CNC Metal Engraving
|Bruce Stephenson||12/02/2021 15:10:01|
|21 forum posts|
I am looking at different solutions to get some instrument faces made up for an old aircraft. I need to get a couple of instrument faces cut into 0.8mm brass plate.
|Brian H||12/02/2021 15:24:04|
2147 forum posts
Hello Bruce, you have a P.M.
|Bill Phinn||12/02/2021 16:11:09|
|512 forum posts|
I too would welcome some recommendations on that score for doing deep and intricate relief engraving on small [max. one inch square] brass plate.
|geoff adams||12/02/2021 16:27:14|
|207 forum posts|
used to work for negretti aviation many years ago and used a alexander engraver for dials now i use my cnc mill for engraving today made a disc for my dog he lost another one post some pics of want you need i might be able to help
|Peter Greene||12/02/2021 17:02:23|
|209 forum posts|
If you are referring to the 3018 series and other similar machines, be careful. Those machines, while they basically function tolerably well, have no provision for levelling the bed other than a multitude of assembly screws. You'll go slowly mad.
... and engraving is particularly sensitive to bed-levelling since it directly affects the width of the engraved line.
Either be prepared to come up with you own mods for levelling or (as I've seen suggested) mount a sacrificial plate on the bed and machine all over with a cutter in the spindle to produce the needed level surface.
|Bob Stevenson||12/02/2021 18:12:58|
|514 forum posts|
CNC engraving may not be the best way to do this, either from cost or quality as there are some interesting alternatives used by clock makers. Also, there are dedicated clock face remakers who do only this task.
Simple methods you can do yourself are; ..acid etching using an light sensitive mask frrom a drawing or photocopy of an original........The brass workpiece is prepared and sprayed with light sensitive emulsion from a spray can,......the drawing is photocopied onto a transparent sheet (at your friendly local copy shop)........this transparency is placed over the prepared brass and exposed to sunlight for 5 mins,....the brass is slid into a solution that dissolves the unexposed details........the piece is then placed in the acid and the design etched........finally black compound is used to fill the etch.
An even better modern alternative is to make up your own transparency by photo-copying the design onto special paper which cost about 80p for each A4 sheet then place in warm water and slide off onto the brass (or other) sheet.
|Rik Shaw||12/02/2021 19:08:42|
1425 forum posts
"and engraving is particularly sensitive to bed-levelling"
Unless you use a spring loaded drag engraving tool. I made my own to engrave some numbers on a curved surface only this week. To see what it could do first though I stuck this piece of 5.5" x 6" ally sheet down on a bit of MDF - no attempt at leveling and let it go. Apologies for poor pic quality but our conservatory is a bit gloomy this time of night.
Machine is ISEL CPM 2018
|Adam Mara||13/02/2021 12:38:01|
|146 forum posts|
Don't know if this would an option, but my sons company uses a UV flatbed printer to print images on small jewellers brass plates for a local stutuette manufacturer. The brass is ready laquered, and the print can be laquered as well if required. Its normally used for plastics and anodised aluminium, but they have not tried plain brass or stainless steel yet!
|roy entwistle||13/02/2021 16:01:59|
|1352 forum posts|
I remember Poperhinge Barracks well 1955 - 1957
Roy ( Bass Trombone REME Staff band )
|john fletcher 1||13/02/2021 16:26:05|
|685 forum posts|
I was at Arborfield in 1953 waiting to go to Egypt, TEK, apparently its all gone, no doubt housing. John
|Rik Shaw||14/02/2021 17:02:23|
1425 forum posts
Recruit instructor 1967-8. Housing estate now. Bramshill Hunt is still there but permanently shut. It was only us lot that kept it going anyway
|Bruce Stephenson||21/02/2021 18:50:31|
|21 forum posts|
Thanks for the answers guys. My computer has been sick, so havent been able to keep up with this thread. Thanks so much for the offers so far. I hope to get on with converting inner workings into the old casings soon, so will need to get the instruments on to the test equipment and calibrate new cards for the new faces. It may take some time!
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