Solidoodle's new hot end design (Page 2 of 3)

Tomek: thanks for being so helpful.  I've soldered for 45 years, and understand how to do it right.  The bigger challenge is not heating the pins so long that they melt out of the connector.  So, it is literally touch and go.  It seems to be holding now.

You might try this
http://store.qu-bd.com/product.php?id_product=23
It would give you some distance from the hot end to keep the solder joints from failing.

I just got my J-head wired up, which uses a resistor the same way.  I bent the leads at right angles a couple of times to make them point up, but set apart from the PEEK.  Then I cut them shorter and soldered a bit of wire to the leads and then put a connector on the wire.   I wrapped the block in Kapton, cut a hole for the resistor, put it in with thermal grease, then wrapped it in Kapton again. I've also seen a recommendation to use aluminum foil around the resistor to make it fit snugly.

I am wondering why no one is using crimp connectors between the resistor leads and the connector wire?  They will work much better at temperature and if the connectors are again taped (or somehow fixed) to the extruder (strain relief) will not be subject to any force that might pull them apart.

Something like this would work well I would think:
http://www.amazon.com/Non-Insulated-But … uto_text_y

Mine failed during heatup, so if you've managed to extrude something, you're well past where mine failed.

I swapped out the first (dead [high resistance]) new Solidoodle hot end, and put the second new Solidoodle hot end in its place.  It printed for about 3 hours before clogging solidly. This time, the temperature is still fine (200), but I cannot get anything to extrude: I just dig a divot into the filament.

At this point I am at a loss.  Two new hot ends, each of which died (for different reasons) within hours.  I can order a J-Head when they become available.  I have a 12 V heater on order (which I could use to replace the dead resistor in the first hot end).  But all of this just seems totally unreliable, erratic, unpredictable.

Anyone have some advice?

Solidoodle: are you reading any of this?!?

My Jhead from hotends.com is working really well.  The first print I did (filastruder funnel) seemed to have a slightly smoother finish at .3mm than the makergear hotend.   It also heats to 220 in about a minute and keeps a steady temp.  I don't know if its the hotend or thermistor table, but it doesn't overshoot when changing temperatures like the old one did.  It settles on a set temp much quicker.

I'm looking forward to the JHeads.  When I switched from the old Solidoodle hot ends to the new ones, I was given information about how to tell the controller to recalibrate the thermal characteristics of the new hot end.  Before the calibration, the temperatures were all over the place, oscillating plus and minus 15 C; after the recalibration, it snaps to the temperature line.

I think it was 5.  I didn't need to recalibrate the PID, it works out of the box.

Yes, I didn't want to cannibalize my other hotend in case there was a problem.

The melt zone on this one is definately shorter.  When I back the filament out, it takes a lot more reverses to get it clear.

linesman splice...

make the connection mechanical as well as electrical.

I realised this was the problem when my hot end failed, simply because of where it failed, (the solder joint at the hot end)

I received two new hot ends from Solidoodle over the weekend.  I do not yet know whether they work because ... because ... they are now using connectors that do not fit into either the original connectors or even the new wire pairs that they sent with the hot ends.  I guess they did not test these things at all.  I took my trusty XActo knife and clipped the two "teeth" off of the connectors, and then they worked.