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Best Temperature soldering without peel off solder pad

momolou

momolou

Active Member
what best temperature soldering for solder vintage old amplifier like Sansui D11, Technics V8080, Sansui Au 517, Sansui Au 719 etc

i am using 40 watt solder , but sometime solder pad just peel off,

after that i am buy temperature controlled solder station exactly like this one solderng station.jpg

what best temperature for enough hot but not peel off solder pad from pcb
 
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I would say between 300 and 350°C.
If you are doing frequent restorations, it’s best to invest in a Hakko desoldering gun.
 
I do mine closer to 650.

Higher heat, less time on the joint.

Less likely to melt stuff you don't want getting hot, less likely to have a "cold joint".
 
I use a 20 year old "Pace" soldering station. Built like a brick sh#thouse and still going strong. It's mainly set to 350 Deg C for soldering and that depends on the application. If your pads are coming off the boards it's either your temp is set too high or your technique removing components is incorrect.
 
Depends on who you talk to and how long they have been doing it. Starting out somewhere in the 350-450 range but once you get better at it I know people doing 600+. Personally I don't go that high my hand isn't steady enough for me to not touch things accidentally.
 
Still learning this. What I learned up to now:
1. Clean, clean, clean. Oxidation is the invisible enemy from heat transfer!
So clean solderpad + component lead and put some flux on to prevent immediate oxidation. Clean tip of solderiron add some solder and clean this of just before desoldering.

2. Solder/desolder preferably one connection at a time, may be two but not more. Clean and add solder to tip and clean again. This takes time, requires patience but in the end works faster.
3. When solder on connection is not melting add fresh solder to iron tip and melt solder first to break the oxidation.
4. When it takes more then 2-3 seconds back of the joint and let it cool down before going back in.
5. Use appropriate tip for joint you want to solder / desolder, the more contact surface the less heat ( high temperature ) and time needed. I like chisel shape in different widths because often you can not lay down the tip to get more surface contact.
This depends also on amount of steel/copper you have to heat
Depending on the situation above I use between 320-370 °C
 
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It's usually the combination of heat and too much pressure particularly that will lift solder pads. Also incomplete removal of solder securing a component lead to a pad is another cause. As in @GrisPato 's post above patience and allowing the joint to cool down before continuing can help a lot.

I use a pump style mechanical solder sucker and solder braid. Desoldering workstations can work well especially if you have a lot of joints to do. I have used a Pace workstation but prefer the above tools overall.

As for temperature 370°C (4PTCC7-1) for standard stuff, and 480°C (PTDD-9) for heavy duty stuff. Which corresponds to Weller No 7 bit 3.2mm, and Weller No 9 bit 5mm. (700°F & 900°F)
 
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I go full 850 on my Weller WX1010. IMHO the key is to get in and out quickly, Dwell time is what causes damaged traces based on my experience. I only use Kester "44" 60/40.
 
I end up adding new solder a lot, just to suction out a joint for component removal. This is also a problem on newer equipment where the pin density and "squeeze the nickel until the buffalo shits" wave soldering process leave so little solder on the pads my delsoldering rig almost can't make enough contact to melt what is there. This is further complicated by the thru-hole plating on many newer boards where non-SMT components are used.

The factory solder Sansui used for production from late 1960's to at least the late 70's is an odd alloy. It has that dull, pasty quality about It. Probably high lead content, but I'm not entirely sure what the makeup is. It also tends to crack (cold/dry joints) more easily than modern good quality lead/tin solder. It has an odd odor, too. Where I actually kind of like the smell of the normal Kester rosin core solder I use (in the same way one might like the smell of diesel or gasoline) the Sansui factory solder gives off an odor that is not particularly pleasing.

I generally maintain temp of 350-400°F on my soldering rig, but will go higher if doing point to point wiring, wire to chassis ground straps (think driver boards on a 5000/A/X) or working on a wide, thick PCB trace such as used for a grounding buss. Some big snap fit caps need more juice as well, given the terminals and pads act as a heat sink.
 
ok folks. Some doing it right, mentioning F or C. Others missing that info.

Really need it what with some irons only showing one of those temps and folks from different countries speaking in Local temps, C or F.

700F (my Weller dial is in F) works for me for most. More for a large pad.
 
Due to the fact that nearly all of these boards are single sided, care must also be exercised to not apply ANY pressure via the component lead(s) to the pad on the solder side.
With a two sided board, you have a pad on both sides of the board, and a cylinder of copper connecting them. This acts like a rivet, and helps keep the pads adhered to the board. These single sided boards lack the “rivet” structure, so any stress on the lead from the component side will be transmitted to the pad, and the connected trace. Add heat, and you have the recipe for losing pads/traces.
In fact, on prototype boards that need “correcting”, I have cut through both ends of an offending trace with an Xacto knife, and applied a hot soldering iron tip to the piece of trace that I want to remove. More often than not, the piece of trace will come right off, stuck to the tip of the soldering iron by surface tension.
 
Blue Shadow said:
ok folks. Some doing it right, mentioning F or C. Others missing that info.

Really need it what with some irons only showing one of those temps and folks from different countries speaking in Local temps, C or F.

700F (my Weller dial is in F) works for me for most. More for a large pad.
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The Hakko FX-888D's I've bought came set to 750°F. I left them there, and never had an issue.
 
I think I should chime in here, since I've been in the aerospace hardware business in many different facets for over 26 years. Am certified to the NASA standard.
Professionally, for my crew I have bought (on the company tab!) Metal towers, which I'll go out on a limb and say probably the most expensive set up one could find. You never see what temperature you're soldering at since mecal instantly adjusts to the correct temperature required. Now, not everyone needs to spend well over a grand to solder. At home, where I tinker around on various projects (beloved Sansui) my work bench has had anywhere from the radio shack to hakko,american beauty,velleman,wep, weller etc,etc. My current home set up is a dual iron Weller, and it's here to stay. It's never let me down on any soldering required situation. There are certainly a lot of good irons out there, I've tried a majority of them, but I have to recommend weller-IMHO.
To get to momolou's question; regarding temperature, My general all round temp is 700 F. On larger lands/ground planes 750 F.
Some very good answers have already been mentioned.Contact time is critical, the higher the temp the shorter the contact. Removing most of the existing solder in the area & replacing w/ new (leaded) is certainly a very effective way when solder isn't flowing-especially on vintage pcb's.
You should never be putting any physical pressure on the eyelet being worked. the iron should just make contact to do it's thing. And remember, FLUX is your friend!
I've gone on too long. I hope these tips help you. I could go on with this subject for paragraphs-great for insomniacs....
 
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