Author Topic: EEVblog #1065 - Soldering Iron Power Delivery Explained  (Read 2374 times)

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Offline EEVblog

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EEVblog #1065 - Soldering Iron Power Delivery Explained
« on: March 18, 2018, 10:12:01 am »
A further clarification to the previous video on the Hakko FX-888D vs the JBC direct heat CD-2B soldering station. And the differences between applied power, tip design, sensor design, control loop design, and power delivery to a ground plane.
Power measurements and DaveCAD explanations.

https://kit.com/EEVblog/soldering-equipment

« Last Edit: March 18, 2018, 11:53:34 am by EEVblog »
 

Offline Bud

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #1 on: March 18, 2018, 10:18:25 am »
Is it a right link to the video? I am asked to sign in  :-//
 
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Offline EEVblog

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #2 on: March 18, 2018, 11:54:17 am »
Is it a right link to the video? I am asked to sign in  :-//

The new Youtube video manager defaults to the edit video link and not the public link, I copied the wrong one. Fixed.
 
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Offline Bud

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #3 on: March 18, 2018, 03:04:33 pm »
I was terrified by the way the Agilent U1733C handheld was used in the setup    :scared:
 

Online wilfred

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #4 on: March 18, 2018, 05:05:28 pm »
Skin effect. Now where have I heard that before?
 

Online blueskull

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #5 on: March 18, 2018, 05:21:06 pm »
I was terrified by the way the Agilent U1733C handheld was used in the setup    :scared:

A message to GAS/TEA people: any equipment will have a chance to get used. Collect them!
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Online BravoV

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #6 on: March 18, 2018, 08:17:22 pm »
My Hakko heater element is a celebrity now.  ;D

Its from my old thread when discussing the topic about "fake vs genuine" Hakko 936 parts, like the heater -> Here , and the tip -> Here

Example photo of genuine vs fake, top is genuine one, while last two are dodgy ones.

Click to enlarge picture.
« Last Edit: March 18, 2018, 08:20:42 pm by BravoV »
 
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Offline TuxKey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #7 on: March 18, 2018, 10:16:20 pm »
My Hakko heater element is a celebrity now.  ;D

Its from my old thread when discussing the topic about "fake vs genuine" Hakko 936 parts, like the heater -> Here , and the tip -> Here

Example photo of genuine vs fake, top is genuine one, while last two are dodgy ones.

Click to enlarge picture.


will definitely read that post thanks.. i came across a lot of alternative parts even sold here in The Netherlands.. And it's always nice to know your not only paying for the brand name but real quality and most likely better quality control.
 

Offline mancausoft

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #8 on: March 19, 2018, 01:25:36 am »
I was thinking... Is it possible to adapt the new tips to an old station? i mean a handle stick for new tips.
the tecnology inside is the same: resistence and sensors... if the sensor is the same...

it could be useful to exchange an old-style handle with a new style in the same station ... the old tips are cheaper, and they are great for dirty jobs, the new ones can be used for more precise jobs

Offline gearshredder

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #9 on: March 19, 2018, 01:48:46 am »
The metcal fanboy in me has been satisfied lol. Good video!
 

Online langwadt

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #10 on: March 19, 2018, 02:26:48 am »
Surprisingly the sloppy fit between the heater and tip, does it bottom out in the tip so at least the sensor end has a good connection to the tip?

Some +20 years ago I build a temperature controlled iron from a kit, it measured temperature by measuring the resistance
of the heating element at every zero crossing, great idea if it was the temperature of the heating element you were trying to control...
 

