ESC Solder Tabs - HELP!!

[Andysan]

Hello Ooplers,

I am wiring up a Nosram Matrix ESC and replacing the existing motor wires as they are too short. The two at either end of the ESC went on fine but the hole in the final tab seems too small for me to fit the wire in. Obviously I;ve tried to remove as much of the existing solder as possible using braid but I'm having no luck at all and am concerned that I may start to damage the ESC soon (the tab is starting to look a little wonky).

Is there a better way of doing this please, or something I'm doing wrong? Should I keep trying or stop in case I damage the ESC/tab? Using a 60W iron and a brand new wide flat tip. Not sure quite why I'm having so much trobule as the first two wires went in on the first attempt.

Cheers.

[teamxray]

bet your having trouble with the black wire if it is try trimming a few strands off then solder it in as the black wire is all ways thicker than the red wire

[shanks]

Originally Posted by teamxray

bet your having trouble with the black wire if it is try trimming a few strands off then solder it in as the black wire is all ways thicker than the red wire

interesting - never realised that !

solder suckers are also very useful for clearing tabs properly

[B&H Racing]

When I had this problem, I just soldered the end of the wire then made it nice and circular and into a bit of a point with a dremel sander

Went in not a problem

[coolcars782]

like "TeamXray" said, cant you just cut a few strands off the wire?

Carl

[Andysan]

Hi Chaps,

Thanks for your replies.

I had tried cutting some of the wire off and found that I was taking nearly half off in order to get it to fit. With some perseverance I was able to get some 14 gauge (I had been using 12 gauge) to fit.

I am still concerned I may have damaged a tab - I've tried a brushed motor and it appears to run OK, but perhaps a little underpowered compared to running it straight off a 7.2v battery. The dodgy tab is tab B, the one that goes to -ve with tab A. I cant try a brushless until the weekend and would like to put my mind at rest. Can anyone state whether the brushed motor would/wouldnt run if tab B was broken please? Would it just run at reduced power?

Thanks.

[Rich D]

On the Matrix/TC Spec you can help yourself by using a few tricks.....

Take the fan off if you have one fitted, bottom cover off and remove the radio board from the FET board. This stops you mauling up the plastic casing with the soldering iron.

Then you can turn whats left of the speedo upside down and stick it to the work surface with servo tape on the heatsink to hold it steady whilst you work ( overhanging the edge of the worktop of course )

The heatsink is not removeable and is attached to the fets with heat transfer paste/glue. No need to try and remove it.

The factory fitted 12 AWG will go back in just fine but you need to be careful when trimming up the ends so as to not "splay" the wiring apart. Its a close fit. I use a craft knife to remove 3mm of the silicone insulation from the end of the new wire. Do not twist the wire once stripped!

I tend to use 12 AWG for the battery wires and 14 AWG for the three motor wires. They are easier to work with both on the speedo and on the car and are still plenty big enough to cope with the loads.

You then need to carefully tin the end of the new cable usng decent solder ( the Schumacher stuff is good ). Only use a tiny amount and make sure that you have some wet kitchen roll to hand to keep wiping the tip of the iron clean.

So now you have 5 new tinned wires ready to refit to the speedo. You need to be careful not to apply too much heat. When you are setup right you only need to touch the soldering iron onto the board and you will find the wire slips right in. Make sure you have tinned the terminals of the speedo. You apply the heat from the same side as the FETS and push the new wire in upwards from underneath - thats the trick.

Make sure you keep wiping that tip and theres always a tiny amount of wet solder on it to help with heat transfer.

Do one at a time and pay attention to how hot the fets are getting. If needs be let it cool down in between. When you get good at it you wont be able to tell the difference between factory soldering and your soldering

Ive babbled on a bit but hopefully this will help you and others on here.

[Andysan]

Thanks Richard, thats very helpful for next time.

