I need a little help on the best way to solder an MPX plug. What I'm trying to fabricate is an extension from my ECU to the ECU battery. I'll only need two wires, red and black. In the past when I've stripped off the heat shrink on MPX plugs I've seen where the wire (pos or neg) is soldered to three pins. How do you do this? Anyone know of any videos of this? I can't see how I can heat all three pins at once, or even two, to get a good solder joint.

Thanks

Great quest. I am about to do this as wel.....

I saw these the other day that look quite interesting but I haven't tried them

http://shop.rc-electronic.com/e-vend...t=12&c=46&p=46

I'm not very good at soldering but I hold the wire place with some form of clamp (against at least 2 pins if you can) and let the solder flow. The heat carried in the solder tends to heat the pins enough for a bond. You can tin the pins first to help.

Hi. Heres how I do it. Cut 2 small pieces of brass tubing same depth of the 3 plug wires . Tubing must be of a size that is a snug fit between the 3 wires. Do this both sides. Solder tubes to plug wires. Now you can solder your extension wires inside the tubes without any bother. If the extension wires are really heavy you can use larger size tubing to surround the mpx wires and solder again on the inside but this is not as easy to do.Hope this helps. Paul.

Hi

You don't need that. Just heat a pin or 2 with the soldering iron and then let a bit of solder flow. After that heat the cable (without the silicon cover...) and let a bit of solder flow.

Then put the wire in the plug in a way that it hits the 3 pins. Heat the all thing up and you're done. Don't forget to put some heatshrink before

Siclick - I use these to make aileron and flap extensions in the same plug. Great thing...

Good luck

Nuno

I have used the Emcotec pcb's they are very good and neat but not cheap. If you are soldering a power cable to MPX here are a few tips.

Gently bend over the three pins you require soldering to so the tips make a kind of wigwam shape, just make sure to leave enough of an opening to get your wire inside.

Next, and I have found this quite crutial is to connect another MPX to the one your soldering (opposite naturally) then hold in a clamp or similar, this other connector helps remove some heat from the plug you are soldering and helps keep the pins aligned should the plastic case soften a bit during the process.

Get a good hot iron and touch one or two of the pins and feed in a good length of solder as quick as possible, you should be able to 'blob' together all three pins. Solder the end of your wire, place the soldered wire on top of the 'blob' between the three pin tips, heat the 'blob' while gently pushing the wire down, once the solder melts and the wire drops in give it a second or so for the solder to fuse and remove heat. With any luck you should have a good joint across three connectors and a plug in one piece.

marcs

Bend the three pins toward each other just enough to hold the wire in place, then solder.

Does anyone know if these are available in the US or Canada?

Thanks for the suggestions, guys. The 'wigwam' with a blob on the pins/good blob on the tinned wire method seems to work pretty good for me. I just worry about getting a cold joint when I let blobs remelt and flow. I have not tried the brass tube methos, but it sounds reasonable.

I did discover the need to plug in the corresponding male/female plug. My first attempt I did not do this, and a couple of the recptacle pins (I was working on a female plug) 'walked' out of the plug a bit and protruded out, rather than being flush with the plug end. I tried again with another plug, this time with the male side plugged in, and there was no problem at all.

If you have something like a set of 'extra' hands I think they call them you can tin the wire and hold it inside the wigwam and solder in one go - just depends on your selection of tools.
I also recall you can buy red MPX plugs with a small ring already in place around the two sets of three pins, not sure where I saw them but have had some in the past.......

marcs

Bought the new soldering jig from DreamworksRC. Best $ 48 Ive ever spent.

Points in summary are
1 Tin the wire with a good glob of solder. Brief heat exposure and solder a ball of solder onto the wire which has been stripped of its insulation. Long exposure will allow the solder to wick up the wire and stiffen it to make it more brittle. Brief heat and small gauge solder will work the best.
2 Tin the pins with solder as well. All of them that will be connected to the wire.
3 Heating the wire (greater mass) will melt the solder on the pins and the connection is made quickly, without melting the plastic of the Multiplex plug.
4 Using the plugs mate will keep the pins aligned if the plastic is over heated. Brief heat exposure to the wire minimizes this risk.
5 I use Hysol to cover over the exposed wires and insulation, very much like the power box Deans and Multiplex ends that are molded.
6 Wire larger than 16, such as 14 or 12 gauge can also be used if the wire is well tinned with solder and the compression is brief.
7 The jig i use are two plates of half inch granite slabs that hold pieces quickly and without clamps or widgets.

Pretty good summary. The tip temperature is also important at around 350 C max if using a 1/8 tip. If you have a flux pen applying some would also help. The flux should show as light brown after tinning. If it burns black its not gonna flow very well. If you cant do the steps above in 2-4 seconds back off, allow to cool and try again.
The hysol will work real well to prevent fatigue. With a little help from a heat gun it can be made to flow nicely round all the wires evenly.

I get the wife to hold the wires in place while I solder them. No intelligence required & she works cheap. Other than the odd "ouch that's hot" it works fine.

Great info! I like the Hysol idea. That has always been a concern with me, using solder on the pin also as the mechanical hold of the joint. That's always bothered me about a Deans plug.

Sluggo,
I have not tried the Hysol technique, but it sounds good. When I made my multiplex plug for the battery/ECU connection I used the bent the wires as others hve described as a 'wigwam', put shrink wrap on the wires and then 'painted' the multiplex plug and wires with liguid electrical tape from Home Depot. I'll post a pic when I get home this evening. If you put a wrap of electrical tape on the plug and about 3/4 inch down the wires, then apply the liquid tape, it makes a nice appearance, further insulation between wires and relieves stress on the solder joint in the plug. For what it's worth from one fighter pilot to another!
Regards,
Gus

Gus - Thanks for the tips. I've seen the liquid tape, so I'll give that a try. I did a pigtail earlier using the 'wigwam' method and had good results. I had put heat shrink over the soldered connection, but I'll add the liquid tape over a wrap of electrical tape for good measure. Pics will be great when you get a chance!

I appreciate a good wingman looking out for me...can't beat good 'mutual support'

V/R,
Sluggo

Sluggo,
Sorry, crummy pic, but you get the idea; bend the three MPX prongs so the wire fits in, tin all, solder, apply shrink wrap, then I applied the liquid tape from Home Depot and you have a fairly tidy connection.
Regards,
Gus