(A) 1322/1323 - an updated version of the heating element for the Lukey 702 soldering iron, now in metal!

Good day, dear readers.
In this review, the repair of the soldering iron will be reviewed.Lukey 702 station, with the installation of an unusual heating element (A) 1322/1323. This heater is an adaptation of (A) 1323 in the form factor (A) 1322, and, at the moment, only four sellers have seen it on AliExpress. The whole process from the beginning of the problem to its solution is commented on and provided with the necessary photographs, which allow to obtain enough information necessary to form a decision on the purchase of this product.

All of these heating elements arecontinuation of the development of clone Hakko A1321. And despite the fact that the company Hakko does not release any of these models, some sellers remove the letter from the name in order to prevent the likelihood of such associations. For this reason, when a particular seller mentions goods, I use the seller’s spelling variant (with or without the letter “A”), and otherwise, when the model is generally mentioned, the letter is enclosed in brackets, implying both spellings at the same time.
The station Lukey 702 has long been for manyworkhorse, and all of it, like any other "popular" tool, the disadvantages are well studied and well known. One of the main disadvantages is the failure of the heating element. The Internet is replete with complaints of similar problems, and often in the forums or in the comments you can see how some users even deserve the longevity of its use, or vice versa - the number of burned copies during the life of the station.
My copy has worked faithfully with a dozenyears and could have probably served further, but this spring I first needed a thinner sting and several replacements were enough to finish off the already “tired” heating element. Several times I managed to remove the number “713” from the display, selecting the nut tightening force, but by the beginning of the summer it had settled there permanently. The station required repair ...
In his city, despite the populationabout half a million people, the heating element could not be found - it was only in the composition of the soldering iron for ~ 700 rubles. Search for various options on AliExpress with the keyword "lukey 702", for some reason did not give any results. I had to ask Google for help ...
The search engine immediately found me a colleague in misfortuneand sent for review from sav13, describing a similar problem. Despite the fact that links to products no longer worked, they suggested the correct keywords from which you could create a search query, while photos and specifications helped to reduce the number of results found. Thus it was possible to establish that the heaters (A) 1322 are required for the Lukey 702.
When, among a dozen searches anda few hundred of the results found, my opinion caught a couple of times on the heating elements that are shiny with metal, I decided to study these proposals in more detail and, as it turned out, for good reason.
What are they like? According to the sellers, this is a version of the heater (A) 1323, characterized by an increased lifetime (and appearance), in a standard design (A) 1322. Sounds like a solution to our problem, doesn't it?
I stopped my choice on the store offer AiyimaElectrical Storewhich, it seemed to me, is the main distributor and, probably, the manufacturer of this product.
Parcel Among the free shipping methods, the seller offered my preferred option - ePacket.
The track number was assigned during the day, on the 6th day the parcel arrived at the seller’s post office, and at 21 it arrived at the place of delivery.
Tracking


The seller did not stint on the packaging and carefully packed the contents, minimizing the risk of damage upon delivery.
In a standard gray plastic bagthere was a bundle, tied with adhesive tape in length and width. (In the photo, the adhesive tape was removed, because it created glare from the lighting. A soldering iron was added to demonstrate the dimensions of the package.)
Inside the packaging material was a modest bag with 3 heating elements.
Heating element Aiyima 1322/1323
Specifications:
  • Brand: Aiyima;
  • Operating voltage: 24 V;
  • Power consumption: 50 W;
  • Thermocouple resistance: 2 ohm;
  • Compatibility: 936A soldering station and its analogues.

I could not check the resistance of the thermocouple- and the Mastech MS8221C multimeter and the LCR-T4 tester together showed ~ 0.7 Ohm for any polarity (for the remaining two elements, the result was the same). But the resistance of the heater was determined - 10.0 ohms.According to Ohm’s law, the calculated current is 2.4 A, and the power is 57.6 W, which is 15% higher than the stated.
Pinout pinouts:

  • Two red wires - heating element;
  • Blue wire - positive thermocouple contact;
  • The yellow wire is the negative contact of the thermocouple.

Conclusions made in different lengths to simplify the replacement process and prevent erroneous connection.
The only thing that initially raises the question isincreased length of stripped yellow wire. According to information from other vendors, this is done for compatibility with rare instances of stations with inverted polarity of the thermocouple. Enough prudent move.
Replacing the heating element of the Lukey 702 soldering iron. Now it’s time to start the actual replacement ...
To begin, try on a new heating element.The length of the pins completely coincides with the holes on the board.
Now look at the heating part.Their lengths also completely coincide.
Vypayal faulty element and make measurements of diameters.The results are almost the same - there should be no deterioration in heat transfer.
Compare at the same time and the tips of the heating part.There is a difference, but one can only guess about its real impact on the operation.
Now solder the item in its place.In case you have the same PCB inthe soldering iron handle, but the wires of the cord and the leads of the heating element are soldered to the corresponding tracks not through the outermost holes to them, then you have to fix it, because the length of the findings may not be enough. As a rule, such a modification is made immediately after the purchase of the station or the replacement of the soldering iron, since it corrects a common problem with an insufficient length of the heating element, allowing the heat source to be shifted closer to the tip of the sting and improving heat transfer.
We shorten the excessive length of the leads, wash the soldering places first with alcohol, and then with acetone. If necessary, blot excess liquid with a paper towel and / or blow-dry.
Now we collect the soldering iron, but do not put on the nut fixing the sting.
If you change the heating element with the same amount of overhang, then before and after the replacement there should be a small gap between the sleeve and the sting base.Now we put the nut, tightening it with the usual effort, and then remove it again and look at the change in the gap.In my case, the gap was gone. The reason for this is that the conclusions of the new heating element are slightly thicker and shorter than those of the old one, therefore the former spring effect is no longer achieved.
This will not affect the performance of the soldering iron.
After completing all the work, it would be nice to check the resulting result.
For this, I set up my usual workingsoldering iron temperature, hung a large drop of solder on the tip of the tip and inserted a thermometer from a multimeter lightly oiled with high-temperature silicone grease.The temperature deviation was only 4 ° C, the stability of indications for ~ 5 minutes of the test remained within ± 3 ° C.
Conclusion Now it’s time to sum up our narrative and note the pros and cons of its hero, the heating element (A) 1322/1323.
Pros:

  • Increased service life (according to the sellers);
  • Increased mechanical strength;
  • Convenience of replacement (different length of the terminals eliminates installation errors)
  • Accuracy and stability of heating.

Minuses:

  • Low prevalence and, as a result, fame;
  • Higher cost (~ 2 times).

For this, let me take my leave and wish you and your instrument a long life!