Peter Daniel said:
Ohh Peter...please dont do that...i guess we all like you here...and if you keep on using paint thinner while using your belt sander...we suddenly wont have you around for a while. An electrical motor makes sparks, and a belt gets static....more sparks.
I have seen it blow up in the face of a guy using a powerdrill...not a nice sight.
How were your experiences with anodising at home?? easy?? cheap?? deadly poisonous??
Magura
I started using Varsol after the recommendation from a commercial place that do metal finishing.
I dont know what VARSOL is, but i sure hope its not flameable like paint thinner.
I usually use petroleum(kerosene) it works well, is easy to clean of and is almost impossible to ignite.......and it isnt paticulary poisonous (unlike paint thinner, wich is not for home use, since the fumes are very toxic).
Magura
I usually use petroleum(kerosene) it works well, is easy to clean of and is almost impossible to ignite.......and it isnt paticulary poisonous (unlike paint thinner, wich is not for home use, since the fumes are very toxic).
Magura
Have you looked at the MSDS for Varsol? Not very nice stuff to come in contact with. Any solution to this? I would think even latex-type gloves would be even more dangerous than the varsol.
Accept the fact that your hands will eventually fall off if using kerosene or varsol....but you got a nice looking amp 😀
Magura
Magura
Peter, just take it to a shop that does grain sanding and alodine coating....There is an art to grain sanding and worth the minimums involved in graining and coating......My shop has a $25 minimum......Don't care for alodine coating as either bright silver or gold as I recall.....Like it either black or clear anodize.....
rcrump said:
I tried most shops in my area (including the one that does Sonic Frontiers ). Unfortunately, I wasn't always happy with the quality of their job.
The plates had to be redone, anodising had to be stripped, brushed again and anodised again. It all took additional time, so now, when doing prototypes and small runs, I prefer to do finishing myself.😉 The good part is that I can have it all done in one sfternoon, without waiting a week or two for metal finishers. You know how it is, when only chassis keeps you from listening to your next creation.
BTW, I think I mastered the art of grain sanding pretty well😉
The minimum they charge here is $75 -100 CAD. Of course if it's 20 pcs or more, I'm not trying to do it myself.
I have had some trouble as well with finishing, but finally found a good shop to do the grain sanding and anodize work. I still have to run all over the place with knobs as have to be bead blasted, have lines engraved in them, then anodized and then paint filled......Three different shops involved......The grain sanding/anodize shop have $25 minimums, the bead blasting is $15 and engraver wants $50 minimum.....Runs about $300 to have our two chassis 60 pound preamp chassis finished and engraved.....Found a guy with a pantograph machine who does nice engraving and normally have it engraved through the anodize with the black anodized units. No set-up involved so each unit can be touch different as respects the lettering....`
Anodizing is an electrochemical process that changes the chemistry of the aluminum, in such as way as to make a very hard surface. It creates an oxide layer that is pretty tough.
IOW......scratch resistant, etc.
Alodine is a simpler operation that just puts a nice finish on aluminum, but can easily be scratched.
Alodine is basically a dip. Anodising requires electrolysis.
Typical application:
Front panel: anodise. It has to be able to withstand handling and abuse.
Metal parts inside unit: alodine. Shiny enough, but will not withstand scratches. Mostly to prevent oxidation of the surface.
Jocko
IOW......scratch resistant, etc.
Alodine is a simpler operation that just puts a nice finish on aluminum, but can easily be scratched.
Alodine is basically a dip. Anodising requires electrolysis.
Typical application:
Front panel: anodise. It has to be able to withstand handling and abuse.
Metal parts inside unit: alodine. Shiny enough, but will not withstand scratches. Mostly to prevent oxidation of the surface.
Jocko
The difference between anodizing and alodine could be compared to treating wood with hard lacquer or using sealer.
Alodine has effect of the sealer. It penetrates surface of aluminum, but does not create any protective surface like anodizing. That's why it is not a protection against scratches at all.
What I find appealing though is the simplicity of applying. Just dipping for few seconds is enough, and to me, it sometimes creates nicer finish than anodizing.
