any tips or trick to doing crown

mattdh

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Apr 10, 2013
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anyone have advise on doing crown? tomorrow i have to do 4 - 2 1/2 ft by 3 1/2 ft boxes in a room (my first run at doing crown). any tips, tricks, or jigs i can pick up that will help me out? i know the kapex would be my best bet but that will be my next purchase after i finish this job (hopefully tomorrow). this wine room that im doing is the whole reason i got in to festools.
 
I am sure that many will be glad to offer tips.  How about telling us what you are going to cut it with and also what you know about cutting and installing crown.  That way we have a starting point.

Peter
 
Sounds like you are mitering it?

I hate working with crown because you are attaching it to something far from perfect. Corners get fat from drywall compound and skew things.  My best results have been with a coped joint and not mitered.

Have a file ready as well so you can file away towards the back.
 
That was another question - to cope or not. Not the greatest at coping big pieces.
 
Once I watched a Youtube video on how to do it it become quite easy.  Just miter it to 45 and then cope it.

 
Check the boxes make sure they are square. If not you will need an angle finder to know what the corner angles are. If they are inside corners, divided the angle by 2, outside corners 180-angle divided by 2.

The table of the saw is the ceiling, the fence is the wall.

You need to find the projection of the crown, this is easily done by squaring a piece of to the fence and table of the saw. Make a mark on the table, run this mark across the entire table of the saw. Install a wide board on this line. It must be wide enough so you do not cut through the board when you cut the crown. This board allows you to nest the crown in the proper position. Remember the table is the ceiling.

Assemble your crown boxes on a table, glue and brad the corners. It helps to relieve the back of the crown with a plane. Slide the boxes up in place, nail them in.

Don't cut/cut off any fingers, don't put a brad into/through your finger, wear safety glasses.

These boxes are so small I would not cope them, pre-assemble.

Tom

 
I like the idea of preassemble.   I checked the corners with a 12" quick square and most were right on if not really close. But I measured the sides of the boxes and and it was weird the corners were 90 but the lengths would be different - like one side of a box would be 38" long and the other side might be 38 3/16" long. (If this makes sense!) if that was the case could the corners be 90?
 
First thing you need to understand is that there are three standard spring angles (38°, 45° and 52°) and when to use which.  If ceilings are below ~9', it looks best to use 38°.  Make your selection based on this and what will look best in a room.  Then look at the Cut-n-Crown to make your cuts really simple and straightforward. 

 
is this a coffered ceiling,   all inside corners?

you should definetly set up some sort of full support crown stop by attaching a 1x board to the table of the saw.. take your time to set it up to match the projection of the crown perfectly. clamp it tight because if this moves your cuts will change

make up a few test pieces (one 3' and one 2' piece)   use these to test fit the corners, you can keep adjusting the miter until you get it perfect

technically, no you cant cut all 90 degree corners on a box with different length sides (if inside corners the short side miter will be open, if outside corners the long side will be open)

this is the good part about coping, it allows you to hide minor imperfections   watch a youtube video (a good one) and take it slow have a sharp fine tooth coping saw/blade and several shapes of files.. it might serve you well however you wont be able to preassemble    when coping, you can also cut your lengths just slightly long and spring them into place making nice tight joints (with miters your lengths have to be dead on)  
to check if you removed the right material from the cope, hold it so you are looking at it straight on, with it in the install position (ceiling edge closer up top and closer to your eyes), you should only be able to see the finish face of the crown and no back material

if you do go with mitered corners, i might suggest looking into getting some 2P10 glue (fastcap)  this stuff is incredibly strong and will allow you to go from assembly to install almost instantly (not having to wait for glue to dry/risk of nail shooting through face of crown    just be aware, it sets up fast!

good luck!

make sure to post some pictures
 
One thing that helped me was making one of each type of cut - inside left, inside right, outside left, outside right and labeling them.  I drilled a hole and tied to a loop of string.  Labelled the top and bottom and wrote the word bottom on the samples upside down.m that way I could concentrate on making the cuts because I was sure that the saw was set correctly.

