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Cefiar
Where did you get the thermistor that is in the hot end you have? If you can find the correct table for it (or calculate it) then you'll get much better results.
You may find that the calibration is still off (eg: 240 when it's say 200) and that your temp readings are not as accurate as you'd like.
Cefiar, I was using the correct thermistor table according to the manufacturer specs, (#1 on Marlin for EPCOS 100K). I used the same table for the heatbed, which is accurate. I ended up making a copy of the table 1, assigning a new variable to it, and using the new (modified table 1) for the hotend, and the standard #1 table for the bed.
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NoobMan
You mentioned that you bought the extruder used. Maybe the guy before used it for abs, and was not fully cleaned, so it needs 240c to melt those abs bits in order to extrude, otherwise at lower temp the abs might block the nozzle orrifice. This could be a plausible scenario or explanation, if it needs a real 240c for extrusion. You mentioned you use black and purple pla, if it would of been clear transparent pla maybe it would of showed some impurities inside. Or you can perhaps try ask the previous owner if it printed abs with it.
Also i would try to give some insulation to hotend. My personal preferred method is to cover the hotend in a high temp silicon. This can be bought at gas stations or auto parts shop and it is "silicon gasket" for motor block or evacuation galleries and it is stable to temps up to 400C and is cheap, and has fairly good adhesion to metal surfaces. It aslo makes some bad smell first time its heated up, but after that it gets cured and its fine and odorless afterwards.
NoobMan, that is definitely another possibility. I'm not sure if the extruder was ever "used". As far as I am concerned, the guy was building the printer, and was about halfway through assembling everything when he sold it. Is there a good way to ensure the nozzle is cleaned entirely? I have checked the hotend heating block set screw at both ambient temp and operating temp to ensure it is tight (just incase the heater block is expanding and losing contact area). I have noticed when taking the temperature at various points, that it does indeed loose heat fast in relation to distance from the hotend which tells me it is poor at conducting heat. The base plate by the extruder is a tolerable temperature where I'm not worried about it melting the components (52C on the base plate, while extruding at 240C).
The high temp silicone sounds like a great idea, I may have to try that. Yesterday when extruding successfully around 240C, I kept the thermometer on the hotend block to monitor the temps. It did not seem like it was losing heat as suspected since it maintained the desired temperature, but that doesn't mean it wasn't internally.
As far as a fan, should I look into mounting one near the nozzle? I am still confused as to why the manufacturer says "PLA 220-240C, fan is highly suggested", whereas other materials are recommended to be extruded at up to 280C, without a fan. What exactly am I worried about where I need a fan?
If a new, nicer working hot end isn't much, I may just opt for that. As I said, I have been able to extrude material now, but the temps/requirement for a fan seems odd considering I don't see that on other setups accomplishing the same thing.
All of the feedback and support is awesome, and is greatly appreciated! Thank you!
-Pat