++++++++++++++++++++++ See Also Gary Surrency's Build Tips ++++++++++++++++++ Date: Fri, 14 Dec 2001 14:59:23 -0700 From: Gary L Surrency Subject: [Elecraft] PTTL still way too common Hi all, (begin PTTL rant) This is an alert to those of you who are starting out building your new kits. The intent is to prevent problems before they arise and require a lot of troubleshooting later. I am once again seeing way too many kits that have the dreaded PTTL! PTTL stands for Poorly Tinned Toroid Leads, and it is still the #1 cause of all kit failures I see here on the service bench. Poor soldering is a close second, with improper parts placement coming in third. Please DO NOT begin or continue to build your kit until you have mastered the correct way to strip and tin the leads of the toroids!!! If you fail to do this, you will be causing yourself (and probably me) a lot of problems and time correcting PTTL later. Also be sure to wind the cores in the correct direction to match up with the PCB layout, and count the turns correctly. Each time the wire goes through the core, it counts as ONE turn. ......... etc ........... See Gary S's Build Tips for full text +++++++++++++++++ Date: Fri, 14 Dec 2001 23:53:45 -0600 From: "Andy Anderson W5VCJ" Subject: Re: [Elecraft] PTTL still way too common -- snip -- During construction of my K1, I quickly learned that the 1/8" rule was probably the only instruction in the book NOT to follow to the letter. I test mount each wound toroid and transformer before I even strip the leads, then I mark each lead with an extra fine felt-tip permanent marker on the component side so that I know how far up the lead I must tin. This is a quick and certain method for assuring that they leads are tinned far enough up, but not so far as to cause any shorts. Then, as Gary suggests, I start the tinning near enough to the mark to include it in the tinning process. I also have another trick I find helpful for transformers: Since the tinning will remove marks, and if one is a bit color deficient, I cut the leads to slightly different lengths with say the shortest as lead "1" (or "A"), a bit longer for "2", etc. and I write in on the diagram as I do it. This ensures I don't get the leads mixed up if I get interrupted, or just go brain dead. 73, Andy W5VCJ +++++++++++++++++ Date: Fri, 14 Dec 2001 22:48:23 -0500 From: "Tom" Subject: [Elecraft] Pre-Wound Pre-Tinned Toroids Hi Gang, Frank Kamp, K5DKZ gets my vote for "Man of the Year"! It's time to offer, *As An Option*, pre-wound/pre-tinned toroids. As an otherwise happy K2 owner I started on this list about 18 months ago and this is one of topics which keeps re-surfacing. I've read all about blobs, mini-solder pots made of spent gunshot shells, sand paper and Bic lighters. I still can't get a good looking toroid. Quite frankly, I'm ready for the ATU and I'm more than a bit intimidated by the prospect of going through that whole thing 10 or 12 more times. From a business perspective I think it would help sales to those of us who are less brave-hearted, or just down right tinning impaired, if we had the option available to us. Offering the toroids as an *option* would allow the purists amongst us the ability to roll their own. How about it guys, OHR used to offer pre-wounds and I think it was a real selling point for the faint of heart. I don't want to speak for the rest of the list, but I'd be willing to spend a few extra bucks to avoid that headache. As a matter of fact, if priced within reason, I'd be willing to buy a set for my K2 right now and pull all the toroids I've installed, that tells you how much lack of confidence I have in my tinning ability! Just my 2 cents. Tom McCulloch WB2QDG K2 s/n 1103 (with lousy toroids) PS - I'm not related to K5DKZ nor have I received any financial remuneration for my endorsement - But that's only because it hasn't been offered. t +++++++++++++++++ Date: Fri, 14 Dec 2001 21:15:32 -0800 From: Wayne Burdick Subject: Re: [Elecraft] "PTTL" and pre-wound toroids Tom wrote: > > Wayne, > Have you considered outsourcing? I'm sure this is a great "cottage > industry" for some of the guys on this list to consider. Thanks for the suggestion, Tom. If anyone is interested in going into business hand-winding toroids, please contact me. Otherwise, we're looking at industry winding houses which have large minimum runs--that's been the major stumbling block. Wayne +++++++++++++++++ Date: Fri, 14 Dec 2001 23:11:08 -0800 From: "John Grebenkemper, KI6WX" Subject: Re: [Elecraft] Pre-Wound Pre-Tinned Toroids I have found that the blob of solder on the tip of a hot soldering iron works great for some enamel wire, and works terrible on a different batch of enamel wire. It seems that some enamel insulation is much easier to melt, and is very easy to tin. Other batches, including some I have received from Elecraft, were much harder to melt the insulation. Is Elecraft always using low temperature enamel wire? Amidon Associates, http://www.amidoncorp.com/prices/tapeswires.asp, sells enamel wire that is supposed to melt at lower temperatures. The batches I have purchased from them work very well with the hot solder iron method. - -John KI6WX ++++++++++++++++++ Date: Sat, 15 Dec 2001 09:27:11 -0000 From: "Paul Barlow" Subject: [Elecraft] RE: PTTL Hello Elecrafters, this is a non-orthodox tinning toroid statement. I was initiated into the great mysteries of toroid winding when I built a Sierra and a few band cards, if you think the K2 has a lot of toroids, well build a Sierra and see! I use a crochet hook to pull the wire through, it makes for nice tight toroids and the wire doesn't kink. I don't know wht a crochet hook is in American if it isn't a crochet hook). I always scrape the insulatin off the wire with a sharp knife, with the wire flat on my thumb; I've always had good toroids that way, or at least so far so good. It may be that my iron isn't hot enough to strip the enamel properly on teh wire supplied with the K2 (it's a very ordinary Antex brand 18W iron with a large thermal mass around teh element and a small chisel bit). I did try the prescribed method but it just took too long. The only PTTL propblem I had was when I tried this method as directed when building a WM20 (yes we have a kit building probelem here I know) which took a lot of head scratching from a better electronic technician than I am to sort out. This is just my 2p / £0.02 worth. I now wind toroids for pleasure, well not really, but I will rewind one if I don't think it'e neat enough. I alos believe that you do have to learn to wind them yourself, it is part of the fun, (if that's what you call it). 