×
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

Surface Roughness (Ra) vs. Abrasive Grit Number

Surface Roughness (Ra) vs. Abrasive Grit Number

Surface Roughness (Ra) vs. Abrasive Grit Number

(OP)
I'm having trouble locating a table correlating these two items I feel I can trust.
My interest is for steels soft or hard, using SiC abrasives, emery cloth, even Scotchbrite.
Thanks in advance for any data or links.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: Surface Roughness (Ra) vs. Abrasive Grit Number

The only thing I have that is anything close is from the "Society of the Plastic Industry", it is a mold finish chart that relates Ra values to the surface finish material used on the molds.
i.e. if you are looking for a plastic part with an Ra of 4 to 5 you would want to finish your mold surfaces with a #400 grit paper, Ra of 38 to 42 use a #320 grit stone, etc.

RE: Surface Roughness (Ra) vs. Abrasive Grit Number

Table 3 from the link provided by XL is similar to what we use.
For example, when we want a #4 finish (which we consider that about 20-25 microinch Ra) we use 180 grit dry or 120 wet.
To achieve finishes <10 microinch we polish in stages and finish with wet 320.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: Surface Roughness (Ra) vs. Abrasive Grit Number

(OP)
Further googling located this and this.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

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! Already a Member? Login


Resources

White Paper – Data Security and Know-How Protection
Our data is constantly exposed to the danger of being intercepted or stolen as it wends its way over global data networks. Data security measures and measures for protecting intellectual property should not, however, first be implemented when data is exchanged – companies must lay the foundation for these measures within their own organization. Download Now
White Paper – Collaboration in the PLM Context
The influence exerted by the Internet of Things (IoT) means that there is a steadily growing need for collaboration in industry. Partners from new industries and areas of application need to be integrated in cross-company business processes to ensure that the lifecycle of smart, connected products can be managed from end to end. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close