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Molex microfit madness!

kyle Lee

Member
Has anyone, after investing in a proper Open Barrel Crimp Tool for Molex pins and studying the abundant information on how to get a good crimp and after thinking that you have crimped it properly, had problems inserting the Micro-fit pins into the actual plugs (after trying all four different possible orientations more than once)?

I am referring to the RV-12 trim wire upgrade. Detailed on Pg 11-07 revision 3, dated 10/18/11, this shows the fitting of Molex Micro-Fit pins into the ES-00044 and ES-00045 Molex Plug, 6 Position Micro-Fit(s).

I have installed the male Micro-Fit pins onto the ES-MSTS-T3-7A-2 wire. These successfully went into the ES-00044 connector. However, upon trying to do the same with the mating end (WH-P30 Trim Wires) and installing the female ends into the ES-00045, I am unsuccessful.

Any suggestions on how to be more successful with the female ends? ;) (Insert joke here but real suggestions would be most helpful)
 
It was a struggle

I ended up abandoning the plug bodies and using heat shrink on each wire, still using the molex pins, and covering each assembly with the shrink. I used tie wraps to secure the completed connections and I have 24 hours of flight logged and the connections are working well.

I tried and tried to get the pins to properly seat in the small plug but I just could not so I tried this method. I will continue to evaluate over time.
 
Kyle... It has been a while since I did that step. I do not recall a problem getting the pins into the connector bodies. I do recall difficulty crimping the wires. I tested the crimped connections, the connectors and servo motor using a motorcycle battery.

Jeff
 
Yep, I had a lot of problems with them. I could not get them to work either so I used a DB9 connector with crimp pins and then used heat shrink to hold it together.
 
More detail?

I am building a 7 and only using the Molex for Whelen wiring, but I did tray a little research on Molex product and found a large number of pin dimensions. What exactly is the issue, is the pin diameter correct for the body? Caliper the end, and try a drill bit the same size. Will it not click in place? Is it too hard to push before full insertion and there is fear of bending it?

Have you destroyed any in the process? Too much push in force?

I have found that the right orientation and force will get "a" job done with these connectors, all connectors, but a few have been sanded down on the belt sander to see how the inside was made to determine what was "correct". Once "correct" was determined the connectors were not so much of an issue.

Even when known, I have had some very stubborn d-sub pins that did not want to exit the body, and persistence was needed.
 
Those pins are fussy. I've found my most common mistake is to accidentally crimp the latching flanges that splay out from the pin or barrel housing at about a 30 degree angle.

If you crimp those it both deforms the pin making it hard to insert and prevents it from latching into the molex housing because you've destroyed the latching flanges. There are only two locations to crimp: the outer one that captures the wire jacket and the next one in that makes contact with the stripped wire.

Finally, I like to hit the inner crimp with a tiny bit of solder - but only after I'm happy with the crimp, not in lieu of a good crimp. Too much solder and the pin won't insert.

For low-amp stuff (< 3A @ 14V) I now use D-SUB connector. Much less fussy. If I know I can get a small cutter back on the connecters after installation I will sometimes use tie-wrap to secure them together if there is insufficient room for back-shells but, without a back-shell, there may not be enough strain relief on the wires in case the bundle gets pulled.
 
Forget Micro-Molex!

Has anyone, after investing in a proper Open Barrel Crimp Tool for Molex pins and studying the abundant information on how to get a good crimp and after thinking that you have crimped it properly, had problems inserting the Micro-fit pins into the actual plugs (after trying all four different possible orientations more than once)?

I am referring to the RV-12 trim wire upgrade. Detailed on Pg 11-07 revision 3, dated 10/18/11, this shows the fitting of Molex Micro-Fit pins into the ES-00044 and ES-00045 Molex Plug, 6 Position Micro-Fit(s).

I have installed the male Micro-Fit pins onto the ES-MSTS-T3-7A-2 wire. These successfully went into the ES-00044 connector. However, upon trying to do the same with the mating end (WH-P30 Trim Wires) and installing the female ends into the ES-00045, I am unsuccessful.

Any suggestions on how to be more successful with the female ends? ;) (Insert joke here but real suggestions would be most helpful)

Kyle, I had the same problem(s). I've been a big MOLEX fan for a long time, but I'm afraid they blew it with this 'micro' series. I used the old nylon style with 0.062 pins for the trim motor. I'll probably use a DB9 for the headset wires. Good luck!
 
Well, it is a bit more reassuring to hear that others have experienced the same thing. I agree with Gossend that the larger Molex pins were a breeze but these Micro series are a pain.
In response to BillL, I believe that the pin diameter is the right size as the complete set came out in the RV-12 Trim Wire Upgrade package. We have not destroyed any in the process but originally started with light force moving through the full spectrum into grunting and cursing (also used the tool that comes supplied to assist with not much more luck). It just seems like it does not go in deep enough to make the "click" and lock.
I might go the same road as many of you experienced builders have and look at other options for wiring this together.
Thank you all for your input.
 
