Best solder for RC builds?

[str]

Was wondering if anyone had a type of solder they think works particularly well in RC builds. I'm going to be building my first quad, and looking at solder, I see a few different options:

• Lead based
• Lead free
• Rosin core (flux)

Beyond that, I see a lot of solder rolls including a ratio like '60/40' for their rosin core. What exactly does this mean, and what ratio would be good for a quad build?

While I'm a beginner at choosing solder, I'm not a beginner at soldering, and would prefer something that would be durable over something that would be easy to solder.

And flux -- I've watched a few videos where people swear by using a flux pen, but personally I have never used one. Are they really necessary?

Links to where I can purchase the solder you recommend would be helpful

 

[kacknor]

All from memory, no google today, so forgive minor inaccuracies.

60/40 = 60% lead, 40% tin alloy. The tin component both smoothes out the melt, and lowers the temperature the lead will melt at. A good solder will liquify around 400 degree or so, lead alone needs about 700. MUCH Less tin will smooth it our, only needs 4 to 7%, but to get that melt temp down you need a lot.

Rosin Core is the flux. Flux cleans the wire, early flux was acid, and it worked great, but tends to eat electrical wires after a time and the industry switched to rosin. The tin of flux in my picture is Rosin Flux. It also cleans metal under heat and lets the solder stick without damage to the metal. Manufacturers for years have added it to the center of a tube of solder for convenience. It works OK, but if you already have a (very) thin layer of rosin already on a bare wire or pad the solder flows and sticks NOW, and not a second or two after the solder melts on it and the stuff from the core cleans the wire enough for it to stick. That's important for electronic components that also have tiny solder joints internally and your goal is to add more without melting them.

I am a believer in old school. Lead based, rosin core. and small tin of flux. I have soldered more in the last year than in the 20 before it. Still using a a can of tin and a roll of solder that, to my horror, followed me home from a former job about 25 year ago. Still have it because soldering pencils usually come with some small bit of solder, and I always used that first. The tin? well a little goes a long way. It's old. How old? there isn't a bar code on the can. Not even half gone.



Nearly as important than the type is the diameter of the stuff you use. This is .40, very thin, melts easy and quick, and works well with a standard 25 watt or a thin 15 what pencil (that I don't have). For the occasional XT60 plug with 12 or 14 gauge wire I also have a 40 watt.

A third hand is a good thing to have, very useful. Also, there is putty that you can pack about those sensitive components to soak up heat before it damages internal parts. Haven't found a need for it for the RC stuff though.

Practice, practice practice. Tin your connections! (flux, and add solder first) Good Solder-Fu is a skill developed over time.

JD

 

[PHugger]

And flux -- I've watched a few videos where people swear by using a flux pen, but personally I have never used one. Are they really necessary?

Lead-free solder is used in plumbing where you don't want lead in your tap water.
For electronics, lead is OK.
Get the thin rosin-core stuff as Kaknor said. It melts faster and is easier to get into tight places.
Flux cleans the base metal (copper) and allows the solder to flow easily and bond to the copper.
It makes it all happen much faster which is especially important when you work on PC boards and components where too much heat for too long can cause damage.
Plumber flux (what Kaknor uses) will work, but I find it to be a bit messy.
A flux pen (felt tip pen with liquid flux) can be much neater and more precise.
They both do the same thing, but I think the paste flux is probably cheaper.
I find I use a lot less of the pen type when applying it to a circuit board - like putting the pin headers on a Naze32.
You can't see the liquid flux from the pen when you apply it, but it seems to just work like magic.

The thing that helped me progress with my solder-fu was a good temperature controlled solder station.
There are a lot of them available at different prices. I use this one -



It's very simple (no temp control) and has worked great for me for years.



Best regards,
PCH

 

[kacknor]

I've seen the flux pens. Look very nice. Yes the tin of flux I have is a bit messy, but dipping the end of the wire is quick, a control rod used as a spatula tins flat surfaces and no pen can replace the convenience of dipping the scaled up solder tip into the flux and pulling out a fresh shiny surface in about half a second.

