Nozzle unclogging/unjamming temperature?

Hi,
I've just switched to ABS for printing a new x-carriage + extruder.
During testing I get curly extrusion, which in my experience is a symptom of debris in the nozzle, and a future jam waiting to happen.

I've cleaned out my nozzle using the "plug" technique before and it has worked very well.
The idea is to start at normal extrusion temperature, then lower to let the plastic form a partially hard plug in the nozzle. Then pull gently until the plug lets go, and the plug takes the debris with it.

My problem is that I've forgot the suitable temperature ranges, and I lost my notes on it in a recent move.

My google-fu seems to be insufficient right now (and I remember having a very hard time finding it last time too).

Does anyone have a good ballpark temperature range? Ideally for both ABS and PLA.

(I did try a few values around 100 C for ABS, but no joy yet)

/Andreas

For PLA, I set to 60*C then back the plug out as soon as it reaches that temp (it will overshoot a fair bit). For ABS, I use 80*C. Sometimes the filament breaks and the plug doesn't get pulled out, but most of the time I am successful. Note that this is with the E3D hot end.

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Many thanks, I'll try those temps when I get back from work today.
I'm using a J-head IVB, Faberdashery PLA, and Form Futura ABS.
I'll report back with results, I suppose the brand of plastic is a big factor in the equation, but those temps will probably help a lot.

/Andreas

Well just to report back, I couldn't find any temperature to work with the plug-type unclogging.
I know I've done it before with great success, but I think I must have left a tiny gap in the J-head when i assembled it last time. The plug sticks in the gap and when I pull on the filament, it snaps just after the ridge formed in the gap. I can see slight ridging if I up the temperature a bit more making the plug squishy.

Anyhow, I seem to have managed to unclog using a slightly different technique. I ran the hotend at around 140-150, which melted the PLA but kept the ABS squishy. I then poked repeatedly with some ABS to "fish" out the remaining PLA and any debris with it. Not as super clean as the plug method, but it seems to have worked, I no longer get squiggly extrusion with ABS. I just need to verify with the extruder fully assembled, but I'm confident it's going to work with the motor as well (I disassembled the drive gear to get some clearence for a K temp probe).

/Andreas

What I do, is start from cold, and set it to the standard extrusion temperature. As it heats up, firmly pull on the filament. Usually at some temperature it will suddenly release, and you get your plug. Sometimes it breaks though. It helps if when you were last at extrusion temperature, you fed some filament out, so that a retraction was not the last thing it did, as this can create a thinner filament section in the middle that is more likely to break.

Mike