Hey, Gurus and Nerds! What soldering iron do you use?

[fini]

Craig,

Shannon suggested I send him the cans, so I did. I'm not trying to be cheap, just assumed he knew what he was doing. Shoot, two new cans, that's $70! I could buy a bottle of wine for that! So, you suggest the ones from uncle Ned?

Rick, I'm jealous of YOUR round tuit!

Erik, I got the Hakko here:

http://www.hmcelectronics.com/cgi-bin/scripts/product/0460-0004

[NOSValves]

Fini,

Nope I suggest you buy right from the source. You know you are now following someone blindly and there was a time where I got pretty darn upset because you were asking for my help and then you were double guessing me....... (just had to say something no big deal though)

But anyway I would suggest you buy right from AEC they are CE manufacturing. This is the cans I would use.

CAPACITOR, ELECTROLYTIC, 80/40/30/20 µF @ 525 VDC

C-EC80-40-30-20

Made in the USA, to Mallory's original specs, on Mallorys original machinery. 80 µF, 40 µf, 30 µF and 20 µF section, all rated at 525 VDC.
1-3/8" diameter x 3-1/2" tall
Made in the USA by CE Manufacturing

I would also buy 2 of these to mount under the chassis

CAPACITOR, ELECTROLYTIC, 50/50 µF @ 500 VDC, JJ ELECTRONIC

C-EC50-50-500

Same diameter as LCR. Great for use in Marshall amplifiers.
1-3/8" diameter. x 2" tall.
S-H122 is a good mounting clamp for this can.


I know Shannon says he has tested and beefing up the PS has no effect but we all know tests are not the absolute final word. They are however a great tuning device and road map to getting to your final destination. The Dynaco Stock PS is ridiculously anemic to feed your 40 watts per channel. I have a pair of Heathkit 40 watters here with 4- 300uF sections stacked in pairs and that was original (300uF total effective). Trust me all Dynaco amps were built to the cheapest possible standard and the true glory is the iron which isn't surprising since that is what Hafler's background was at the time Transformer design and development. The Dynaco craze was a fluke that side tracked his career IMHO. You bought a good soldering Iron now do the same darn amps right[] by the way I order an Iron from the same place so now I have like 6 of them LOL !!

[fini]

Thanks for that specific information, Craig. It really helps me to have specific parts pointed out, rather than general ideas. Regarding the "second guessing", I was asking your opinion, as I ask others here and in other places. Please don't be offended if I do not follow your advice verbatim. There are many pats one can take in this hobby, and different aesthetics. Personally, I find the "make the most out of as little as you can" aesthetic to be pretty cool. For example, Mike Stehr's Maggotbox bargain amp, juiced-up with scrounged parts, is incredible art. Conceptually, I find his approach more pleasing than, say, someone who amasses the most pristine McIntosh gear just because he can afford it. I competely understand your suggestions regarding the MK-IVs, though, and hold your opinion in high regard. Thanks again for the info.

[NOSValves]

Thanks for that specific information, Craig. It really helps me to have specific parts pointed out, rather than general ideas. Regarding the "second guessing", I was asking your opinion, as I ask others here and in other places. Please don't be offended if I do not follow your advice verbatim. There are many pats one can take in this hobby, and different aesthetics. Personally, I find the "make the most out of as little as you can" aesthetic to be pretty cool. For example, Mike Stehr's Maggotbox bargain amp, juiced-up with scrounged parts, is incredible art. Conceptually, I find his approach more pleasing than, say, someone who amasses the most pristine McIntosh gear just because he can afford it. I competely understand your suggestions regarding the MK-IVs, though, and hold your opinion in high regard. Thanks again for the info.

Fini,

Just admit it your a cheap a$$[]

[fini]

I thought I just did!

[NOSValves]

Glad you took that as intended! It was a joke.

[Erik Mandaville]

Fini:

The JJ Electronics filter caps from AES are very good -- as are the new the multi-section cans. The latter are just kind of expensive, but will maintain the vintage look if that's what you both need and/or want.