I usually brush it off a bit with scotch brite pads, after applying, and this removes any goldish shine. The aluminum looks more like stainless steel and is completely resistant to stains when handling. As long as you take enough care not to scratch it, it is a cheaper alternative to anodizing.
This panel was treated with alodine:
Alodine has effect of the sealer. It penetrates surface of aluminum, but does not create any protective surface like anodizing. That's why it is not a protection against scratches at all.
What I find appealing though is the simplicity of applying. Just dipping for few seconds is enough, and to me, it sometimes creates nicer finish than anodizing.
I usually brush it off a bit with scotch brite pads, after applying, and this removes any goldish shine. The aluminum looks more like stainless steel and is completely resistant to stains when handling. As long as you take enough care not to scratch it, it is a cheaper alternative to anodizing.
This panel was treated with alodine:
Attachments
bigger plate...a suggestion
take a bigger plate (bigger than required) do the finishing/brushing first and then cut it to size. this will get rid of the problems at the edges. Needless to say; cutting job should be perfect.
take a bigger plate (bigger than required) do the finishing/brushing first and then cut it to size. this will get rid of the problems at the edges. Needless to say; cutting job should be perfect.
I am digging out this old thread because I have had very bad experiences with professional anodizing companies.
Did try eight so far here in Germany, especially with brushing I got bad results. The problem (in fact it is not a problem but the result
of cutting cost and producing high quantities) is that there are no good brushers around.
Being a brusher was a qualified job once. I did once show a glossy, deep black, brushed Nakamichi front panel to an anodizer.
He believed it was painted.
It is not. The anodizing layer is 15µm. BTW, the thicker the layer, the duller the aluminium. Another anodizer even thought the upper lid of my Macbook, shown as another reference, was made of plastic. Just imagine - people doing this job and not being able to tell well made aluminium surfaces from paint or plastic. Anyway, I never met an anodizer who was able to produce according to the normal standard of the seventies and eighties. As one example, you won´t find true, deep blacks in anodizing any more. The only company I was in contact with that is able to produce glossy surfaces with brushing and anodizing is in South Korea.
But they only brush large quantities in automated assembly lines, not single pieces individually by hand.
Thus I want to try it myself, building a gauge for my parts to get the lines straight.
Something that obviously no anodizer does. I think two companies admitted that brushing is done "free hand"
without the aid of a gauge to keep the parts straight on the belt
But I am worried about the solvents to use to get a glossy brushing.
I think petroleum was mentioned, but I would like to use a water based solvent that can be easily rinsed.
Maybe there are sovents which allow the "O" in H2O not react so quickly with the aluminium?
For milling, some 10% oil-90% water solvents are used, but they are not healthy.
Also I do not want to give an anodizer the pretence to clean an "oily" surface prior to anodizing.
This is done with acid, followed by a second step using a base to strip the natural oxyde layer from the aluminium.
Then Comes then step of anodizing, building a new, even and thick oxide layer.
The lesser the aluminium is dipped in acid, the shinier it will become in the end.
Many parts I gave to anodizers became very dull becaus they clean them too long in acid.
I would really like to brush under running water, using some Kind of Soap that does not make chalk. Any ideas?
Did try eight so far here in Germany, especially with brushing I got bad results. The problem (in fact it is not a problem but the result
of cutting cost and producing high quantities) is that there are no good brushers around.
Being a brusher was a qualified job once. I did once show a glossy, deep black, brushed Nakamichi front panel to an anodizer.
He believed it was painted.
It is not. The anodizing layer is 15µm. BTW, the thicker the layer, the duller the aluminium. Another anodizer even thought the upper lid of my Macbook, shown as another reference, was made of plastic. Just imagine - people doing this job and not being able to tell well made aluminium surfaces from paint or plastic. Anyway, I never met an anodizer who was able to produce according to the normal standard of the seventies and eighties. As one example, you won´t find true, deep blacks in anodizing any more. The only company I was in contact with that is able to produce glossy surfaces with brushing and anodizing is in South Korea.
But they only brush large quantities in automated assembly lines, not single pieces individually by hand.
Thus I want to try it myself, building a gauge for my parts to get the lines straight.
Something that obviously no anodizer does. I think two companies admitted that brushing is done "free hand"
without the aid of a gauge to keep the parts straight on the belt
But I am worried about the solvents to use to get a glossy brushing.
