DE-SOLDERING CYRUS II / REPAINT - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 9th December 2012, 07:42 AM   #1
ftpols is offline ftpols  Japan
diyAudio Member
 
Join Date: Dec 2012
Location: Yokohama, Japan
Cool DE-SOLDERING CYRUS II / REPAINT

I bought a Cyrus II in Japan in 1989 and it it is the best amp I ever owned except for a Luxkit A3000 power amp which I built. Age is telling and some of the caps are failing and, unbelievably, the body paint is melting... Regrettably, Cyrus no longer has a a distributor/service agent in Japan. There obviously are a lot of experts using this site, so I would be very grateful for their kind help in repairing my Cyrus II as follows: 1. I can't de-solder the caps. The solder is as hard as steel. I tried a 30W soldering iron and, recklessly, a 150W soldering iron. No dice. 2. After repairing the sound, I need to repaint the body. I need primer and paint that won't degrade because of the Cyrus II mag/aluminum cast body. I am thinking about using an epoxy-based paint for durability. Any ideas, please, about stripping the original paint without scratching the metal, about the best primer and paint? Many thanks for any help. Ftpols
  Reply With Quote
Old 9th December 2012, 07:51 AM   #2
Mooly is offline Mooly  United Kingdom
diyAudio Moderator
 
Mooly's Avatar
 
Join Date: Sep 2007
The only thing I can think of with the solder is that the thermal capacity of the soldering iron bit is too low. Big caps with tags etc can soak up the heat. Apart from special high melting point solder (which is occasionally specified for parts that run extremely hot) I've never come across anything other than "normal" solder in all the 10's of thousands of commercial products I've worked on.

Maybe post a picture of the joints your trying to unsolder and your iron and tip ?

I'm no expert on paints but I believe for aluminium you need an "etching" primer.
__________________
-------------------------------------------------------
A simulation free zone. Design it, build it, test it.
  Reply With Quote
Old 9th December 2012, 07:57 AM   #3
diyAudio Member
 
zeonrider's Avatar
 
Join Date: Mar 2004
Location: Belgrade RS
Quote:
Originally Posted by ftpols View Post
Any ideas, please, about stripping the original paint without scratching the metal, about the best primer and paint? Many thanks for any help. Ftpols
Long ago I was doing the same.

1. Sandblasting
2. Powdercoating

Regards zeoN_Rider

Last edited by zeonrider; 9th December 2012 at 07:57 AM. Reason: fg
  Reply With Quote
Old 9th December 2012, 09:05 AM   #4
ftpols is offline ftpols  Japan
diyAudio Member
 
Join Date: Dec 2012
Location: Yokohama, Japan
Default DE-SOLDERING CYRUS II / REPAINT

Quote:
Originally Posted by zeonrider View Post
Long ago I was doing the same.

1. Sandblasting
2. Powdercoating

Regards zeoN_Rider
Many thanks, zeonrider. I agree with the sandblasting but have doubts regarding the Powdercoating, which was probably used for original manufacture. Many thanks, and all the best.
  Reply With Quote
Old 9th December 2012, 09:16 AM   #5
ftpols is offline ftpols  Japan
diyAudio Member
 
Join Date: Dec 2012
Location: Yokohama, Japan
Default DE-SOLDERING CYRUS II / REPAINT

Quote:
Originally Posted by Mooly View Post
The only thing I can think of with the solder is that the thermal capacity of the soldering iron bit is too low. Big caps with tags etc can soak up the heat. Apart from special high melting point solder (which is occasionally specified for parts that run extremely hot) I've never come across anything other than "normal" solder in all the 10's of thousands of commercial products I've worked on.

Maybe post a picture of the joints your trying to unsolder and your iron and tip ?

I'm no expert on paints but I believe for aluminium you need an "etching" primer.
Many thanks, Mooly. I am flumoxed because: 1. I replaced capacitors successfully in Sony VDRs, etc 2. Many other DIYAudio members have replaced Cyrus capacitors Anyway, I also asked Cyrus and am waiting for their reply. Many thanks for your help. Ftpols.
  Reply With Quote
Old 10th December 2012, 11:54 AM   #6
diyAudio Member
 
Join Date: Apr 2010
Location: Coffs Harbour, on the east coast
Apart from a smaller range of colours, powder coating can be much better (tougher) than sprayed enamel or epoxy based paint. Some enamels can be baked for a tougher finish but if you need to have someone do the painting for you, straightforward powdercoating should be cheaper too, as there are fewer operations. Automotive lacquers are also excellent but when used with all their recommended additives and primer, undercoats etc. the best types become quite expensive for a small job like an amplifier case .

