etching info plates

[Graham Williams 5Participant @grahamwilliams5]

Just finished ALGOA gearbox for my ML7 and need to etch the info plates. Maplins doesn’t do the necessary chemicals anymore, RS sell only large amounts and nothing appearing on Ebay. Does anyone know where I can either purchase the chemicals in small qtys/at affordable money or someone who can mfg the plates for me ?

[Graham Williams 5Participant @grahamwilliams5]

[JasonBModerator @jasonb]

Maybe ME’s own Diane Carney can help as she is in the etching business.

 

http://www.loco-nameplates.co.uk/

 

J

[Martin WParticipant @martinw]

Graham

 

If its ferric chloride your after the CPC do various sizes of bagged pellets, see here.

 

Cheers

 

Martin

 

 PS

 

RS do it as well in various sizes see RS .

Edited By Martin W on 13/05/2011 10:39:56

[Graham Williams 5Participant @grahamwilliams5]

Thanks for the swift replies.

Jason :- I’ll try Diane Carney see if she’s able to provide them.

 

Martin:- According to Hemingway’s instructions I also need Sodium Hydroxide, and something called Photoresist Aerosol spray, all listed at RS but adds up to £39 1/2 which makes them expensive plates. CPC seems to be miles cheaper but only lists the Ferric Chloride as far as I can see. Perhaps I’m missing something about making these plates, is there a really simple/simpler method out there ?

 

Cheers

Graham W

[Martin WParticipant @martinw]

Graham

 

What is the base metal you are etching? If it is brass or copper then the Sodium Hydroxide is probably being used as a degreasing agent and I believe that there are other less corrosive products on the market that will do just as well.

 

CPC supply spray cans of photo-resist, see here Photo Resist, though this is listed as a photo positive so you will need to check whether you will need a positive or negative image screen.

 

My only experience of etching is from the electronics side of things using copper clad boards and we were producing very limited quantities for experimental work but still using basic kit in a lab. The thing is that everything must be clean and the material thoroughly cleaned and degreased before the photo resist is applied. We used strong detergent cleaners and fine abrasives to prepare the surface of the material then rinsed with distilled water and air dried in dust free atmosphere. That way we didn’t get hairline lands bridging tracks on the board.

 

Cheers

 

Martin

 

 

 

 

[Graham Williams 5Participant @grahamwilliams5]

Hi Martin.

 

0.021″ brass sheet is what I’ve got so have cut a shape to size. Positive Photoresist is what is listed to use along with the Sod.Hydroxide,which must be the degreaser, presume ferric chloride is also part of the process as that’s also listed. I couldn’t find anything other than the ferric chloride on CPC’s site, then again I’m not that good on searching. The link looks exactly what I need and cheaper than RS so Ta everso.

 

Also contacted Diane Carney as per Jason’s info so will make the choice when I know what she can do. Not overly fond of the chemical idea but needs must and the gearbox is compromised in use without any info plates.

 

Cheers

Graham W

[Clive HartlandParticipant @clivehartland94829]

Etching resist can be Bees Wax.

Warm the metal and apply a thin layer of bees wax.

You then need some method of creating the legend. Scratching through the wax or even engraving through the wax with a spring loaded sharp plunger.

I have only done this with thin line legend.

The etching medium I used was Aqua Regia, an acid mix and extremely dangereous.

This method was used as the base metal was hardened and was too hard to engrave.

 

I doubt this is any use on brass as a posting has just been put on the site as I was composing my post.

 

Clive

Edited By Clive Hartland on 13/05/2011 17:05:31

[John BaguleyParticipant @johnbaguley78655]

HI Graham,

 

The sodium hydroxide is to dissolve away the exposed photoresist once you’ve coated the plate and exposed it to the UV. The unexposed resist is unaffected. I use this process for making PCB boards.

 

I’ve recently used a process to make etched name plates using a product called PressnPeel which gave excellent results. You just need a laser printer to print your positive onto the PressnPeel. You then iron that on to the brass plate and peel off the carrier film which leaves the toner which acts as the resist. You then just etch it as normal. Much easier than the photo process.

 

http://www.modeng.johnbaguley.info/DIY%20Nameplates/nameplates1.htm

 

The only bit that needs care is the ironing on of the PressNPeel. Oh, and remember to make a mirror image of the lettering you want (don’t ask why!)

 

 

 

John

 

 

Edited By John Baguley on 13/05/2011 17:11:10

[Martin WParticipant @martinw]

John

 

Things have evidently moved on since I was prototyping pcbs, in those days we had to generate the masks photographically so it was a tedious process. I must admit I like the PressnPeel system you describe as it seems to do away with a lot of the problems of making a positive or negative transparent mask then exposing, developing, washing etc.

 

More or less print and etch, a much better idea.

 

Thanks

 

Martin

[michael howarth 1Participant @michaelhowarth1]

[michael howarth 1Participant @michaelhowarth1]

[michael howarth 1Participant @michaelhowarth1]

[michael howarth 1Participant @michaelhowarth1]

[michael howarth 1Participant @michaelhowarth1]

Graham,

 

You will probably know this already, but just in case you don’t, sodium hydroxide is

the same stuff as caustic soda, available cheaply at the likes of B&Q, Wilkinsons etc

It may not be as pure as lab quality but will probabl;y do the job just as well.

[Ian S CParticipant @iansc]

You’d proberbly do just as well degreasing with washing soda if you don’t feel happy using caustic soda. I got my Ferric Chlorride from the local chemist, it was old stock, he said his father used it as part of the cough mixture he used to make up, They do’nt make it like that these days! Ian S C

[Sub MandrelParticipant @submandrel]

I'll bump this as my experience today may be helpful

Photo-resist spray is available from Maplin (but not Farnell) after some almost-usable tries using the iron on laser print method (using normal paper, but softening with NaOH).

I normally use photo resist boards for PCBs, but this is my first try with the spray. I discover you need to use quite a good spray (~10 quick passes) or you get fuzzy results. The hardest bit is making sure the brass is dead flat so the positive (laser film) is pressed hard against the resist for sharp lines.

I'll post some pics when they come out of the ferric, and after they've been tidied up.

Neil

[Sub MandrelParticipant @submandrel]

This is straight from the ferric, looking a bit rough – the blue bits are dalo pen:

I've filed them out and quickly filled them in with magic marker – proper finish will have paint and a real polish. This is the maker's plate for the radiator, 1 1/2" across – I'm well chuffed with this:

The number plate from the side of the cab is just 3/4" across. The text isn't perfect, as the resist was sprayed on too thick. A better one is in the etch:

Even so, if the R and Y had come out it would have been better than the real plate I copied!

Neil

[Author]

Posts