Aixun T3A overshooting with JBC tip

[tony359]

Hi all,

I've got an Aixun 3TA and I've been experimenting a bit.
I've noticed that the station tends to overshoot a lot but mainly only with a genuine JBC tip I purchased. When sitting on the thermometer, the power level sits at 0-3% as you'd expect then suddenly jumps to 100% for a moment and the temperature jumps to +40C above the previous recorded temperature. The temp then slowly drops down to the setpoint again. The display - of course! - doesn't record that!

Is that kind of expected for whatever reason?

[mastershake]

what firmware? i know one of the older ones used to do this for me. i cant remember which one it was but it did say something about it in the firmware notes if i remember right https://aixun-updates.github.io

[tony359]

latest 1.34. Yes there is a note in the changelog about overshooting but that's an older version.

I made a video of the issue here: https://youtu.be/z6oj99W5PH0

I'm not using a wet sponge or anything, the tip is just sitting on the probe.

I contacted Axiun, they replied that that behaviour is intentional to give the tip a little boost when the solder is being melted. I admit that sitting on a thermometer is not a "real world" situation as the probe doesn't have any mass there and you'd never keep the tip sitting on a solder joint for so much time.
In real world you place the tip on a joint, the circuit detects a temperature drop and it sends a short burst to the heating element to quickly counteract that without waiting for feedback. However if there is no mass where to dump that energy, you then measure an overshoot.

I suppose that if you measured on an actual joint, you wouldn't see that.

Still, I would expect the tip to be able to keep a stable set temperature if not doing anything and I do not observe the same behaviour with the Axiun kinfe tip - which is smaller than the JBC.

Aixun further commented on my query and stated that being a "non-Axiun" tip, "there maybe some little unstable factors occured during soldering". Uhm...

What is the general consensus on Axiun tips? Haven't tested mine enough and JBCs are so very expensive!

[c0d3z3r0]

What is the general consensus on Axiun tips? Haven't tested mine enough and JBCs are so very expensive!

I have both Aixun and genuine JBC tips and working with JBC tips is waaaaaaaay better than Aixun

[tony359]

As I suspected. When I got my Aoyue years ago it was UNUSABLE with Aoyue tips. It became a massive different iron with genuine Hakko tips.

I'll keep buying JBC tips, thanks for the hint.

Also thanks you and everybody else for answering my question on the other larger T3A thread. Just to close this thread, which I also have misspelled, the issue is with FW 1.34. Reverting to 1.33 fixed it.

[thm_w]

Out of curiosity whats the tip geometry being tested here?
Is it possible they've optimized for a larger tip size and didn't test with something small that might see a larger overshoot.

I believe JBC might have some more intelligence in terms of detecting tip type/mass on first power up, but I could be wrong.

[slavoy]

The initial overshoot is deliberately programmed into the software. However, the temperature should stabilize after a short while and fluctuate within 1-2 degrees. Unfortunately, I no longer have that station, and I don't remember which software version I had, but it worked perfectly for me regardless of whether the tip was JBC or Chinese-made.

//
Now I've noticed that reverting to version 1.33 solved the issue. Apparently, there's something wrong with the new software, and it's worth informing AiXun.

[tony359]

Out of curiosity whats the tip geometry being tested here?
Is it possible they've optimized for a larger tip size and didn't test with something small that might see a larger overshoot.

I believe JBC might have some more intelligence in terms of detecting tip type/mass on first power up, but I could be wrong.

This is a JBC 2.2x1mm chisel tip. Actually I experienced that with the larger JBC and not with the smalle "knife" tip from Aixun - I thought the same but in theory a larger tip would absorb those spikes more easily in theory.

I'm told that with 245 there is no intelligence, the station doesn't know which is which. But I do remember watching a review (SDG electronics?) mentioning that the reason why a particular tip was not getting 100% of power it because it was being recognised as "small" and as such not able to take the whole 100% from the station.

The initial overshoot is deliberately programmed into the software. However, the temperature should stabilize after a short while and fluctuate within 1-2 degrees. Unfortunately, I no longer have that station, and I don't remember which software version I had, but it worked perfectly for me regardless of whether the tip was JBC or Chinese-made.

//
Now I've noticed that reverting to version 1.33 solved the issue. Apparently, there's something wrong with the new software, and it's worth informing AiXun.

With 1.33 there is no overshoot, not even when it starts from cold or when I put a wet sponge on the tip!
Aixun "BS" me with some marketing stuff so I am not sure they would be interested in hearing my feedback to be honest.

[Marcel]

Had the same problem with 1.35. Just wanted to downgrade to 1.33, but saw 1.56. With 1.56 the overshooting problem seems to be fixed.