Offline TuxKey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #11 on: March 19, 2018, 02:29:10 am »
i just contacted Aoyue eu. And told them about the nice EEVblog coverage related to soldering technologies.
In my opinion the best if not the only in depth / informative series on soldering..  :-+ and more to come  :)

So i told them the only thing missing is in the comparison is an Aoyue product and that i couldn't find any reviews of their soldering iron with the new tech. like the 2901 and the digital 2900....
Asking them if they would consider sending one to David for review...
Will see what their answer is  ;D

for anyone wondering to what device i'm referring to:
http://www.aoyue.eu/aoyue-soldering-hotair-rework-desoldering-station-preheater-repairing/aoyue-adjustable-digital-station-lead-free-soldering-iron/aoyue-int2900-digital-lead-free-soldering-station-smd-soldering-iron-wq-serie.html

 
 

Offline gearshredder

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #12 on: March 19, 2018, 02:47:58 am »
I was thinking... Is it possible to adapt the new tips to an old station? i mean a handle stick for new tips.
the tecnology inside is the same: resistence and sensors... if the sensor is the same...

it could be useful to exchange an old-style handle with a new style in the same station ... the old tips are cheaper, and they are great for dirty jobs, the new ones can be used for more precise jobs

Make a new thread about it. Match heater resistance with a station with same thermocouple and an easy way to calibrate. Temperature may over or undershoot with the new style because the response is different.
 

Online BravoV

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #13 on: March 19, 2018, 03:28:53 am »
i just contacted Aoyue eu. And told them about the nice EEVblog coverage related to soldering technologies.
In my opinion the best if not the only in depth / informative series on soldering..  :-+ and more to come  :)

So i told them the only thing missing is in the comparison is an Aoyue product and that i couldn't find any reviews of their soldering iron with the new tech. like the 2901 and the digital 2900....
Asking them if they would consider sending one to David for review...
Will see what their answer is  ;D

for anyone wondering to what device i'm referring to:
http://www.aoyue.eu/aoyue-soldering-hotair-rework-desoldering-station-preheater-repairing/aoyue-adjustable-digital-station-lead-free-soldering-iron/aoyue-int2900-digital-lead-free-soldering-station-smd-soldering-iron-wq-serie.html

The real deal is how the tip was built + fit into the heater rod "optimally".

Aoyue, Quick and those Chinese soldering iron manufacturers are basically started their business by cloning Hakko 936.

Until nowadays, I don't see many reviewers review the tip technology involved.

Say using FX-888D (same heater & tip as Hakko 936), using the real tip vs dodgy one is pretty obvious, don't need to scientifically test them, you can instantly feel the difference between genuine tip vs 1 dollar tip.

As above close up photos, the genuine one has a proper copper insert or maybe coating ? While the 2nd dodgy one, the hole is off center and has a tiny crack (if you look carefully), while the 3rd one is basically hopeless, its made from steel with no copper inside what so ever.

 
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Online hli

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #14 on: March 19, 2018, 05:27:29 am »
When using a "circuit equivalent" of the solder iron to explain the heat transfer, wouldn't it be better to model the air gap between heater and tip as additional capacitance? After all, when applying constant heat with the cartridge, the tip will react to it with a delay. I think this also better explains the time-lag of temperature regulation.
 

Offline stranger

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #15 on: March 19, 2018, 05:34:17 am »
TuxKey, I’ve been using Aouye 2900 since 2010, bought in the UK from an established channel, as were the tips. I’ve a suspicion Aoyue is moving forward in a different direction to the 2900. Years ago I read somewhere a claim the 2900 was based on a Hakko design. The tips are not  mechanically compatible with the Hakko T12 tips, lacking the ridge that the Hakko ones have half way up the shaft.

I’ve used two Aoyue 2900, they have been value for money but not without issues, like others the firmware is not totally honest on the instantaneous tip temperature. The Aoyue iron I don’t have access to now would very occasionally ‘crash’ requiring a power cycle.
The bits only have two connections despite some having a third ring. I did not expect the variation in the cold resistance the tips, I have a suspicion some were intended for a different product, most are about 8 ohm a few 11 ohms, but one is 6 ohms. Hakko tips seem to be 8 ohm +/-10%.

The Aoyue firmware I’ve seen lacks a timeout if its unused for a while, at least one person has written their own code.

