Other thermistor brands??

[skyjuice]

Do any of you have any recommendations other than the ones sold with the V3 kit (thermistor)? I tried these:

https://www.amazon.com/gp/product/B0150 ... UTF8&psc=1

and they seem to not be that accurate and fail/glass bulb chips and snaps very easy when moving the two leads apart. Also tried these:

https://www.amazon.com/gp/product/B018Q ... UTF8&psc=1

They work ok, but are very thin and glass bulbs also tend to split when moving leads apart from one another.

Have any of you had any success with other brands? The ones on the Seemecnc website are $6 a pop plus shipping, so thats why I am looking elsewhere. https://www.seemecnc.com/collections/pa ... r-100k-ntc

Thanks!

[mhackney]

What problem are you trying to solve? The thermistors SeeMeCNC uses are a standard part you can easily find the part number if you search here. They can be found on mouser, eBay and lots of other places.

[Xenocrates]

Personally, I find thermistors in general pretty bad. The potted ones, which are encased in cartridges (E3D style), or M3 studs are OK to work with, but otherwise I avoid them where I can. I much prefer a PT100 (Thermocouples work too, but I wanted the cartridge and at the time thermocouples weren't available for the E3D in that form-factor)

That said, while I have broken thermistors installing them, mostly once they are installed they are harder to damage (The V2 stock hotend could have them come out if it wasn't tape wrapped), such as my occasional bad habit of having hung E3D heater blocks by just their thermistor leads. Haven't broken one yet doing that.

If all you're looking for is one that's easy to work with for the hotend, the M3 stud thermistor here works OK, but is dubious for a heated bed install (I have no idea how well the PCB would hold the threads, but I suppose it could be thermally epoxied in place or something)

[skyjuice]

What problem are you trying to solve? The thermistors SeeMeCNC uses are a standard part you can easily find the part number if you search here. They can be found on mouser, eBay and lots of other places.

The problem I'm having is the actual glass bulb is so delicate that when I go to separate the two leads coming from them, I sometimes crack the globe and have to start over with a new one. Just looking for something better out there that isn't so weak is all. The ones from Seemecnc are discontinued from Semitec, so I'm on the lookout for something better. Just been a problem for me, maybe not for most people though.

[skyjuice]

Personally, I find thermistors in general pretty bad. The potted ones, which are encased in cartridges (E3D style), or M3 studs are OK to work with, but otherwise I avoid them where I can. I much prefer a PT100 (Thermocouples work too, but I wanted the cartridge and at the time thermocouples weren't available for the E3D in that form-factor)

That said, while I have broken thermistors installing them, mostly once they are installed they are harder to damage (The V2 stock hotend could have them come out if it wasn't tape wrapped), such as my occasional bad habit of having hung E3D heater blocks by just their thermistor leads. Haven't broken one yet doing that.

If all you're looking for is one that's easy to work with for the hotend, the M3 stud thermistor here works OK, but is dubious for a heated bed install (I have no idea how well the PCB would hold the threads, but I suppose it could be thermally epoxied in place or something)

Good answer and I truly thank-you for taking the time to respond. I'll definitely look into your recommendation!

[geneb]

...or you could just be more careful and not gorilla the poor things.

g.

[skyjuice]

...or you could just be more careful and not gorilla the poor things.

g.

Assuming you are here with me, watching me finesse them into place? Yup, didn't think so. I am being very careful and some of them still crack. I'm not sure if it's just me, but I am becoming very used to having trouble, almost every couple of days with the heating elements in the V3. Maybe it's my fault, it's anyone's guess at this point as I've replace so many parts already trying to figure this out.

[geneb]

I've personally built 8 of these and supervised the construction of 20 more....and I literally wrote the manual on how it's done.

Go easy on the thermistors. They're delicate.

g.

[skyjuice]

I've personally built 8 of these and supervised the construction of 20 more....and I literally wrote the manual on how it's done.

Go easy on the thermistors. They're delicate.

g.

I appreciate your knowledge! If you could offer me some wisdom on why my hot end stopped heating up, I would be extremely grateful! I see the LED's turn on when I manually turn on the heat on both the bed and nozzle. I also see the red LED turn on on the hot end when heat is turned on. When that happens though, the hot end is not heating up. I checked the cable plug and thats tight, I even have a printed brace for it that holds it pretty well in place. Could it be my resistor? I got 3.3 ohms off it. This happened after I removed a clog in the nozzle and turned it back on. ANY help would be appreciated!!!

[Xenocrates]

I've personally built 8 of these and supervised the construction of 20 more....and I literally wrote the manual on how it's done.

Go easy on the thermistors. They're delicate.

g.

I appreciate your knowledge! If you could offer me some wisdom on why my hot end stopped heating up, I would be extremely grateful! I see the LED's turn on when I manually turn on the heat on both the bed and nozzle. I also see the red LED turn on on the hot end when heat is turned on. When that happens though, the hot end is not heating up. I checked the cable plug and thats tight, I even have a printed brace for it that holds it pretty well in place. Could it be my resistor? I got 3.3 ohms off it. This happened after I removed a clog in the nozzle and turned it back on. ANY help would be appreciated!!!

Have you measured the voltage drop across the resistor? It may be that there is an open now, possibly due to an intermittent crimp on the thermal fuse or similar. If you have voltage drop across it, then it should by all rights be heating, and you should be able to feel it. If not, track upwards until you find a voltage drop, then you have found approximately where your open is.

[skyjuice]

I've personally built 8 of these and supervised the construction of 20 more....and I literally wrote the manual on how it's done.

Go easy on the thermistors. They're delicate.

g.

I appreciate your knowledge! If you could offer me some wisdom on why my hot end stopped heating up, I would be extremely grateful! I see the LED's turn on when I manually turn on the heat on both the bed and nozzle. I also see the red LED turn on on the hot end when heat is turned on. When that happens though, the hot end is not heating up. I checked the cable plug and thats tight, I even have a printed brace for it that holds it pretty well in place. Could it be my resistor? I got 3.3 ohms off it. This happened after I removed a clog in the nozzle and turned it back on. ANY help would be appreciated!!!

Have you measured the voltage drop across the resistor? It may be that there is an open now, possibly due to an intermittent crimp on the thermal fuse or similar. If you have voltage drop across it, then it should by all rights be heating, and you should be able to feel it. If not, track upwards until you find a voltage drop, then you have found approximately where your open is.

This might sound dumb, but do I measure the loss/drop after I manually turn the hot end on? I only have a few seconds to do that before it goes DEF then decoupled.

[Xenocrates]

My suggestion would be to start by using alligator clips or such to hold the multimeter probes to the leads into the resistor, then using either Peak-hold, or filming the multimeter readout (Dependent on meter features.)

[geneb]

I suspect he doesn't have a meter.

He discovered the issue - a blown thermal fuse.

g.

[moo77777]

I have blown 2 fuses by not being careful and turning off my printer when I am done using it at temp. You must be mindful of this fact and probably avoid shutting the thing off until the hot end reaches ~90C. On the plus side, I have gotten pretty good at replacing components on the hot end without disassembling the whole thing!

[geneb]

With the amount of air the cold section fan pushes, cool down is pretty quick once the heater is off.

g.