Mueller BU-27

[N00bArmorer]

I believe that the Mueller General Purpose Clip (Clip link) is the one which most armors recommend for body cord and mask cords (Donald, I think you named this one as the one you use exclusively). I'm just wondering if this clip complies with the rule:

"the clip must leave a free space at least 8 mm long by 3 mm high"
m.29 Sept 2005 ed. USFA Rule Book.

Also, I have started making my mask cords with EDS Coil Ground Cord (Click here). This cord is relatively thin, but it's multistranded highly flexible wire as a core and seems to work perfectly once to you get the hang of stripping off the molded insulation. Does anybody see any problems with this cord? Also, I was once told by I believe Carl Oberg that the 30cm to 40 cm long rule for mask cords is interpreted for coil mask cords as being the coil mask cord must be able to stretch as long as 30cm to 40 cm, not that the actual linear amount of wire must be 30cm to 40cm. Is that true?

I understand that my questions might be nit picky, but I wanted some by-the-book armorer interpretations of the rules just to be safe in the future.

[fencerbill]

I believe that the Mueller General Purpose Clip (Clip link) is the one which most armors recommend for body cord and mask cords (Donald, I think you named this one as the one you use exclusively). I'm just wondering if this clip complies with the rule:

"the clip must leave a free space at least 8 mm long by 3 mm high"
m.29 Sept 2005 ed. USFA Rule Book.

Also, I have started making my mask cords with EDS Coil Ground Cord (Click here). This cord is relatively thin, but it's multistranded highly flexible wire as a core and seems to work perfectly once to you get the hang of stripping off the molded insulation. Does anybody see any problems with this cord? Also, I was once told by I believe Carl Oberg that the 30cm to 40 cm long rule for mask cords is interpreted for coil mask cords as being the coil mask cord must be able to stretch as long as 30cm to 40 cm, not that the actual linear amount of wire must be 30cm to 40cm. Is that true?

I understand that my questions might be nit picky, but I wanted some by-the-book armorer interpretations of the rules just to be safe in the future.

What I have seen done is that the wire is laid on a table and pulled by one end for a few inches. The distance between the alligator clips must then be from 30cm to 40cm long. The wire is free, not stretched.

Incidentally you will find the steel Mueller 27 will last longer in use than the copper Mueller 27C.

For steel Mueller 27 clips, you will find it difficult to solder unless you scrape, scuff, wire brush or use some other method to get through the finish as manufactured.

[Purple Fencer]

For steel Mueller 27 clips, you will find it difficult to solder unless you scrape, scuff, wire brush or use some other method to get through the finish as manufactured.

Argh!!! I wish I'd seen that before coming to work today....I just soldered 30 Mueller 27 clips for my new body cords. I thought my difficulties were just my poor soldering skills...

Got 5 more to do tomorrow (ran out of clips)...I'll see if I can throw my Dremel onto the remaining clips and get that finish off.

'Course, UNLIKE Uhlmann, I'm actually USING the screw the clip comes with, so the solder's a backup, NOT the primary connection.

[Purple Fencer]

I believe that the Mueller General Purpose Clip (Clip link) is the one which most armors recommend for body cord and mask cords (Donald, I think you named this one as the one you use exclusively). I'm just wondering if this clip complies with the rule:

"the clip must leave a free space at least 8 mm long by 3 mm high"
m.29 Sept 2005 ed. USFA Rule Book..

Quote the entire paragraph, dude:

"The crocodile clip must be robust and ensure perfect contact with the
conductive jacket. Its width at the point of contact must be at least 10
mm; the inside of the clip must leave a free space at least 8 mm long
by 3 mm high."

I measured the ones I just soldered...they measure about 13mm across the face (outside measurement), 9mm of clear space from the back of the teeth to where the parts crossover, and 3.5 vertical in the jaws...so yeah, it passes.

[N00bArmorer]

Thanks for the measurement check Sam. I just wanted to make sure the gap on the 27 was enough. Has anybody checked if any of the other clips that Mueller makes fall in line with the specs also? I'll bring over some my new coiled mask cords for you to take a look at next time I see ya Sam.

