Twist lock capacitor replacement

[Stankfut]

Just curious if the 50/50 uF F&T capacitors will fit the same chassis hole as the older aluminum can twist locks. I know that CE makes the twist lock type (but I can't find 50/50's) but they are waaaayy too expensive for me! I also thought about stuffing the old ones, but right now I'm thinking F&T is the way to go if I don't have to do major chassis modifications (I know that I'll have to drill a couple of holes to fit the clamp).


Thanks!

[Ed_Chambley]

Sure will, just make sure you are centered well.

As long as you are referring to the 1 3/8 ones.

[Stankfut]

Yep, that's what I'm looking at. Thanks!

[EL34]

Yeah, just use a F&T 50/50 and a clamp


I have both of them here
http://hoffmanamps.com/MyStore/catalog/parts4.htm

[Stankfut]

Doug, that's one reason why I ask. The other is that I can buy all the F&Ts I need for the price of ONE CE

[HotBluePlates]

The CE caps are mostly for restoring old radios/electronics when you need that exact part, and they make a lot of types that would seem odd in a guitar amp (because they're meant to go into a specific radio). They're expensive because they're relatively low-volume production with few/no competing options, and as a repairman you're likely to pass the bill on to the customer (and the cost of the cap will be swamped by the labor charge anyway).

[sluckey]

Will it fit? There's another consideration. Do you have a square cutout or a round cutout for the twist lock cap can? If you have a square cutout it may be a very close fit, requiring almost perfect alignment of the F&T.

I replaced some on a Hammond conversion project a while back. The square cutout simply did not provide enough clearance (if any) between chassis and the F&T lugs to make me feel comfortable. I ended up punching the square hole to a larger round hole.

My point is you may not know for sure until you remove the original and start installing the replacement. Here are a couple pics from my conversion...

[Stankfut]

Sluckey, it is a Hammond Organ chassis, good call. To be honest, I haven't pulled it apart yet, I'm just assessing the cost of fixing it. I'm actually wanting to keep it intact as much as possible. It's not a B3, but hey, I'm not an organist, and from what I understand, with a few mods it can do the tone wheel thing pretty nicely for what I would need it for, and I couldn't beat the price....free


My big concern now is the tone generator is not generating (doesn't turn). I can get it to start if I turn the shaft a few times by hand. It will run for a while then stop. Since this is a capacitor start motor (L100 series), would a bad start capacitor be the issue? There is no sound when the generator is turning (except an occasional slight "windy" noise"), but I am assuming all electrolytic caps need to be replaced. The previous owner said it worked a couple of years ago when her daughter moved out and stopped playing it, so I think there is hope for it.

[sluckey]

A bad start cap would keep the motor from turning. But it may just need lubrication. I'd try the oil first.

Sounds like you are restoring the organ rather than gutting it? What's the model number on the chassis that you want to replace the cap can?

[Stankfut]

I'm guessing the cans on all three chassis are due for replacement, they look original. The organ itself is L 102. The chassis numbers are: AO 42, AO 43  and AO 47. I still haven't cracked it open yet, its my project for the weekend.

[Willabe]

Listen, that AO-47 unit is what wrecks the tone of those Hammonds and need to be taken out as soon as possible!!!!!

You should send it to me and I'll get ride of it for you so your not tempted to put it back in.     

Here look at this;

http://home.comcast.net/~seluckey/amps/warbler/warbler.htm


               Brad     

[Stankfut]

Brad, I've seen Sluckey's warbler before, and I must confess.....I nearly had a moment of weakness!

[Willabe]

Brad, I've seen Sluckey's warbler before, and I must confess.....I nearly had a moment of weakness!

               

[Stankfut]

I finally got around to opening up my Hammond and took a few pics. It seems that I am not the first one inside her, she had a partial cap job at some point. My plan is to replace all the e-caps, even the new-ish ones. I don't see any visual signs of other problems, so hopefully the caps will get me some sound!

[Stankfut]

I'll admit that my experience with vintage stuff is somewhat limited. Most of what I've done so far are scratch builds or repairs to small point to point amps....I've never worked on an older amp with a circuit board. With that in mind, I noticed that when this amp was recapped, it looks like the tech cut the lead off the old part, made a loop in the lead and soldered the new cap to the old lead. Is this an acceptable practice? I can appreciate why he/she would do that, as this board looks like it would be a bear to desolder, but I want to make sure my work is right!   Any tips from the pros would be greatly appreciated!!!!!

[sluckey]

it looks like the tech cut the lead off the old part, made a loop in the lead and soldered the new cap to the old lead. Is this an acceptable practice?

That's a dodgy repair IMO. Just lazy! Those old Hammonds used a cone board. You need to get your soldering iron tip under the board to heat the cone. Then that cap lead will just slip right out. When you replace the cap you must get the iron tip on the cone again. When the solder melts, the cap lead will slide right back in. Clean up any solder blobs that may form on the bottom of the cone. You may need to feed some fresh solder into the cone.

[6G6]

I'm not an organ guy, either, but I believe you can use a few drops of sewing machine oil or 3-in-One oil to get the tonewheels moving.

[Stankfut]

Sluckey, Thanks for the info. I thought it was crap work, too, but I wasn't just going to come out and say it because I tend to have overly high standards. I've never seen a cone board before. Seems handy if you have a bunch of wires going to the same hole.


6G6, I tried sewing machine oil, no luck so far. This weekend I may flip up the TG and try to get some oil on the bearings themselves. I need to order some Hammond oil though....

[sluckey]

The cone terminals force all the component leads to fit tightly together, making a good mechanical connection even before soldering. It's a great time saver during manufacturing. Heck, just shove the component leads and wires in without worrying about how far they extend thru the bottom of the cone. When everything is shoved in, cut the excess leads with one snip and solder it up. But I'm not convinced it's a good choice from a technician standpoint.

I actually salvaged a cone board from a Hammond AO-43 to build an Ampeg J-12 in my radio carcass. I had to use an air compressor, along with my soldering iron, to blow all the solder out of the cones so they would operate like new ones. The cones are actually split into quarter segments to allow the cone to expand as you shove leads into it. What a mess! Glad my labor is cheap.