I know how to solder the main 12V cables, and still have the SSD relay wiring diagram from this forum, but what thermistor should I get and how to 'install' it on the heatbed?