I think petroleum was mentioned, but I would like to use a water based solvent that can be easily rinsed.
Maybe there are sovents which allow the "O" in H2O not react so quickly with the aluminium?
For milling, some 10% oil-90% water solvents are used, but they are not healthy.
Also I do not want to give an anodizer the pretence to clean an "oily" surface prior to anodizing.
This is done with acid, followed by a second step using a base to strip the natural oxyde layer from the aluminium.
Then Comes then step of anodizing, building a new, even and thick oxide layer.
The lesser the aluminium is dipped in acid, the shinier it will become in the end.
Many parts I gave to anodizers became very dull becaus they clean them too long in acid.
I would really like to brush under running water, using some Kind of Soap that does not make chalk. Any ideas?
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The anodizer I use locally is "Pittsburgh Anodizing" I think their minimum is $75.00. I think their charge is around $.035 per square inch.
They use a black dye from Sandoz to get the color they like that does not easily fade even in sunlight. This is a cosmetic anodizing with a thin anodized layer. For the "Thick" the aluminum self colors. That means it really is the alloy that determines the final color.
The process they use is light anodize, dip in color tank and then into a sealant tank. They also do a few other colors.
Brushing is a different matter. Most folks just use a belt sander with a 120 grit belt to carefully brush the surface. Some just sand by hand on the bare aluminum. I used to have a flap wheel sander not too dissimilar from a "Time Saver" but lost it in a flood. I usually sand the entire aluminum panel before punching, cutting it etc.
Attached is an amplifier I built with their anodizing. (Very low resolution! Old picture, old camera.)
They use a black dye from Sandoz to get the color they like that does not easily fade even in sunlight. This is a cosmetic anodizing with a thin anodized layer. For the "Thick" the aluminum self colors. That means it really is the alloy that determines the final color.
The process they use is light anodize, dip in color tank and then into a sealant tank. They also do a few other colors.
Brushing is a different matter. Most folks just use a belt sander with a 120 grit belt to carefully brush the surface. Some just sand by hand on the bare aluminum. I used to have a flap wheel sander not too dissimilar from a "Time Saver" but lost it in a flood. I usually sand the entire aluminum panel before punching, cutting it etc.
Attached is an amplifier I built with their anodizing. (Very low resolution! Old picture, old camera.)
Attachments
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The color is from Sandoz is probably called Sanodal. Here in Germany, usual dyes are electrolytic, using tin-sulfate.
But it is not clear to me, whether Sanodal is also sulfate-based. People who anodize as a hobby use sometimes fabric color.
Works but is not resistant to sunlight and will fade over time.
But the last professional anodizer I met did not guarantee that his sulfate based black will not fade.
Yes, the alloy can self color with thickness. Pure aluminium will not self color
much, an aluminium alloy with a fraction of other metals will not self color as well.
AlMgsi0,5 and AlMgSi0,7 are very often used for front panels.
They do not self color besides hard coating, a special treatment that allows
oxyde layers up to 300µm.
AlZnMgCu1.5, used in aviation, is one of the strongest aluminium alloys.
Even with thin oxide layers it shows an olive like color when being anodized.
Problem with most companies: They have their routines and "sell" you variants as impossible.
Company A tells you that AlMg3 (a cast aluminium alloy, good to mill) will always be dull when anodized.
Company B proves the opposite but lacks other skills...
This is a sample I got, from a German company.
I did provide the plate, the AlMg3 mentioned
Shiny, but not well brushed. See the "gepunktete Bürststriche",
the dotted lines?
The same plate, another german anodizing company:
Crap. The "graue Schliffriefen", the grey sandings grooves behaved like chalk. Probably not sealed after anodizing.
Again the same plate, third german anodizing company:
The gloss is acceptable but are this really straight lines?
I doubt anyone who brushes himself as a DIYer would be satisfied with this...
The following is what I saw from the Korean company Pavonine @IFA german consumer electronics fair.
Aurender and probably Samsung are their customers
A close up, also Pavonine, nice:
Did not get this perfect finish from any sanding shop and anodizer in my country yet.
There might be some, a few rejected me because i have only a few parts to offer...
