I don't have a Soldering iron?

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Apryl

New Member
I'm repairing an HTC Desire 816 that had a broken screen and LCD. I fixed all of that but the battery terminal was some how pulled away from the circuit board. I need to solder the terminal back onto the circuit board in order to charge the phone. However, I don't have a soldering iron. Is there any other way I can fix this? Is there an alternative to soldering? I'd order one, but it would take way too much time to get here. My client needs their phone back asap.

rickselectricalprojects

New Member
There isn't really a substitute for a soldering iron when it comes to delicate electronics work.
Your local hardware store will probably sell a soldering iron.

strantor

Active Member
There's no good reason not to have a soldering iron, especially if you're going to be doing repair work in a professional capacity as it sounds like. And keep in mind that a soldering iron can be used on more than just the occasional PCB repair, like this for example; I splinted my broken key back together:

If you can't stomach the purchase for "just this one" repair (albeit an insignificant price, IMO), then maybe you could get a tool that does more than just solder. For example, this is what I use for soldering when I'm away from electrical power source; It's actually a small butane torch with all sorts of applications, one of which is a removable soldering tip:

IMO every person should have a soldering iron. There is no substitute

zahwi

Member
I'm repairing an HTC Desire 816 that had a broken screen and LCD. I fixed all of that but the battery terminal was some how pulled away from the circuit board. I need to solder the terminal back onto the circuit board in order to charge the phone. However, I don't have a soldering iron. Is there any other way I can fix this? Is there an alternative to soldering? I'd order one, but it would take way too much time to get here. My client needs their phone back asap.
You can use a copper wire of 2 to 4 mm diameter and heat it on a flame until it melts the solder then apply it to the the broken joint. You may have to repeat it several times.
This is how they used to solder in the old days.

dr pepper

Well-Known Member
If you do the above keep the 'tip' away from the yellow flame, that black sooty cack will make it hard to use, just extend the tip outside the flame.
Allthough the 'tip' on the vid looks like copper wire, the fact it stuck to a magnet and it can stand the heat of the flame makes me think its gas welding wire, which is copper coated steel.

Mikebits

Well-Known Member
I splinted my broken key back together:
I like that, I have the same problem with my truck key. My electrical tape fix keeps coming off, I'm going to use your trick. Awesome

strantor

Active Member
I like that, I have the same problem with my truck key. My electrical tape fix keeps coming off, I'm going to use your trick. Awesome
Yeah that rubberized plastic (plasticized rubber?) is something that in my experience is impossible to glue back together so I did that.

I may be wrong, but my approach was to use the hottest iron possible and go as fast as possible, to hopefully "flash heat" the copper and avoid melting the crap out of the plastic. I used the butane torch iron, with the sides glowing red. I did melt the plastic a little, but not bad. it's a 12AWG solid core wire splint with ethernet conductor wrapped around.

Beware the plastic/rubber will get soft and try to follow gravity until it cools. Good thing I was holding it in my hand and didn't have it clamped in a vise, or it would have sagged off to the side.

gophert

Well-Known Member
I like that, I have the same problem with my truck key. My electrical tape fix keeps coming off, I'm going to use your trick. Awesome
There is a proper glue for everything. You would need this one (about $3 at most hardware stores - only available in the past 2 years or so. strantor Active Member There is a proper glue for everything. You would need this one (about$3 at most hardware stores - only available in the past 2 years or so.
I should have known. I should have just asked you before I went brute force. You are the plastics expert.

gophert

Well-Known Member
I should have known. I should have just asked you before I went brute force. You are the plastics expert.
It is still "super glue" and very rigid. It tends to bond well to the plastic and strong for sheer strength measurements - but not good in peel strength and dynamic loads. I think it would have been find to fix your key unless you take it on/off a key-ring frequently. I guess a key would survive fine if it just hangs on a ring - there is a reason it broke in the first place.

jpanhalt

Well-Known Member
Come one, I am NOT sold. "Super glues" are base catalyzed. It has been known since last century that some woods are acidic and some plastics are non-reactive by nature. They cannot be bonded by super glue easily. Dust them with baking soda, and they glue just fine. PE and PP plastic surfaces are very inert. There are lots of catalysts marketed for super glues on the market. I have a heptane solution of a catalyst, again from the 1900's that works with PE.

You can also activate the surface for PE and PP with a simple butane/propane torch. Just pass the plastic through the blue to clear portion (where there are lots of radicals -- not the political type) and the surface will be activated. Teflon is a bit harder to do, but I have also been doing that for a long time with a proper surface treatment (sodium dissolved in naphthalene + a secret solvent).

Now, for $3 and a one time use, I would probably go with LocTite too. It is a great corporation and Cleveland based, until it was bought by Henkel. This is just to bring a bit of reality to the "amazing" advertisement. John dr pepper Well-Known Member Most Helpful Member You'd be handy where I work jp, we extrude pe, pp, polyolefin and a few others, and laminate foil and other materials. jpanhalt Well-Known Member Most Helpful Member Thanks, but I am happily retired. This laconic comment by a chemist has stuck in my mind for years: "The problem with using Teflon as a non-stick surface is that it doesn't stick to anything." John gophert Well-Known Member Most Helpful Member Come one, I am NOT sold. "Super glues" are base catalyzed. It has been known since last century that some woods are acidic and some plastics are non-reactive by nature. They cannot be bonded by super glue easily. Dust them with baking soda, and they glue just fine. PE and PP plastic surfaces are very inert. There are lots of catalysts marketed for super glues on the market. I have a heptane solution of a catalyst, again from the 1900's that works with PE. You can also activate the surface for PE and PP with a simple butane/propane torch. Just pass the plastic through the blue to clear portion (where there are lots of radicals -- not the political type) and the surface will be activated. Teflon is a bit harder to do, but I have also been doing that for a long time with a proper surface treatment (sodium dissolved in naphthalene + a secret solvent). Now, for$3 and a one time use, I would probably go with LocTite too. It is a great corporation and Cleveland based, until it was bought by Henkel. This is just to bring a bit of reality to the "amazing" advertisement.

John

I didn't say the Loctite pretreatment was the only option, it was just an easy-to-describe option.
So, what's in the magic heptane solution?

jpanhalt

Well-Known Member
I don't know, it was a gift -- maybe from a chemist at Loctite. My guess is an organic base. I would use something nice and lipophilic, not a quaternary amine.

Ordinary "kicker" as used by modelers might work. I use the stuff that smells good.

John

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dr pepper

Well-Known Member
If you've worked on a machine that extrudes teflon you know it sticks, like smelly stuff to a blanket.

Sometimes I wish I was semi retired, with a nice little cottage industry.

gophert

Well-Known Member
I don't know, it was a gift -- maybe from a chemist at Loctite. My guess is an organic base. I would use something nice and lipophilic, not a quaternary amine.

Ordinary "kicker" as used by modelers might work. I use the stuff that smells good.

John
You are on the right path...