Measuring the Temperature at the Nozzle  

RE: Measuring the Temperature at the Nozzle

The heater block (into which the nozzle threads) has an embedded thermistor that is reasonably accurate - with an admirably fast response.  You can read the temp directly from the MK3 LCD.

If that doesn't tell you what you want to know, or need to automate the measurements, there is a clamp screw on the bottom of the heater block - you could probably attach a TC weld there. 

As for "extrusion temperature" -  are you planning on measuring the extrudate temperature?   lol  ... good luck with that one. High resolution IR, maybe.

RE: Measuring the Temperature at the Nozzle

Given that the thermal conductivity of the heater block assembly is ~500x better than the thermal conductivity of PLA (other plastics are similar), and given that the power of the heater is 3x more than what's needed for maintaining the temperature even at maximum extrusion rates of common filaments, you can safely assume that the heater, the heater block and the nozzle itself all have the same temperature and that it is very close to what you set on the printer.

What WILL be different is the temperature of the extruded plastic, particularly at larger volumetric extrusion speeds (larger flows). Again, because of the low thermal conductivity of the plastic. But that one is very very hard do measure, as @tim-m30 says, a high-res thermal camera could be an option.

RE: Measuring the Temperature at the Nozzle

Okay, yes, thank you for the responses!

I think I am moreso after the temperature of the material coming out of the nozzle, like @vojtech-p6 mentioned. I think there is one company, Pollen AM, who has a sensor built next to their extruder nozzle and a heater which can detect the temperature of the material and adjust accordingly on the fly. That is why I asked.

RE: Measuring the Temperature at the Nozzle

Hello,

Can we measure it using thermostats?

RE: Measuring the Temperature at the Nozzle

Hi Elizabeth, 
No you cannot measure using a thermostat. A thermostat is a device that controls a heating or cooling element to achieve a given temperature. 

the Prusa mk3s  uses a thermistor in conjunction with a microcontroller and a field effect transistor in conjunction with a PID routine, to emulate an intelligent thermostat to control the extruder temperature (same setup for the heatbed...)

what you need is a form of thermometer  which Measures temperature...  
BUT it's difficult to get an accurate reading off either a traditional bulb thermometer or an infra red thermometer because both of these have relatively large sense areas of which only a tiny proportion would be in contact / scanning the nozzle temperature so the rest of the sensor would be at a different temperature, wrecking the accuracy
I use a thermocouple and temperature meter, and to simply measure the extruder temperature I would drill a small hole into the heatblock to insert the thermocouple bead and use kapton tape to hold the thermocouple bead in position. 
however that is possible because I have the thermocouple equipment...