But it is not clear to me, whether Sanodal is also sulfate-based. People who anodize as a hobby use sometimes fabric color.
Works but is not resistant to sunlight and will fade over time.
But the last professional anodizer I met did not guarantee that his sulfate based black will not fade.
Yes, the alloy can self color with thickness. Pure aluminium will not self color
much, an aluminium alloy with a fraction of other metals will not self color as well.
AlMgsi0,5 and AlMgSi0,7 are very often used for front panels.
They do not self color besides hard coating, a special treatment that allows
oxyde layers up to 300µm.
AlZnMgCu1.5, used in aviation, is one of the strongest aluminium alloys.
Even with thin oxide layers it shows an olive like color when being anodized.
Problem with most companies: They have their routines and "sell" you variants as impossible.
Company A tells you that AlMg3 (a cast aluminium alloy, good to mill) will always be dull when anodized.
Company B proves the opposite but lacks other skills...
This is a sample I got, from a German company.
I did provide the plate, the AlMg3 mentioned
Shiny, but not well brushed. See the "gepunktete Bürststriche",
the dotted lines?
The same plate, another german anodizing company:
Crap. The "graue Schliffriefen", the grey sandings grooves behaved like chalk. Probably not sealed after anodizing.
Again the same plate, third german anodizing company:
The gloss is acceptable but are this really straight lines?
I doubt anyone who brushes himself as a DIYer would be satisfied with this...
The following is what I saw from the Korean company Pavonine @IFA german consumer electronics fair.
Aurender and probably Samsung are their customers
A close up, also Pavonine, nice:
Did not get this perfect finish from any sanding shop and anodizer in my country yet.
There might be some, a few rejected me because i have only a few parts to offer...
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Not done by myself but I was present: my former business partner got into Pro PA/Recording equipment (I stayed with MI amps), among other things he made single chnnel mixer strips in a variery of flavours, including some "old Neve type", he machined his front panels out of 3 to 6 mm thick aluminum and had it anodized, usually black which is the most difficult colour to get right.
I went with him to this huge anodizing plant, specialized in 6 to 12 meter long architectural extrusions, who agreed to hang his stuff from a hook in a large tank when "something else" (I mean a paying customer 😉 ) was being processed.
They didn´t actually charge him, since any amount would be ridiculous compared to minimum batch which was in the order of hundreds of kilograms, but of course, he always showed up with a good whisky bottle or a couple fine wine ones, so he was always welcome.
Finish was stunning, fwiw our reference quality level was 80`s Japanese stuff (Sansui, Pioneer, Kenwood, Nakamichi) so it *can* be done.
That said, they were *very* fussy about aluminum alloy used, saying that such results were impossible on most alloys, no matter what pigment or process was used, so they sent him to a supplier which stocked the "good" aluminum.
They also phoned him so he would sell small amounts (labelled as "samples" ) to my friend.
He scratched/polished aluminum surface before CNC machining , not with a belt which he didn´t like because it *scratched* surface too much but with cylindrical relatively soft rotating brushes or, for "scratched but smooth finish" what could be described as a "wooden broomhandle covered in steel wool".
He made a small sliding tray to push aluminum smoothly and in perfectly parallel path against the counter rotating brush or "polisher".
Being custom jobs, he did not use silkscreen but CNC engrave letters which either were left aluminum-on-black or filled with what looked like (and probably were) children´s wax crayons.
He slightly warmed aluminum before this.
Hope some of this helps, most important point is "get the proper aluminum first".
At least a few anodizers "should" know it from this description and know how to find it in Germany; Argentine type and model won´t help you.
I went with him to this huge anodizing plant, specialized in 6 to 12 meter long architectural extrusions, who agreed to hang his stuff from a hook in a large tank when "something else" (I mean a paying customer 😉 ) was being processed.
They didn´t actually charge him, since any amount would be ridiculous compared to minimum batch which was in the order of hundreds of kilograms, but of course, he always showed up with a good whisky bottle or a couple fine wine ones, so he was always welcome.
Finish was stunning, fwiw our reference quality level was 80`s Japanese stuff (Sansui, Pioneer, Kenwood, Nakamichi) so it *can* be done.