I got interested in increasing the power to speed up the warm up and recovery, its not running hotter just getting to temp faster and even better for ground planes. Ended up running it up to about 160W, the test software is labVIEW, external PSU and hardware. There is still a time constant limitation in the Aoyue Tips that I’ve not explored, doubling the available power was a bit disappointing. I’d need to dissect the tips and look at the thermal design of how the coils (?) are wound etc.

The Bakon BK950D appears to use clones of the Hakko T12 tips rather than the Aoyue:

http://www.eevblog.com/forum/chat/bakon-bk950d-soldering-station-my-opinion!!/
 
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Offline screwbreaker

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #16 on: March 19, 2018, 07:21:46 am »
Also Weller has an active stand to reduce the tip temperature and increase the tips longevity. They call this function "Stop+Go". I think is the standard iron stand for high end models. For low end solutions is sold separately, and it is really expensive.
https://www.weller.de/en/Weller--Products--Product-details.html?article_id=D0356795001379336401A118003#{%22string%22:%22%22,%22current_site%22:%22weller%22,%22current_brand%22:%22Weller%22}

I don't know if it is available also for the WE 1010.

Also PACE has a solution like this.
https://www.paceworldwide.com/products/accessories/instantsetback-cubby
 

Offline ejeffrey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #17 on: March 19, 2018, 07:50:55 am »
When using a "circuit equivalent" of the solder iron to explain the heat transfer, wouldn't it be better to model the air gap between heater and tip as additional capacitance? After all, when applying constant heat with the cartridge, the tip will react to it with a delay. I think this also better explains the time-lag of temperature regulation.

The model dave drew is incomplete and only for illustrative purposes (i.e., he didn't have time to build it to scale or paint it).

The resistance is sufficient to explain why the tip can be cooler than the readout temperature.  A capacitance by itself wouldn't do.  A capacitance represents the thermal mass of the components such as the heater or the tip.  That can capture the ability of the tip to store heat and the recovery time after you remove the iron before it can heat back up.

You also need resistances to "ground" to represent the heat loss to the surroundings and also the heat load of the soldering joint.  Without that, the circuit Dave drew doesn't even have a loop.
 

Offline crispus

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #18 on: March 19, 2018, 08:06:33 am »
Isn't there any high temperature thermally conductive paste to transform this "old" technology into the new one?
I know I'm numskull, but I look around me and I feel better.
 

Offline EEVblog

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #19 on: March 19, 2018, 09:16:40 am »
Isn't there any high temperature thermally conductive paste to transform this "old" technology into the new one?

Maybe, but if there was wouldn't the manufacturers be using it or offering it?
Cue the conspiracy theorists about "Big Iron" and how they are protecting the market for their more expensive irons  ;D
 

Online Gyro

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #20 on: March 19, 2018, 09:44:18 am »
Isn't there any high temperature thermally conductive paste to transform this "old" technology into the new one?

I tried Copper anti-sieze brake grease on an Atten 938D. It's rated for the temperature, but fumes a lot first use and tends to extrude down between the sleeve an the unheated part of the element.

The other thing I found was that there was enough space between the element and tip to accept a thin single layer of Copper foil (screening foil from CT100 coax). It did improve thermal performance a bit but it made it awkward to change tips. The foil would disintegrate quickly, implying that the element and foil were getting an awful lot hotter than the tip. The Atten is now relegated to a high shelf.
Chris

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Offline ejeffrey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #21 on: March 19, 2018, 02:39:26 pm »
To make it a lot better, I imagine you either need some conductive goop like Gyro's anti-seize, or to permanently bond the tip to the heater cartridge with something like silver epoxy.  This would make tip changes annoying at best.

No matter how well you thermally connect the tip to the heater, I think it still wouldn't be as good as a system designed around an integral heater/tip, and it still wouldn't have the features like auto-sleep that direct heat stations typically come with.

