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Re: Chassis and Panels for 18W Projects
Posted: Tue 11/24/20 3:18 pm
by coolidgeamps
I thought about going with press fit nuts vs the square/spring capture nuts used by Marshall but then thought I'm solving a problem that doesn't exist. And if ever there's a problem with the nut just pop a new one in and its good to go. The more I thought about going fancy with a press fit nut, the more it seemed like I was looking for trouble for no good reason.
Other general thoughts in no particular order,
1. Many shops wouldn't even give me the courtesy of responding to my RFQ. A simple no thanks would have been nice. It's not easy to find a job to take a smaller job like this.
2. The shop that made the first batch of 9 chassis did an 'okay' job. Prototek produced sharper/nicer bends. The first shop rushed the welding and it showed. I had to do a LOT more deburring on the batch from the first shop. I don't know if Prototek punched the chassis or laser cut it but far softer burrs and less of them.
3. If you have to have these shipped to you Prototek's packing was first class also. Each nicely wrapped in 1/8 inch foam like a Christmas present. Shipping 3,000 miles to my house on the west coast was, gulp, $175 for 2 large boxes.
4. On my next order I may have them cut out some socket hole covers for use when I'm building a 50 watt vs a 100 watt. Maybe some stiffening plates which I would add with these big transformers if shipping them freight to someone. Not really needed on amps for my own personal use. I would add an "L" shaped bracket for the voltage regulator, what a puny bend if you look at them leads they have. Definitely would rethink mounting for that next go around.
What would be ideal is if Mercury Magnetics would give me the bolt hole pattern for a number of common transformers and chokes so I could have a more universal chassis made. For laydown transformers I could have left some tabs for the big square opening holding it in place for use with stand up transformers. Just cut the tabs to remove the square for laydown.
Re: Chassis and Panels for 18W Projects
Posted: Tue 11/24/20 3:56 pm
by JMPGuitars
coolidgeamps wrote: ↑Tue 11/24/20 3:18 pm
I thought about going with press fit nuts vs the square/spring capture nuts used by Marshall but then thought I'm solving a problem that doesn't exist. And if ever there's a problem with the nut just pop a new one in and its good to go. The more I thought about going fancy with a press fit nut, the more it seemed like I was looking for trouble for no good reason.
Other general thoughts in no particular order,
1. Many shops wouldn't even give me the courtesy of responding to my RFQ. A simple no thanks would have been nice. It's not easy to find a job to take a smaller job like this.
2. The shop that made the first batch of 9 chassis did an 'okay' job. Prototek produced sharper/nicer bends. The first shop rushed the welding and it showed. I had to do a LOT more deburring on the batch from the first shop. I don't know if Prototek punched the chassis or laser cut it but far softer burrs and less of them.
3. If you have to have these shipped to you Prototek's packing was first class also. Each nicely wrapped in 1/8 inch foam like a Christmas present. Shipping 3,000 miles to my house on the west coast was, gulp, $175 for 2 large boxes.
4. On my next order I may have them cut out some socket hole covers for use when I'm building a 50 watt vs a 100 watt. Maybe some stiffening plates which I would add with these big transformers if shipping them freight to someone. Not really needed on amps for my own personal use. I would add an "L" shaped bracket for the voltage regulator, what a puny bend if you look at them leads they have. Definitely would rethink mounting for that next go around.
What would be ideal is if Mercury Magnetics would give me the bolt hole pattern for a number of common transformers and chokes so I could have a more universal chassis made. For laydown transformers I could have left some tabs for the big square opening holding it in place for use with stand up transformers. Just cut the tabs to remove the square for laydown.
I hear ALL of that. I've dealt with a lot of that with manufacturers also. Sometimes I've received replies saying they'll get back to me eventually, and of course they don't. What's the point of having an RFP/RFQ form if you're not going to respond?
I do like the idea of the cage nuts. I was thinking more about the lip going outward, but it would be fine like yours too. The cage nuts are great for exactly what you said; I had to drill out a rivet nut on a previous build because the nut was bad. Thankfully I have plenty of locking nuts in my stock stuff.
Dude, you gotta try the no clean solder I was telling you about...I'll send you some if you want.
You can still clean and do all that fun OCD stuff, but it's so much simpler without the fluxy mess.
Re: Chassis and Panels for 18W Projects
Posted: Tue 11/24/20 4:56 pm
by coolidgeamps
JMPGuitars wrote: ↑Tue 11/24/20 3:56 pm
Dude, you gotta try the no clean solder I was telling you about.
What's the brand and part # I'll order some and give it a try.
Re: Chassis and Panels for 18W Projects
Posted: Tue 11/24/20 5:34 pm
by JMPGuitars
coolidgeamps wrote: ↑Tue 11/24/20 4:56 pm
JMPGuitars wrote: ↑Tue 11/24/20 3:56 pm
Dude, you gotta try the no clean solder I was telling you about.
What's the brand and part # I'll order some and give it a try.
