Solder flux question

silverdale

VIP Member
VIP Member
Joined
Aug 2, 2007
Messages
5,413
Reaction score
7,025
I've always used a very thin liquid type flux for small electrical soldering work but its not much good for rework jobs.
Which brand of gel flux would you use for small rework jobs ?.

I've been looking around reading and watching but there's a 1000 n 1 types and brands. Lots seem to use the syringe gel type flux to keep the surface tension when heating. Any brands or links would be good. Any tips or tricks of the trade would be nice as well.
 
I rework stuff both at home and at work (although I try to dodge being type-cast at work...) and I have the same issue.

That type of flux is good for removing shorts on 0.5mm pitch TSOP etc but I have tried it for BGA replacement and it wasn't so good.

Have a look at Louis Rossmann videos, he lists the stuff (in the video comments) he uses and knows what he's talking about :).

I'd like to try some of that gel type.
 
Last edited:
I use AMTECH Flux Type RMA-223 works well for me
 
Just checked mine and it passed it's expiry date on the 21st of October. Always kept in the fridge so should be ok.

Amtech NC-559-V2-TF not cheap though. Beware of knock-offs.
 
I rework stuff both at home and at work (although I try to dodge being type-cast at work...) and I have the same issue.

That type of flux is good for removing shorts on 0.5mm pitch TSOP etc but I have tried it for BGA replacement and it wasn't so good.

Have a look at Louis Rossmann videos, he lists the stuff (in the video comments) he uses and knows what he's talking about :).

I'd like to try some of that gel type.
Louis is very entertaining, good at what he does albeit being a shit solderer. He'll admit to that. Both he and Jessa (iPadrehab) produce very informative videos. The only trouble is most viewers think they can also do it. They buy shit equipment and then proceed to murder their macbook or iphone.
I've got one of these to rework shortly. A big cleanup before I can start doing anything though, God knows which flux has been used on this and he managed to "blow off" several components. The area in question is less than a half inch square.

The chip is a 28 pin device and controls the charging of the battery, he tried to replace it. o_O

LB# 820-2879B.jpg
 
Louis is very entertaining, good at what he does albeit being a shit solderer. He'll admit to that. Both he and Jessa (iPadrehab) produce very informative videos. The only trouble is most viewers think they can also do it. They buy shit equipment and then proceed to murder their macbook or iphone.
I've got one of these to rework shortly. A big cleanup before I can start doing anything though, God knows which flux has been used on this and he managed to "blow off" several components. The area in question is less than a half inch square.

The chip is a 28 pin device and controls the charging of the battery, he tried to replace it. o_O

Is that a missing SMD pad to the bottom left of the QFP pads?

Eventually getting them to buy me some better hot air equipment at work :). Still can't justify BGA but it would be nice.
 
Is that a missing SMD pad to the bottom left of the QFP pads?

Eventually getting them to buy me some better hot air equipment at work :). Still can't justify BGA but it would be nice.
Could be a missing pad, will know better once cleaned up. There was a cracking bga rework machine on sale here a while back on my local Gumtree. Was way outside my price range though, around £3000 if I remember right. Was being sold by MIRA as they had bought a better model
 
Could be a missing pad, will know better once cleaned up. There was a cracking bga rework machine on sale here a while back on my local Gumtree. Was way outside my price range though, around £3000 if I remember right. Was being sold by MIRA as they had bought a better model

What make was it?

I priced an Ersa one at work, it was probably one of the best Ersa did but we couldn't justify >£40k :).
 
What make was it?

I priced an Ersa one at work, it was probably one of the best Ersa did but we couldn't justify >£40k :).
Wish I could remember, I had a look in case Gumtree would show past items but apparently not. The £3000 was a snippet of it's true value
 
Wish I could remember, I had a look in case Gumtree would show past items but apparently not. The £3000 was a snippet of it's true value

I've looked into one for myself just out of interest, I couldn't justify one at all though. I'd probably go down the second-user quality route. I did that with my hand-soldering stuff, all Weller. Many years ago I got a MT1500 demonstrator unit from a (former) rep for £50 :).
 
This rings a bell @Spectre. Quite sure this was the model but I seen it on Nuneaton Gumtree and it was probably 6 months ago.

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.
 
This rings a bell @Spectre. Quite sure this was the model but I seen it on Nuneaton Gumtree and it was probably 6 months ago.