Besides, I'm a use it up guy. What I have left it likely a lifetime supply.

JD

 

[PHugger]

Tinning and cleaning your iron is an art in itself.
Most stations (including the one pictured) have a small sponge (damp) that you can use to wipe off any scale or buildup on the tip.
They also sell brass "brillo" pads that can be used to clean as well.
It's very important to NEVER sand or file the tip as this will remove the iron coating and ruin it.
The brass in the pads is softer than the iron and won't damage it.
Keeping your tip properly tinned will prolong it's life and prevent oxidation and corrosion.
Having the iron temperature controlled also helps with tip wear.


Best regards,
PCH

 

[str]

All from memory, no google today, so forgive minor inaccuracies.

60/40 = 60% lead, 40% tin alloy. The tin component both smoothes out the melt, and lowers the temperature the lead will melt at. A good solder will liquify around 400 degree or so, lead alone needs about 700. MUCH Less tin will smooth it our, only needs 4 to 7%, but to get that melt temp down you need a lot.

Rosin Core is the flux. Flux cleans the wire, early flux was acid, and it worked great, but tends to eat electrical wires after a time and the industry switched to rosin. The tin of flux in my picture is Rosin Flux. It also cleans metal under heat and lets the solder stick without damage to the metal. Manufacturers for years have added it to the center of a tube of solder for convenience. It works OK, but if you already have a (very) thin layer of rosin already on a bare wire or pad the solder flows and sticks NOW, and not a second or two after the solder melts on it and the stuff from the core cleans the wire enough for it to stick. That's important for electronic components that also have tiny solder joints internally and your goal is to add more without melting them.

I am a believer in old school. Lead based, rosin core. and small tin of flux. I have soldered more in the last year than in the 20 before it. Still using a a can of tin and a roll of solder that, to my horror, followed me home from a former job about 25 year ago. Still have it because soldering pencils usually come with some small bit of solder, and I always used that first. The tin? well a little goes a long way. It's old. How old? there isn't a bar code on the can. Not even half gone.

View attachment 61767

Nearly as important than the type is the diameter of the stuff you use. This is .40, very thin, melts easy and quick, and works well with a standard 25 watt or a thin 15 what pencil (that I don't have). For the occasional XT60 plug with 12 or 14 gauge wire I also have a 40 watt.

A third hand is a good thing to have, very useful. Also, there is putty that you can pack about those sensitive components to soak up heat before it damages internal parts. Haven't found a need for it for the RC stuff though.

Practice, practice practice. Tin your connections! (flux, and add solder first) Good Solder-Fu is a skill developed over time.

JD

Thanks for all the info!

Couple of questions:

• What do you mean when you say 25 watt/15 watt pencil?
• Any idea where I buy some of this heat resistant putty? This could be useful when heating shrink wrap tubing -- I've found that I can easily melt JST connectors with my hot air gun
• Is .40 too thin?

Lead-free solder is used in plumbing where you don't want lead in your tap water.
For electronics, lead is OK.
Get the thin rosin-core stuff as Kaknor said. It melts faster and is easier to get into tight places.
Flux cleans the base metal (copper) and allows the solder to flow easily and bond to the copper.
It makes it all happen much faster which is especially important when you work on PC boards and components where too much heat for too long can cause damage.
Plumber flux (what Kaknor uses) will work, but I find it to be a bit messy.
A flux pen (felt tip pen with liquid flux) can be much neater and more precise.
They both do the same thing, but I think the paste flux is probably cheaper.
I find I use a lot less of the pen type when applying it to a circuit board - like putting the pin headers on a Naze32.
You can't see the liquid flux from the pen when you apply it, but it seems to just work like magic.

The thing that helped me progress with my solder-fu was a good temperature controlled solder station.
There are a lot of them available at different prices. I use this one -

View attachment 61768

It's very simple (no temp control) and has worked great for me for years.