Kester 24-6337-8800
I usually get it on Amazon for about $25 or so a roll. I have more expensive solders including 4% silver solder, and I prefer that no clean stuff above them all.
Thanks,
Josh
Re: Chassis and Panels for 18W Projects
Posted: Tue 11/24/20 10:42 pm
by coolidgeamps
JMPGuitars wrote: ↑Tue 11/24/20 5:34 pm
coolidgeamps wrote: ↑Tue 11/24/20 4:56 pm
JMPGuitars wrote: ↑Tue 11/24/20 3:56 pm
Dude, you gotta try the no clean solder I was telling you about.
What's the brand and part # I'll order some and give it a try.
Kester 24-6337-8800
I usually get it on Amazon for about $25 or so a roll. I have more expensive solders including 4% silver solder, and I prefer that no clean stuff above them all.
Thanks,
Josh
Thanks I added a pound to my Digikey order. I wonder what happened to the whole lead free craze, Digikey has 2,214 of these in stock
On a related OCD note I want to try soldering in an argon inert gas at some point. I admit I'm jealous of big manufactures who do this and their solder joints look like chrome.
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 12:10 am
by JMPGuitars
coolidgeamps wrote: ↑Tue 11/24/20 10:42 pm
Thanks I added a pound to my Digikey order. I wonder what happened to the whole lead free craze, Digikey has 2,214 of these in stock
On a related OCD note I want to try soldering in an argon inert gas at some point. I admit I'm jealous of big manufactures who do this and their solder joints look like chrome.
That would be kind of amazing. Have I mentioned I love your OCD?
I think there are issues with reliability with the regular lead free solder. Or something like that. I would guess it was more prone to cold solder joints given the need for higher heat. Silver solder is often lead free, and it's a lot better than regular lead free, but still not as good as the 63/37 stuff. 63/37 being a eutectic alloy supposedly has a lower probability of cold solder joints.
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 2:54 am
by crgfrench
JMPGuitars wrote: ↑Wed 11/25/20 12:10 am
63/37 being a eutectic alloy supposedly has a lower probability of cold solder joints.
Check out
https://www.technic.com/sites/default/f ... rature.pdf
See how 60%Sn + 40%Pb changes state from solid to liquid over a range of 8 degrees C, from 183C to 190C? When your joint is cooling from 190 down to 183 the joint will be is a "semi-solid" state; not quite liquid and not quite solid -- more like peanut butter. This is a non-eutectic alloy, and if the joint moves during this period it can result in a cold solder joint. Now look at the next row down -- 63/37. This alloy solidifies at exactly 183C. It is eutectic, and there is no semi-solid danger period for the joint. That is the reason for the lower probability. Personally I use 60/40 because I like to watch that process, but you're definitely safer with 63/37.
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 1:49 pm
by coolidgeamps
JMPGuitars wrote: ↑Wed 11/25/20 12:10 am
coolidgeamps wrote: ↑Tue 11/24/20 10:42 pm
Thanks I added a pound to my Digikey order. I wonder what happened to the whole lead free craze, Digikey has 2,214 of these in stock
On a related OCD note I want to try soldering in an argon inert gas at some point. I admit I'm jealous of big manufactures who do this and their solder joints look like chrome.
That would be kind of amazing. Have I mentioned I love your OCD?
I think there are issues with reliability with the regular lead free solder. Or something like that. I would guess it was more prone to cold solder joints given the need for higher heat. Silver solder is often lead free, and it's a lot better than regular lead free, but still not as good as the 63/37 stuff. 63/37 being a eutectic alloy supposedly has a lower probability of cold solder joints.
The problem with the lead free solder is it solidifies to a frost appearance in oxygen, same as a cold solder joint you can't tell the difference. I chucked my spool of lead free solder in the trash after one amp.
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 2:09 pm
by crgfrench
coolidgeamps wrote: ↑Tue 11/24/20 10:42 pm
I want to try soldering in an argon inert gas at some point. I admit I'm jealous of big manufactures who do this and their solder joints look like chrome.
Love this idea! Maybe I will take a crack at modifying a TIG torch to fasten the collet around a Hakko FX600 instead of a tungsten electrode. Will post something if I do...
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 2:29 pm
by Bieworm
crgfrench wrote: ↑Wed 11/25/20 2:09 pm
coolidgeamps wrote: ↑Tue 11/24/20 10:42 pm
I want to try soldering in an argon inert gas at some point. I admit I'm jealous of big manufactures who do this and their solder joints look like chrome.
Love this idea! Maybe I will take a crack at modifying a TIG torch to fasten the collet around a Hakko FX600 instead of a tungsten electrode. Will post something if I do...
... and then the chassis disappears in the shell. How we all love those kinds of secrets
If we were still in the 80's we'd build plexi's with plexi
Re: Chassis and Panels for 18W Projects
Posted: Wed 11/25/20 9:30 pm
by coolidgeamps
JMPGuitars wrote: ↑Wed 11/25/20 12:10 am
Have I mentioned I love your OCD?