Bill, thanks for the tip about roughing up the surface and the insight on the length issue.

[KD5MDK]

9mm of clear space from the back of the teeth to where the parts crossover,

Is there any need to consider the spring between the two halves in this measurement?

[Purple Fencer]

Is there any need to consider the spring between the two halves in this measurement?

I don't think so...the rule seems to be designed to ensure there's enough clip to grab on securely to the lame...the spring's behind the crossover, so you can't get the lame back there anyway.

[DHCJr]

The spring is behind the gap, so it has no effect on the measurements. Until the last 10 or 15 years, the Mueller 27 was the standard clip for most major brands. The current cords use a clip, that has a tendency to come apart. Not a good sign.

There is a reason. Look at a Mueller clip and you will see the tabs connecting the 2 pieces are twisted, thus locking them in place. The others are just folded over. What you can do to make them last longer is too twist the connections.

On the cord you mentioned, it is a good cord, except for the cost and as you can see, buying just the cord is not an option. They only sell it with the connectors, which you cut off and throw out. A little more difficult to solder, but not to bad.

Yes it is best to rough up the clips to prep them for solder.

[Purple Fencer]

The spring is behind the gap, so it has no effect on the measurements. Until the last 10 or 15 years, the Mueller 27 was the standard clip for most major brands. The current cords use a clip, that has a tendency to come apart. Not a good sign.

There is a reason. Look at a Mueller clip and you will see the tabs connecting the 2 pieces are twisted, thus locking them in place.

The Mueller 27 will be my standard clip for as long as I can get it.

[KD5MDK]

I don't think so...the rule seems to be designed to ensure there's enough clip to grab on securely to the lame...the spring's behind the crossover, so you can't get the lame back there anyway.

Thanks. I had misunderstood what part they were measuring.

[Purple Fencer]

Thanks. I had misunderstood what part they were measuring.

No prob....like Donald always says, it's important to understand the rule, not just know it.

'Course, I'm still working on the understanding part at times.

[brtech]

Argh!!! 'Course, UNLIKE Uhlmann, I'm actually USING the screw the clip comes with, so the solder's a backup, NOT the primary connection.

Well, since the rule says it must be soldered, but does not specify that it has to be screwed, and experience suggests that the screw loosens way before a properly soldered joint gives up, I'd say the solder is the primary and the screw is a backup.

Just make sure you get a good solder joint (real solder flow on the clip). This takes patience and a BIG iron or gun. I don't even like using the 100 watt variety, I want 160 or 200 watts. Tin the end of the wire first. It helps to use extra flux. Most solder has flux in the core, but for a big piece like the clip, brush extra flux on the clip at the joint before you heat it up. Put the gun or iron on BOTH the clip and the wire. Wait until you can get the solder to melt on the clip. This is a lot longer than when you can melt it on the gun/iron tip or the wire. Feed enough solder to saturate the wire and then some more to get a good filet. The most common problem soldering is not enough heat. Just because you can melt the solder on the gun doesn't mean you get a good joint on the clip. The clip has to be hot enough to keep the solder molten long enough for it to flow.

The most common mistake I've seen other than not enough heat is allowing the wire to move when you remove the gun/iron. This is another good way to get a "cold solder joint". You really do need a good mechanical joint before you start soldering so the wire stays put when you remove the gun or let go of the wire. Using the screw can be helpful of course.

For some wire, it's better to solder first, and then crimp the barrel. The insulation can start to melt with the temp needed to get a good solder joint.

Make sure we can see the solder when you are done.

[KD5MDK]

Given how often masks are dangled by their cords, I suspect the screw offers a valuable strain relief on the wires, since it catches the insulation as well, while solder only holds the wire.

[N00bArmorer]

Thanks for the replys all.

Donald,

Can you you confirm what fencerbill posted about length checks for coiled mask cords?

[fencerbill]

I think brtech has not recognized that the real problem is the manufacturer's finish on the Mueller clips. You don't need a monstrous iron. A 40 watt iron or 80 watt pistol is fine.

brtech is just overcoming the finish with his huge tool and copious solder.