Best regards,
PCH

I'm not a big fan of flux and the residue it leaves. Not only does it look nasty, it can make troubleshooting a faulty circuit harder (at least for me, the flux gunk looks a lot like a leaky capacitor). Would one of the liquid flux pens leave as much residue?

 

[kacknor]

Thanks for all the info!

Couple of questions:

• What do you mean when you say 25 watt/15 watt pencil?
• Any idea where I buy some of this heat resistant putty? This could be useful when heating shrink wrap tubing -- I've found that I can easily melt JST connectors with my hot air gun
• Is .40 too thin?

I'm not a big fan of flux and the residue it leaves. Not only does it look nasty, it can make troubleshooting a faulty circuit harder (at least for me, the flux gunk looks a lot like a leaky capacitor). Would one of the liquid flux pens leave as much residue?

15/25 watt? - The wattage and heat transfer capability of the soldering pencil (iron). Sorry, I use pencil, iron, and gun pretty much interchangeably. A Gun is usually the heavy duty electrical work pistol grip things with the momentary on switch. An Iron is the old plummer tool that in the past, was heated with a blow torch and really DID look like a scaled down iron. A pencil is what we all mostly use, plug it in, it gets hot, is thin and comes in various wattage and the better ones are variable with a base station and integrated stands and cleaning options.

Not sure about the putty. Google it. Unless you are soldering right up against it, normally speed and lowest heat work fine, or if room, put a clip, tweezers or needle nose between your work joint and the object to be protected. That will heat sink away enough to be OK.

If flux is getting on the boards then you are using too much. Try that pen and liquid PHugger talks about. It's obvious he knows a lot about this. I don't see .40 as that thin. .20 is thin, and available.

Take care with that heat gun. Use Rule #4: Know your target and what is beyond it.

JD

 

[dgrigor02]

I was using the lead free stuff from the big-box hardware stores. Not knowing any better I thought I just sucked at soldering.

I ordered some of the 60/40 from amazon here: http://www.amazon.com/gp/product/B00DHHAZ3A?psc=1&redirect=true&ref_=oh_aui_detailpage_o08_s00

The solder alone turned me to a semi-pro. I had no clue the solder you used made such a difference.

 

[rcspaceflight]

Hot air gun for you heat shrinks? I just use a lighter. Quick blasts from a lighter works perfectly fine if you don't mind possible scorch marks on it. But if you're using black heat shrinks, it's not noticeable.

I use the thin rosin core solder. As others have said (but I didn't read everything) the thin stuff melts quicker and it's easier to keep adding solder than waiting for the thicker stuff to melt.

I'm not the best solderer in the world, my technique is lazy, but I've had great success with the thin rosin core solder. I usually melt solder into the connector and then quickly shove the wire into it. It takes a while to get used to how much solder to use, but other than that I've had success with my laziness. Although sometimes it seems to work better if you get solder on the wire first, then you're bonding solder to solder instead of bare wire to solder when the solder is cooling as you're trying to get them together.

 

[kacknor]

Hot air gun for you heat shrinks? I just use a lighter.
...
Although sometimes it seems to work better if you get solder on the wire first, then you're bonding solder to solder instead of bare wire to solder when the solder is cooling as you're trying to get them together.

The heat gun is a lot cleaner and easier on fingers if you have the space to use it. I do use a butane lighter also, for control rods built on the plane. Besides, when salvaging parts from past builds and formerly good ideas the heat gun is great to melt old hot glue to scape it off.

Putting the solder on first is the Number One best way to succeed. It's called "Tinning" as in 'Tin the wire first'.

JD

 

[PHugger]

Heat Shrinking.....

