# Grind/Sand bevel concrete edge



## concretemasonry (Oct 10, 2006)

Normally, a chimney cap is poured in a steel or fiberglass form and poured upside down.

This allows the bottom (top as poured) to be edged. Usually a half round groove is make about 1" from the edge. This is done to create a drip and guarantee that water does not drip off the corner of the cap, but is dripping just out from the face of the chimney.

Since you do have a "drip" groove, you should put on a small bevel and hope the water does not get to the chimney (leakage, efflorescence , freezing damage). You still have to face the water that will not drip/drain properly and can find its way into the chimney itself.

The ground bevel will prevent the corner from raveling and falling off for visual purposes and should be adequate to get the home sold.

Dick


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## hardmat (Aug 8, 2014)

Hello Dick, thanks for the reply.

Which edge are you referring to that I should bevel for functionality? Let's reference everything as it sits now as far as top or bottom etc... 

The overhang of the Cap is made up of 2 - 2x4's (3"). The 2x4 closest to the chimney is a full 3-1/2 inches, the one right next to and thus furthest out from the chimney was ripped down to 3-1/4". The net effect, from the outside bottom surface of the chimney, the first 1-1/2" of that surface around the perimeter is a 1/4" lower than the inner 1-1/2". It steps up that 1/4" which I hope will cause any water that wraps around to the bottom to release at that point and fall, thus not making it to the brick outer chimney wall.

Dick, maybe you can help with my question regarding the "grinding" process. I will use a 4-1/2" Makita hand held grinder. In your experience, what grinding disk should I use for this job? I am accustomed to using the grinder more as a cutting tool than a (sanding or grinding tool). When using as a grinder, am I applying pressure to the side of the disk rather than outside edge of the disk like I do when I am cutting something off?

Which edges should be beveled, both the top and bottom outside perimeter edges and the 4 vertical edges that extend between the top and bottom edges?

Would you recommend a very small bevel like 1/8" or something bigger like a 1/4" or more?

Do you recommend using a sealer product after the concrete has cured for a month?

thanks
Tim


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## stadry (Jun 20, 2009)

its easy, mat,,, just imagine you were a drop of water,,, where would YOU go if you were ? if you said ' downhill ', you'd be exactly right :thumbsup:

get a rubbing brick & start rubbing,,, underneath i'd use 4" grinder & 2 1/8" dia blades ( or 1/4" tuck point blade ) to cut in a drip groove,,, its rare water will jump the groove when its underneath :no:

you don't HAVE to bevel 1/4 rnd any of the corners - 'sides, that's usually done by using 1/4 round molding inside the form to save having to do what you've got to do now :furious:

good luck, tim !


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