A little OCD is good when building amps. I didn't give it much thought until others posted pics of Cateory 10 OCD builds and made my work look like a crayon drawing. That just wasn't going to fly. lol
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 8:11 am
by JMPGuitars
coolidgeamps wrote: ↑Wed 11/25/20 9:30 pm
JMPGuitars wrote: ↑Wed 11/25/20 12:10 am
Have I mentioned I love your OCD?
A little OCD is good when building amps. I didn't give it much thought until others posted pics of Cateory 10 OCD builds and made my work look like a crayon drawing. That just wasn't going to fly. lol
LMAO! I can't even imagine. You're what, category 8.5? Hahaha
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 11:19 am
by coolidgeamps
JMPGuitars wrote: ↑Thu 11/26/20 8:11 am
coolidgeamps wrote: ↑Wed 11/25/20 9:30 pm
JMPGuitars wrote: ↑Wed 11/25/20 12:10 am
Have I mentioned I love your OCD?
A little OCD is good when building amps. I didn't give it much thought until others posted pics of Cateory 10 OCD builds and made my work look like a crayon drawing. That just wasn't going to fly. lol
LMAO! I can't even imagine. You're what, category 8.5? Hahaha
Okay it's possible I may need an intervention.
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 11:50 am
by JMPGuitars
coolidgeamps wrote: ↑Thu 11/26/20 11:19 am
Okay it's possible I may need an intervention.
That might be an understatement.
What wattage are those resistors??
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 1:27 pm
by coolidgeamps
JMPGuitars wrote: ↑Thu 11/26/20 11:50 am
What wattage are those resistors??
Only 1 watt Takmen Rey metal film, they have about a 5 watt sized lead. lol
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 2:48 pm
by JMPGuitars
coolidgeamps wrote: ↑Thu 11/26/20 1:27 pm
JMPGuitars wrote: ↑Thu 11/26/20 11:50 am
What wattage are those resistors??
Only 1 watt Takmen Rey metal film, they have about a 5 watt sized lead. lol
They really do! That's crazy. I mostly use CMF60 resistors now (1W, 500V). I'd try those Takmen resistors out because the leads look awesome, but man, I love having the resistance value written on the casing for the resistor. I test everything before I build, but it's nice to test everything all at once and leave it in a pile.
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 4:49 pm
by coolidgeamps
JMPGuitars wrote: ↑Thu 11/26/20 2:48 pm
They really do! That's crazy. I mostly use CMF60 resistors now (1W, 500V). I'd try those Takmen resistors out because the leads look awesome, but man, I love having the resistance value written on the casing for the resistor. I test everything before I build, but it's nice to test everything all at once and leave it in a pile.
Ditto. I have bins of the red PRP audio resistors and like how the print the value vs color stripes. Other than being drop dead gorgeous I'm not seeing an advantage to the Takmen's vs the PRP's. I'll probably use up what I ordered then go back. I test every component before it goes into the amp pots and all. Shockingly, after untold numbers of PRP's tested I found one that was mis-printed. Labeled 100k it was actually 47k.
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 5:26 pm
by JMPGuitars
coolidgeamps wrote: ↑Thu 11/26/20 4:49 pm
Ditto. I have bins of the red PRP audio resistors and like how the print the value vs color stripes. Other than being drop dead gorgeous I'm not seeing an advantage to the Takmen's vs the PRP's. I'll probably use up what I ordered then go back. I test every component before it goes into the amp pots and all. Shockingly, after untold numbers of PRP's tested I found one that was mis-printed. Labeled 100k it was actually 47k.
I almost never find anything even slightly off, but TBH it's nice when you find that 1 wrong value so you don't feel like you're wasting your time.
I've never tried the red PRP resistors. They don't seem that easy to get compared to the CMF stuff.
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 8:53 pm
by coolidgeamps
JMPGuitars wrote: ↑Thu 11/26/20 5:26 pm
coolidgeamps wrote: ↑Thu 11/26/20 4:49 pm
Ditto. I have bins of the red PRP audio resistors and like how the print the value vs color stripes. Other than being drop dead gorgeous I'm not seeing an advantage to the Takmen's vs the PRP's. I'll probably use up what I ordered then go back. I test every component before it goes into the amp pots and all. Shockingly, after untold numbers of PRP's tested I found one that was mis-printed. Labeled 100k it was actually 47k.
I almost never find anything even slightly off, but TBH it's nice when you find that 1 wrong value so you don't feel like you're wasting your time.
I've never tried the red PRP resistors. They don't seem that easy to get compared to the CMF stuff.
Sonic Craft carries them in 1/4, 1/2, and 1 watt. Wow they have gone up in price, they used to be 55 cents now 92 cents vs $1.50 for the Takman Rey's.
http://www.soniccraft.com/index.php/prp-watt-c-29_90_91
Re: Chassis and Panels for 18W Projects
Posted: Thu 11/26/20 9:17 pm
by JMPGuitars
That's not too bad. Some of the CMF I get are more expensive...and of course some are 1/3 the price too.
LOL! They offer matching. HiFi people are funny.