72/73 Paul M0CDP GQRP 10289 Fists 5579 K2 #2356 KNB2 KAF2 ++++++++++++++++ Date: Sat, 15 Dec 2001 09:26:43 -0700 From: "Steve Banks" Subject: RE: [Elecraft] "PTTL" and pre-wound toroids Wayne, et al- Personally, I found the toroid winding-tinning-mounting-testing process an enjoyable part of the K2 experience. Obviously, one must be careful and do a thorough job of getting the toroid leads all cleaned and tinned correctly, but that's what the K2 project is all about in my humble opinion. I'd prefer to continue "rolling my own" toroids, using the butane-lighter/light-sanding process to clean the leads followed by careful tinning. (It worked for me anyway.) The toroid illustrations in the K2 manual were also spot-on; I never encountered a single problem, save for one winding lead which I soldered into an adjacent (incorrect) "via" hole. That was easily fixed after discovering that the PRE function was inoperative. Steve Banks K0PQ K2 S/N 1599 - -----Original Message----- From: owner-elecraft at qth.net [mailto:owner-elecraft at qth.net]On Behalf Of Wayne Burdick Sent: Friday, December 14, 2001 18:47 PM To: Elecraft Cc: Gary Surrency; Eric Swartz Subject: [Elecraft] "PTTL" and pre-wound toroids [PTTL = poorly-trimmed toroid leads.] Once you've stripped one toroid's leads correctly, and had the satisfaction of seeing it practically glow with happy, unimpeded electron flow, you can strip them all this way. It's a skill to be learned, and we do the best we can to teach the builder how to do it in our manuals. Regarding pre-wound toroids: we may offer these some day. It's too expensive to fold into the cost of the kits, by a long shot, so we'd have to charge for it. And even that would only be possible if enough builders want them prewound. If you have an opinion on how much a pre-wound set of about 20 toroids would be worth to you (retail), we'd love to hear it. Thanks! Wayne N6KR ++++++++++++++ Date: Sat, 15 Dec 2001 09:40:50 -0800 From: lhlousek Subject: Re: [Elecraft] RE: PTTL I've never had much luck with the heat strip method. It generates a lot of smoke and leaves the toroid leads encrusted with dross. I found scraping and tinning to be quicker, neater, and more reliable. People have expressed concern about nicking the wire. With reasonable techique I believe it is pretty unlikely to nick the wire. I've done a bunch (many more than in my K1 and K2), checked a few under a microscope, and have had no nicking problems. I wonder if Gary has had to fix many customer boards that had problems due to nicked toroids wires. Lou W7DZN ++++++++++++++++ Date: Sat, 15 Dec 2001 10:47:12 -0800 From: Wayne Burdick Subject: Re: [Elecraft] Pre-Wound Pre-Tinned Toroids "David A. Belsley" wrote: > Yes, this is my experience too. Some enamel wire strips easily with heat, > other does not. The stuff I got with my K2 kit did not. All enamel wire supplied with the K2, K1, and all options is "thermaleze," which is heat-strippable. Most enamel wire is *not* -- we specifically supply enamel wire that is. If anyone ever finds enamel wire supplied with an Elecraft kit that is the wrong type -- not heat strippable -- they should contact support at elecraft.com immediately to obtain the right stuff. 73, Wayne N6KR ++++++++++++++++ Date: Sat, 15 Dec 2001 12:06:43 -0700 From: Gary L Surrency Subject: [Elecraft] Soldering pots I would highly recommend NOT attempting to build your own soldering pot. Think of the consequences of a large pot full of hot, molten solder spilling on you, your child, or your pet. For this reason, the commerical pots are made purposely heavy and wide so they are not easy to turn over. Also, aluminum is not a good choice for the molten solder container, since it has a fairly low melting point. Stainless steel (as mentioned below by Jochen) would be preferred. Both of the commercial pots I have (300w and 110w), use stainless steel containers. To strip toroid leads well, the pot needs to achieve at least 750º to 800º F (398ºC-426ºC). If it is less than that, it won't work very well. I would also recommend keeping the soldering pot placed well back on your bench or table, and the cord protected from getting snagged by your feet or something else. You just don't want to risk spilling all that hot solder. Be sure to hold the toroid securely when dipping its leads in the pot, so the entire toroid does not fall into the molten pool! The last thing you want to happen, is for your just-wound toroid to become completely submerged and tinned with solder! And it would be dangerous trying to retreive it from the bottom of the solder pot. So there are some hazards associated with using a solder pot. Maybe it's just easier to buy a good temp/controlled iron and then you only have a little bit of molten solder to burn you. =:-o These pots also take much longer to heat up and cool down, compared to a soldering iron. My Hakko 936 reaches 700º in about 25 seconds from turn-on. It cools off pretty quickly too. Gary Surrency AB7MY ++++++++++++++++