With all due respect to Craig, I have a different opinion on the reforming of your original capacitors. I also would not be comfortable describing Shannon's reforming them as a 'mistake.' This doesn't make me 'right' or 'wrong,' but I'm comfortable offering my opinion on what you're doing. My belief is that those capacitors are probably still fine. However, as you found yourself, there is nothing magical about desoldering. If when you get the capacitors back from Shannon you find they become leaky and ineffective (there are a number of symptoms to look and listen for), there are some things you can do to test (without test equipment) them. Actually, you'll need a multi-meter, so let me correct myself on that. IOWs, you don't need specialized test equipment, which I also don't have.

Like you, I like the idea of 'making do' the best one can with what we have -- within reason, meaning that 'what we have' is in proper working condition.

Please keep us up-to-date with how things are going with this!

Erik

[fini]

Well, FWIW, here's what Shannon wrote a few days ago:

"I've finished the first pass of reforming the caps, and I'll do a final check this weekend. They look very good. I've been reforming until they drop to 500uA leakage at 525V."

[3dzapper]

Dang I hate that! ? I lost my post.[]

fini, Wasn't one of the power trannies blown when you recieved those amps?

I would follow Craig's advice and replace all the components in the PS section. He is correct in his assesment of David Haffler and Dynaco. They built their kits at a price meant to maximize the sales of their excelent transformers. They were very successful at this. How Haffler did this was to use minimalist circuits which, surprisingly sounded better and provided more power than many of the higher priced products available at the time.

One thing Craig did not mention is the little choke under the chassis. Because of the blown tranny, i think it would be prudent to also replace those. They are available from Ned at Triode for about $10 each. Cheap insurance since you have no means to effectively test the original ones against shorted turns.

Enjoy your new iron!

Rick

[fini]

Yep, a power transformer WAS blown. As Craig has remembered, they had been converted to SS rectification. So, are we talking replacing parts (I'm all for that, there's not much in there), or changing the circuit? I feel confident I can follow the original instructions and schematic with new, even upgraded parts, but deviations from that make me a little nervous (unless, of course, clear instructions are available).

Yeah, I had already decided the chokes needed replacing (one of them appears to be oozing...).

[Deang]

Stay on course. It's important that you are comfortable with what you are doing. As you learn and grow in confidence -- you can try other things later.

[fini]

Good advice, Dean, but I have to understand which course (or coarse) to choose... ;^)

[Deang]

You choose the one that gets it working properly with the least amount of trouble. It's what I was trying to say in that other thread -- it's not just the soldering, but the digestion of a lot of information associated with the project. If you keep it simple, you can actually think about what you are doing and why. Later, you can move to more complex things, and if you are well grounded in the simple concepts -- you'll do better when you tackle them.

BTW, make a habit of heat sinking your parts when you solder.

[NOSValves]

Well, FWIW, here's what Shannon wrote a few days ago: "I've finished the first pass of reforming the caps, and I'll do a final check this weekend. They look very good. I've been reforming until they drop to 500uA leakage at 525V."

Fini,

The entire problem with reforming is that they ease the voltage into the cap and get this magical leakage number but in reality when the soft voltage advantage of reforming is gone the cap will indeed start suffering from the slam at turn on that it has been subject too under normal use and in your case abuse with those SS rectifiers that were used most likely in the amps since 1992. Been there done it a number of times and when request by my customers I STILL REFORM and yes they can live a very long happy life after reforming. I have some amps out there with original cans for 4 years still playing away. How ever in this case the cans have been abused. Heck a good percentage of cans that I have reformed have ended up back here sometime 2 months and sometime 2 years later to be replaced.

An electrolyte can not be accurately tested with a Multi meter no way no how. You can get a basic good/bad idea from a MM but nothing beyond that. The electrolyte has to be placed under full voltage condition too properly test it. This indeed takes specialized equipment of course I own this equipment to back up the advise I give unlike some others around here. I'm sure Shannon owns this equipment also.

I wouldn't take the chance in your case since your cans have indeed been abused. To me $70 just isn't worth it. Do what you please there your amps.

