As you can see in the pic below, 2 bad things happened when I tried to remove the volume control leads.

1. One of the traces became separated from the board (see pic). The red arrow points to the end of the trace (some metal still there.

2. The pads came off all 6 holes (see pic).

Before I expend the energy to try to patch this back together, is this worth trying to save or is a new board in order?

If so, any suggestions regarding getting the trace re-attached to the board?  

Also, is it possible to prepare the pads?

I'm disappointed - maybe this board is now junk.

Thank you all for your feedback.

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@4krow - many thanks for all these questions, as they lead me to research my soldering techniques.  Now I am a little more informed.  Here are the answers to your questions.

Any comments regarding restoration of the 6 pads that are gone?

1. I may be using too much heat.  My iron was set to 775 deg.  I did some research and seems I should be using 600-650 deg for tin/lead solder.  
2. I’m using a 60 watt Weller soldering station.
3. I was using conical tip - after some research, I should probably be using a bevel tip for this board.
4. When pulling out the pot, I applied heat only.  My solder sucker broke last week and I didn’t think to use solder wick.
5. The trace in question makes several turns and goes all the way across the board, to the 1k resistor which is connected to the input tube so it's a difficult repair to say the least.

Thanks for your reply.  I'll take your comments on the soldering to heart.

Agree - tried to repair the traces but it's not feasible.  I can try the jumpers but I already decided to get a new board last night.  I found that both traces from volume to the RCA inputs were lifted. I was concerned running 2 wires all the way across the board, over the components and to the inputs would result in noise so I bailed for the easier solution.  I'll let you know how it goes.

When I get the new board, I will mount the POT to the board and move the standoffs close to the edge of the enclosure so I don't have to run wires from the board to the POT.  

A secondary reason for me to restart is I need to redo the enclosure - it has so many holes it looks like Swiss cheese It's the first time I build an amp with an enclosure and I'm still learning so I chalk up the cost as training cost.  I've learned a lot and am enjoying it.

Cheers

Bummer! If it’s not too late maybe just build a point to point amp and forget the board?  You’ve got all the components.
Though, you probably need a new volume pot if you got it that hot.

Play it as is and see what you think. It's fine that you have a new board coming. Also, if you decide to go the point to point way, you are going to have to buy what are called turret strips to connect the wires to. Mostly it will work, but you may have to lengthen leads and other stuff to get everything to reach. Just something to consider.
Let us know the outcome no matter which way it goes. I think that you have done the right thing for now. Who hasn't burned a trace or broken something or lost something? You wouldn't want to see my short comings in the shop, BUT I will gladly show off my successes!
And yes, I know what it is like to have a few too many holes in a chassis as well.

 I am going to jump in here to make an observation. It was common for me in the past, to have trouble soldering in a way that was decent. I couldn't figure out why. It was only after I got the 'right' soldering station (in this case an888 model, made by Hakko), that I was able to make something that was both visually acceptable and much less electrically suspicious. Then, the solder mattered greatly as well. I ended up using 'Wonder Solder', what a stupid name, and continue to use it to this day. Yes, I have tried several solders and only wish that they worked for me but the results are not good. Dull looking joints, lousy flow, and more kept me using my favorite. The correct heat is very important, as you have found out with the damaged traces.
Looking closely at some of the tube socket connections, I see that the solder hasn't flowed evenly. No this is probably not an electrical fault, but may become one if a tube is taken out of the socket and the solder almost invisibly cracks.
This sort of this is seen at various points in the build as you have tried to get a lot of heat to say a speaker binding post, it isn't easy. Some of the blame there can be put to the position of the wire between two nuts rather than wound tightly around the end of the post, where wire soldering normally takes place. Again, there just may not be the intended physical strength in that connection.
My rule of thumb for pretty much every connection is to have a good mechanical connection before the solder is applied, rather than counting on the solder to be the glue. Many times I see wire just layed across an intended joint with a swath of solder to do the rest. In those cases, you then are relying on the solder metal makeup itself (mostly lead) to make the electrical connection and not the copper conductor itself.
When I find a wire to be small sixed for a solder hole in the circuit board, I will bend the copper wire into a J shape and then 'fit' it into the hole holding itself by the edge contact with the trace itself.

These observations are mostly self learned lessons as I went along for years trying get things at least better. Of course this is not intended so much as a criticism as a guide to follow. The intent is to have less troubleshooting of your own work, let alone defective parts or not so instructions for the build, etc.

Glad to hear it has quieted down for you. I think the residual hum is probably either in the transformer or needing more capacitance than specified in the schematic. I’m still fighting the same thing and many others posting here have the same experience.
If you feel the need to keep noodling now that it’s done, there are several parts of the circuit you can direct-wire and skip the board. For example, wire the output transformers directly to the speaker jacks and Haden mod caps right to the tube sockets.
Cheers!

Thanks 4krow and Mannytheseacow for your input.  I have traced the noise to be a 120Hz signal that is 1/2 rectified (pls see pic).  

The scope pic was taken at the output of the anode of the 6N1P.  It appears on both pins 1 and 6 (red square on schematic pic), and it goes away when I turn down the volume.  

It does not appear at the gate or cathode or anywhere before the anode up to the input rca jacks.  It also does NOT appear on the other side of the 47K 1/2W resistors just above the Anodes.

It would seem the source is the input tube - or maybe someone has some further insights on this.  At this point, I'm just after root cause of the hum because I'm a stickler for this kind of stuff.  I'm happy with the sound of the amp.  



upload pics

Thanks 4krow as always for your comments.

I have noticed something - the longer the amp stays on, the hotter it gets.  While that's to be expected, one problem I see is that the power x-former also gets hot and distortion seems to creep in and the hum gets worse.

The enclosure gets very warm to the touch in the area in front of the output tubes - but interestingly, the output transformers do not get hot!

My temp workaround is to place a metal plate in between the power transformer and the tubes (see pic).  It only solves the problem about 80%

Frankly, I'd like to know how to dissipate the heat from the box into the ambient.  I thought about drilling some holes around the output tube that is closest to the Power Transformer but I'm open to ideas.  The workaround is ugly.  

Oh, I'm attaching a scope pic of the diode after rectification.  I believe you asked about this...

4krow, thanks for the tip.

I was only able to find one seller on ebay who is selling MPCF-9 Pearl tube cooler for my Svetlana SV 83 output tubes (EL 84 compatible). With shipping and taxes about $70 so I'm wondering if you can suggest an alternate source.

I was also thinking about trying a small battery operated fan. I found a usb-chargeable one for about $13 on eBay and I may try this forest, without the tube coolers.

Thank you for your support