Gyproc Coving Help - non 90 degree corners :'(

[Averroes]

Hi guys, im not new on here I just cannot seem to log on with my old details and my past email address no longer exists.

Nonetheless, I am in a spot of bother. My brother has had two rooms in my parents house re-skimmed. On the face of it they look nice smooth and flush and I proceeded with installing some Artex Gyproc coving. Ive installed this twice before and never had much of a problem but it seems I may have got lucky with good rooms.

I installed one side naturally assuming all major corners are going to be 90 degree or there abouts however ive noticed they are drastically out. in some cases by 15 dgrees. I am using a mitre box however seems useless as I cannot cut anything other than 180 or 45 degree.

I looked at the magic mitre box which was made for this purpose i.e. irregular corners but it is clear they no longer exist and besides you could not cut 127mm coving with them

My question to all the wonderful people is WHAT ON EARTH do i do other than call in a pro as I need to get this done before Sunday and no guys can do so that early.

Ive been told to use a sliding bevel, how and what i do with one I dont know. is there any youtube video, link or any kind member willing to share some knowledge. Im really stuck now guys.

Thank you in advance

 

[Reeves2k2]

What's the position your at at the minute?

Have you stuck any lengths up and mitred any corners in the room in question yet? As this will impact the way to go about it?

It wasn't clear in the op

 

[Averroes]

Hi buddy yes I've put one length on complete and another wall I started

 

[Reeves2k2]

In that case you will probably be better served to scribe the corner

Cut it at 45 as a normal mitre and cut back the opposite way on the back with a coping saw or similar

Try it first with a bit of scrap bit it should get it near enough to be able to run a bit of the adhesive or filler down the joint to make it spot on

The rest of the room mark wall and ceiling at 83mm (if using 127) and where the pencil lines intersect is where you mitres need to be and they will all be spot on

It's hard to describe what I mean if you can make sense of my post it is quite easy once you know what your doing

 

[Averroes]

Hi reeves I think I know what you mean but how do I line up a length in a small area. For example on longer walls its ok since the lengths are 2m. But say the wall is 900mm how do I get both sides cut right without shortening the whole length if I make sense lol.

I tried with a small piece do you need to angle the saw whilst cutting?

 

[roy c]

Get a piece of coving about 500mm hold it into the position it will be in the corner,and strike a pencil line along the outside edge onto the ceiling , then put it into the other corner and strike a line again so the two lines cross, Work from left to right around the room. ,You now have the angle where the two ends of the coving must meet. But it is not so easy to cut them to match. You can use your mitre box to hold the coving ( a good tip is to cut your coving at about 500mm and put a 45 degree cut to take the next piece of coving that is going to but up to the r/side of the coving. Transfer the pencil marks on to the front of the coving and get something that will follow the curve of the coving and draw a pencil line along it. Then put it in the m/box and let the end that you are going to cut hang over the edge of the box (left hand cut will hang over r/h side and vice versa) and cut thru the pencil line, make sure you are holding the coving in the position that it will be on the ceiling. I usually use plasterboard adhesive to put coving up and butter the edges up with a small trowel and push it into position then clean the excess off and sponge.When you are butting the joints together put a bit of adhesive on both surfaces and wipe off excess when pushed together.. I hope you can understand all this (You may have to read thru it a few times to get your head around it )but it has always worked for me, Lets see how the lads do it.... Oh and I have had a few drinks before I put this post on so hope it makes sense I forgot to say what I do is find out what size the coving is when it is fixed to the ceiling (usually 83mm the I put a nail or a pin in the wall at that depth from the ceiling.) and the same the other end of the wall and put a string line thru and put a line of pins along the line to rest the coving on .Do this all around the room before starting and follow the line and not the ceiling, Any discrephences will be on the ceiling not the straight line of the wall..

 

[Reeves2k2]

Hi reeves I think I know what you mean but how do I line up a length in a small area. For example on longer walls its ok since the lengths are 2m. But say the wall is 900mm how do I get both sides cut right without shortening the whole length if I make sense lol.

I tried with a small piece do you need to angle the saw whilst cutting?

Yes cut back 45° or so back into the cove if it's not 100% use a rasp or file to fettle it a bit

On shorter lengths if you use the method of marking the wall and ceiling just cut your piece to length and hold it in position and mark the ceiling edge where the pencil lines cross you then have your angle to cut from the edge of the length to the pencil line
As Roy said use your miter box to hold the piece in the correc position and then cut from the edge to the pencil line do the same on the other length and your angles should match

It does work well and the method can be used on any angle