Any opinions on the AiXun T3A?

[dreamcat4]

hmm. come to think of it... i am more concerned now that extending the cable does not mess up the tc junction / passing the thermocouple measurements.

since we are adding new metal - metal junctions with soldering this extra terminations in series.

in this event, then keeping the option remain the original gx12-5 connector on the front panel pcb. that is more desirable. as a way to go back to stock configuation. in case there is any such problems. with mis-reading of the temperature.

what i need to remind myself for. is to jog my memory to test for  this in 2 weeks time. after last parts arrives. after doing the mod.

have got the cheap iron thermocouple temperature calibration tester. will need to use it. see if calibration stays the same with / without.

[c0d3z3r0]

I don't think that it has that much influence but yes, you can always recalibrate

[ma_ko]

Hello guys, I have a question. I've been using this station for like a month and it was fine, well it still is, but the sleep function sometimes stops working, it's kinda random and I'm looking for a way to fix it. I noticed there's a missing connection between the the tip and the metal ring on the handle and it's probably the cause of the problem. Sorry I haven't read the thread completely. Did you guys manage to fix the problem?

Sorry for my english, i'm not a native speaker

[c0d3z3r0]

Hello guys, I have a question. I've been using this station for like a month and it was fine, well it still is, but the sleep function sometimes stops working, it's kinda random and I'm looking for a way to fix it. I noticed there's a missing connection between the the tip and the metal ring on the handle and it's probably the cause of the problem. Sorry I haven't read the thread completely. Did you guys manage to fix the problem?

Sorry for my english, i'm not a native speaker

The connection isn't really missing but it's not very solid. The outer connector of the tip only touches that metal ring. When one of both is corroded, the connection becoms unreliable. That probably is the reason, why JBC's original handles now have a silicon gasket [1].

First, I would try if touching the ejector with the tip directly makes it enter sleep mode. If yes, try to clean the tip and metal ring inside the handle. You can also *carefully* roughen both using some fine (400-600 or more) sand paper. However, both are just temporary solutions.

A longer lasting solution would be 1) using that gasket (haven't found any cheaper 3rd party gasket that would fit 8€ for a bit of silicon... wtf) and 2)  somehow solder a tiny wire inside the handle to the metal ring (yeeeeah, that's FUN! I haven't tried.) and connect it to GND.



[1] https://shop.wetec.de/produkte/loettechnik/zubehoer/jbc/92664/jbc-verschlussstopfen

[c099]

How should I properly replace the tip? Do I need to press any button first?

[c099]

The 245 clone tips keep on failing after weeks of use on my T3A. Is it a firmware issue or something else?

[hubi]

8€ for a bit of silicon...

Don't know about Europe, but I see them over here for around that much for a 10-pack.

[c0d3z3r0]

Doesn't surprise me tbh... I use genuine tips

[c0d3z3r0]

8€ for a bit of silicon...

Don't know about Europe, but I see them over here for around that much for a 10-pack.

Hah, maybe it's really a 10-pack and sellers just don't tell in their descriptions 

[dreamcat4]

8€ for a bit of silicon...

Don't know about Europe, but I see them over here for around that much for a 10-pack.

link?

[hubi]

8€ for a bit of silicon...

Don't know about Europe, but I see them over here for around that much for a 10-pack.

link?

Just type "jbc ob2000" into google and you'll get a good number of results, e.g., https://www.tequipment.net/JBC/OB2000/Soldering-Accessories/.

[Andrew LB]

I solved the gasket problem by getting some high temp silicone rubber tubing (two sizes) 10mm OD and 6mm OD from McMaster and one fits inside the other which not only creates a nice seal so fumes don't get inside the handle, but it also lets me hold the iron closer to the tip for better control. The added bonus is i can change tips without turning it off, or cooling down. The silicone is rated to 450'f but it hasn't melted or done anything strange... yet. lol.

The 245 clone tips keep on failing after weeks of use on my T3A. Is it a firmware issue or something else?

Strange. I've been using the curved tip primarily since December and it's perfect.

[dreamcat4]

I solved the gasket problem by getting some high temp silicone rubber tubing (two sizes) 10mm OD and 6mm OD from McMaster and one fits inside the other which not only creates a nice seal...

hi, very interested in this. can you give a more complete specs including the inner diameter and / or mcmaster part numbers?

photo would also be a great help. many thans

[c0d3z3r0]

8€ for a bit of silicon...

