Soldering iron tip heat transfer

[mubes]

Hi there,

My soldering iron always seems to take forever to heat up and keep hot.  The tip is very loose on the ceramic element...so heat transfer isn't so good.

Having a bit of a brainwave I smeared some heatsink compound on the ceramic, and the performance is _hugely_ improved.

Question: Downsides (the compound seems stable so far)?

DAVE

[flolic]

Downsides? You will find out when you try to change the tip 

[BravoV]

Question: Downsides (the compound seems stable so far)?

Downsides ? My guess of the possibilities :

1. The overly cooked paste will solidify and turned into hard material bonding the tip to the heater, so next tip change = the whole tip+heater and worst whole iron replacement. 
2. Over temp'd paste material turned into corrosive goo that eats your tip from the inside and made it larger, so more goop on next round  , and hopefully doesn't affect the heater. 
3. Extremely and prolonged over cooked filler material in the paste (not the ceramic) will turned into toxic fume ?   

[mubes]

I considered these possibilities (and to be honest, the iron/element is sacrificial to try this out) but there are plenty of thermal greases around that operate to at least 360 centigrade with retained thermal and mechanical properties...that's not the same stuff I used for the experiment but its worked so well that I'm going to see if I can find some more appropriate grease for the job (e.g. Red Ice 611)...is there anything else to be aware of, and does anyone else have any experience of this or can recommend specific compounds?

DAVE

[Psi]

some tips have a metal cylinder fitted into the hole as a kind of spacer.
I've had a few tips where this eventually fell out.
If your tip is like this and missing this part it would explain the problem.

[amyk]

Here's one good for up to 450C: http://www.mueller-ahlhorn.com/fileadmin/Downloads/PDF/PDFDateien/TG_20041_en.pdf

There are graphite and copper-based compounds which can endure even higher temperatures. Just make sure it's not thermal cement!

[dr_p]

Can't you fill the gap with a piece of aluminium foil from a soda can?

[vsq]

Maybe the cheapest option would be to use copper paste. It is commonly used as a lubricant for automotive things in high temperature environments like exhaust manifolds. I would suppose it to have good heat transfer characteristic, being copper.

[mubes]

I'm pretty sure this is business-as-usual for this particular iron, but the improvement in performance is so significant that it's worth chasing it and doing it properly.  If I do use a high temperature, thermally conductive, grease then it should make the tips come off easier, not harder.

Can't really see a downside to this, and I'm wondering why no enterprising company isn't selling high temp thermally conductive grease for exactly this sort of application....so I'm guessing I'm missing something???

DAVE

[SeanB]

Probably there is a market repackaging Copaslip in syringes, but then again a tube of it is pretty cheap at the local auto parts counter. Survives being used on brake assemblies as a lube and stays lubricating even after being coated in brake dust and rust from the linings. I have used it on CPU heatsinks as a thermal paste as well, it works well.

[mubes]

Hmm,

I think you might have something there SeanB ... it's good to 1100 degC. Will have a scratch around in the garage in the morning.

DAVE

[Marlosol]

HI!
  Given the warning about the thread's age, I'll start by saying this is solely to add information for others coming across this thread -- not advice for the original poster, who has solved his problem, by choosing to use an automotive product.

There was a question about the kind of heat-sink compound to use.  After looking at its temperature stability (up to 340ºC) I'm going ahead with a very small amount of (the widely available and commonly used) ZP-340, just because I have it on hand.

Also, I'm using it in a thermostatically-controlled iron and don't expect to set it above 300.  The fellow in the link, who repaired his same-model iron, says the higher temperatures just aren't needed. 

From what I can determine, when exceeding the upper thermal limit, the compound may begin to 'run' -- but in this location, applied only to one side of the tip's rod section, it couldn't be a problem, because I used so little. 

Thanks to the original posters and this forum for very useful information.  I was beginning to suspect my iron had a heat-transfer problem, as may  be read in the linked thread.   

Extensive searching of the Internet brought up this post, and only this post, for a confirmation this problem exists, and then giving its solution.  Thanks for this forum and the quality of its information. 

Given the 'necropost' warning, two years of age didn't reduce the post's value, one bit. I hope the moderators approve.

[zega]

Idea is good, compound is good except note this (for copaslip)

Grease Base: Bentone
Consistency: NLGI #1
Base Oil Flash Point: 253 degrees F

This low flash point kinda worries me but still will pursue that bit further.

BTW this is solved in all of soldering irons with "composite tip" that kind has tip in which is embedded heater, heat transfer is great in such a case, and you can buy these soldering irons starting with Ayoue 2930 (measured solder melting temperature from power swithch flip is 10 sec (will put on YT) that model is inspired with  hakko 9xx series, there also uses composite tip tech. newer series is named FX100, then goes Metcal, JCB, Weller (worked with all of them but JCB and Hakko)...
Metcal 5200 (dual) which i use is definately finer tool but what frustrates me is "boot time" boots like a windows so time to melt solder is comparable with Ayoue after flipping the switch (will have to make a video on that one also)...
Since Ayoue 2930 starts with 72$ US delivered, i suggest you start there if you want decent performance and reasonable tip quality...

[daybyter]

You have seen this russian video, in which the guy puts some graphite into the tip of his hakko clone?

[timofonic]

You have seen this russian video, in which the guy puts some graphite into the tip of his hakko clone?

Can you put the URL? please

[AF6LJ]

Probably there is a market repackaging Copaslip in syringes, but then again a tube of it is pretty cheap at the local auto parts counter. Survives being used on brake assemblies as a lube and stays lubricating even after being coated in brake dust and rust from the linings. I have used it on CPU heatsinks as a thermal paste as well, it works well.

I hope that stuff isn't conductive.
I have one of those cheap A$$ irons for emergency use only and those things are in my opnion dangerous to start with.



The best answer.....
can be found by googling..
Weller or Hakko.

[GreyWoolfe]

I really hate to belabor the point, but this thread is an example of why people should save up additional coin of the realm and purchase a decent quality soldering iron (Weller/Hakko) and buy OEM tips.

[AF6LJ]

I really hate to belabor the point, but this thread is an example of why people should save up additional coin of the realm and purchase a decent quality soldering iron (Weller/Hakko) and buy OEM tips.

Indeed;
Starting out good tools go a long way toward making for good work.
Not meaning to demean the OP but you really do have to start out with reasonably good tools.
You can't fix a car with a pair of pliers and a straight slot screw driver.

A good soldering iron is a Must-Have.

[daybyter]

https://www.eevblog.com/forum/reviews/hakko-936-clone-soldering-station-improving-performance/msg780881/#msg780881