DB connectors

Another method of wiring connectors with lots of contacts is resistance soldering where a tweezer-type tool heats the connection with a very low voltage, moderately high current that passes thru the contact's solder cup, creating very localized heat.

The wire ends are stripped and tinned, and the solder cups at the ends of the contacts are tinned and partially filled with solder.

The tweezers are "pinched" onto the contact (each side of the solder cup), the resistance soldering station is energized (foot switch, typically), and the tinned wire end is pushed into the molten solder puddle in the cup as the heat increases to the flow temperature of the solder.

The current beiefly passes thru the contact, solder and wire end until the operator releases the foot switch, and then moves the tweezer tips to the next solder cup to repeat the process.

The tweezer tips only need to be kept clean (not tinned) so they can provide a good electrical connection with the contact or terminal to be soldered.

Te resistance soldering station provides a line/mains-isolated low voltage from a transformer that may have a variable duty cycle triac circuit, to adjust how fast the heat is generated in the contact. The variable duty cycle allows the operator to adjust/tune for different sized connections (very light duty for miniature contacts, or more sustained current cycles for heavy duty terminals).

Reply to
Wild_Bill
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Having soldered and crimped literally hundreds of DB-25s, I can say crimping is much faster, tool is much more expensive, though. If you're going to use this stuff on anything with a lot of vibration, go for the crimp. Eventually a soldered wire joint will fail just above where the pin is soldered on, given enough vibration. Found that out on the VW injection harness...

The pins are NOT Molex pins, you'll need either a different set of dies or a whole new crimper. Prices are all over the place depending on who's name is branded on its butt. Pins are pretty cheap, though. You'll want the special gizmo to remove pins, you WILL get one in the wrong hole eventually, trust me on this. Easier to swap crimped pins than to unsolder and resolder solder pot connectors.

Solder-pot connectors aren't that hard to do, it's just tedious work, tin wires, tin the pot, insert wire while heating pin, repeat ad nauseum. Helps to have the connector held in a vise, but I've done it hand-held.

If you really want to do a posh job, a short length of shrink tube right over the joints is the finishing touch. Gives a bit of strain relief and a bit of protection should something conductive make its way in.

Stan

Reply to
stans4

Crimpers for those things need to be high quality, and the decent ones cost $$$.

Reply to
Tim Wescott

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The worst were cables for old TV studio cameras with a lot of coax and different sized pins. It could take you days to do one plug. :(

RCA was bad enough, but I've heard that the Philips cables were so bad that guys would threaten to quit before they would repair one.

Reply to
Michael A. Terrell

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?PMPXNO=24730466?PARTPG=INLMK32 I get:

'The Enco Model Number that you entered could not be located.'

Reply to
Michael A. Terrell

Try searching for MSC 56451263:

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price,too.

jsw

Reply to
Jim Wilkins

That link worked.

Similar to the 4" one I use, and it cost me $7 new. :)

Reply to
Michael A. Terrell

I got mine for free. it was my first machine shop project in 1974 for my manufacturing engineer design and build class. We started by casting the AL frame. Our team must have spent 400 hours setting up and making a dozen. No such thing as an NC machine in that class. The whole point of the class was to set up small scale manufacturing.

That class is when my love affair with metal mangling, and the machines that do it, began.

karl

Karl

Reply to
Karl Townsend

Excellent price. I paid $30 for a 3" sine from 800watt on eBay a few years ago.

-- Experience is a good teacher, but she send in terrific bills. -- Minna Thomas Antrim

Reply to
Larry Jaques

I guess I'll find out. I plan to crimp them with whatever I can come up with and then solder before inserting. Total cost was under $20 so I'm not out much if it don't work. Plan "B" would be to hire the job out and get the solder type.