I used to use a hair dryer style paint stripper, but it was way overkill and potentially dangerous (too hot).
I was in a Radio Shack store that was clearing out all of it's inventory and found this for 50% off -



I just noticed that Amazon is selling them as well.
http://www.amazon.com/RadioShack®-300W-Heat-Gun-Reflector/dp/B00M1AOCWY

Not as powerful as the paint stripper, but I've seen some claim that they can be used for re-flow work.

It has an attachment that is perfect for heat shrink - very precise.
I believe these are also popular it scrapbookers (they call it an embossing tool).



Best regards,
PCH

 

[SP0NZ]

First of all, I absolutely suck at soldering. I've always used cheap pencil-style irons 25-40 watts and crap solder. My brother is in the same boat with regards to soldering. Last year at Flite Fest CraftyDan brought his soldering station and let people use it. My brother was one of the people that did. He said it was absolutely amazing how much of a difference a good station and good solder made. After two years of struggling using crap tools and materials, I finally decided to put an end to the frustration. I asked CraftyDan for his recommendations. My soldering station order arrived 2 weeks ago. Here is what I got:

Soldering Station:
http://www.amazon.com/gp/product/B00RLDAWZM?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00

Tips:
http://www.amazon.com/gp/product/B00KYVV9DM?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Solder:
http://www.amazon.com/gp/product/B005T8N31Q?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00


Thank you CraftDan!

 

[kacknor]

My heat gun is a Harbor Frieght design. No attachments just a 5/8th or so round outlet. It's pretty precise where it puts heat, as long as I am careful where it's aiming I can get it darn close to foam or finger without worry.

JD

 

[PHugger]

SPONZ - That station looks great! And it costs less that my simple Weller even without the extra heater!
Very Nice!



Best regards,
PCH

 

[PHugger]

My name is Pete and I have a Tool Problem.
I love collecting tools and never hesitate spending money on quality tools.
Someone told me a long time ago - you will always buy cheap tools twice at least.
Cheap tools will do their best to hurt you.

Invest in tools, you will have them for a long time. Go cheap somewhere else.




Best regards,
PCH

 

[SP0NZ]

Crafty said that this is a good quality knockoff of a pretty expensive Hakko station (not sure which model). All I've done with it so far is turn it on and play with the controls a bit so far. It has a heat range of almost 900° F for the iron and the heat gun. Heats up in seconds and holds temp to +/- 1° C. With the heat gun on Auto, it turns on when you pick it up off the base and shuts off when you return it to the base. I'm really impressed with it. I should actually solder something with it now!

 

[kacknor]

I'm really impressed with it. I should actually solder something with it now!

Yes, you should!! Build something! lol

I have to admit to a little tool envy going on here, but for what I'm doing the 25 watt pencil and paste is working. Besides, I have a small bench. Really small. Have to move things to build, and it barely holds a sheet of foam (almost). That's a real nice setup.

JD

 

[OttoPilot]

I've gotta say, if I didn't already have a Hakko station, or didn't have an area dedicated to electronics one of these new SEEED soldering irons would be headed my way.

http://www.seeedstudio.com/depot/Mini-Soldering-Iron-US-Standard-ShapeBC2-p-2494.html

For what it's worth I like my Harbor Freight heat gun. Can't go wrong for ~$10.00. Things look so much more professional when there's no melted/burnt/sooty heat shrink.

 

[pressalltheknobs]

I have a similar setup to Sponz but in two boxes.
YiHUA 935
YiHuA 858D

On solder, rosin core lead based is the easiest to use. The "best" is supposed to be 63% tin, 37% Lead but I don't know off hand why it is better than 60/40.

Lead based solder is not used commercially any more because lead is toxic, accumulates in the body and causes brain damage. Basically not something we want long term exposure to or dumped into the environment from obsolete electronics.

For occasional RC use though it's much easier to use. Just be careful not to breath in the fumes any more than you have to and wash your hands after handling it particularly if you have young children in the house.

 

[str]

Back on topic

I was asking about solder, not soldering stations!

What mix rosin/tin?

What diameter?

What brand?

With flux pen?