Would RAS work to feather butt joint drywall

[RonMiller]

I have a basement flood repair job beginning today. The removal/cleanup/mold guys are done and now I'm coming in to hang drywall, add baseboard, and paint.

My question is this: the drywall has been cut a few feet off the floor (as usual in these small flood jobs), so I'll be putting partial sheets up in those places where it was removed. This means I'll be doing a lot of butt joints. I've never liked these since they leave a bulge in the wall and was wondering if anyone had ever tried to use the RAS (or Rotex or ETS) to feather an edge along the butt joint.

I've looked on line quickly to see if anyone had any other ideas about how to do this but found nothing satisfactory.

Anyone done this or have any thoughts?

 

[DKurzweil]

I did something very similar with an angle grinder once.  There was dust everywhere.  Even with a dust extractor hooked up to the ras I wouldn't expect a clean job.  The rotex with some aggressive paper may work with less dust, I have never tried that.

 

[Holzhacker]

Take your drywall knife and run it along the edge of the drywall to cut off a bevel along the edge. Depending on drywall conditions you can get by with doing it either on the new piece only or also on the existing piece. This will help reduce / eliminate the 'bulge'. Beyond that you can flood the seam it a bit with a 12" broad knife instead of just trying to tape it with a 6".
Trying to use a RAS or anything is just complicating the issue.

 

[Tim Sproul]

I've used my 150/5 to sand drywall joints.  I used 120 grit - you might use more or less aggressive grit but do keep in mind that drywall mud typically sands much faster than most hardwoods.  Hooked up with a CT, I had very little dust escape.

I wouldn't want to use the rotex on a vertical surface - a bit heavy and the right angle handle makes it more difficult to keep the pad flat on the wall.

 

[Tinker]

Back when I was taping (a couple of months in winter when too cold for outside work) I used a curved plaster type trowel for those butt joints. Usually at second or third stage of a joint. It was even wider than 12".  I did those butt joints with that and then came back and spread the edges with a twelve inch blade.  That was before the tapers were going to the fast setting compounds of today.  I don't think I could have handled the wide trowel with fast setting compound.

We had a bathroom remodel done a year ago and the painter did three coats of taping in about two hours.  When I was taping, that would have been spread over two or three days.  With the fast set, he did have to do a lot of sanding.  I was expecting a lot of scratching, but his work was really smooth when he was finished.  I was surprised.  

I looked funny working even in those days as I had learned to plaster before sheetrock came along.  As a tool for storing large amounts of compound to slip off smaller amounts with my trowels and knives, I used a big plasterer's "hawk" and piled it high. Today, i see tapers using little, what I call bread trougths hooked to their belts.  So I go back a bit from how it is done today. We used slower setting materials that took hours to set enough to put a second coat on. (When I first started, we used hand mixed compound starting with dry powder out of paper bags.  We put it into 5 gal buckets and added water stirring by hand) Almost no sanding was necessary as we had time to do a very neat job with the "tools".  I almost never had to sand.  Others I watched were even smoother -------- and much faster than I.
Tinker

 

[tiralie]

Take your drywall knife and run it along the edge of the drywall to cut off a bevel along the edge. Depending on drywall conditions you can get by with doing it either on the new piece only or also on the existing piece. This will help reduce / eliminate the 'bulge'. Beyond that you can flood the seam it a bit with a 12" broad knife instead of just trying to tape it with a 6".
Trying to use a RAS or anything is just complicating the issue.

Ageed!
For the really high spots, cut the paper around the buldge strip off and use a drywall rasp to level the plaster to the new board and then tape.
Tim

 

[joraft]

Has anyone used this tool?:

RebateMate

 

[andyman]

no but good idea though especially for using waste

 

[galwaydude18@gmail.com]

Well that is one handy tool if your doing a lot of plasterboarding

 

[RONWEN]

Pretty slick tool John!

 

[Tinker]

That's another one of those, "That's so slick, why didn"t I think of that?"
Tinker

 

[Tom the Remodeler]

If you are worried about not having a beveled edge to hide mud in, you are really better off just ripping out ALL of the drywall on the walls, or at least the bottom 4', and starting over. The paper facing and backing is what gives the material its strength, in the process of sanding a bevel you would be removing the paper facing, greatly diminishing its strength.

Most Pro tapers that I know feather their butt joints WIDE, like 24" to 36" wide, that way the wall has the appearance of being flat, and even if you throw a 6' straight-edge on the wall it will mitigate the humps. The really good tapers I know hate to sand, so after their 3rd coat they are often just using a sanding sponge or  a small sanding block. Can't remember the last time I saw a power tool used to sand drywall compount.
Hope this helps!

 

[gckc117]

I've done that, used the rotex to create a hollowed out area to tape, both on existing seams/cracks that I am patching, and on new patch jobs.  It does work.  Only on small areas, since as others have pointed out there are more effective solutions for a larger joint, or many joints.  Another method if there is to back up the patch area with some sort of nailer, and (assuming it is all 5/8 rock) leave a 4" gap between the old and new, and attach a strip of 1/2" inside.

 

[Tinker]

If you are worried about not having a beveled edge to hide mud in, you are really better off just ripping out ALL of the drywall on the walls, or at least the bottom 4', and starting over. The paper facing and backing is what gives the material its strength, in the process of sanding a bevel you would be removing the paper facing, greatly diminishing its strength.

Most Pro tapers that I know feather their butt joints WIDE, like 24" to 36" wide, that way the wall has the appearance of being flat, and even if you throw a 6' straight-edge on the wall it will mitigate the humps. The really good tapers I know hate to sand, so after their 3rd coat they are often just using a sanding sponge or  a small sanding block. Can't remember the last time I saw a power tool used to sand drywall compount.
Hope this helps!

I've done that, used the rotex to create a hollowed out area to tape, both on existing seams/cracks that I am patching, and on new patch jobs.  It does work.  Only on small areas, since as others have pointed out there are more effective solutions for a larger joint, or many joints.  Another method if there is to back up the patch area with some sort of nailer, and (assuming it is all 5/8 rock) leave a 4" gap between the old and new, and attach a strip of 1/2" inside.

It looked to me that John's tool did save the paper. 
gckc117 method it seems would still leave a but joint to be contended with.

The method of making a very wide feathered joint is the way i learned.  Today, there seem to be a lot of shortcuts.  I haven't taped in nearly 40 years except for my own, or other's family homes.  There are so many new tools available as well as better compounds it boggles the mind.  I do agree with the post that states no good taper wants t sand.  That is the way tapers worked in the past.  When i taped, I always had a little scrap of sand paper hidden away in my tool bag somewhere.  I don't remember having to even look for it, let alone use it.
Tinker

 

[BJM9818]

I usually use the RS/2 for sheetrock.  It's nice and wide and can be agressive when you need to be.

 

[mastercabman]

I use the rotex with no problem.
Hooked up to my vac and no dust.

 

[greenMonster]

Butthanger