If you use enough flux and heat you will burn through the finish but mechanical preparation is easier.

Scraping, wire-brushing etc. works fine. Best is the disk like abrasive sponge from KMart auto section which fits on a drill press or hand drill(also great for cleaning rusty blades). The abrasive sponge disks for Dremels don't last very long.

There are some manufacturers that use Japanese alligator clips that are no trouble to solder with a small iron or gun.

Allstar/Uhlmann don't seem to use proper preparation. I have seen many brand new Foil body cords with a beautiful solder drop that was just sitting there with a cold solder connection.

In fact using a huge iron and too much solder is counterproductive. You don't want the solder to wick up the wire past the clamp. The wire will lose it's flexibility and break sooner.

Well, since the rule says it must be soldered, but does not specify that it has to be screwed, and experience suggests that the screw loosens way before a properly soldered joint gives up, I'd say the solder is the primary and the screw is a backup.

Just make sure you get a good solder joint (real solder flow on the clip). This takes patience and a BIG iron or gun. I don't even like using the 100 watt variety, I want 160 or 200 watts. Tin the end of the wire first. It helps to use extra flux. Most solder has flux in the core, but for a big piece like the clip, brush extra flux on the clip at the joint before you heat it up. Put the gun or iron on BOTH the clip and the wire. Wait until you can get the solder to melt on the clip. This is a lot longer than when you can melt it on the gun/iron tip or the wire. Feed enough solder to saturate the wire and then some more to get a good filet. The most common problem soldering is not enough heat. Just because you can melt the solder on the gun doesn't mean you get a good joint on the clip. The clip has to be hot enough to keep the solder molten long enough for it to flow.

The most common mistake I've seen other than not enough heat is allowing the wire to move when you remove the gun/iron. This is another good way to get a "cold solder joint". You really do need a good mechanical joint before you start soldering so the wire stays put when you remove the gun or let go of the wire. Using the screw can be helpful of course.

For some wire, it's better to solder first, and then crimp the barrel. The insulation can start to melt with the temp needed to get a good solder joint.

Make sure we can see the solder when you are done.

[Inquartata]

A manufacturer coating---no wonder I had so much trouble soldering the stupid things! And with a blowtorch at that!

[brtech]

Well, in all things, Your Mileage May Vary.

Generally, you use a 40-60w soldering iron for small tasks like solder lugs, lamp repair, hookup wire and things like that. You CAN use something that small, but you will wait a long time to heat up something as large as the clip. If you can get a good joint with a 40 watt soldering iron, great. I like my 200 watt Weller gun.

What I'm really puzzled about however, is what you are doing with the finish. As best I can tell, you are scraping off a zinc plate to get to bare steel. Are you using an acid flux? With rosin core flux, I think zinc plate is easier to solder to. It's got to be clean, and the clips often aren't.

[fencerbill]

Well, in all things, Your Mileage May Vary.

Generally, you use a 40-60w soldering iron for small tasks like solder lugs, lamp repair, hookup wire and things like that. You CAN use something that small, but you will wait a long time to heat up something as large as the clip. If you can get a good joint with a 40 watt soldering iron, great. I like my 200 watt Weller gun.

What I'm really puzzled about however, is what you are doing with the finish. As best I can tell, you are scraping off a zinc plate to get to bare steel. Are you using an acid flux? With rosin core flux, I think zinc plate is easier to solder to. It's got to be clean, and the clips often aren't.

I don't know what the coating is.

And brand new shiny Muellers fresh from the distributor are just as bad as old ones.

But if you scrape, or brush or almost anything, the solder sticks quickly and easily.

I use rosin core solder.

I tried using a propane torch once. All the solder just wicked up the wire.

[N00bArmorer]

I believe that the coating is zinc.

[Inquartata]

If so, heating it isn't good. While soldering for a few seconds isn't likely to be a big problem, zinc fumes are nasty, poisonous stuff and can make you quite sick. Possibly the manufacturer did not envision a use which involved having the clamps soldered...