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    New Kit Purchase

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    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    New Kit Purchase

    Post by WntrMute2 on Sun Jan 02, 2011 6:20 pm

    For the first of the year, I ordered a ST-120 kit to build. This will be my first kit. I'm a bit nervous so chime in with tips and suggestions. I bought a Weller digital soldering station, a couple of extra tips, and a few tools, wire strippers, cutters, helping hands to round out my tool selection. I have a lighted magnifier as well as some of those cool looking magnifying goggles. bounce Woo-ho.
    Dave

    Bob Latino
    Admin

    Posts : 2377
    Join date : 2008-11-26
    Location : Massachusetts

    Re: New Kit Purchase

    Post by Bob Latino on Sun Jan 02, 2011 6:32 pm

    Hi Dave,

    The best advice is ...

    1. To proceed slowly and double check every step. So what if it takes a little longer ... You chances of success are better ...

    2. Don't try to do too much in one day. After 4 or 5 hours either take a break or stop altogether for that day. Some people are in such a rush to get it done they work late into the night when their mind is getting "foggy". This is prime time to make a mistake.

    3. If you haven't soldered in years or never soldered before PRACTICE on some wires or some old computer or other piece of electrical gear (old radio, old stereo etc.). Below is a link to some hints on good soldering techniques ..

    A soldering tutorial

    Bob

    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: New Kit Purchase

    Post by mantha3 on Sun Jan 02, 2011 9:49 pm

    Nice Amp! I built my ST-120 in Nov. The thrill of hearing this work after the build is worth the price alone. The sound is awsome and mine keeps sounding better and better.

    Listen to Bob on points 1 and 2. Go slow. I pushed a 9 hour day on this build and I caught a mistake... You just start to get dumb after too long.

    Get a room or nice quiet place where you can dedicate to the build. A place where you can start this... Get to a point where you call it a day and can walk away and not worry about kids/cats etc messing around. Get a nice old kitchen table or something big to spread out on. Get some good light to work under. 4' flour. garage light is what I used.

    I used 62/32/2 Silver Bearing Solder .015 (thin) on the VTA build. Remember to get thin diameter solder for the VTA in particular. Made it a bit easer for me anyway. I then had some standard 60/40 solder for the rest of the build (wire etc) I got the solder that is coiled in tubes. You can drill a hole in the end of the tube and run the solder out the tube... Hold it like a pencil.

    One weekend you sand the paint the transformers... Maybe that same weekend you build the VTA board.

    The amp should then take a couple days... Do a step. Review what you did and dbl check the step.. Then put a check mark next to the step.

    Some time before the build (night before) take an hour or so to read the manual steps.. When you kind of run in your head the steps it helps then next day when you do it for real..

    I had never built anything like this. Just go slow as Bob said. Re-read the step and check the work.

    OH, If you got the amp and did not get the cap upgrade or the Russian PIOs then get em now!!!! For what ya spent thus far the savings on the caps is not worth it. Go that extra mile on the $$.

    Get some needle nose pliers, Some De-Soldering Braid for any possible error.

    PS - This is all just random thoughts.. You have what you need.

    Go slow and don't let the excitement of hearing the amp make you rush things.

    Take some photos along the way. Looking back on the build process as you listen to the amps is cool and makes ya proud.

    Good call on building this yourself. Easy to just spend extra on having Bob do the build but doing this yourself is something you will appreciate down the road. You get a lot of insight into these things by building them yourself.

    mantha3

    Posts : 298
    Join date : 2010-11-10

    Re: New Kit Purchase

    Post by mantha3 on Sun Jan 02, 2011 9:51 pm

    Oh,

    Go to www.youtube.com and search for "How to Solder" or "How to Solder circut boards" etc. Much good "how to" stuff on youtube... Worth an hour or so for some soldering

    wolverine

    Posts : 60
    Join date : 2010-02-20

    Re: New Kit Purchase

    Post by wolverine on Mon Jan 03, 2011 1:43 pm

    When soldering....I always have a toothpick ready and just put a very small dab of flux on bare metal. I know you're probably using resin solder, but I just find it much easier myself soldering to bare metal if I just put a small dab of flux on the metal first. When I am doing a restore of an old amp I will clean metal tabs off using sand paper, or a tiny wire brush, first myself. The cleaner the metal the easier and quicker the solder flows onto it. Kind of a pain in the backside sometimes LOL, but it does make my soldering to old metals a whole lot easier. Poor solder connections are really a lot harder to trace down once you get deep into a build or restore. Verifying each connection looks good as you go is really a whole lot better. I find it really helpful myself to solder nuts in place on things if possible. Put the screw through the hole, then tighten a nut down snug and solder it on around the outside edges of the nut. Best to do it this way so you know the screw will align well with the nut when you try to assemble.