Whatever coating type is used, an etch bath, wash or suitable etch primer for paints, as Mooly indicates, is essential with all bare metals. Powdercoaters don't always use proper surface etching or sandblasting processes and I think that's why many coated products have poor adhesion.
__________________
regards
  Reply With Quote
Old 11th December 2012, 01:35 PM   #7
ftpols is offline ftpols  Japan
diyAudio Member
 
Join Date: Dec 2012
Location: Yokohama, Japan
Smile DE-SOLDERING CYRUS II SERIES 07 / REPAINT

Quote:
Originally Posted by Ian Finch View Post
Apart from a smaller range of colours, powder coating can be much better (tougher) than sprayed enamel or epoxy based paint. Some enamels can be baked for a tougher finish but if you need to have someone do the painting for you, straightforward powdercoating should be cheaper too, as there are fewer operations. Automotive lacquers are also excellent but when used with all their recommended additives and primer, undercoats etc. the best types become quite expensive for a small job like an amplifier case .

Whatever coating type is used, an etch bath, wash or suitable etch primer for paints, as Mooly indicates, is essential with all bare metals. Powdercoaters don't always use proper surface etching or sandblasting processes and I think that's why many coated products have poor adhesion.
Many thanks for the technical advice, Ian. I am having second thoughts, though, because of the time required to replace the caps and I also have a faulty power switch in the PSX unit - it's a Heath-Robinson push-button job. Despite the very good circuit designs and great sound quality, I was disappointed by the Cyrus II / PSX construction. For example, the poor paint job, loose stand-offs installed in the PSX, a plastic cable for the main power cord fixed with useless sponge adhesive, a plastic heat-shield or emf barrier lying loose at the bottom of the case. Some of these things I can fix easily enough but I wonder if it's worth all the effort. I dread starting work on the amp itself - I still work and don't have much free time. I might bin the Cyrus and PSX and buy a Marantz PM7000, which at least has service facilities here in Japan. Enjoy Coffs Bay...
  Reply With Quote
Old 11th December 2012, 02:03 PM   #8
lohk is offline lohk  Europe
diyAudio Member
 
lohk's Avatar
 
Join Date: Apr 2001
Location: Northern Noricum, near the Limes
before you bin it please sent it to me :-)
- these items can be quite easily repaired and modified
__________________
/lohk/
  Reply With Quote
Old 18th December 2012, 01:39 PM   #9
ftpols is offline ftpols  Japan
diyAudio Member
 
Join Date: Dec 2012
Location: Yokohama, Japan
Default DE-SOLDERING CYRUS II / REPAINT

Quote:
Originally Posted by lohk View Post
before you bin it please sent it to me :-)
- these items can be quite easily repaired and modified
Hi, Lohk.

Many thanks for your encouragement. I fixed the PSX power switch (dislocated circular spring) and it works fine. I replaced two 470MF/50V capacitors in the PSX which were bulging. I also replaced two 470MF/6V BP capacitors and two bulging/leaking 470MF/50V capacitors in the Cyrus II. I used Nichicon MUSE ES for the original BPs and Nichicon MUSE FG or KZ for the others. Sound quality improved dramatically, so I decided to replace the remaining 20+ originals.
As mentioned earlier, there was a plastic shield lying loose in the PSX. It has a white strip on the long side. I thought the white strip was adhesive but it isn't tacky. I replaced it as shown but could you or someone kindly confirm the correct location and where the white strip faces toward; e.g. towards the toroid trans, etc. Many thanks.
Attached Images
File Type: jpg Cyrus PSX-1.jpg (141.9 KB, 52 views)
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Cyrus II r/ch distorcion astrostar Solid State 22 17th January 2014 06:17 PM
cyrus 2 repaint colour idea ?? homertooties Solid State 1 16th July 2012 07:05 AM
HELP, repaire Cyrus LFAU similar to Cyrus II ccheung Solid State 12 5th June 2012 09:12 AM
Mis-behaving Cyrus II gazbo83 Solid State 5 31st August 2009 06:28 AM
Trying to fix my Cyrus II amp karl.s. Solid State 9 18th September 2005 02:07 PM


New To Site? Need Help?

All times are GMT. The time now is 03:06 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2