I'm going to try and run the brushed motor with the lead from tab B disconnected at the motor end in order to identify whether any current is coming along it - any danger in doing this please? Should the motor still run or not at all?

Thanks.

[Rich D]

Originally Posted by Andysan

Hello Ooplers,

I am wiring up a Nosram Matrix ESC and replacing the existing motor wires as they are too short. The two at either end of the ESC went on fine but the hole in the final tab seems too small for me to fit the wire in. Obviously I;ve tried to remove as much of the existing solder as possible using braid but I'm having no luck at all and am concerned that I may start to damage the ESC soon (the tab is starting to look a little wonky).

Is there a better way of doing this please, or something I'm doing wrong? Should I keep trying or stop in case I damage the ESC/tab? Using a 60W iron and a brand new wide flat tip. Not sure quite why I'm having so much trobule as the first two wires went in on the first attempt.

Cheers.

Be wary if the tab is bent as its only wafer thin copper on the PCB. Here are some pics of a speedo given to me by a lad at the club who pulled too hard on the wires ( not enough heat in the right place ) and wrote his speedo off !

You can see the break on the middle tab.

[Andysan]

Ouch! From that side on picture mine actually looks a fair bit worse than that.

[Rich D]

Originally Posted by Andysan

Thanks Richard, thats very helpful for next time.

I'm going to try and run the brushed motor with the lead from tab B disconnected at the motor end in order to identify whether any current is coming along it - any danger in doing this please? Should the motor still run or not at all?

Thanks.

Dont run it like that!

In brushed mode ....

C orange should go to +
B and A together go to -

Anything else and theres a good chance you`ll smoke your speedo.

[Rich D]

Originally Posted by Andysan

Ouch! From that side on picture mine actually looks a fair bit worse than that.

Theres a good chance its jiggered then im afraid dude ! If it isnt you`ll be lucky! As i said if you apply heat from the FET side and pull the wires downwards they just fall out easily. I learned from my own mistakes that the method i typed above is the best one

[Andysan]

Originally Posted by Rich D

Theres a good chance its jiggered then im afraid dude ! If it isnt you`ll be lucky! As i said if you apply heat from the FET side and pull the wires downwards they just fall out easily. I learned from my own mistakes that the method i typed above is the best one

Hmmm... thanks Rich. I tried it with B wire d/c-ed anyway before I saw your post and it didnt appear to run any different - it doesnt seem as smooth as when hooked upto the battery. The ESC seems to function fine though. Until I get a brushless motor this weekend is there any test I can do to confirm that any current is coming along this wire please?

Guess you're right, you do learn from your mistakes. Shame its always the expensive ones.

[Rich D]

Originally Posted by Andysan

Hmmm... thanks Rich. I tried it with B wire d/c-ed anyway before I saw your post and it didnt appear to run any different - it doesnt seem as smooth as when hooked upto the battery. The ESC seems to function fine though. Until I get a brushless motor this weekend is there any test I can do to confirm that any current is coming along this wire please?

Guess you're right, you do learn from your mistakes. Shame its always the expensive ones.

I would take it to bits and have a look to see if theres a crack in the PCB. That copper is only about 0.3mm thick for a guess so it doesnt take much to split it if you bend it.

As for working as is, you might find that its only using two of the three banks of FETS and thats why, im unsure.

I have no clue what the consequences of running it like that might be.

Good luck dude. Worst case scenario you can pick up a used matrix or tc spec on here for between 45 and 75 quid

[Andysan]

Cheers Rich, will wait a few days to test it and then report back.

[Rob_B]

Insted of taking the bottom of the esc you could always place a piece of flat metal against the plastic casing saves melting it.

[Andysan]

I'm pleased to report that the ESC lives! I hadnt got a hot enough iron to get rid of all of the dried on solder from the previous user so enlisted the help of my local hobby shop who have a much more powerful iron. Now its running sweet as a nut. My thanks to all who offered help & support.

Ciao for now,
Andy