    Oh yeah, and keep the tip clean also, and the screw tightened that holds the tip in, really helps to transfer the heat to the metal parts if you have a good clean tip. Those little sponges that come with many of the sets work really well if you just keep them moist and wipe the tip off on it after you solder.
    wolverine

    Luddite

    Posts : 235
    Join date : 2009-02-04
    Age : 66
    Location : Texas

    Re: New Kit Purchase

    Post by Luddite on Mon Jan 03, 2011 2:38 pm

    wolverine wrote:
    Oh yeah, and keep the tip clean also, and the screw tightened that holds the tip in, really helps to transfer the heat to the metal parts if you have a good clean tip. Those little sponges that come with many of the sets work really well if you just keep them moist and wipe the tip off on it after you solder.
    wolverine

    Although it may not be absolutely necessary, I always wet my cleaning sponge with distilled water. That should lessen the possibility of mineral deposits on the tip. Apparently, this has worked well over the years, as my soldering tips have always remained clean and shiny.

    Charlie

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Mon Jan 03, 2011 7:44 pm

    Thanks guys! Shipped today.

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Thu Jan 06, 2011 8:58 am

    Any other suggestions as to solder types, brands, thicknesses? I forgot to order some and am looking at the selection at RS. Is that good enough or should I wait and order some. Also, do you guys prep the new circuit board or anything before starting? I saw a tutorial that scrubbed the board with a scotchbrite pad and alcohol. Any value to that process. Bob, your service has been great, ordered my amp on Sunday and received it on Wednesday!!

    Bob Latino
    Admin

    Posts : 2377
    Join date : 2008-11-26
    Location : Massachusetts

    Re: New Kit Purchase

    Post by Bob Latino on Thu Jan 06, 2011 9:08 am

    Hi,

    Don't touch the board with ScotchBrite or anything else. It is unnecessary.

    As to solder diameter - Any rosin core solder can be used. .032" to .050" diameter is probably the best thickness that will work on both the driver board and on chassis solder connections. The Radio Shack solder at the link below is fine to use ..

    Radio Shack .032" solder

    Bob

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Fri Jan 07, 2011 7:29 pm

    I'm planning on painting those transformers tomorrow but I don't understand the directions completly (not a confidence building start). Why 6 bolts? if there are 3 transformers with 4 bolts each, shouldn't I be buying 12 bolts? Also, if I take out the nylon spacers to paint, will the plate alignment be maintained? I now that the number of bolts seems petty, bu I am trying to understand each step as I go along.
    Thanks, Dave

    Bob Latino
    Admin

    Posts : 2377
    Join date : 2008-11-26
    Location : Massachusetts

    Re: New Kit Purchase

    Post by Bob Latino on Fri Jan 07, 2011 8:38 pm

    WntrMute2 wrote:I'm planning on painting those transformers tomorrow but I don't understand the directions completly (not a confidence building start). Why 6 bolts? if there are 3 transformers with 4 bolts each, shouldn't I be buying 12 bolts? Also, if I take out the nylon spacers to paint, will the plate alignment be maintained? I now that the number of bolts seems petty, bu I am trying to understand each step as I go along.
    Thanks, Dave

    Hi Dave,

    All you need are 6 bolts because all you have to do is use TWO BOLTS per transformer on opposite diagonal corners of each transformer to hold the two covers on. The plates are lacquered together and will not come apart when you take off the transformer bolts. Only the two transformer outer "bell" covers will become loose until you tighten your six "painting bolts". Yes - remove the nylon shoulder washers when you paint.

    Bob

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Mon Jan 10, 2011 5:30 am

    Got my VTA board built, had trouble on only one or two joints. Seemed I couldn't get the solder to flow onto the PCB twice. Ended up OK but required a little more time on the trace than I was happy with. I needed to refer to some pictures on the web a few times and Bob himself once. A clear photo of the top and bottom would have helped. Hint, hint. Once mine is working properly, I'll see about posting my VTA photos here if it is OK with Bob.

    Bob Latino
    Admin

    Posts : 2377
    Join date : 2008-11-26
    Location : Massachusetts

    Re: New Kit Purchase

    Post by Bob Latino on Mon Jan 10, 2011 7:10 am

    Hi,

    If you have trouble making the solder flow into a joint, there is a possiblity that your soldering pencil is not getting hot enough. This is more likely to happen on soldering in the capacitors rather than the resistors since the capacitor leads have more mass. More mass requires more heat from the soldering pencil. When you get to the chassis connections you will find that the internal connections to the speaker binding posts require the most heat.

    Bob

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Sun Jan 23, 2011 8:48 am

    Smoke test right now!!

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Sun Jan 23, 2011 12:18 pm

    Works! Can't really tell about the sound as of yet. But it is alive!

    Bugs

    Posts : 91
    Join date : 2009-04-17

    Re: New Kit Purchase

    Post by Bugs on Sun Jan 23, 2011 3:29 pm

    Congratulations!!!

    I'm sure you did a fine job and will enjoy the amp for a long time to come.

    Best

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: New Kit Purchase

    Post by WntrMute2 on Mon Jan 24, 2011 2:52 pm

    Had a minor setback due to poor soldering of 1 connection. Fixed and back playing tunes. Just finished "Dirty Side Down" by Widespread Panic. Sounded fantastic!

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