Aside

Timing is Everything

We’ve been getting a lot of questions lately about Sandblasting. (especially since we launched the Free Gift Campaign)

Sandblasted rock by Russ LarsenSome Sandblasting Questions we’ve been getting include:

  • How long do I expose the resist film?
  • How long do I washout the resist film?
  • How long do I sandblast the design?
The answer to all these questions is, “Only as long as it takes to get the job done.”
Exposure
When you’re exposing resist film, you want to find that fine line when the film is exposed, but not over exposed. This is determined by several variables including:
  • Whether you are using transparency film or a more opaque paper
  • How dark the artwork is (or is you double it up as Russ does)
  • How thick the artwork lines are (finer lines and small designs may require a bit more exposure time)
Wine Bottle SandblastingRule of Thumb for Exposure and Washout when Sandblasting:
If your design washes away – expose longer.
If the washout process takes too long, expose shorter.
You need to experiment until you find that perfect exposure time when the washout process goes quickly without losing any of the design. However, as you can see in the video, doubling up your transparency film and exposing for 30 seconds works most of the time, but you may want to adjust depending on the factors mentioned above.
Washout
The key to washing out resist film is to wash just long enough to remove all the white, but STOP as soon as it is removed. The longer you continue to spray, the more the film is breaking down and the more risk you take of washing part of your design away. Wash until the design is clear, then STOP.
Rule of Thumb (again) for Exposure and Washout when Sandblasting:
If your design washes away – expose longer.
If the washout process takes too long, expose shorter.
If you cannot get the fines lines to stay in the design, you may need to adjust the artwork to make them thicker.
Sandblasting
Sandblast time is the same as the two processes above. As you sandblast the surface, the resist film is also being worn away. You can only blast so long before your resist film breaks down and you lose your design. The longer your blast, the greater the risk of losing part of the design (though it’s surprising how deep you can blast with only 3 mil film! – for deeper blasting, try the 5 mil film)
Once again, you are looking for that perfect time when the design is completely sandblasted – then STOP!
blast-book-2-500pix
The Good News
Once you’ve done this a few times, it’s easy. You’ll know what surfaces to sandblast, you’ll know the exposure and washout timing, you’ll know how to select artwork that will look good and you’ll know how long it will take to turn out a professional product – EVERY TIME.
In a Nutshell
If you want to learn sandblasting, you can. The key to¬†professional¬†results every time is to do each of the processes above ONLY UNTIL THEY ARE DONE – DON’T OVERDUE IT!
 

Be Sociable, Share!

    , , ,

    Comments are closed.