So yeah, if you want to eke out a bit more performance out of the iron you have, I wouldn't be surprised if you can do this.  But I don't think you are going to equal or replace the commercially available direct heat irons.
 

Online hli

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #22 on: March 19, 2018, 08:20:43 pm »
The resistance is sufficient to explain why the tip can be cooler than the readout temperature.  A capacitance by itself wouldn't do.  A capacitance represents the thermal mass of the components such as the heater or the tip.  That can capture the ability of the tip to store heat and the recovery time after you remove the iron before it can heat back up.
With a purely "resistive" model, the tip would always be colder than the temperature at the point of measurement, by a fixed (or maybe proportional) amount. I understand that. This can be handled by defining an offset temperature. But it does not explain the delay in regulation, and why the Hakko does not go into full-power mode when the temperature drops too low (which it should when soldering on a big ground plane).
 

Online BravoV

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #23 on: March 19, 2018, 08:26:10 pm »
The resistance is sufficient to explain why the tip can be cooler than the readout temperature.  A capacitance by itself wouldn't do.  A capacitance represents the thermal mass of the components such as the heater or the tip.  That can capture the ability of the tip to store heat and the recovery time after you remove the iron before it can heat back up.
With a purely "resistive" model, the tip would always be colder than the temperature at the point of measurement, by a fixed (or maybe proportional) amount. I understand that. This can be handled by defining an offset temperature. But it does not explain the delay in regulation, and why the Hakko does not go into full-power mode when the temperature drops too low (which it should when soldering on a big ground plane).

Overshoot problem maybe ?
 

Offline FloFo

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #24 on: March 19, 2018, 08:36:21 pm »
The resistance is sufficient to explain why the tip can be cooler than the readout temperature.  A capacitance by itself wouldn't do.  A capacitance represents the thermal mass of the components such as the heater or the tip.  That can capture the ability of the tip to store heat and the recovery time after you remove the iron before it can heat back up.
With a purely "resistive" model, the tip would always be colder than the temperature at the point of measurement, by a fixed (or maybe proportional) amount. I understand that. This can be handled by defining an offset temperature. But it does not explain the delay in regulation, and why the Hakko does not go into full-power mode when the temperature drops too low (which it should when soldering on a big ground plane).
It's not a fixed amount, but the amount is dependet of the thermal current. When you tip touches the wet sponge or a ground plane, you have a huge "current", giving only a small additional temperature drop between heater and sensor (due to small thermal resistance), but a huge drop between sensor and tip due to the big resistance of the airgap. This means that the controll loop still sees an accaptable temperature and doesn't go to full heat while the tips gets quite cold. The control loop still manages to keep the sensor at the desired temperature with occasional heats, so it doesn't see the need for more heating.
 
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Offline TuxKey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #25 on: March 19, 2018, 11:50:15 pm »
TuxKey, I’ve been using Aouye 2900 since 2010, bought in the UK from an established channel, as were the tips. I’ve a suspicion Aoyue is moving forward in a different direction to the 2900. Years ago I read somewhere a claim the 2900 was based on a Hakko design. The tips are not  mechanically compatible with the Hakko T12 tips, lacking the ridge that the Hakko ones have half way up the shaft.

I’ve used two Aoyue 2900, they have been value for money but not without issues, like others the firmware is not totally honest on the instantaneous tip temperature. The Aoyue iron I don’t have access to now would very occasionally ‘crash’ requiring a power cycle.
The bits only have two connections despite some having a third ring. I did not expect the variation in the cold resistance the tips, I have a suspicion some were intended for a different product, most are about 8 ohm a few 11 ohms, but one is 6 ohms. Hakko tips seem to be 8 ohm +/-10%.

The Aoyue firmware I’ve seen lacks a timeout if its unused for a while, at least one person has written their own code.

