Bottlehead Forum
Bottlehead Kits => Crack => Topic started by: jivex5k on August 12, 2020, 01:52:34 PM
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So I just got my crack kit today. I opened up the bubble-wrapped tubes to check them out, they look used.
They both have blemishes all over, the logos are rubbed partially off. Some parts of the glass are silver looking?
Is this just normal and I'm ignorant about the world of vacuum tubes?
I sent an email to queen@bottlehead, figured I would ask here too.
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Yes, we use old stock tubes and test them on a TV-10. To my knowledge, there are no new production 6080s. There are, however, tons of tubes that sat around in storage areas for decades that have a full service life ahead of them.
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Is there a way to clean them up?
Here's what they look like:
imgur.com/a/XaHoO7w
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Those don't look particularly dirty. You can clean the glass with Windex and a paper towel, but that may wipe the printing off.
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Okay thanks, I have no experience with this so I'll take your word. I'm really looking forward to building this thing, I put a cheap oscillscope together to pratice soldering beforehand.
Base is gluing overnight, and I'm researching finishes now. The miter joints were perfect.
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Yeah, the guy we use for the wood bases has to have some kind of magical miter saw, I can never get mine that perfect!
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Is there a way to clean them up?
Here's what they look like:
imgur.com/a/XaHoO7w
You are lucky you got a 12AU7 Baldwin black plate. Those sound really nice.
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The only cleaning you might want to do is use Deoxit contact cleaner on the pins using cotton swabs.
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A good old tube is better than a crappy new tube. A lot of tubes are sold as “new old stock†but many are really just lightly used and meet “as new†testing/requirements.
Mine came with a pretty well used looking tube. I was thinking I’d clean the glass and paint the metal sleeve with high temp paint. It’s not a special tube so I don’t care about the label. But then I got different tubes for better sound so that probably won’t happen :)
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the guy we use for the wood bases has to have some kind of magical miter saw
And he has about 20 years of experience milling them for us.
Regarding the tubes, yes they are used. As others have said, there really aren't any new 6080/6AS7s. Even the Russian ones are most likely rebranded old stock. We test each one before we send it out to be sure they meet specification. Cosmetically they may show their age. People used to give me shopping bags and cardboard boxes full of 6080s before we came out with the Crack. Now after so many years of selling thousands of Crack kits they are still readily available one or two at a time, but it is getting more and more difficult for us to acquire the large quantities we need to supply kits. I spend time each day competing (yup probably with you guys) for tubes on ebay. Secret stashes of several hundred new old stock tubes are long gone. We know because we bought 'em and shipped them out in kits.
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Sounds like it’s time for the Bottlehead DIY 6080 kit. It includes a blast furnace, some tungsten, and a heavy metal disposal bucket
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Thanks for the feedback, my concerns have been completely eased.
I've been taking my time finishing the base, used a chestnut stain and finished with odie's oil. It looks very nice, not too dark, not too glossy.
I used hammered on black spraypaint for the face plate and bell which also came out looking very nice.
I went to start putting the kit together and realized I spray painted the wrong side of the plate. Whoops!
It's all sanded off now, other side has been painted and is drying. I'm going to put another coat on today and then let it dry for a few more before working on it.
Maybe I'll build that power cable in the meantime...
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The hammer paint takes eons to cure, I would let it sit for at least two weeks before proceeding with the build.
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Will do, in no rush here.
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Watch out on recoat times for some spraypaints. I've had issues with recoating outside recommended times when using both Krylon and Rustoleum hammered finish (aka Hammerite) and not adhering strictly to the recoat times on the label instructions. I believe these have all been acrylic paints; some others, such as lacquers, may be more forgiving.
When following the label instructions, which were something like '...recoat within 15 minutes or after 10 days,' things went all right. The 15 minutes was good guidance, the 10 days was really more like two weeks or more, probably temperature/humidity dependent. Here in the northwest US, 15 minutes was really the only practical option as I never was able to outlast the longer recoat times. If one were to violate the recoat times, the paint tends to fisheye pretty consistently, usually necessitating sanding and starting over, but occasionally with kind of interesting results that are acceptable if not somewhat cool.
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Regarding sanding off the coat - if it's a recent spray job like this and hasn't fully polymerized I would be inclined to take it off with acetone rather than sanding. OK, I admit that I would probably just walk over the the panel stack, grab a fresh panel and start over. But you guys don't have that luxury. Use latex gloves (latex resists acetone, other glove materials like nitrile and poly don't), work outdoors with lots of ventilation and the other usual safety warnings.
Also, baking for 20 minutes at about 200 degrees will set Hammerite up pretty well. Don't go higher or longer as it may get brittle and tend to crack.
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It had dried for 24 hours. I just used a hand sander and 60 grit, it took a couple pads but it got the job done. Good to know for next time though, I'm completely new to woodworking and painting. I used Rustoleum Universal Hammered Spray instead of Hammerite, seems like I can bake it just the same from some research.
I got some antique looking jewelry box feet today, they look really nice with the chestnut finish.
I made sure they lifted the box as high as the rubber feet for ventilation, they lift it slightly higher.
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Got her finished today. I passed resistance checks, then blew the fuse. After going back over the steps I found the issue, had a rectifier in 22L instead of 21L, fixed that, cleaned up a couple of spots, new fuse. It passed voltage check perfectly and sounds great.
Thanks for all the help here! I'm sure I'll have more questions, I still need to install the upgrade but I'm going to sit with this for a little while first to get a better feeling of how it sounds.
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Looks like it turned out nicely.
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And he has about 20 years of experience milling them for us.
Regarding the tubes, yes they are used. As others have said, there really aren't any new 6080/6AS7s. Even the Russian ones are most likely rebranded old stock. We test each one before we send it out to be sure they meet specification. Cosmetically they may show their age. People used to give me shopping bags and cardboard boxes full of 6080s before we came out with the Crack. Now after so many years of selling thousands of Crack kits they are still readily available one or two at a time, but it is getting more and more difficult for us to acquire the large quantities we need to supply kits. I spend time each day competing (yup probably with you guys) for tubes on ebay. Secret stashes of several hundred new old stock tubes are long gone. We know because we bought 'em and shipped them out in kits.
Have you thought about Russian 6h13c tubes, there seems to be a plentiful supply of them from sellers in eastern Europe. I often see listings like this https://www.ebay.co.uk/itm/184166318354 (https://www.ebay.co.uk/itm/184166318354)
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I'm chillin on it for now. It sounds real nice, jamming to some stuff right now and the bass is hittin. After a while I'll upgrade with the speedball but for now whats the rush. haha
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Have you thought about Russian 6h13c tubes, there seems to be a plentiful supply of them from sellers in eastern Europe. I often see listings like this https://www.ebay.co.uk/itm/184166318354 (https://www.ebay.co.uk/itm/184166318354)
Yes, those are the Russian tube I mention as probably being old stock. That price is quite high for wholesale quantities. If we have to go to those the kit price will have to go up.