Don't know about Europe, but I see them over here for around that much for a 10-pack.

Hah, maybe it's really a 10-pack and sellers just don't tell in their descriptions 

I rechecked. Yes, it's indeed packs of 10

[Dragonisko]

Hi.
I just ordered mine T3A, and im wondering if anyone in uk or europe got spare silicone gasket for t245 handle (jbc ob2000) for sell, was trying to buy it but shipping costs from USA is almost 80$ and the other one i found was around 35$ from germany.

[c0d3z3r0]

Looks like they're restocking... https://www.weidinger.eu/de/p/wl48321

[Dragonisko]

shipping to uk around 120$...

[janoc]

Hello guys, I have a question. I've been using this station for like a month and it was fine, well it still is, but the sleep function sometimes stops working, it's kinda random and I'm looking for a way to fix it. I noticed there's a missing connection between the the tip and the metal ring on the handle and it's probably the cause of the problem. Sorry I haven't read the thread completely. Did you guys manage to fix the problem?

Sorry for my english, i'm not a native speaker

The connection isn't really missing but it's not very solid. The outer connector of the tip only touches that metal ring. When one of both is corroded, the connection becoms unreliable. That probably is the reason, why JBC's original handles now have a silicon gasket [1].

The problem is possibly much simpler. If you are using the "upgraded" stand, then when you open it (2 screws under the front rubber feet), then you will discover that the connection to the handle holder is made only using a crimped eyelet that is threaded on the screw holding the metal piece where the handle rests. The problem is that eyelet is completely loose and does not make a good contact to the screw - and worse, they have put an insulating washer to stop the eyelet from moving around - except they have put it between the eyelet and the metal rest for the handle! 

I have removed the insulating washer and put a normal washer in instead, that seems to have fixed the issue for the time being. But you may want to do a bit more robust fix to attach the wire directly to the metal handle holder instead.

Oh and the power rocker switch on the back of my T3A sometimes doesn't want to turn off - it just doesn't go "click", only flips back and forth. Yay for cheap products made out of cheap parts

[c0d3z3r0]

Hello guys, I have a question. I've been using this station for like a month and it was fine, well it still is, but the sleep function sometimes stops working, it's kinda random and I'm looking for a way to fix it. I noticed there's a missing connection between the the tip and the metal ring on the handle and it's probably the cause of the problem. Sorry I haven't read the thread completely. Did you guys manage to fix the problem?

Sorry for my english, i'm not a native speaker

The connection isn't really missing but it's not very solid. The outer connector of the tip only touches that metal ring. When one of both is corroded, the connection becoms unreliable. That probably is the reason, why JBC's original handles now have a silicon gasket [1].

The problem is possibly much simpler. If you are using the "upgraded" stand, then when you open it (2 screws under the front rubber feet), then you will discover that the connection to the handle holder is made only using a crimped eyelet that is threaded on the screw holding the metal piece where the handle rests. The problem is that eyelet is completely loose and does not make a good contact to the screw - and worse, they have put an insulating washer to stop the eyelet from moving around - except they have put it between the eyelet and the metal rest for the handle! 

I have removed the insulating washer and put a normal washer in instead, that seems to have fixed the issue for the time being. But you may want to do a bit more robust fix to attach the wire directly to the metal handle holder instead.

Oh and the power rocker switch on the back of my T3A sometimes doesn't want to turn off - it just doesn't go "click", only flips back and forth. Yay for cheap products made out of cheap parts

Wow... nice. I had opened the stand when adding my additional tip holder. I my case that connecting was rock solid. So, this might only apply to some people here

[dreamcat4]

Checked here mine is OK too... they made it good.

sleep function sometimes stops working, it's kinda random

Here see in this example photo... the black wire (comes from the black lead)... it is crimped AND soldered to the green wire (which then goes to the metal tip holder).

So check that connection is solid. And then also check the continuity between the green wire and the metal ring holder.

If it is not this issue... then otherwise it might be poor connection inside the handle. Between the outer ground (outer case). And the metal ring.