I am installing the light kit on my D180 equipped 12. Am having some difficulty with small male and female pins for Molex, but find if I use a little wiggle force with a small needle nose pliers they go in and lock in place.
What is a DB9?
Dick Seiders
 
Molex crimp tool

I'm trying to find the right tool to crimp the Micro-Fit pins for the pitch trim servo (page 11-07). I've been through most of the Molex threads and don't seem much smarter than I was before. Some of the crimp tools refer to .093 pins, some to .061 and some don't mention size. They all seem to accommodate at least three sizes just judging from the picture. The problem is, the pins provided in the kit don't identify the size.

I saw a reference to a specific tool hnere http://www.vansairforce.com/community/showpost.php?p=876761&postcount=4 but that was a general Molex discussion and can't tell whether it covers the Micro-Fit pins.

Here are some tools I've been able to locate but not sure if they handle the right size:
http://www.mouser.com/ProductDetail...KRjOtAcY-Xhcii-Wqu23I3scg-k2N_TtGYaAiL_8P8HAQ
http://www.mouser.com/ProductDetail...ha2pyFaduiQ3nLSy%2bWOR87z7oMtSf/ourx5XpqEmx4=
http://www.steinair.com/storedetail.cfm?productid=292

So, what crimping tool is appropriate for these Micro-Fit pins?

Don't know what other Molex is in my future in my -12 build. Will the same tool work for all?

Thx
 
I'm trying to find the right tool to crimp the Micro-Fit pins for the pitch trim servo (page 11-07). I've been through most of the Molex threads and don't seem much smarter than I was before. Some of the crimp tools refer to .093 pins, some to .061 and some don't mention size. They all seem to accommodate at least three sizes just judging from the picture. The problem is, the pins provided in the kit don't identify the size.

I saw a reference to a specific tool hnere http://www.vansairforce.com/community/showpost.php?p=876761&postcount=4 but that was a general Molex discussion and can't tell whether it covers the Micro-Fit pins.

Here are some tools I've been able to locate but not sure if they handle the right size:
http://www.mouser.com/ProductDetail...KRjOtAcY-Xhcii-Wqu23I3scg-k2N_TtGYaAiL_8P8HAQ
http://www.mouser.com/ProductDetail...ha2pyFaduiQ3nLSy%2bWOR87z7oMtSf/ourx5XpqEmx4=
http://www.steinair.com/storedetail.cfm?productid=292

So, what crimping tool is appropriate for these Micro-Fit pins?

Don't know what other Molex is in my future in my -12 build. Will the same tool work for all?

Thx

I bought a set of Molex crimpers locally, at Fry's Electronics. Great quality, fair price, and they worked well for me. Don't recall the part number. If you don't have a Fry's close by, frys.com will be an option for you.

*** I spent a tremendous amount of time studying the Molex crimp connector data in the plans. Then I looked closely at the connections on Stein's harnesses that they send with the avionics kit. Both of those avenues helped me to make good terminations on the connectors. By the way, Fry's also sells the Molex micro pins for pennies. I bought a ton of them for just a few bucks. That way, if I had a questionable crimp, I had PLENTY of spare pins to re-do them.
 
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Thanks, Gary. Got that right about spending a huge amount of time with the plans and other connector info sources. I spent a career around avionics connectors of all sorts but these are way smaller than I've dealt with.

We don't have a Fry's nearby but I checked their site. Couldn't find any Molex crimping tools.

The pins I saw on Fry's seem to come in .062, 093 and larger sizes. That's consistent with what I saw on other sites when I was looking for crimping tools. I assume the size refers to the diameter of the pin? If so, these micro-fit pins seem to be around .030, way smaller than anything I saw at Fry's.
 
Thanks, Gary. Got that right about spending a huge amount of time with the plans and other connector info sources. I spent a career around avionics connectors of all sorts but these are way smaller than I've dealt with.

We don't have a Fry's nearby but I checked their site. Couldn't find any Molex crimping tools.

The pins I saw on Fry's seem to come in .062, 093 and larger sizes. That's consistent with what I saw on other sites when I was looking for crimping tools. I assume the size refers to the diameter of the pin? If so, these micro-fit pins seem to be around .030, way smaller than anything I saw at Fry's.

Send me a PM with your address, and I'll loan you my crimpers for however long you need them. They aren't anything really fancy but they sure worked better than the original set I got with an RV tool kit back in the day.
 
Thanks Gary. I'm pretty new here and just learning what a great community this is. PM sent.
 
Thanks Gary. I'm pretty new here and just learning what a great community this is. PM sent.