That said, they were *very* fussy about aluminum alloy used, saying that such results were impossible on most alloys, no matter what pigment or process was used, so they sent him to a supplier which stocked the "good" aluminum.
They also phoned him so he would sell small amounts (labelled as "samples" ) to my friend.
He scratched/polished aluminum surface before CNC machining , not with a belt which he didn´t like because it *scratched* surface too much but with cylindrical relatively soft rotating brushes or, for "scratched but smooth finish" what could be described as a "wooden broomhandle covered in steel wool".
He made a small sliding tray to push aluminum smoothly and in perfectly parallel path against the counter rotating brush or "polisher".
Being custom jobs, he did not use silkscreen but CNC engrave letters which either were left aluminum-on-black or filled with what looked like (and probably were) children´s wax crayons.
He slightly warmed aluminum before this.
Hope some of this helps, most important point is "get the proper aluminum first".
At least a few anodizers "should" know it from this description and know how to find it in Germany; Argentine type and model won´t help you.
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Before the flood I built a sander out of flap wheels on a shaft turned by a 3750 watt DC motor designed for a treadmill. Easy to make it variable speed up to 3,500 RPM.
I used long under drawer slides to move a table in and out with a bit of precision.
A simple height and speed adjustment allowed me to control the finish. But I brushed the aluminum before other processing to avoid the rounded edges.
When I couldn't do that I would machine a surrounding carrier plate to keep the edge surfaces level.
I think my total cost for all the sander parts was under $300.00. But I got the motor surplus for $10.00!
BTY my anodizer firm settled on their dyes because a local optical company had some products sitting in their warehouse for a few years and the side facing the window faded.
They pride themselves on their quality and do keep a chemist on staff. They do not brush, but there is another place down the street from my shop that will, but I have never tried them. They mostly finish steel products and stainless steel is almost always wet brushed finished.
Today I scratched a small stainless wall plate while drilling it so I brushed it with a "Scotch Brite" abrasive pad.
Some years back we did wall plates for a NYC art museum. Originally the plate finish request was black anodized aluminum. After shipping those it got changed to a special extra white. So they changed to painted steel. Next came a few other plates in different colors and finally one in mirror polish stainless steel.
What does not translate well is the aluminum identification system.
Normal cheap sheet aluminum is 5052 alloy, most common 6061, 1000 series is pure aluminum, real aircraft 7075 but the older version is 2024 which really polishes up to a very nice finish. It is the alloy I would use for front panels but I suspect since the primary alloy element is copper it may be one that tints a bit green.
An explanation of alloy numbers may be found here: http://www.esabna.com/us/en/education/blog/understanding-the-aluminum-alloy-designation-system.cfm
I used long under drawer slides to move a table in and out with a bit of precision.
A simple height and speed adjustment allowed me to control the finish. But I brushed the aluminum before other processing to avoid the rounded edges.
When I couldn't do that I would machine a surrounding carrier plate to keep the edge surfaces level.
I think my total cost for all the sander parts was under $300.00. But I got the motor surplus for $10.00!
BTY my anodizer firm settled on their dyes because a local optical company had some products sitting in their warehouse for a few years and the side facing the window faded.
They pride themselves on their quality and do keep a chemist on staff. They do not brush, but there is another place down the street from my shop that will, but I have never tried them. They mostly finish steel products and stainless steel is almost always wet brushed finished.
Today I scratched a small stainless wall plate while drilling it so I brushed it with a "Scotch Brite" abrasive pad.
Some years back we did wall plates for a NYC art museum. Originally the plate finish request was black anodized aluminum. After shipping those it got changed to a special extra white. So they changed to painted steel. Next came a few other plates in different colors and finally one in mirror polish stainless steel.
What does not translate well is the aluminum identification system.
Normal cheap sheet aluminum is 5052 alloy, most common 6061, 1000 series is pure aluminum, real aircraft 7075 but the older version is 2024 which really polishes up to a very nice finish. It is the alloy I would use for front panels but I suspect since the primary alloy element is copper it may be one that tints a bit green.
An explanation of alloy numbers may be found here: http://www.esabna.com/us/en/education/blog/understanding-the-aluminum-alloy-designation-system.cfm