Soldering!

[911hillclimber]

Spent a frustrating few HOURS connecting my micro brushless to the esc. The wire type used is the non-solderable wire, one fine strand for each motor lead and multi strand for each of the 3 black esc leads.

Can these wires be soldered or are they crimp only?

I have 40 amp iron, rosin cored solder etc but they will not tin, esp the motor strands which are so fragile I worry about reliability....

Thanks, Graham.

[Wingman]

The wires will be coated with a varnish (shellac) so that has to be scraped off to bare copper before they will take solder.

[Plummet]

Some wire is coated with a varnish. It needs to be carefully scraped off. Sometimes it can be burnt off in a flame.

This is often because inside a motor or transformer you need to get a lot of turns of the wire into a small space, so ordinary insulation would take up a lot of space, and also impede heat escaping.  The varnish provides enough insulation to allow the windings to touch each other without short circuiting.

Hope this helps.

 

Plummet

Edited By Plummet on 08/05/2020 16:51:29

[Simon Chaddock]

011hillclimber

Did you shorten the motor wires? They normally have a 'tinned' end that you can solder to easily.

The actual wire is now covered with a polyurethane varnish which is extremely tough and really hard to remove. You risk damaging the fine wire in the process.

It is unlikely they would crimp either as the varnish would prevent good or any electrical contact.

All you can do is VERY carefully scrape the varnish off the wire with a very sharp blade.

[Piers Bowlan]

Hi, What type of solder are you using, is it Lead free? Very 'green' but from what I have heard it doesn't work too well. I don't have any so I am not speaking from personal experience, I prefer to use 'full fat' leaded!

The other thing is that these thin wires will wick the heat away very quickly which can lead to dry joints. You don't just need a hot iron but a physically LARGE iron works best with thin wires (not just high wattage).

Edited By Piers Bowlan on 08/05/2020 17:52:04

[Rob Fairweather 1]

My old gaffer, during my apprenticeship always said 'cleanliness before godliness with soldering'

[Peter Miller]

The solder used for tinning these days is lead free and is pretty useless for normal home use.

A 40 watt iron is overkill in a big way for a job like that. a 25 Watt iron is fine and for a micro motor a 12 Watt should be more than adquate.

[flight1]

with such thin wire you have proberly burnt the flux away before it could do its work with a 40w iron

and also make sure it's claen no coating like the others have said. You can not beat good old tin/lead solder though.

[911hillclimber]

Thank you all v much.

I have a smaller iron so will try that tomorrow.

solder is rosin core type and I will scrape the wires (again) just in case.

will report back!

Graham.

[Geoff S]

In another life I used to wind small coils for TVs and radios in the manufacturers service dept as a sort of apprentice and needed to solder enamelled copper wire as part of the process. I had a small flame and heated the ends of the wire until they just glowed and quenched them in meths. That burned off the enamel and left a clean copper finish that was easy to solder. I'm pleased to say that that part of my training only lasted a few weeks. It was pretty tedious.

The wire in a motor (or any coil) has to be insulated or the current won't bother flowing along the windings (obvious, I know) and whilst early radio coils were often cotton or silk covered, enamel is the way to go. Moreover, to make life even harder the wire is often multi-stranded (known as Litz) to keep resistance low because of the so-called skin effect where at high frequencies the current flows near the surface. That's even harder to solder.

Rob Fairweather's gaffer hit the nail on the head - cleanliness is before godliness when soldering.

Geoff

[911hillclimber]

Quickly loosing the will to carry on!

You were all right about the varnish, must have been formulated by NASA. Lots of very careful razor scraping has worked.

I made a hi-tech soldering station with 2 old wooden cloths pegs spaced 15mm apart. What a god-send to this adventure, and found my 20W iron which is about 50 years old or more, still smells and works.

High lead solder and I can now get reliable soldered joints!

HOWEVER!

I have soldered the new micro motor to the esc and bound the TX/RX and charged the battery etc etc and can get the beeps x2 and the rapid beeps x 3 and no motor working.

Have tried a million combinations of these 3 wires, and nothing.

What an I doing wrong?

[Denis Watkins]

Reverse the throttle Graham

[911hillclimber]

Tried, no change...

[911hillclimber]

GOT IT!

Reversed the throttle stick, nothing until I moved the stick to max up and the motor is alive. The range on the stick for this micro motor is VERY different to the much larger motor in my buccaneer.

 

Now have the motor turning anti clock and stationary with the stick fully down.

 

Thank you all esp Dennis! (to my rescue again...)

Edited By 911hillclimber on 09/05/2020 17:09:53

[911hillclimber]

Nearly done.

This build has not been as interesting as my recent BB Buccaneer simply due to the size, bit too small for my garage DIY mechanic hands!

[David Hazell 1]

Lovely photo of the sun shining through the tissue!

[Former Member]

[This posting has been removed]

[911hillclimber]

Or do my next one Rubber!

Take your point, the make shift jig was a god-send.

[Simon Chaddock]

01hillclimber

That looks like one heck of a long motor shaft extension . It means the weight of the prop is a very long way forward of the motor bearings and the motor mounting flange itself come to that or am I missing something.

If there is a long overhang you may have trouble with prop balance or rather the inability to achieve.it.

[911hillclimber]

Mmmm...

wish you hadn't said that.

never gave that a thought. Not easy to correct now without knifing the plastic nose off.

Im sure you are right....

[911hillclimber]

Well, with that bee in my bonnet, too the knife to my plastic fragile cover, cut it off, made a 12mm spacer, glued and re-mounted the engine and back on with the cowl.

Looks better.

Need to sleeve the prop hub from 5mm to 3mm to match the motor extension and all done.

[911hillclimber]

All done.

Another model about to be ordered, but will be built as a static skeleton.

[Shaunie]

A lot of the enamelled winding wire is “self-fluxing” with a fairly hot iron hold the tip on the end of the wire to get heat into the copper and the enamel should burn back. It should not be necessary to scrape the enamel off by hand.

[Dickw]

Posted by Shaunie on 13/05/2020 22:48:58:

A lot of the enamelled winding wire is “self-fluxing” with a fairly hot iron hold the tip on the end of the wire to get heat into the copper and the enamel should burn back. It should not be necessary to scrape the enamel off by hand.

It may be on some of the cheaper motors, but motor windings tend to get hot so most motors I have come across these days use a high temperature enamel, Unless you have access to some dodgy chemicals scraping the enamel is the only way. On a motor with windings made from lots of fine wires it can be a real pain!

Dick