CNC Lettering

[andyrayk]

I have a few parts of 6061 T6 that have lettering engraved on a CNC mill.
I want the lettering to stand in contrast to the rest of the part which will be black
anodized. What is a good protective filler for the existing lettering? Wax or something like silicon rubber? If I used wax or parafin it would probably melt out but has anybody tried using the temperature indicating waxes used on hot metals?

[acidrain]

We typically use rubber cement (the cheap stuff for crafts... NOT contact cement).
You can thin it down by adding small amounts of lacquer thinner and stirring until you get the consistancy you want.
Be carefull... it will be stringy. After it's thinned, it will need a couple coats.
Ano your part normally, rinse and dry the part with a hair dryer, apply the mask with gloved hands, dye black.
Seal normally, then clean all the mask off the parts with lacquer thinner, then seal some more.
Let us know how your project turns out!

[destroyer125]

If your doing the CNC'ing yourself, you can always mill the lettering in after anodizing, which will give a shiney silver appearance on the aluminum with the black anodized finish around it. Its going to be hard even with thinned cement to get it only in the grooves.

[andyrayk]

Thanks for the replies both of you. I am doing my own CNC lettering and machining and now see the error of my ways in not doing the anod and dye first before the lettering.
I will try the rubber cement and post the results. Live and learn.

Here's an edit to my post...hmmmm after thinking it over it is probably a better option to remove the lettering (there is enough metal to do so) make a new
surface and then anod , dye and re-letter the part. Did not want to do this but it will probably give me the best result in the long run.

[luminous]

How deep is the lettering? Is the surface of the piece flat?

Could you turn it face down into a very shallow pan of dye, or maybe on to a heavily saturated felt pad so that the surface got dyed, but the letters were above the liquid level of the dye?

Just a thought...


steve

[andyrayk]

The part is 6 inch diameter and will be used as a retaining ring for a refractor telescope lens. The lettering is .012" deep and is cut curved around the part to be read as on a telephoto lens front end. I'm still thinkin' recut the surface and re-letter after ano and dye.
Thanks again for the input.

[luminous]

Sounds like a neat project. I think re cutting the surface, then ano, then re cut the lettering would produce the sharpest cleanest results and possibly with less hassle than trying to mask it. (Ain't CNC great!)

The anodized layer is hard as hell, and probably puts some wear on those little end mills, but it's thin so I imagine it's not too bad...

Don't forget to post a photo when you're done!


steve

[andyrayk]

'Anod the part, black dyed and re-cut the lettering and the whole job came out great but I still cannot post any pics of my stuff. My 'puter tries to upload but is blocked, (seems like Caswell's end). We're talkin' a 86kb jpeg here.
Is there a permission that must be obtained first? I have no problem with any other group site uploading pics if I'm logged in.

[acidrain]

I've never uploaded pics directly to the forum. Are you sure the height and width is within limits? Just a suggestion, but try disabling your firewall. I've had problems uploading my website to my host. One day I tried disabling the firewall, and then it worked fine.
For windows xp, click start> control panel> windows firewall> disable firewall. Don't forget to turn it back on after you try it.
Personally, I always use my own image host. I really like www.photobucket.com.
It's free, and you can upload many pics at once.

[IAMaxxer]

Originally Posted by andyrayk

'Anod the part, black dyed and re-cut the lettering and the whole job came out great but I still cannot post any pics of my stuff. My 'puter tries to upload but is blocked, (seems like Caswell's end). We're talkin' a 86kb jpeg here.
Is there a permission that must be obtained first? I have no problem with any other group site uploading pics if I'm logged in.

I have the same problem. I use photobucket and can't make the link. Have no trouble on other sites that use vBulletin....