Karl

Reply to
Karl Townsend

400 hours over 12 units isn't really free. ;)

I had mine and was using it in under an hour. :)

Reply to
Michael A. Terrell

The pins have a round barrel into which you insert the wire. The crimper pushes four hardened pins into the barrel, dimpling it and pressing it onto the wire. Tres fancy. Because the barrel of the pin extends down into the hole in the housing you can't just crimp it by crushing it -- you have to do something that'll make it grip the wire without deforming it to the point where it won't go into its hole.

(I think the barrel is relieved where the crimper dimples it, so any little 'outies' don't interfere with putting it into the housing).

How far out in the boonies are you? Any electronics place that deals with DB connectors has a chance at having the crimper; if there's a contract cable assembly guy near you he'd probably be happy to make them up.

Note: I'd solder them myself, but I solder all the time. If I had to hire it done I'd either make damn sure the guy understood crimped DB connections, or I'd hire a kid to do the soldering and I'd stand over him for the first few connectors to make sure they were right. If I made more than 10 cables a year I'd probably buy a crimper -- but I make less than 1, on average.

Reply to
Tim Wescott

Thanks for the info. i can duplicate that easily. I'll drill a hole in scrap stock to hold the pin. Then a cross hole to hold a center punch. Put wire and pin in there and give it a slight whack for an indent. Then solder it.

karl

Reply to
Karl Townsend

So it seems simple - two 25pin D's and one 37 pin D. Another option is all in one socket.

Molex is another option. Round Cannon is another option.

D's require a D shaped hole while cannon are screw on and are round holes. Molex is typically square.

Consider the holes you have to mount them into. Each end could be different - matching the machine to machine.

Mart> I need to make up connectors like you see on the back of a computer.

Reply to
Martin Eastburn

Crimp requires an expensive (normally) crimp tool.

Mart> >

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Reply to
Martin Eastburn

The typical sub-D contacts that I'm familiar with use a different crimper than described, Tim.

Typical contacts for commercial grade sub-D connectors are similar to Molex contacts, but much smaller.. but they also have two sets of tabs that form U shapes, one where the stripped wire gets crimped, and the second set for gripping the wire's insulation.

The cross-section of the crimp area for the wire looks like the tabs rolled in to form someting like a 3 with a radius at the opening of the 3. The better quality crimpers will be compound-action types with ratcheting mechanisms to insure a full cycle, and numerous brands are good ones.. AMP, Black Box, Sargent, etc (all made in U.S.A.).

A simple scissor-type crimp tool will likely produce inconsistent crimps.. some may be OK, others may separate from the wire or be loosely crimped to the wire strands.

The crimper you described is generally for (fully round) machined contacts with heavier wall thicknesses, as used in high reliability avionics-type or aircraft circular connectors, but also used in higher quality sub-D connectors. Those crimpers sorta resemble a Buchanan splice crimper with an extension tube protruding from one side (Daniels tool, etc). The higher quality contacts are much better quality that typical commercial grade contacts which are stamped and formed from thin sheet brass.

You're definitely correct about not crushing the crimp areas with an incorrect tool, as the widening of the contact will interfere with proper installation, and the contacts are supposed to somewhat float in the connector bodies, but have good alignment.

For myself, soldering pre-assembled connectors is quicker than crimping, and a proper soldering job should be more reliable than crimping for someone that doesn't have some crimping experience, and definitely more reliable than trying to improvise a good crimp without the proper crimp tool.

Reply to
Wild_Bill

O.K. Because that one is designed for mounting directly to a printed circuit board. Not the one you need.

AMP makes nice ones for individual wire crimp terminals, but the size of the crimp is different from the Molex crimpers which I have seen. There are very good crimpers from AMP for the purpose (go to eBay for reasonable prices, or be sitting down for the new prices), and cheap ones also from AMP which are not as good. (The good ones crimp double flag pins -- one for the wire and another for supporting the insulation. The cheap crimper crimps one set of flags at a time, and you then have to flip it over to crimp the other half.

