Jump to content

Crafting Thread -- Ask Questions About Casework and Whatnot Here ...


dsavitsk

Recommended Posts

  • 3 months later...

Question about aluminum surface finishing
 
I've had this front panel CNC milled, it's  for a Beta 22 amp that I'm building.  I'd like to give it a "frosted" type finish, like I've seen on various pieces of gear. 
 
I've done some reading and after I clean up the milling marks with sandpaper of increasingly finer grades, there are two ways I can go (well, two and a half really...) 
 
1. Chemical etch  using sodium hydroxide. 
2. Media blasting.  (Bead blasting or some other media)
and the 0.5  is - I will likely have a clear anodize finish done after the surface is appropriately "matte / frosted"
 
But maybe I don't even NEED the bead blasting or chemical etch - one of the steps in anodizing is a light etch.   So I dunno, what's the best way to proceed?
 

smallface.jpg

Link to comment
Share on other sites

I think that once you sand out the milling pattern, you could probably use some 320 grit sandpaper to achieve the frosted look you want. use a block of wood or a sanding block, and keep the block moving in one direction (you can use that bump out at the bottom as a guide for the sanding block). I think that the clear anodizing is a good idea to harden the finish.

Link to comment
Share on other sites

I think that once you sand out the milling pattern, you could probably use some 320 grit sandpaper to achieve the frosted look you want. use a block of wood or a sanding block, and keep the block moving in one direction (you can use that bump out at the bottom as a guide for the sanding block). I think that the clear anodizing is a good idea to harden the finish.

 

I think sanding will produce more of a "brushed" final look.

 

Reading more about aluminum surface finishes for architectural uses ( http://gjames.com/aluminium/surface-finishing )  I think what I want is a media blast followed by clear anodizing.

 

Now I've got to find a place in the Chicago area that will do media blasting on one-off small jobs and then find a place to do the anodizing.

 

That lower area- which actually stands out 1/8" from the rest of the panel-  I am going to mirror polish that.

Edited by Milosz
Link to comment
Share on other sites

  • 3 weeks later...

For some reason.... both Camepert and FPE managed to mess up my order.... Because of the screw up camexpert did with my KGSSHV panels, I went with FPE for my Balanced Dynahi panels...

All the holes that are drilled are perfect... but they forgot a hole! They didn't drilled the key slot for the pot! Now the pot sits too high and the threaded portion is blocked by the panel aka can't be tighten down. E-mailing them about it now... why does this kind of things keep happening to me... why can't they just read the files as they are... :palm:

Edited by jwzhan
Link to comment
Share on other sites

Don't get me started on front panel today.  My laser guy decided go cheap and only placed the color film on the spots that were going to be marked.  It's pretty much silkscreen by laser but then he has to submerge it in a solution to clean it all off.  That solution oxidized the panels but only where there was nothing to cover them so hello patchy panels.  Time to find somebody else to do this... 

 

As for the volume knob guide pin, just cut it off.  No need for it if you can secure the pot properly. 

Link to comment
Share on other sites

Huge thumbs up to FPE! They provided me with an overnight ups label free of cost, took one day to finish the re-fab, and mailed it back immediately via overnight ups again. Turn around time was merely 2 days! That'a also including my added fabrication to deepen one of the the cavities, which they only charged $3 for. That's not even enough to cover the shipping! I wish CamExpert did the same with their mistakes. I'm definately only going with FPE from now on.

Link to comment
Share on other sites

Huge thumbs up to FPE! They provided me with an overnight ups label free of cost, took one day to finish the re-fab, and mailed it back immediately via overnight ups again. Turn around time was merely 2 days! That'a also including my added fabrication to deepen one of the the cavities, which they only charged $3 for. That's not even enough to cover the shipping! I wish CamExpert did the same with their mistakes. I'm definately only going with FPE from now on.

 

 

Yeah, but CamExpert are significantly cheaper, I get a good service from them anyways.

 

Glad to hear you got your panel fixed.

Link to comment
Share on other sites

  • 1 month later...
  • 9 months later...
  • 1 month later...

Maybe keeping such things in one place will prove helpful? Maybe not.

Anyway, to get the ball rolling, does anyone have a technique for removing a snapped off 4-40 tap from extruded aluminum side rails? Maybe the sort of kit one uses for removing stripped screws would work, but there is no head, essentially. Any other thoughts?

 

How to dissolve a tap embedded in aluminum: http://www.forkrobotics.com/2013/04/dissolve-a-tap-broken-in-makerslide/

  • Like 2
Link to comment
Share on other sites

  • 1 month later...
  • 11 months later...

I need some precision drilling done on an angle bracket. I don't think FPE will be able to handle this sort of job, can anyone recommend someone that might be able to assist? It really isn't a matter of milling, just pretty complicated hole patterns that won't have as much play as a typical row of TO-220 devices, so need more stringent tolerance than I know I can get with a drill press...

Link to comment
Share on other sites

Yeah, I figured. I was curious if any of the DIY setups could handle this? I would actually prefer a T Bar extrusion to an L, but the question is if the clearances work out. I need to do some math and figure out the minimum dimensions I need and match this up against common sizes and see what my real requirements are.

Link to comment
Share on other sites

I've been able to get really great results on my drill press, but there are a couple of steps.  I mark with a caliper, then using a sharp centering punch and a loop I make an indent.  I then use a 1/8" center drill followed by a larger 1/4" center drill if needed. 

When I was building my mill there really wasn't much room for error and this seemed to work pretty well, though not perfectly.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.