I got interested in increasing the power to speed up the warm up and recovery, its not running hotter just getting to temp faster and even better for ground planes. Ended up running it up to about 160W, the test software is labVIEW, external PSU and hardware. There is still a time constant limitation in the Aoyue Tips that I’ve not explored, doubling the available power was a bit disappointing. I’d need to dissect the tips and look at the thermal design of how the coils (?) are wound etc.

The Bakon BK950D appears to use clones of the Hakko T12 tips rather than the Aoyue:

http://www.eevblog.com/forum/chat/bakon-bk950d-soldering-station-my-opinion!!/

Reading your experience with the Aouye. It seems like my idea of Chinese targeted hardware is 90% there using the so called new technologies but messing up the last tiny but important tidbits...
So i'm better of getting a so called older tech Hakko FX-888D and a Hakko desoldering gun package from Batterfly vs a setup that requires fiddling.. The TS-100 seems to be of better construction Macro Reps has an awsome teardown of this small marvel btw copper connection inside.. have a look..
 
 

Offline TuxKey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #26 on: March 19, 2018, 11:58:51 pm »
i just contacted Aoyue eu. And told them about the nice EEVblog coverage related to soldering technologies.
In my opinion the best if not the only in depth / informative series on soldering..  :-+ and more to come  :)

So i told them the only thing missing is in the comparison is an Aoyue product and that i couldn't find any reviews of their soldering iron with the new tech. like the 2901 and the digital 2900....
Asking them if they would consider sending one to David for review...
Will see what their answer is  ;D

for anyone wondering to what device i'm referring to:
http://www.aoyue.eu/aoyue-soldering-hotair-rework-desoldering-station-preheater-repairing/aoyue-adjustable-digital-station-lead-free-soldering-iron/aoyue-int2900-digital-lead-free-soldering-station-smd-soldering-iron-wq-serie.html

The real deal is how the tip was built + fit into the heater rod "optimally".

Aoyue, Quick and those Chinese soldering iron manufacturers are basically started their business by cloning Hakko 936.

Until nowadays, I don't see many reviewers review the tip technology involved.

Say using FX-888D (same heater & tip as Hakko 936), using the real tip vs dodgy one is pretty obvious, don't need to scientifically test them, you can instantly feel the difference between genuine tip vs 1 dollar tip.

As above close up photos, the genuine one has a proper copper insert or maybe coating ? While the 2nd dodgy one, the hole is off center and has a tiny crack (if you look carefully), while the 3rd one is basically hopeless, its made from steel with no copper inside what so ever.

good point  :-+ looking around on Youtube i did find FFcossag channel he did a teardown of the Aoyue 2901 handle i really liked.. seems exactly what your saying.. so it seems i'm better of with a Hakko FX-888D or something that is decently constructed as the TS-100 will be waiting because there might me something new on the horizon from the TS-100 camp..
 

Offline TuxKey

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #27 on: March 20, 2018, 12:05:46 am »
i just received a reply from the people at WilTec they do the distribution in europe for the Aoyue brand or so it seems..

So yesterday i contacted them with this email;

Dear Aoyue,

I'm contacting you because i'm interested in your products but unsure of the quality control and find the number of good in depth reviews of your hardware lacking. I live in The Netherlands and i'm looking to buy a new soldering and desoldering sollution. i'm looking to buy Hakko or Aoyue pretty much all other brands are out.

Last couple of weeks soldering irons have bin a hot topic on EEVblog youtube channel and EEVblog forums.
The question raised is "New vs old technology". The newer being the soldering tips that house the heating element all in one tips vs the older ones that have a separate heating element and tip.
Dave from EEVblog does good job covering this simple yet complex subject of which one is better. in most cases like everything in life it depends on the use case but still there are clear advantages to the models that have the heating element and tips all in one. The Hakko FX-951 costs around €280 vs the Hakko FX-888D €98. while you sell the Leadfree soldering station int2900 digital for €63 ....

In all the comparisons Dave does on EEVblog he is comparing the Hakko FX-888D & JBC CD-2B & Weller WE1010.
But in my opinion there is a good option missing in this comparison and that's the "Aoyue 2900".

