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Taping inside 45 degree angles

5brown1's picture

Anyone have any tips on how to get straight angles. I have a drywall tape which is made for this but my sheet rock joints at the 45s are a long way from perfect. I know a pro would not use it but is there a 45 degree corner trowel made( I use a 90 degree to set corner tape and love it.)?

(post #98659, reply #1 of 13)

I often use a coving tool to mud inside 45's. It is a large flexible rubber spatula I got at a drywall supply. The curved 45 looks really cool, IMO.

(post #98659, reply #8 of 13)

Interesting. I'll have to think about that. How do you handle the base
trim? Thanks

(post #98659, reply #10 of 13)

With the tool I have the radius of the curve can be varied depending on the amount of pressure applied. Light pressure produces a curve with about the same radius as bullnose o/s cornerbead (but concave instead of convex). Then you need a small piece of base cut for the cove. High pressure and the cove is very small and no extra pieces of base are needed (but may need to have the back of the miter shaved a touch to fit the cove).

Coving inside drywall corners is a great look if bullnose o/s corners are being used. It is also good for wall to sloped or vaulted ceiling.

(post #98659, reply #2 of 13)

There is, in fact a 45 o angle bead - we call it 'offangle', metal with paper face. Nice crisp line.

Failing that, just load up one side at a time and allow to dry, then do the other...carefully. Cut a plastic knife/scraper to 45 too, if you must.


***I'm a contractor - but I'm trying to go straight!***


(post #98659, reply #7 of 13)

The drywall supply I went to didn't seem to have anything like that.
The plastic blade might be useful here.

(post #98659, reply #3 of 13)

Straight flex makes a vinyl(?) backed corner bead that you can bend to almost angle without memory. I get mine from a drywall supply house.

Set up a laser with plumb line in the corner, mud, set the bead, wipe,  and continue like any corner.





The awful thing is that beauty is mysterious as well as terrible. God and the devil are fighting there, and the battlefield is the heart of man.
- Fyodor Dostoyevski





The awful thing is that beauty is mysterious as well as terrible. God and the devil are fighting there, and the battlefield is the heart of man.

- Fyodor Dostoyevski

(post #98659, reply #6 of 13)

I got some vinyl bead for the outside corners but the drywall supple didn't seem to have anything like that for the inside ones.

(post #98659, reply #4 of 13)

Our drywall guys use a speical kind of tape for that.  It comes with a built in crease that makes for a straight inside corner of any angle.  Can't remember the name of the product.  It was discussed here a month or so ago.



(post #98659, reply #5 of 13)

I think this is what I have, but my joints are in need of some work prior to placing the tape.

(post #98659, reply #9 of 13)

I never thougth such an acute (sp?) inside angle made any sense, design-wise, impractical to build, not very efficient/useful space.  I ran into one of those in an old house I was remodeling, didn't take long for me to get rid of it and open up the space.  Am I the only one with such weird thinking?

(post #98659, reply #11 of 13)

Reread the post - do you mean 45 or 135 degrees? ie, is it an acute angle, or obtuse? If the former you would have to use "Flexbead", which is 2 thin metal strips on a paper face. Actually, you could use this in any angle. And as a BONUS tip - if there's too large a gap between 2 meeting planes( eg wall/ceiling) rather than premud the joint and wait for it to set up, I just mud Flexbead instead, and carry on normally.


***I'm a contractor - but I'm trying to go straight!***


(post #98659, reply #12 of 13)

As a plasterer, I have a different approach.  You get each wall plane flat.  We snap a verticle chaulk line near the edge on one side and use it as a guide to straighten (flatten) the other side.  Once that side is plastered, we snap a line on the other side and plaster to it.  Though all purpose mud could never go on thick enough to accomplish this, you could use durabond mixed thickly to make up most of the thickness and later finish with regular joint compound.  We often plumb the walls as well.  Skim coat plasterers much like drywall tapers do little to straighten anything.  Veneer plaster works best going on thin and compound is extremely thin.  We often plaster over blueboard with a base coat and then use a lime and gauge finish which can go on heavier than veneer finish plaster.  We plaster in three dimensions, vice two.  In qual;ity construction, it is expected.

One of the plasterers in my crew, looked at a job where a drywall ceiling was coming apart at the seams.  The plasterer told him that a plaster surface was much more durable.  The homeowner argued that the ceiling had been up for 28 years, suggresting that was a long time.  The plasterer said, that was exactly his point. 


(post #98659, reply #13 of 13)

Check the web for 'Trim-Tex' drywall profiles. They have adjustable corners that will make your job a lot easier. Doing those with paper tape will make you want to shoot yourself.