[dfphoto]

Hi bought a bi-metal and carbide 4" hole saw for a dryer vent in a condo. I went through 2" of wood then hit the roof paper vapor barrier. I changed to a carbide bit and drilled a 1/2" quickly then it seemed to stop cutting. I tried running on the hammer setting of my drill but that allowed only another 1/8". I thought something was wrong, but I've never used a hole saw in stucco. I see inside the wall that I'm still in cement/stucco, anyone have any ideas?

Here are some pics. first is the carbide bit the second is the hole sorry it's a bit odd looking the outer material was 2" wood then a ligher colored cement like material as you can see the pilot hole and the material I cut how ever if you look at the groove it almost looks like there is a mesh wire but can't tell if it is that or the grooves from the blade.

 

[Windows on Wash]

Drill the remainder of the center hole all the way through to the exterior.

From the outside surface, use a diamond/concrete cutting hole saw to finish the cut from outside to inside. The center hole should help located you on the right spot and keep it centered.

 

[joecaption]

A 4" pipe is not going to fit correctly in a 4" hole, should have been using a 4-1/4" for a vent pipe.
Look on the back side of the outside vent, most have a lip where the pipe slides in that will not sit flush on the wall unless the hole is over size.

 

[Bud9051]

Not that familiar, but if Joe is correct, moving to the outside might be the best time to switch to the larger size. May only need to come in the depth of the lip. Just guessing.

Bud

 

[dfphoto]

Hi guys, thanks for the tip, I found out Lowes gave me the wrong arbor twice, none had a carbide tip, hoping that will make a difference. I also checked the hole with the duct and it fit so even though it says 4" it must be 4 and 1/8".

I am a little scared so I hope this works going there in one hour.

 

[Canarywood1]

That mesh wire your talking about may be expanded mesh lath for the stucco.

 

[dfphoto]

Hi guys success!!!!

I did what you said and tried the pilot hole took about 5 sec. then outside I cut through in about 10 sec.

Once I had a minute I looked and you're right after the 1/2" I mentioned in the scratch coat there was 1/8" and then some thick wire. I guess I actually cut through that with the hammer function and had I kept going another minute I would have been done.

Anyway, lesson learned...spyderproducts called this morning and they actually are sending a replacement arbor and cup so that's pretty cool. It was only 33.00 for both in Torrance Ca. not sure if that's normal but that's pretty cheap for an arbor and carbide the bi-metal was 13.00 thats in 4-2016 prices...

So now on to drywall after I got the vent wired up and vented out... pretty excited... Thank you to all who posted I really needed a boost and a little comfort. I really love this site, all of you are great and wish we could all have a beer or burger together. Thanks again, Dave