Nylon layer adhesion problem

I am posting the same email I just sent to taulman about this but thought I would ask here as well.

Hello,

I just got my order in yesterday and was eager to try it out. I started with the 645 3mm nylon (I also ordered the 618).

I had a bit of a hard time starting out, I could not get it to stick down, tried different materials including blue tape, PET film and the backside of copper clad PC board which is fiberglass. It's similar to the Phenolic that RichRap uses and I had some on hand.

I finally got it to stick by printing very slowly (20mm sec) using my .50 nozzle. The .35 that I normally use for ABS just seemed to small as almost nothing came out of it.

I tried printing at 235c and 240c (240c seemed to work) so I printed a coin that I have that has letters in it. The letters were a little wonky (not nice and tight) but none the less it printed.

When I pulled it off the PC board (which was very easy) I touched one of the letters and it came off easily, so I tried another. Before you know it all the letters where laying on my desk and not attached.

So I then tried and was able to fairly easily peel apart the layers of the coin. So there seems to be a serious adhesion issue from layer to layer

I printed with a .50 nozzle, .25mm layer height 240c temp and 20mm second speed across the board.

So you gave any ideas what I might be doing wrong?

Thanks to Taulman for getting back to me at 11:10pm (just minutes after I emailed them). I found out it's lack of heat.

Started printing at 265c (according to my machine) and it sticks very well now. I have on order an accurate digital thermometer so I can see if my readings are off or not.

Thanks for sharing your experience.
I use the PID with Thermocouple temperature control from Ebay to control my hot end and heated bed. The temperature seems to agree with a infrared temperature and another thermo couple reader. I then stick the regular 100K thermistor that everyone is using to my hotend just to see a graph from the GUI, and I can see the temperature reported by Marlin is not always the same as the reading from the PID controller. In some temperature ranges, the reading is off by 1 or 2*C but some other ranges the reading can be as different as 10*C. Good accurate temperature gun is expensive and I don't have one, so it's also quite puzzling to see the discrepancy. But I'm leaning toward to trusting the reading from the PID & Thermocouples.