Weller PU-1D / TCP-1 / PT-H6 parts info

Can't recall the numbers but you'll probably need a new element as well as barrel. They changed (increased) the outside diameter of the replacement TCP elements around 2003, and consequently also the inside diameter of the barrels. Maybe the old element would work in a new barrel but I wouldn't be surprised if the thread or something else doesn't fit properly.

I had the opposite problem, the element burned out so I needed to replace the barrel too. I'd consider sending you my old barrel, but I am too far away (Australia) (and I can't guarantee that I would be able to find it).

I pretty much only use two sorts, I think they are PTDD7 and PTAA7 but not sure any more as I mostly use a Metcal these days.

No, 6 is too cold even with tin-lead. You want a number 7, and I think that will do nicely for lead free as well. Number 8 will burn tracks off the board unless you are very careful and quick.

Not easy to find with google. It doesn't help that Farnell uses the wrong photo for most of the tips.

Hmm, ok, this is just the sort of thing I needed to know, thanks.

Just OOI, I have these measurements of my existing barrel:

Well, that's a very kind offer and it's the thought that counts Chris. ;-)

Erm, I don't know if mine has aged hotter or somesuch but just yesterday (and with the tip falling out) I easily soldered some mains cable to some solid metal terminals (inside an IEC plug) with the .8mm tip with no real issues?

I'm not sure I'll be actively using any lead free but may well come across it etc.

Not good.

Great! (not). ;-)

Cheers, T i m

p.s. A mate has a nearly unused soldering / rework station spare that he said he will give me first refusal on, as / when he finds it! It has a hot air gun, temp controlled soldering iron and smoke extraction. I think it was bought locally and they also stock the spares etc but I have a small electric hot air gun for heat shrink and don't solder enough to bother too much about the fumes (along with not breathing when soldering etc ). The problem is it's a bit big so sot something I could just pop down on the kitchen worktop to do a quick soldering job? ;-(

Cheers, T i m

I just got a reply from an eBay seller who has measured the barrel they are selling and their measurements are at the end of mine in square brackets:

8.6 mm outside diameter of tube. [9.2] (This could be the larger diameter to take the larger filament you mentioned Chris?)

12 mm across the flats of the nut. [12mm] (Ok, so that hasn't changed.)

So, I could get this one and then it would take the newer filament later if required?

Cheers, T i m

Ok I dug out my box of weller parts and I did find the old barrel. (I expect that it would cost a bit to post though as it won't fit in a letter. Let me know if you are seriously interested.)

I also found the old-style dead element and some new-style elements and barrels. The new-style barrel does go onto the old-style element, but even with the thread tightened all the way, it does not grip the soldering bit tightly so it wobbles and probably doesn't conduct heat all that well. I'd say it is not usable like that.

PT-DD7 part number 0054127799, (Farnell 416-435, their picture is wrong) and PT-P7 (part number 0054134799)

MX-500 actually, even worse!

Well, I have some 6 and 7 and 8, and I prefer the 7.

I guess I've been lucky till now. ;-)

Ok, thanks again and let me see what I can do this end before I waste your time and effort etc.

Ah.

Checking the existing tip in my original element (without the barrel) it seems to fit it reasonably well but with a bit of slack. Fitting my barrel doesn't help as the tip just falls through it. ;-(

Thanks for those Chris.

Noted and I've ordered a couple of 7's.

Cheers, T i m

Hmm, my replacement barrel arrived today (next day, thanks Rapid Electronics Ltd ) and if screwed on finger tight, the tip seems to be pretty solid, so I wonder if there is still more to it (like the tip dimensions)?

The other question is do we generally put any sort of thermal / anti seize paste on these things please, or would pretty well anything simply burn off?

Cheers, T i m

Hello,

Just so you know, the tip number indicates temperature in Fahrenheit.

If we're talking magnastats here, never throw away a bit without removing the magnastat, quite easy to swage-fit to another bit of right form but wrong temp.

Hi Tim, ;-)

Ah, so I'm guessing Weller is American? It's funny, whilst I was born into a mostly imperial measurement world and was then merged into metric, one of the few things I don't ever think I ever used is Fahrenheit scale (maybe early tropical fish stuff)? I guess that's because it's scale doesn't relate to anything tangible to me, like the freezing and boiling points of water etc?

ah, 6=315, 7=370 and 8=425 DegC (although I agree those numbers don't have such a ring to them and would be difficult to mark on a tip). ;-)

There seem to be a few places in the UK as well Tim.

Yes, and we also have eBay etc where the odd good thing comes up. ;-)

I've just fired my iron up with the new barrel and tinned the ends of a couple of bits of stranded copper cable with my 6 tip and it seemed to do so very easily. Maybe a 7 would be required if using unleaded solder (which I'm not)?

I have a couple of 7's on their way so I can see how they compare on my iron.

Cheers, T i m

I think we are (if that's what the Weller Curie Point temperature switch system is called). [1]

Ah, and that explains the 'waisting' I saw on my existing (and only) tip. Good tip. ;-)

Cheers, T i m

Also check that the element switches off with no tip in it. The mechanical switch that is operated by the magnet can get stuck/seized, meaning that the iron gets much hotter than it should regardless of which tip is in it. It's entirely possible that a properly working iron with a number 6 tip is hot enough for what you are doing, but if you find that it is too hot then perhaps the switch is stuck.

Chris

Ok, that's good. Maybe they made more different sorts than the ones that I have. I'm pleased that it worked. I'm curious whether your new barrel is larger in diameter than your old one.

I guess you could use copper grease or aluminium grease and though the grease part would probably burn out and smell and make a mess, the metal particles ought to remain. I doubt it is necessary and I've never used anything like that on a soldering iron. The only ones that I have had get really stuck were Antex ones. I think that if you just disassemble it occasionally either to change tips or just to inspect it, that should prevent it getting seized up (and if it does you would catch it before it is impossible to remove).

Me too. ;-)

Yes, it is.

Then that is probably my answer Chris. ;-)

Understood.

Thanks again, cheers, T i m

I'm ahead of you there. When I was still at BT (so 40 yeas ago now!) I modded my PU-1D base with a front mounted red LED that goes on when the element is on (and it's still working). ;-)

So, if it was stuck on (or off) I'd soon see it in the 'activity' LED (and have in the past when a small tap on the element seems to cure it, typically stuck off).

Your good point is noted though. ;-)

Cheers, T i m

p.s. JOOI ... I've just timed the iron heating from cold (20 DegC ambient) to the 600 DegF (315 C) tipped iron heating till the LED goes off and it was 55 seconds.

Ok, thanks. That confirms that it is a new-style barrel. I guess there are more types of element and barrel than I know about.

I'm glad to hear you got it working though I don't think I was much help.

While at it , if your one is like mine and lacks an indication , other than slight clicks, that the magnastat is functioning. With a selected collection of zeners and diodes it is possible to put a droppered LED, across the AC supply line. Unfortunately LED off when iron is on (supply loaded), but at least , it shows the switch is not stuck on.

Sometimes just having someone to open up new trains of thought or considering new / other possibilities are all it takes Chris. ;-)

Cheers, T i m

That's how it was designed but I was reminded when talking to Chris that I modified mine 40 years ago with a red LED in the front that comes on when the element is drawing current.

Ah, my LED definitely comes on when the heated element comes on but I can't remember how I got there?

I do know I built, assembled and fitted it and it could have been co-designed by one of my co-workers at BT at the time.

Cheers, T i m

Oh well, I was hoping to find out how you did it. I can think of a few ways but none of them are very elegant.