 

[al777]

Hi folks, just circling back to share the latest and I think, final update to my Aixun T3A unit. Just like before (p.22 of this thread) it's about ESD protection, except now it is for the front connector. While an option to open the unit's front panel and modify the MCU PCB was published already - I thought the less invasive idea may appeal to some. I've placed the protection circuit into a small aluminum enclosure, with a pigtail with GX12-5 on one end going to the T3A base station, and the opposite-gender GX12-5 is on the other end of the enclosure, where T245 handle connects. See the attached photo of the unit in use. I've included an LED and it became surprisingly useful addition - it reflects the PWM power delivery quite well, fading in/out when heater goes active/dormant. To me the unexpected usefulness came from the fact that I can see it in the corner of my eye and it gives a reassuring indication when the tip is really dumping heat into whatever I work on (vs. when you think the tip is touching the solder joint and you are wondering why solder doesn't melt :-) ). Unexpected, but fun :-). Anyhow, schematic is also attached and if you zoom in :-) - you can see which TVSs I chose for this setup, if the font is too small - it is Eaton Bussmann STS321033U202. Hope this helps someone. Have a great day!

[al777]

...adding inside view...

[dreamcat4]

Hi folks, just circling back to share the latest and I think, final update to my Aixun T3A unit. Just like before (p.22 of this thread) it's about ESD protection, except now it is for the front connector. While an option to open the unit's front panel and modify the MCU PCB was published already - I thought the less invasive idea may appeal to some. I've placed the protection circuit into a small aluminum enclosure, with a pigtail with GX12-5 on one end going to the T3A base station, and the opposite-gender GX12-5 is on the other end of the enclosure, where T245 handle connects. See the attached photo of the unit in use. I've included an LED and it became surprisingly useful addition - it reflects the PWM power delivery quite well, fading in/out when heater goes active/dormant. To me the unexpected usefulness came from the fact that I can see it in the corner of my eye and it gives a reassuring indication when the tip is really dumping heat into whatever I work on (vs. when you think the tip is touching the solder joint and you are wondering why solder doesn't melt :-) ). Unexpected, but fun :-). Anyhow, schematic is also attached and if you zoom in :-) - you can see which TVSs I chose for this setup, if the font is too small - it is Eaton Bussmann STS321033U202. Hope this helps someone. Have a great day!

those are some very helpful / useful mods. and well documented. thank you!!

and that tvs diode did not come up in my parts search for some reason. had instead found some other brands (but similar equivalent choice)... so will be adding this one to my shortlist of "the more desirable" tvs diodes to get. maybe will also compare them later on.

in terms of using your mods... i'm going to want to use them. however not 'as is' will need to adapt and change them somewhat. but not the essence of what they are. i.e. the actual function. although having said that i am actually ditching pins 1 and 3 completely for my own specific mods (which also makes certain things a lot simpler to deal with).

however one question i am left wondering is those 1uf caps what the purpose is for? also the d1 diode? why are those needed or desirable here?

[al777]

Capacitors are an additional layer of ESD protection, together with resistors they comprise a low-pass RC filter, further smooting the (remaining) ESD spike. TVSs are clamping down from very high ESD voltage to still high-ish voltage (for the logical level inputs), the RC filter is "outlaying" / spreading the energy over time, making it go from _|_  to _----_. In other words - a companion to TVS. Cannot do that for the thermocouple input as inline resistance may throw off the measurement, so there it's only a cap parallel to TVS, serving as a parallel shunt for ESD energy to flow through to the ground. In fact in some applications - ceramic capacitors are the only ESD protection used, I've seen it in automotive ECU designs. There are papers written on that topic (caps vs ESD, longevity of various dielectrics etc.). It's a legit way to treat ESD injection, obviously not as effective as fast acting TVSs.

The anti-parallel diode is to protect LED from the reverse voltage spikes which may be generated by somewhat inductive load (heaters may still have inside a thin nichrome or similar wire, wound in a pattern giving it tangible inductance). PWM is essentially fast-switching the load on and off, if that load is inductive - well, that's how ignition works in ICE engines :-).

[janoc]

Checked here mine is OK too... they made it good.

sleep function sometimes stops working, it's kinda random

Here see in this example photo... the black wire (comes from the black lead)... it is crimped AND soldered to the green wire (which then goes to the metal tip holder).

So check that connection is solid. And then also check the continuity between the green wire and the metal ring holder.

If it is not this issue... then otherwise it might be poor connection inside the handle. Between the outer ground (outer case). And the metal ring.

 

That actually looks quite different than my stand - I don't have any connector there and there is only a single thin wire with a grommet coming out of the center of the back. That wire is terminated to the screw where the eyelet is in the photo and the green wire has another eyelet on the side, touching the metal holder for the soldering iron. That's where it went bad on mine.