No problem, Tom! I won't need them for the foreseeable future (I'm flying a high performance C-172 for now :rolleyes:) and they're just sitting in my toolbox.

Got your address and they'll go out to you tomorrow! Glad I could help.
 
Those crimpers we sell seem to be a good fit and work fine, though they may take two individual crimps instead of one (that the more expensive tools will do). Stay away from the automotive looking ones, they will spell trouble for you sooner or later...and the more expensive one are just, well, more expensive! :)

Cheers,
Stein
 
No problem, Tom! I won't need them for the foreseeable future (I'm flying a high performance C-172 for now :rolleyes:) and they're just sitting in my toolbox.

Got your address and they'll go out to you tomorrow! Glad I could help.

Gary, PM sent ...
 
I notice the Rv12 kit comes with silver colored connectors for the wires. I fly RC turbines and we always use the gold colored connectors as we were under the opinion they were better. I have many of them. Are the gold better than the silver? Is it OK for me to switch to the gold ones?

Bob
 
I do not know about pins. But for switches, gold contacts are for low current, say 0.5 amps or less. Silver contacts are for higher current.
Joe Gores
 
Solution for Molex Micro-Fit Madness

Reference Micro-Fit connector for stabilator servo and RV-12 Kit Assembly Instruction, page 11-07, Revision 3. I had a terrible time trying to insert the ES-00047 Molex Micro-Fit pins into the ES-00044 plug.

The pins only insert in one orientation, and I could put them in with my fingers, but they would pull right out. After about 30 minutes of frustration, I used the red and white pin insertion/removal tool that came with my avionics kit to press the pins more deeply into the plug. That seated them.

There was no problem with the ES-00046 sockets and the ES-00045 receptacle. The sockets just latched in when I inserted them with my fingers.
 
Like the OP of this thread, I was having a **** of a time getting the female pins of the molex microfit into the plug bodies. Turns out I had the SL Series female pins and not the Microfit 3.0 style. The SL series have a single wing/latch on the top, whereas the Microfit 3.0 have one on each side. Once I had sourced the correct female pins, they went in fine. I found the standard Stein open barrel crimper a little wide for these, so I have been using my JST-SH crimper that is normally used for model RC servos, which seems to work well for this application.
https://hobbyking.com/en_us/hobbyking-jst-sh-connector-crimping-tool.html?___store=en_us
I've been using the small position on this crimp tool for crimping 22AWG wires into these pins. It crimps both the insulation and the wire at the same time, which I'm not such a big fan of, but all crimps thus far pass the pull test and seem to fit the housing bodies.
Tom.
 
I had to do a bit of research when i mangled my molex connector for the landing light.

I found that they discontinued that nylon part.. I ended up using a MicroFit connector instead and I made sure the amp rating was sufficient.

Meanwhile, the microfit on the AST i believe was recently replaced with a DB-9 connector.. ?
 
I feel your pain ... wear glasses ... seriously ... that solved my microfit molex crimping issues.

There are 3 sets of "dog ears" or "tabs" on the pins. The two wire-facing tabs are for the wire housing and the exposed wire. Then, there is another set, almost impossible to see, forward of those, that you absolutely have to make sure you don't tweak or bend as that set is what grabs the inside of the housing. It is *really* easy to bend them if you aren't paying attention to how you have them oriented in the crimping tool and it doesn't take much to render them useless.

Once I figured this out I can do it perfect every time.
 
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Grind Crimper Face

I found I had to grind down the crimper face so it fit between the wings that crimp to the insulation and the wings that hold the pin in the connector socket, and just crimp the wings that connect the wire to the pin; those little pins are a pain to work with
 
subD pins. (as in, period) :)

You can use the crimpers you already have for... subD pins. The machined ones are gold plated, as Joe mentioned a few years ago in this thread. Someone else back then mentioned that the ones in the kit were 'silver'. If they were Molex, they might have been silver *colored*... but unlikely they had silver plating.

Anyone know if the smaller CPC series connectors take subD pins & tools, or do you need dedicated tools for them?

Charlie
(did I mention that across multiple careers in electronics, I have an ever growing hatred for molex style connectors?)
 
CPC series 2 connectors (8-63 pin) use standard d-sub pins & sockets. The other CPC series use different pins.
 
The majority of the generic crimpers have fingers .150" to .180" thick. The mini Molex pins measure .130" from the rear detente protrusions to the insulation crimp. The choice is grind the crimper fingers down or crimp the wire and the pin simultaneously. As me how I know this :)


It takes two steady hands to keep the wire correctly positioned if you elect to go the unicrimp way. If you do either and do not disturb the retention protrusions they will stay in position well. I have converted to all 9 pin D Subs because the little weight savings with the Molex is not great enough to offset the addded hassle of crimping the Molex pins.
 
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