I talking about maybe a 1 molar solution. Safe to handle.
Tex put all there aluminum chassis parts in vats of sodium hydroxide to strip off the oxides before screen printing and or clear coating. For anything that didn't matter the stuff was just hung to dry and left to re-oxidize. This got rid all the finger prints etc.
The NaOH was just an example of a common obtainable chem sold as lye for soap making.
Don't know if it will work.
Here is an example of one panel that sort of worked using isopropyl to remove the film. It didn't get all the film off.
I had to do a clear coat to hid the remaining film. Still looks a bit blemished though.
If I can get a process down that works flawlessly then I'll start a thread explaining how it's done. For everyone.
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That would be pretty much correct. As all I have is anecdotal evidence, I will not use terms that are specifically defined as I do not *know* if they are or are not the correct term to use. My point is to suggest that it is possible to compare, broadly, the two technologies and see what is truly different and that could be tested. Group Delay, overshoot, resonances ....
I am not as convinced that the transient response of even smaller diaphragm condensers is as "nice" as you feel. Still a lot of overshoot in the response. Agree wholeheartedly that manufactures are afraid to publish good specs for mics, David Joshephson had been working for years to try and get a minimal useful set of standards adopted by the AES for mic testing.
And all this is really only directed at a very small part of the industry as most of the product is done in such a way that it will make small difference as there is no reproduction of sound going on, it is production of a product creating a sound coming out of your speakers that is deemed music. That's not good or bad, just is.
Alan
Do you mean in the USA? I did not live here then, so can't say when it trended in the U.S. By the mid 80s it was in full swing in Europe. The Western Electric triodes were already legendary by 1983.
Glass Audio started in '89.
Follow the money. EU and JA DIY/ made hardly a blip on the dying world of tubes. In the late 80's tubes were next door to trash. Look at the prices of NOS tubes. They didn't start going up until the 90's.
A year or two after Nobu's SET 300b showed up in Glass Audio there were SET's all over the audiophile shows. This would be about '94.
Follow the money. EU and JA DIY/ made hardly a blip on the dying world of tubes. In the late 80's tubes were next door to trash. Look at the prices of NOS tubes. They didn't start going up until the 90's.
A year or two after Nobu's SET 300b showed up in Glass Audio there were SET's all over the audiophile shows. This would be about '94.
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NaOH would be far away from any choice Id' make. Dextrose should be water soluble (eventually). Is that not a possibility? If you need to accelerate the process, denatured alcohol and/or a small drop of soap would be a first choice. And let them soak for some time. Just do not scrub in the areas of the decals themselves, but you may around them (which would accelerate the breakup of the dextrose and provide weak-points in the dextrose film over the decals in which the water/EtOH might gain access.
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Well certainly in UK the tube revival was in full swing in the 80s when I lucked out on my Radford cheap. Now UK didn't have the huge supplies of nice NOS tubes you have in the states and event then, PM components were selling JAN for £££ and getting gold dragon tubes made in china. I must admit that I think the DHT craze passed us by for pre-amps but not for power tubes such as the 211.
When I was buying my first good stuff valves were always on show in dealers, both C-J and ARC as well as Beard, EAR, audio note, audio innovations, croft and a numerous others who have fallen by the way side. Many were a generic rehash, but some were most defiantly not. Back then I was so naive I thought nuvistors were a cool idea for an audio amp...
When I was buying my first good stuff valves were always on show in dealers, both C-J and ARC as well as Beard, EAR, audio note, audio innovations, croft and a numerous others who have fallen by the way side. Many were a generic rehash, but some were most defiantly not. Back then I was so naive I thought nuvistors were a cool idea for an audio amp...
True, true and true. Just bring back the k170 and j74 and life will be a dream.'these are the best times for audio'. We have tubes, vinyl is back, very good digital and solid state analog (discretes, opamps etc) has never better.
Tek used multicolor anodize for their panels. Those are not silk-screened. Its a great process but not for DIY. Really durable. They did that and PCB's in house.
For the truly adventurous Aluminum Anodizing at home - DIY aluminium Anodising Looking at the chemicals etc. I'll pass.
It is a water process. The film has been treated to resist water. Once baked it almost water proof. It's quite a bit different from what we used on model air plains and such.
It is developed for this purpose.
I'm sure if I soaked long enough in alcohol or as you suggest vinigar it would eventually come off. But this could take days or weeks vinegar. I'm looking for something that will increase
the rate of dissolution.
I thought perhaps SY might already know being a material scientist or others.
I test a sample with 1 molar NaOH. It does work but 1 molar seems to be to concentrated.
If the heat of reaction is too high the heat will melt the toner. I don't want to remove too much of the aluminum either. 0.2 molar is better but I'm still seeing steam.
I got that info from Dick Moore. Early in his career he worked for Tek on the assembly line.
I was just guessing with the silk screen. But now that you mentioned it, it doesn't look silk screened.
I'm reluctant on the NaOH since it has a good chance of undercutting the oxide layer under the toner, and having it flake.
Soap, EtOH, heat are all good, mild things to accelerate the dextrose removal. If you can, simply lightly scratching the surface of the dextrose film will accelerate the dissolution process greatly.
Soap, EtOH, heat are all good, mild things to accelerate the dextrose removal. If you can, simply lightly scratching the surface of the dextrose film will accelerate the dissolution process greatly.
Well, by the looks of it they're going for electrostatics (Al2O3 surface charge is positive, iirc and toner is definitely negative) and remelting for conformality. Which case the dextrose, also negatively charged is there as a vehicle.
But if the film is dense, then yeah, it's going to be hard to break through that crust.
I'm even reluctant to suggest ultrasonic agitation in the fear that the toner will dislodge.
But if the film is dense, then yeah, it's going to be hard to break through that crust.
I'm even reluctant to suggest ultrasonic agitation in the fear that the toner will dislodge.
NaOH used to be easily available. It is now no longer sold retail in the US as it is used to make methamphetamines. I use it all the time to clean aluminum before painting. The special paints will adhere to aluminum but not to the oxide.
So I would clean the panel with a mild solution of that or a strong dish washing detergent before trying to decal it.
As to the decal I have seen ordinary bond paper treated with a dilute white wood glue solution used as the carrier. The image is laser printed in reverse onto the carrier. It is transferred via an iron on process to bond to the metal and then soaked in water to dissolve the white glue and release the bond paper.
For my use I have a CNC engraver. With aluminum I engraved it before having it anodized. Then the engraving is filled with white crayon.
The other process is to reverse print on a transparent film and glue this to the panel. That leaves the clear plastic exposed and protecting the text. The fancy version gets the text side painted with care and a light coat to avoid desolving the print. With masking sections may be different colors or even more advanced graphics done.
So I would clean the panel with a mild solution of that or a strong dish washing detergent before trying to decal it.
As to the decal I have seen ordinary bond paper treated with a dilute white wood glue solution used as the carrier. The image is laser printed in reverse onto the carrier. It is transferred via an iron on process to bond to the metal and then soaked in water to dissolve the white glue and release the bond paper.
For my use I have a CNC engraver. With aluminum I engraved it before having it anodized. Then the engraving is filled with white crayon.
The other process is to reverse print on a transparent film and glue this to the panel. That leaves the clear plastic exposed and protecting the text. The fancy version gets the text side painted with care and a light coat to avoid desolving the print. With masking sections may be different colors or even more advanced graphics done.
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