Is that a big relay? Looks like a standard size to me.
I have used a solder sucker to take a lot of the solder away and then remove the rest with braid. If you do not have braid, then the outer screen of co-ax cable can be used. The thinner the wire the better so that capilarity attraction is high. The braid/cable must be clean and a bit of flux can be a help.
If there is a little bit of clearance, the pins can be moved to the centre of the hole so the solder does not grab again.
I now have a heated solder sucker, this is like a soldering iron but with a hollow bit. Put it over the pin, wait for the solder to melt and then push the button. It clears the solder down the hole quite well but you may have to centre the pin.
For integrated circuits I have made a wide bit for my iron using a piece of copper central heating pipe, squashed in a vice so that it jams on the end of my iron. I can do eight at a blow!
Some people use hot air blowers but I have never tried this.
I have used a solder sucker to take a lot of the solder away and then remove the rest with braid. If you do not have braid, then the outer screen of co-ax cable can be used. The thinner the wire the better so that capilarity attraction is high. The braid/cable must be clean and a bit of flux can be a help.
If there is a little bit of clearance, the pins can be moved to the centre of the hole so the solder does not grab again.
I now have a heated solder sucker, this is like a soldering iron but with a hollow bit. Put it over the pin, wait for the solder to melt and then push the button. It clears the solder down the hole quite well but you may have to centre the pin.
For integrated circuits I have made a wide bit for my iron using a piece of copper central heating pipe, squashed in a vice so that it jams on the end of my iron. I can do eight at a blow!
Some people use hot air blowers but I have never tried this.
Thank duke37. lol. In relation to the smd's next to it it looked big to me. I tried solder sucker and braid but it was mounted flush on the board so could only work from the one side. That heated solder sucker sounds like the business. I'll try the copper pipe, with not squeezing the end totally flat it could sit over the pins, might work.
- Joined
- Jun 21, 2012
- Messages
- 4,968
As a last resort, you could cut the relay off at its base using a fine-toothed coping saw. That will expose the terminals for removal one at a time. Make sure you really need to replace the relay, and have a replacement on hand, before sacrificing the original relay.
If you use the method of a wide soldering bit heating all contacts together, then do not suck the solder away. In fact, it may be better to add a little solder so that all contacts can be melted at the same time.
What is wrong with the relay? It may be possible to change the contacts 'in situ'.
What is wrong with the relay? It may be possible to change the contacts 'in situ'.
Thanks for that tip, I'll try it with a cut off pin that I'm trying to remove from a pcb.
This relay was trying to drive a solidly seized electric motor so a greyish deposit formed on the plastic housing in the region of the contacts. So I removed it and cleaned the contacts and it seems to work. But still checking the board for further damage as it had burned a trace on the board between one of the relay solenoid's leg and a diode.
This relay was trying to drive a solidly seized electric motor so a greyish deposit formed on the plastic housing in the region of the contacts. So I removed it and cleaned the contacts and it seems to work. But still checking the board for further damage as it had burned a trace on the board between one of the relay solenoid's leg and a diode.
I hope so. I just get the feeling that PCB solder these days is a lot tougher than 20 years ago. Now I sometimes have to turn my soldering station up to 450 (the highest that it can go), where damage to the pcb is just about a certainty, and I still battle to flow the solder. What's next - blowtorch?
HellasTechn
- Apr 14, 2013
- 1,579
- Joined
- Apr 14, 2013
- Messages
- 1,579
True because they use this silly lead free solder !!!!
How about useing a desoldering station with vaccum pump ?
I have this one and i just love it !!!
http://www.ebay.com/itm/DISSALDATOR...908005?hash=item3cfa272865:g:SVEAAOSwofxUi0Gh
How about useing a desoldering station with vaccum pump ?
I have this one and i just love it !!!
http://www.ebay.com/itm/DISSALDATOR...908005?hash=item3cfa272865:g:SVEAAOSwofxUi0Gh
Last edited:
HellasTechn
- Apr 14, 2013
- 1,579
- Joined
- Apr 14, 2013
- Messages
- 1,579
It is possible that your solder tip and/or the heating element are worn out or maybe you dont use a suitable solder tip to transfer enough heat to the solid solder?
Yeah, that would come under 'miniature' for the ones I use.
It looks like a Finder 40 series they rate it as 'The Finder 40 series are miniature PCB or plug-in relays'
If it is switching an inductive load, it may not reach the 8Amp contact rating.
M.
It's very important to add a decent quantity of solder to the iron's tip first to aid heat transfer and get the soldered joint quickly melted. If you bring the iron in with no or very little solder, it will drastically cut the amount of heat going into the joint and lengthen the time it takes to melt the old solder. I run my iron at 320°C for most leaded soldering and leaded/lead-free desoldering work and I'd easily have that joint flowing in about a second.
I posted a soldering gun technique a while back but I don't know which section of the forum it's in. It included photos.
Anyway a soldering gun will produce a lot of heat fast and you can bend up a box like loop from 12 or 10 gauge solid copper wire. It will heat all pins simultaneously. The relay will just fall off the board via gravity. And yes, I always add more solder to each pin prior to using this method.
Chris
Anyway a soldering gun will produce a lot of heat fast and you can bend up a box like loop from 12 or 10 gauge solid copper wire. It will heat all pins simultaneously. The relay will just fall off the board via gravity. And yes, I always add more solder to each pin prior to using this method.
Chris
Thanks for all the tips guys, much appreciated. My soldering/desoldering skills have already improved dramatically. But lol, I had always regarded those soldering guns as toys, just shows how wrong you can be be. Now to find one in South Africa, sigh!
Definitely not a toy. While they would be my choice of last resort for typical soldering jobs they lend themselves well for de-soldering jobs like this and when you need a lot of heat fast when soldering to heat sinking planes. Back when plated steel chassis were the norm a typical pencil iron was useless when soldering to it or a grounded terminal lug. Give me a Gun. Better yet make it a Magnum! It also makes a more practical field service tool. Years ago I had a Marine Electronics - Land Mobile Radio shop. My irons remained on my bench while my gun traveled with me to the field or dock. I wasn't going to be cracking open radios in the field anyway.
Chris