Therefore my question is why don't you send him a station to do an in depth review???
i don't know if he is willing to do the review and if youre able to send him a station at all but in my humble opinion Aoyue needs a bit more coverage and mentions in discussions about which soldering irons to buy...

videos mentioned:

EEVblog #1063 - Weller WE1010 vs Hakko FX888D Soldering Station
#https://youtu.be/tlKg6rSMPEs

EEVblog #1064 - Soldering Irons OLD vs NEW
#https://youtu.be/scvS2yeUH00

EEVblog #1065 - Soldering Iron Power Delivery Explained
#https://youtu.be/yyt0X2CGDRM

With regards


Their response was;

Dear Customer,

Thank you for your friendly e-mail.

I´m really sorry but we can´t sent test-station to everybody who want to test it and make a review of it.

Have a nice day.

Für Rückfragen stehe ich Ihnen gerne zur Verfügung.
If you require any further information, feel free to contact me.

Mit freundlichen Grüßen aus Eschweiler
Best regards from Germany

Nicole Lingens


Ahh well  :palm:
It's all ok everyone is free to do what's best for them.. i will have to base my next purchase with the info i have and can find.
So for now it's looking like Aoyue is loosing from what i'm reading.. 
 

Offline SilverSolder

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #28 on: March 20, 2018, 12:57:05 am »
For hobby use, I like the primitive analog control loop solder stations, with just a temperature control knob (i.e. Hakko 936 et al).

- Cheap.  You can have 2 of them on the go with different tip sizes, overall faster and better than one single "good" unit with tip changes

- Super fast to change temperature up and down with the knob (use as manual setback temperature control for tip life)

- For really serious thermal sinking projects, a Weller 140/100W soldering gun will destroy any soldering station (and the board too, if not careful!)
 

Online hli

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #29 on: March 20, 2018, 01:24:55 am »
It's not a fixed amount, but the amount is dependet of the thermal current.
Thinking of thermal current (applied heat) instead of temperature explains this much better. Thanks!
 

Offline timelessbeing

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #30 on: March 20, 2018, 06:06:39 am »
With a purely "resistive" model, the tip would always be colder than the temperature at the point of measurement, by a fixed (or maybe proportional) amount. I understand that. This can be handled by defining an offset temperature. But it does not explain the delay in regulation, and why the Hakko does not go into full-power mode when the temperature drops too low (which it should when soldering on a big ground plane).

That's what I was thinking. There has to be a way to model the relationship between sensor and tip temperature in firmware.
 

Offline Brumby

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #31 on: March 20, 2018, 12:56:34 pm »
That's what I was thinking. There has to be a way to model the relationship between sensor and tip temperature in firmware.

That could be fun.

The big unknown is the rate of heat loss from the tip to the joint.  Are you soldering a single pin to a thin track or a spade connector to a massive ground plane?  You would need to integrate the power over time and correlate sensed temperature against the physical arrangement of the system.
 

Offline MT

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #32 on: March 21, 2018, 03:16:07 am »
In the video he made an heat transfer analogy:
Just as water will only boil at 100degC regardless of amount of heating power.

It's guaranteed that making a god soddering joint at -20degC will require a lot more heating power.

Charles Darwin's The Voyage of the Beagle:

"Having crossed the Peuquenes (Piuquenes), we descended into a mountainous country, intermediate between the two main ranges, and then took up our quarters for the night. We were now in the republic of Mendoza. The elevation was probably not under 11,000 feet [...]. At the place where we slept water necessarily boiled, from the diminished pressure of the atmosphere, at a lower temperature than it does in a less lofty country; the case being the converse of that of a Papin's digester. Hence the potatoes, after remaining for some hours in the boiling water, were nearly as hard as ever. The pot was left on the fire all night, and next morning it was boiled again, but yet the potatoes were not cooked."
 

