×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Acid etching wet cast concrete pavers?

Acid etching wet cast concrete pavers?

Acid etching wet cast concrete pavers?

(OP)
We are experiencing difficulties acheiving a consistent acid etch on the surface of our pavers. Does anyone have experience with application methods for acidic solutions to pavers that will give an even overall texture? Both brush and spray applications have resulted in patchiness related to the time of reaction, multiple applications seem to make the problem worse. At the moment it seems to relate to the method of application rather than variations in the density of the face of the paver. All suggestions welcome.

RE: Acid etching wet cast concrete pavers?

hiner...the problem is not your application but the variable density of the pavers.  They accept the acid differently so the response is different.  If they have not coarse aggregate in them, that won't change.  If they have coarse aggregate in them, etch until the aggregate is exposed.  That will mask the variability.

RE: Acid etching wet cast concrete pavers?

(OP)
Thanks Ron, we are after a fairly light etch to give a simulated natural stone finish, by the time we get an appropriate etch depth all over the face by reapplying we have large areas over etched. We need to avoid exposing the aggregate too much for the required effect. The patchiness appears visually to correspond with the timing and thickness of application rather than what you might expect to see from surface density variations.

RE: Acid etching wet cast concrete pavers?

What is your etchant?

I used a jelling agent and wetting agent in several etching jobs on concrete to apply different coatings, epoxies and vinyl ester.

RE: Acid etching wet cast concrete pavers?

(OP)
We have trialed Hydrochloric acid, neat and diluted. Also a Hydrochloric based product with a fuming inhibitor, which also seemed to have the same application problems but without the noxious fumes. Do you etch wet or dry. How do gelling agents work?

RE: Acid etching wet cast concrete pavers?

A jelling agent works by increasing the viscosity and tackiness of the liquid.  This in turn will slightly slow the action of the acid and help with keeping the etchant's action even. The wetting agent also helps keeps the action even.

I'm trying to find my information on tests with different acids or combinations we used.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources