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peterl
09-05-2013, 09:55 AM
Hi everyone

So I'm a cnc newbie and I'd like some advice for a project I have in mind, any help would be really appreciated


I would like to engrave patterns and words / logos onto bicycle components. I am a vintage bike restorer and there was a fashion for this in the 70s -80s, though at that time it was done using a pantograph machine

Firstly I would like to know if you think this is possible to do with a cnc machine ? Some surfaces will be flat but others may have a slight curve e.g. Down the length of a seat post or along the stem (see attached picture) is it possible to engrave on a curve surface using a spring loaded tool or something similar?

Secondly I would like to know what kind of machine I should be looking at. It only needs to be small for such parts. Roughly 300 x 300 mm. I have had a look at some cheap Chinese ones on ebay but am aware they have mixed reviews. I'm no electronics expert so am not that confident in building one myself! ( though not totally averse to it ) the most important thing is it is accurate .

Budget wise I would like to keep it as low as possible, is around £600 realistic ?

Thanks in advance


Peter 8892

GEOFFREY
09-05-2013, 11:53 PM
Hi Peter, yes you can engrave on a curved surface with a sprung loaded spindel. Ithink that if you look in the showcase forum, somebody has made a really nice version. I have a very old dahlgren engraver with this facility, but have not yet had time to make a new controller for it. If you do get a machine, it will probably need a fairly high Z clearance to accommodate whatever fixtures you need to hold your material ( I know that goes without saying, but Iv'e said it anyway). Goodluck. G.

Fivetide
10-05-2013, 12:45 AM
Hi Peter, yes you can engrave on a curved surface with a sprung loaded spindel. Ithink that if you look in the showcase forum, somebody has made a really nice version. I have a very old dahlgren engraver with this facility, but have not yet had time to make a new controller for it. If you do get a machine, it will probably need a fairly high Z clearance to accommodate whatever fixtures you need to hold your material ( I know that goes without saying, but Iv'e said it anyway). Goodluck. G.

I agree with Geof , in my limited experience Z height can be deceptively less than you image when you read the stats, it may say 500mm travel but take off the chuck overhang then the tool length and the board / vice /clamp you have mounted the work in/on, if you don't want to mill the bottom plate and its less than you think.