Craig

[NOSValves]

Fini:

The JJ Electronics filter caps from AES are very good -- as are the new the multi-section cans. The latter are just kind of expensive, but will maintain the vintage look if that's what you both need and/or want.

With all due respect to Craig, I have a different opinion on the reforming of your original capacitors. I also would not be comfortable describing Shannon's reforming them as a 'mistake.' This doesn't make me 'right' or 'wrong,' but I'm comfortable offering my opinion on what you're doing. My belief is that those capacitors are probably still fine. However, as you found yourself, there is nothing magical about desoldering. If when you get the capacitors back from Shannon you find they become leaky and ineffective (there are a number of symptoms to look and listen for), there are some things you can do to test (without test equipment) them. Actually, you'll need a multi-meter, so let me correct myself on that. IOWs, you don't need specialized test equipment, which I also don't have.

Like you, I like the idea of 'making do' the best one can with what we have -- within reason, meaning that 'what we have' is in proper working condition.

Please keep us up-to-date with how things are going with this!

Erik

Erik,

Check my C22 rebuild page on my website those cans were giving the big "Okay" by a reknowned technician just 1 short year ago. I don't know for sure but I bet he uses your method of testing also. I hate to say the obvious but your advising from the cheap seats once again.

Craig

[NOSValves]

Yep, a power transformer WAS blown. As Craig has remembered, they had been converted to SS rectification. So, are we talking replacing parts (I'm all for that, there's not much in there), or changing the circuit? I feel confident I can follow the original instructions and schematic with new, even upgraded parts, but deviations from that make me a little nervous (unless, of course, clear instructions are available). Yeah, I had already decided the chokes needed replacing (one of them appears to be oozing...).

Good decision and I'm glad Rick caught my brain fart.

Fini,

If giving you advise doesn't turn into a battle with the "Cheap Seat advisers" I will be more then happy to give it. But if I have to micro analyze every step I advise you then I will just simply bow out. Life is to short for that.

Craig

[Dflip]

Starting in January, Europe will require no lead soldering for all equipment sold there because the landfills will no longer take items with lead in them. I know that McIntosh is now using lead free solder which has a higher melting temperature. How will this effect the wattage of the soldering iron that someone might consider buying? I do realize that this has no effect on our vintage equipment, but given that this is where everyone will have to head, if they want to sell in the Europe, it is better to be safe than sorry. Most companies will follow this standard within the year because it is the strictest standard and therefore will become the norm.

Thanks in advance for your advice.

[djk]

Unless you are doing ball-grid arrays you don't need special stuff for SMD. The special stuff is for automated assembly lines (vapor phase, infra red, etc) with solder masks and pre-heat ovens.

Metcal is the best because of their patented design (Hakko is in court over this and has lost the first round).

The Metcal system has the lowest temperature and the highest wattage of anything, that's why it works so well (the exact opposite of what someone else claimed was best). Just make sure the tip matches the size of the work.

A Metcal depends upon low tip mass and instant response to load changes. They only draw a watt or two on most joints, until you hit a big lug, or a ground plane, then they will draw 40+ watts in an instant. This allows you to work quicker and do less damage to the parts and board. Tips will last years, unless you drop or scratch them.

If you work on expensive boards or use expensive parts, you cannot afford not to use a Metcal.

[NOSValves]

djk,

Very interesting and makes perfect sense. Thanks for the information. When you say that Hakko is in court does this mean they have been uses such technology in there products breaking some patient laws?

Craig

[Erik Mandaville]

Fini:

Please let us know how this comes along, ok? As I mentioned, if when you get the reformed cans back in the power supply you find they are not working properly, they can very easily be replaced. For now, I think this process is a great learning experience, and I think gave first-rate advice on keeping to a level of involvement you're comfortable with.

There are some specific things you can look and listen for regarding the performance and/or behavior of the capacitors, and you don't need specialized equipment in order to determine if it would be better to replace them. My feeling is that you can get some longer life out of them. If that turns out not to be the case, you yourself found how straightforward it is to desolder the connections and remove them.

Cheap Seats, himself!

Erik