Offline KL27x

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #33 on: March 28, 2018, 06:07:23 am »
This explains why RF is always going to demolish nichrome heating in the really skinny pointy tips. No temperature gradient has to be suffered between the tip and the heater.

You could put a temp sensor on the joint/heatsink. Then up the set temp on the Hakko until the sensor readings on the joint match with the JBC. This would illustrate how much more temperature drop/gradient the hakko has under this particular load, with this particular tip. And it would serve to show how much hotter you would have to run the Hakko in order to get a similar performance for this particular type of simulated task. It seems like this is the part that is missing to link the theoretical difference to practical. We know one is better in this regard. But we don't have any indication of how much. Does the hakko catch up at 275 or 350? I am curious if JBC users actually routinely solder boards at set temp of 270C. That would be pretty impressive.  Most of my soldering is done at a verified 315C with my 888, FWIW, (leaded, of course, and 2 sided boards).

The theoretical benefit of being able to run the JBC at a lower temp (how much lower, we don't really know from this demonstration) and thusly increasing tip life is, of course, theoretical. I'll add another theoretical benefit of less frequent tip cleaning, due to less flux burning/boiling at this lower set/no-load temp) But in practice, it could very well go the other way around, due to various other factors in the tip construction and material selection and manufacturing processes, or even available tip styles. The hakko tip might end up lasting longer (and perhaps even require less frequent cleaning) even if you have to run it X degrees higher for what you need the stations to do for you. And of course, in practice, the cost of the tips is going to be a factor in which one ultimately performs "better," once we pass a certain threshold of "they last long enough."

It is interesting to know the how and why and the real, actual improvement that JBC has attained. I don't question that it is better in this thermal drop/gradient. But I wonder how much gain this is? This could be a giant, practical improvement. Or, for all we know, it is simply scraping the bottom of the barrel for that last little bit of efficiency that is left on the table which amounts to little more than bragging rights. If the latter is the case, it wouldn't stop the marketing team, nor consumer imagination, from turning a mountain out of a molehill.

The most important thing is how it works in practice for what you use it for. Costs, availability, ergos, and all that other stuff inevitably comes into play, as well. Basing your decision on one undeniable - but not as of yet quantified in any meaningful way - improvement is not necessarily smart.

Another interesting question - to me, anyway - is how much, if any at all, of the improvement we see is due to smart algorithm. Theoretically, it would be possible for the station to have preset data tables for a given tip and given temperatures, or even better some kind of pure algorithm if possible, that would allow it to calculate and correct for the expected temperature drop given the past history of sensor readings and power output down the the last fraction of a millisecond. If this is in effect, I wonder if it ever goes wrong.  The usual PID problem is of having a fixed thermal mass and correcting for overshoot. This is a bit of a different pickle.
« Last Edit: March 28, 2018, 07:03:31 am by KL27x »
 

Offline thm_w

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #34 on: March 28, 2018, 07:54:53 am »
This explains why RF is always going to demolish nichrome heating in the really skinny pointy tips. No temperature gradient has to be suffered between the tip and the heater.

Some views of the two internally:
http://www.eevblog.com/forum/reviews/metcal-sttc-soldering-cartridgetip-teardown/
http://dangerousprototypes.com/forum/viewtopic.php?f=56&t=2457&start=675

I like your idea for a temperature test.
 

Offline timelessbeing

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #35 on: March 28, 2018, 05:10:20 pm »
I doubt that the heating is even throughout the tip. Plus when you're soldering, heat is escaping out one end. There will definitely be gradients.
 

Offline KL27x

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Re: EEVblog #1065 - Soldering Iron Power Delivery Explained
« Reply #36 on: March 31, 2018, 12:13:12 pm »
Quote
I like your idea for a temperature test.
I don't have a JBC. But I did this test on an 888 and a T12 Bakon.
http://www.eevblog.com/forum/reviews/t12-clone-vs-888-practical-test-results/
 
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