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Qbus
July 16th, 2015, 09:53 AM
Why dose wire wrap tools and wire and stuff cost so much? Wanted to do a project using wire wrap but looking on eBay it appears that anything involved in wire wrap is a small fortune. Thought people would be selling that stuff cheap.

Chuck(G)
July 16th, 2015, 10:09 AM
Well, they were at one time. I think I paid about $10 for my G-D electric gun, complete with bit, used. I used to buy 32AWG Kynar wire by the thousand-foot spool for not much more than 22AWG hookup wire. What's gotten expensive are the posts and socket pins--the gold-bugs got 'em you know... Radio Shack used to (a couple of years back) sell a decent manual wire-wrap tool and stripper for about $7.

WW is durable and great for prototyping--make a design change just by unwrapping and re-doing. Not at all like PCB work--there, if you make a big mistake, it's re-do the PCB artwork--and if you're using SMT, pretty much throw the old one away and buy a new set of components.

mwillegal
July 16th, 2015, 12:30 PM
The ease of rework is about the only remaining motivation to stay with wire wrap.

I think wirewrap equipment business is becoming a very niche market. Certainly, you don't see it used for new professional production or prototype gear, anymore. Many hobbyist have gone away from wire-wrap, for a variety of reasons. It's not very suitable for surface mount components. PCBs are pretty easy to layout on modern PCs. If you do it at home, the cost of etching a PCB is amost nothing and results in a much slicker looking prototype. Professionally produced prototype PCBs are also very affordable.


regards,
Mike Willegal

Chuck(G)
July 16th, 2015, 12:50 PM
The ease of rework is about the only remaining motivation to stay with wire wrap.

I think wirewrap equipment business is becoming a very niche market. Certainly, you don't see it used for new professional production or prototype gear, anymore. Many hobbyist have gone away from wire-wrap, for a variety of reasons. It's not very suitable for surface mount components. PCBs are pretty easy to layout on modern PCs. If you do it at home, the cost of etching a PCB is amost nothing and results in a much slicker looking prototype. Professionally produced prototype PCBs are also very affordable.

To be frank, if you're using SMT and are using 200+ pin TQFPs, PCB is just about the only way to do something. And I don't think that you can successfully execute a homegrown PCB with that sort of precision (including vias), much less a multilayer board. Although, using PCBs as an intermediate stage (cf. Schmartboards) is another option.

In a sense, this is a shame, as it prompts the hobbyist to go with the "ready made" solutions, such as the Arduino boards, rather than work the design out himself.

lowen
July 16th, 2015, 01:22 PM
In a sense, this is a shame, as it prompts the hobbyist to go with the "ready made" solutions, such as the Arduino boards, rather than work the design out himself.

Things like the Papilio DUO might be more to your liking, with an ATMega32 plus some static RAM plus a Xilinx FPGA and software to 'breadboard' into the FPGA. This is what is being taught these days (where 'these days' is actually the last 15 years) for digital design. See http://www.gadgetfactory.net/papilio/

This place in the link is very much hobbyist in nature.

Chuck(G)
July 16th, 2015, 03:01 PM
I think the best deals are in the the adapter boards, such as these (http://www.ebay.com/itm/5-x-TQFP-100-TQFP100-Adapter-PCB-SMD-convert-Pitch-0-4mm-for-PIC24-PIC32-/321135003880?pt=LH_DefaultDomain_0&hash=item4ac52348e8). Mount a few SMT passives on the bottom and the MCU on top and you've got a high-performance MIPS-based 32-bit MCU to incorporate into a design that won't break the bank and still is amenable to prototyping without the expense of a custom PCB.. It even features a programming header that can supply power as well. I suspect that the ARM Cortex family has similar things available--and again, insanely cheap for the capability. I've used AVR-family MCUs, but I think they're pretty much behind the times in terms of capability--and probably not up there in the quarter-megabyte of SRAM category like the other MCUs-- (though I have designs that added external SRAM to the ATMega128 and 162 pretty easily--I don't know if any other more up-to-date members offer lots of fast SRAM).

KC9UDX
July 16th, 2015, 03:19 PM
To be frank, if you're using SMT and are using 200+ pin TQFPs, PCB is just about the only way to do something. And I don't think that you can successfully execute a homegrown PCB with that sort of precision (including vias), much less a multilayer board.

Precision, yes. Vias, yes, albeit larger. Multilayer, no, not practically.

glitch
July 17th, 2015, 06:01 AM
I think the best deals are in the the adapter boards, such as these (http://www.ebay.com/itm/5-x-TQFP-100-TQFP100-Adapter-PCB-SMD-convert-Pitch-0-4mm-for-PIC24-PIC32-/321135003880?pt=LH_DefaultDomain_0&hash=item4ac52348e8).

I keep a pile of those around for working with PIC microcontrollers that just aren't available in DIP or coarser pitch SMT. Solder some long square-pin headers to the breakout board and you can still wire-wrap! Plus the "socket" becomes really cheap.

Christoffer
August 4th, 2015, 02:57 AM
In a sense, this is a shame, as it prompts the hobbyist to go with the "ready made" solutions, such as the Arduino boards, rather than work the design out himself.

This is very true. Today the computer is usually lain out for you, and you only focus on the I/O of it.

I think wirewrap gear is so expensive because it is of insanely high quality. Wirewrap socket pins has to be machined or milled to get the sharp corners, and the pins are generally usually either gilded of silver plated. wirewrap wire is platinum coated, and the tools require very fine machining too, to avoid tiny deformities that'd cut the wire. You put a LOT more strain on the wire when you wrap than one should think, the connection is actually a cold weld.

And because it's niche, there's almost no market for "low end" wire-wrap gear (I've tried some; it's really really really crappy).

--Christoffer

roberttx
August 13th, 2015, 05:22 AM
Is there really still that much demand for wire wrap gear? I have a big box full of guns, tools, kynar wire, etc, somewhere. Maybe I should find it?

Chuck(G)
August 13th, 2015, 08:26 AM
Not a lot of demand, although a telephone euipment installer told me that you can still find the stuff in telephone COs (heavier wire though--maybe 26AWG). It's incredibly reliable if done right--probably more so than lead-free solder connections on a PCB (that's a guess).

Al Kossow
August 13th, 2015, 08:52 AM
the pins are generally usually either gilded of silver plated. wirewrap wire is platinum coated

reference?

silver plating would oxidize. I've never seen a wirewrap post that looked like that.
Gold, or tin plated machined pins, but not silver.

I have seen silver plated WW wire though, and it does oxidize.

Like Chuck said, the careful shopper in decades past could pick up thousands of ft of #30 in the surplus places in the valley.
I still have a couple of rolls.

The gold bugs buy up all the WW stuff that shows up on eBay.

You could buy non-machined wire-wrap sockets, but they were junk. I have a Nuclear Data ND-812 that was made with those (Cambion)
on one huge wire-wrap board, and the sockets have all rotted.

toober
August 15th, 2015, 07:10 AM
I have seen silver plated WW wire though, and it does oxidize.

Like Chuck said, the careful shopper in decades past could pick up thousands of ft of #30 in the surplus places in the valley.
I still have a couple of rolls.


Quite a lot of wirewrap wire is silver plated. The recyclers generally do not want it because the silver is considered a contaminant when it gets to the mill. A few recyclers will take it if they deal with a precious metal refinery - but still, not worth much.

I think I have seen a few silver plated wirewrap sockets, but they certainly are not common.

--
Will