Re-anodising erroneously laser marked aluminium (aluminum) sheets.

[Dan Kozakewycz]

As I'm a complete n00b to the laser engraving game, I've been making a few mistakes with my products and as such I am getting a high wastage rate on my materials through silly mistakes. Each on of my plaques costs me £15 with a finished value of £150, and so far I've managed to scrap about 8 of them.

I am wondering if it would be possible to have the anodising chemically stripped from these plates and for them to be re-done, thus completely removing the marking and making it 'as new'.

Is there any reason that the laser marking may make this a non starter?

[Henri Sallinen]

The best approach would be to minimize the reasons you are making the mistakes. If you are using too little power on a run, you can allways run the same sign again (do this without moving the sign after the first run). If it's a alignment issue, you could try to make a jig out of some scrap material (corrugated cardboard or some spare plastics?) and align your artwork acording to the jig. This should minimize the mistakes you could be making. Also, make sure that there are no hidden layers or wrong colored layers that could give a faulty engraving quality.

No ideas on the re-anodising, sorry!

[Dave Sheldrake]

Yes you can Dan, they can be stripped with Hydroxide (Sodium) but will cost more to have them re-anodised than they cost you I would think.

Home anodising isn't expensive to set up and can be done for pennies once you have the kit

cheers

Dave

[Robert Walters]

Anodizing involves electrolysis, battery acid, flammable hydrogen gas, boiling water, and about 90 minutes.

I have no clue on Re-anodizing, but you might get inconsistent coloring batch to batch, and not sure on the lasering would effect it either; may leave artifacts that any "stripping" process may not be able to remove.

Unless you plan on making a LOT of mistakes, probably not worth the time and effort to recover the lost value.
Might be better to just reuse the plates for testing and calibration purposes, then just recycle the aluminum itself.

[Dan Kozakewycz]

The best approach would be to minimize the reasons you are making the mistakes. If you are using too little power on a run, you can allways run the same sign again (do this without moving the sign after the first run). If it's a alignment issue, you could try to make a jig out of some scrap material (corrugated cardboard or some spare plastics?) and align your artwork acording to the jig. This should minimize the mistakes you could be making. Also, make sure that there are no hidden layers or wrong colored layers that could give a faulty engraving quality.

No ideas on the re-anodising, sorry!

It's mostly errors I've made in the artwork, spelling mistakes, errant lines etc. My product is bespoke replica technical drawings which I draw myself, sometimes I make mistakes on it and don't notice until they've come out of the machine.

Yes you can Dan, they can be stripped with Hydroxide (Sodium) but will cost more to have them re-anodised than they cost you I would think.

Home anodising isn't expensive to set up and can be done for pennies once you have the kit

I got the anodising carried out by a different supplier from who supplied and laser cut the plaques. That company said they'd re-do them (they did some the wrong colour) for the same price but sadly they're out of action following a serious fire recently. Having trouble finding a replacement for the ones in the wrong colour at the moment but when I do I was hoping I could perhaps save a few of the cast offs by re-doing those too. So far I've had one company say it is possible and one say it isn't, so I'm a bit confused.

I do want to check home anodising out eventually, but at the moment I do not have anywhere to do this work safely. Maybe when I get a garage or unit to move in to in future.

Anodizing involves electrolysis, battery acid, flammable hydrogen gas, boiling water, and about 90 minutes.

I have no clue on Re-anodizing, but you might get inconsistent coloring batch to batch, and not sure on the lasering would effect it either; may leave artifacts that any "stripping" process may not be able to remove.

Unless you plan on making a LOT of mistakes, probably not worth the time and effort to recover the lost value.
Might be better to just reuse the plates for testing and calibration purposes, then just recycle the aluminum itself.

Yes this was my initial thought, I can keep errors as demo pieces if the mistakes are minor and as test material as if they're bad. Would just be nice if I end up with a stack of them, to be able to send them off next time I order a new batch for anodising and have them refinished.

[Dan Hintz]

So far I've had one company say it is possible and one say it isn't, so I'm a bit confused.