If you're really intrested in the good crimpers -- ask and I'll look up the number on mine. It has a nest to hold the pin in the right position for the crimping as well.

Tycho is the current name for AMP connectors.

Or -- if you want to do ribbon cable crimping, there are good terminals for those as well -- and they crimp all wires at once, but require yet another crimping tool -- or a bit of shop work to make your own supports to crimp in a vise.

Here is an example (25 pin):

I'm not at all sure about a 26-pin three row. (Unless you are talking about the connector used for VGA monitor connections?) Those use smaller pins, and I don't think that there are ribbon cable connectors for those -- the pin spacing does not work out right.

The three-row ones which I am familiar with are the DD-50 ones, normal sized pins, three rows, and they are made in ribbon-cable crimp style.

Here is the digikey search for the D-series ribbon cable ones.

You'll have to find another vendor than Digi-Key for the T&B Ansley connectors which I prefer for ribbon cable connectors.

Hmm ... looks like they are out of business. However, here is a substitute -- which DigiKey apparently carries (message dates from

2003, so the catalog and page number are probably wrong.

====================================================================== Unless you can find some new old stock you may be out of luck.

CW Industries makes the IDCs in the same style but are darker blue than T&B Ansley.

See:

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DigiKey lists them in catalog B022 on page 18. ======================================================================

Some possibilities above -- depending on which style of crimp you need.

Good Luck, DoN.

Reply to
DoN. Nichols

[ ... ]

NO!

1) Note that he said *four* hardened pins -- pushing equally from four sides at 90 degree intervals, so the pin stays centered.

If you do it with a center punch, things will be deformed in such a way that they won't go into the hole in the connector body well.

2) The same with solder. (Aside from not having access for the solder to the actual joint which is buried down in the tube, not out where you can get to it.)

And the solder will bulge out as well, to make it not fit well in the connector body hole.

*And* -- you won't be able to extract pins which wind up in the wrong hole when (not if) you get one wrong. (You do need the insertion/extraction tool to go with the pins.)

There are two styles of pins to consider.

A) The round machined pins which he described, which require a *very* expensive crimper, a special bushing nest for each size and gender of pin, and the machined pins are quite expensive too.

B) The ones with flag crimps. I've described this style before.

The crimper for these is still expensive -- but less so, and a lot easier to find on eBay at an affordable price. (The other still leaves you with having to find the right bushing nests for your pins.

The flag crimp pins are significantly less expensive (but not aerospace grade).

An example of the first style of crimper is the Daniels:

Auction # 230b3500c4 -- I think.

Note that the first row of pictures is the proper style of crimper, though no idea whether the bushing nest in there is right.

The "doorknob" sticking out of the side is the bushing nest.

Some of the photos in the second row are for a larger style, designed for larger pins, with a bushing which changes between sizes (but none of them tht you need). No certainty which he is really selling. :-(

And *this* one looks like the one for the flag type terminals for the D series connectors (of which DB-25 is one size). It has two crimp dies, and two support holes for two different gauges of wire. (One crimp terminal is marked with a blue dot, the other with a red dot.

Auction # 230527025153 for sure.

If you really care -- ask me, and I'll verify whether this is the right model by comparing it to what I have (after I dig them up). (90312-1).

Good luck, DoN.

Reply to
DoN. Nichols

...

DAMN! Auction closed before I read your post. Yes, I'll buy the right tool. Would you help me find one on eBay, please.

I bought from mouser, part 09 56 200 5601 as one example.

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also 15 pin and 25 pin. Looks like they have a good selection and cheap pricing.

DoN, Thanks for your offer to help, ahead of time. You are certainly the crimper expert on RCM.

Karl

Reply to
Karl Townsend

DoN, I've only got four pins to connect so the ribbon option is out. This is a one time job so I don't want to spend a fortune. I'd like to buy the tool on eBay, if you wouldn't mind pointing out the correct tool.

See my other response to your other post.

Karl

Reply to
Karl Townsend

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