you could use something like this https://www.ebay.co.uk/itm/TM-902C-K-Type-Digital-Thermometer-50-C-to-1300-C-with-Thermocouple-Sensor/312703518274?_trkparms=ispr%3D1&hash=item48ce950642:g:T8cAAOSwKZtdpBTA&enc=AQAEAAACUBPxNw%2BVj6nta7CKEs3N0qV0ENNa76S9f4z7Rgwd50y9HFKSFFVfsqQlcJ0FtybBvDm%2BjjJT99qA0pXVk5vvOFkWOgcj0hXYcICzdIHExrGJy4Kzfu132LwWAg8JfiLPxwa%2F4H1cPQw8qQn2WSlGsRTlO3HTTMbM7csz3OOSmPQgNgqz3Jhl1J%2BV4BSoRAnlUrxVupMaCjj%2F5TWwjBgcd7eY3c3y9sjQ%2B6XPDmQ0gkb0MDsET%2FYKZGImqhEeX4BxlIfWjPwFIw5A4WLHJiMU66QLxonPWMokOb5MVdryIJGd6HsUfCnMToaTfPlXowZ3ucPGHXStFicU5ft7JEhFmzO1k0%2F1UQceUaWSzdCZnvNGveL8LhkX7pGSy3vH%2FbKKJ1MS0tkqlDlB%2BsM6hX2G5et8pnVJT8n1e34R%2BH6LuSI78MEMaXITHn48RWXIK2BviUGG%2B6vVP02%2BP2xer43L9f1AmnD4gV1A3jYi4TU4dF%2FpyPLc8G1S0fY34kqlC4L2aJ4zCjExW4FWrkiEQatmnHozr%2Ff7kykfxxZJYWg4RJZUwEVZLVS1w7oSjn0AoTipTBx0W9dIeIksC5yrCHJS%2FwI4cn25JU2CMkWV8U5s3FbZjylelqdoqlkxCjXIxIjKgIBOO9xrjL2px4MmM4kJ58l5yQsFSXUNbpclhHlic1xuxiCEYNIgcpKZQFompepVS6UY7bCILFRmLbXv9Znfh2yZ74b%2F3UnPAg1ayDkMSBBX7jYWOVlhFIvCf9gHA%2FP9dfJlZv6xo%2FNTLWcZ1YPYpPs%3D&checksum=312703518274f15873459d9a46dfa5eea9601f8f4bce&enc=AQAEAAACUBPxNw%2BVj6nta7CKEs3N0qV0ENNa76S9f4z7Rgwd50y9HFKSFFVfsqQlcJ0FtybBvDm%2BjjJT99qA0pXVk5vvOFkWOgcj0hXYcICzdIHExrGJy4Kzfu132LwWAg8JfiLPxwa%2F4H1cPQw8qQn2WSlGsRTlO3HTTMbM7csz3OOSmPQgNgqz3Jhl1J%2BV4BSoRAnlUrxVupMaCjj%2F5TWwjBgcd7eY3c3y9sjQ%2B6XPDmQ0gkb0MDsET%2FYKZGImqhEeX4BxlIfWjPwFIw5A4WLHJiMU66QLxonPWMokOb5MVdryIJGd6HsUfCnMToaTfPlXowZ3ucPGHXStFicU5ft7JEhFmzO1k0%2F1UQceUaWSzdCZnvNGveL8LhkX7pGSy3vH%2FbKKJ1MS0tkqlDlB%2BsM6hX2G5et8pnVJT8n1e34R%2BH6LuSI78MEMaXITHn48RWXIK2BviUGG%2B6vVP02%2BP2xer43L9f1AmnD4gV1A3jYi4TU4dF%2FpyPLc8G1S0fY34kqlC4L2aJ4zCjExW4FWrkiEQatmnHozr%2Ff7kykfxxZJYWg4RJZUwEVZLVS1w7oSjn0AoTipTBx0W9dIeIksC5yrCHJS%2FwI4cn25JU2CMkWV8U5s3FbZjylelqdoqlkxCjXIxIjKgIBOO9xrjL2px4MmM4kJ58l5yQsFSXUNbpclhHlic1xuxiCEYNIgcpKZQFompepVS6UY7bCILFRmLbXv9Znfh2yZ74b%2F3UnPAg1ayDkMSBBX7jYWOVlhFIvCf9gHA%2FP9dfJlZv6xo%2FNTLWcZ1YPYpPs%3D&checksum=312703518274f15873459d9a46dfa5eea9601f8f4bce

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Short URL :  https://www.ebay.co.uk/itm/312703518274   😉

Thomas

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RE: Measuring the Temperature at the Nozzle

OMG, that's a HUGE URL...   sorry...   it's an ebay item

RE: Measuring the Temperature at the Nozzle

Thank you so much to share this info. Thats so kind of you.

https://thermostats.me/

RE: Measuring the Temperature at the Nozzle

If you need more information on measuring temperature check out this website on  thermal conductivity. 

RE: Measuring the Temperature at the Nozzle

I use this, and it works well.

RE: Measuring the Temperature at the Nozzle

I tried with a baseline FLIR thermal camera (still expensive, though), which was OK for measuring the nozzle temperature, but not good enough to distinguish the filament from the nozzle.

RE: Measuring the Temperature at the Nozzle

@vojtech-p6

I have the Flir one thermal image camera also, but it's not really good for the Nozzle. It's good for showing the heat distribution on the bed and getting a good idea of heat distribution inside an enclosure, If I didn't already own one I wouldn't buy one for use with my printer, it's been very unnecessary.

The Infrared thermometer has been helpful, they are inexpensive and I would recommend one with adjustable emissivity, you can get a decent one for around $15-30 US.