Will not have been cheap if Pace :).

I bet they were upgrading because their software people are making them get rid of XP or earlier machines and it uses one for some reason. Even needing a 32-bit parallel dongle messes things up if using 64-bit Win7 or so.
 
Price new was upwards of $30,000 so don't seem such a bad price. Was definitely that model as I remember the youtube videos I watched at the time. I was seriously interested in buying it at the time but knew I couldn't justify the cost.
Would have loved to have a play though ;)
 
Price new was upwards of $30,000 so don't seem such a bad price. Was definitely that model as I remember the youtube videos I watched at the time. I was seriously interested in buying it at the time but knew I couldn't justify the cost.
Would have loved to have a play though ;)

I do well not to see such things or I end up with mad stuff during buying frenzies :). If I had a bit more room I'd probably have been tempted but then have nothing to rework :S.
 
Wish I hadn't mentioned it now Spectre, got me thinking again, lol. What I really need is a better microscope-camera but I'm reaching the end of my working life so really shouldn't be investing in new equipment. Think I'll try and improve the one I'm using, an adapted webcam.
 
Wish I hadn't mentioned it now Spectre, got me thinking again, lol. What I really need is a better microscope-camera but I'm reaching the end of my working life so really shouldn't be investing in new equipment. Think I'll try and improve the one I'm using, an adapted webcam.

Microscope was one of my large purchases, not for rework but for smaller stuff. I got a Mitutoyo FS-60L with near-full suite of "normal light" lenses. I've taken a few ICs apart to look at, and removed tamper mesh from smartcard silicon. I do have the pictures of that and they are good enough that something like DeGate could be used to reverse engineer parts of the card.

I think I'll be needing a soldering microscope at some point though. We talked about that at work and I was thinking of cling-film or something to stop flux splashing onto the lens. Another department has a Vision Systems Mantis but I don't think anyone should solder under that.
 
I usually use my Amscope se400‑z when hand soldering. It's not a trinocular though. I have my camera setup on my hot air rework stand and can either hot rework or hand solder while looking at the pc monitor.
My solder station is Hakko and I have a micro iron which is ideal for 0402.

I've always thought the mantis to be quite ugly. Know a guy who runs a tv engineers forum who had one, he reckoned the working distance wasn't great and he too was worried about flux splashback. I always fancied a Tagarno.
 
I usually use my Amscope se400‑z when hand soldering. It's not a trinocular though. I have my camera setup on my hot air rework stand and can either hot rework or hand solder while looking at the pc monitor.
My solder station is Hakko and I have a micro iron which is ideal for 0402.

I've always thought the mantis to be quite ugly. Know a guy who runs a tv engineers forum who had one, he reckoned the working distance wasn't great and he too was worried about flux splashback. I always fancied a Tagarno.

I've tried the Mantis but it is a bit strange.

I think some of the cheap Amazon ones would do for me. Difficult to got one for work as I'd have to get one bought in through an approved supplier :(. I need to draw people away from me though for their rework needs!
 
I'm looking at buying a small setup, nothing major more hobbyist. I've soldered for years all the usual but nothing nano small but I woulds like to think I have a basic understanding plus I've plenty of old boards to practise on :) . What do you think of the hot tweezers say like this;-

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

I know their expensive but I can only imagine if your doing it day in day out it's a huge time saver. What would you recommend if I were to buy a new iron, microscope, rework station, hot tweezers (if possible) ?. Also there's things like the flux is Amtech 559 the best ?
 
I'm looking at buying a small setup, nothing major more hobbyist. I've soldered for years all the usual but nothing nano small but I woulds like to think I have a basic understanding plus I've plenty of old boards to practise on :) . What do you think of the hot tweezers say like this;-

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

I know their expensive but I can only imagine if your doing it day in day out it's a huge time saver. What would you recommend if I were to buy a new iron, microscope, rework station, hot tweezers (if possible) ?. Also there's things like the flux is Amtech 559 the best ?

We have the Weller tweezers at work, 40W per tip and they struggle a bit on 0603 SMDs which are attached to planes. That was one of my reasons for hot air. Also, with finer tips the heat transfer isn't too good and you need fine tips to get to small toe fillets on modern boards. They do have their place though.

On my phone or I'd type more, I'm exhausted after that paragraph.
 
Back
Top