Absolutely, it's possible (and done often in the industry). The company that said 'no' simply doesn't want to do it (or isn't set up to do it, which is a real possibility).

[Michael Hunter]

Any anodiser should strip (at a charge) and re-anodise for you .

Unless you polish or linish the metal after stripping (and before re-anodising), you are likely to see a "shadow" of the previous engraving.
This may not be too much of a problem if the correct engraving goes right over the top of the mistake, but if it is in a different position it will show.

[John Coloccia]

Sell them for $40 as "scratch and dents". That's what I do with my products. I get enclosures all the time that have imperfections on them...probably 5% to 10% have some sort of issue. Instead of bothering with time consuming QC when they come in, return shipping, etc etc, I simply put them aside when I find them, and then build them up and sell them off as scratch and dent when I have a spare moment. I've still made money, and I have a happy customer that got a steal.

[Mike Null]

Dan

You've discovered one of the hazards of engraving--carelessness! All of us have made these mistakes and we have learned to proof our work over and over. Even then we make mistakes. Sometimes it's a machine malfunction or faulty material but most of the time it's just human error.

I would put those mistakes in the salvage barrel and not waste any more time or money on them.

[Dan Kozakewycz]

Sell them for $40 as "scratch and dents". That's what I do with my products. I get enclosures all the time that have imperfections on them...probably 5% to 10% have some sort of issue. Instead of bothering with time consuming QC when they come in, return shipping, etc etc, I simply put them aside when I find them, and then build them up and sell them off as scratch and dent when I have a spare moment. I've still made money, and I have a happy customer that got a steal.

Trouble is everything I do is totally bespoke, so once I've engraved it with all the customers details it's of no real appeal to anyone else unfortunately!

Dan

You've discovered one of the hazards of engraving--carelessness! All of us have made these mistakes and we have learned to proof our work over and over. Even then we make mistakes. Sometimes it's a machine malfunction or faulty material but most of the time it's just human error.

I would put those mistakes in the salvage barrel and not waste any more time or money on them.

A fair comment. I wouldn't bother sending them back normally but under the circumstances (about 25% of the plaques were dyed the wrong colour and need redoing) I thought I might as well get these bits redone at the same time.

Interesting to here that there may be some left over marks on the new surface. I guess I'll just need to test this out with a sample.

[Brian R Cain]

I can't add much to what has already been said other than to agree with Mike that it's probably not worth the effort and you have to put it down to experience. One thing I will say from my own experiences of having small numbers of items anodised is that the quality can be very variable. I've had parts of batches that were dark blue instead of black, streaks and so on. Never 100% of a batch having the same colour. I'm very impressed though that mass produced items such as pens are anodised so consistently well.

[Dan Kozakewycz]

I can't add much to what has already been said other than to agree with Mike that it's probably not worth the effort and you have to put it down to experience. One thing I will say from my own experiences of having small numbers of items anodised is that the quality can be very variable. I've had parts of batches that were dark blue instead of black, streaks and so on. Never 100% of a batch having the same colour. I'm very impressed though that mass produced items such as pens are anodised so consistently well.

Yes the anodising on this batch sadly wasn't up to the standard of the material I purchased from Trotec/Suregrave but unfortunately they weren't able to supply the material as I required it for the production work.

[Bill George]

Rustoleum sells a paint that looks almost chrome like. It comes in chrome and gold colors, looks pretty darn nice. Re purpose your sheets with paint and move on. I use scrap pieces of plywood spray painted for my testing of a concept or design.

[matthew knott]

Dont even bother trying, the stripping effects the surface finish of the aluminium, on sheet stock it will never be cost effective to get something stripped and re-anodized and get an even half decent finish. At £15 a sheet its better just to bin it and buy new again, we regularly have parts sent into us that have been stripped and re-anodized and you can always tell the difference.

[Dan Kozakewycz]

Oh that's not good at all Matthew. Ignoring the ones that have been marked on the laser, that doesn't bode particularly well for the 30 odd sheets that were supplied in the wrong colour.