The other thing I still do is like Tom suggested is set up a board with a stop to control the spring angle, but I also make a back to it - even if it is just as Tallis the crown when sitting on the board.  Your measurements and marks will all be on the top of the crown when placed upside down at the saw.  The cuts made by the saw into the back board will serve as indicators and zero clearance as you line up and make your cuts.

Take your time and most of all have fun.  Crown is counter intuitive and when you do it well pride is spelled PRIDE!

Peter
 
Willy,

There are only 2 spring angle crowns, 45º and 38º. The one crown is referred to as 38/52 (equals 90º). How tall the crown is and spring angle determines projection.

mattdh,

If you have unequal length parallel sides, you cannot have 90º corners at all 4 corners. You can have equal length parallel sides and still not have 90º corners. Check the diagonals, if you have a square they will be equal.

The suggestion of 2P10, is a very good one. If you don't have it, use Tite Bond II, put a little on the cut surface of each piece, rub them together, pull them apart, wait 30 seconds, it will act as a contact cement, just no where near as strong (until it cures). Collins clamps help a lot in this situation also. I still pin the corners.

Tom  
 
One other thing, take a small piece of crown and gauge down from the ceiling. This helps more if your puttiing in individual pieces, but it's nice to know even it your doing the box method.

Tom
 
tjbnwi said:
Willy,

There are only 2 spring angle crowns, 45º and 38º. The one crown is referred to as 38/52 (equals 90º). How tall the crown is and spring angle determines projection.

Tom 

Tom,
    I would respectfully disagree with you on this - the crown that we get around here has a definite top and bottom in the profile when it comes off the shaper.  If it was a simple profile with no difference between top and bottom, I would agree with you 100%.  Look at p. A-22 in the Smoot Lumber moulding catalog I've attached.  You'll note the WM-84 and WM-86 which are reversible, but since it has a 45° spring angle, it doesn't matter.  The more complex profiles on other pages have a definite top and bottom, regardless of spring angle. 

Willy
 
For those reading this thread in the future who are not familiar with the terms the spring angle refers to the angle of the molding projecting (springing) off of the wall.  So a crown with a spring angle of 45 degrees off the wall would have an angle at the ceiling of 45 degree also whereas it is being installed where the ceiling meets the walls at a 90 degree angle.  If the spring angle is 38 degrees the angle at the ceiling is 52 degrees, and so on.

Here is a screen shot showing the appearance differences.

[attachimg=#]

Peter
 
The OP said he was installing today so most of this advice is for other readers.

The first thing I would do is get Gary Katz's DVD on installing crown molding and watch it at least three times.  Then I'd practice a little and watch it again.

Tom's advice on using a continuous crown stop is the way to go.

I make setup blocks that allow me to remove it and reinstall it exactly the same way each time for a particular profile.  

I also make gauge blocks to mark the wall and then pop a chalk line to help set the crown.

The Third Hand telescoping poles from Fastcap make it a lot easier to install long lengths even with a helper.

I only use 2P10 for outside corners.  The gel is so thick it can actually hold the joint apart slightly so I don't use it for stain grade.  I use the activator but you have to be accurate when you put the joint together.

A 23 gauge pin nailer works well for pre-assembled joints.  I really like the Collins spring clamps as well.

I use a Collins coping foot and a sanding stick to finesse the joint.  The Festool RAS is another way to cope but I tend to use it more for scribing work.
 
Here's a jig I use for running Prefinished crown.  There is little room for error when installing white painted crown, and this little bugger is just the ticket.  Like Peter said, it locks in the spring angle and gives you a reference to your measurement line.

Jon

Edit, it's not shown on the saw, but it screws in from the back side of the fence on my dewalt.
 
tjbnwi said:
I've never seen a 52º crown unless it has been installed upside down. It does appear as if the one crown in your link does project on the ceiling farther, if it does, that would be a 52º crown.
 

It's very rare around here to find 52° crown moulding any more due to the lower ceilings in most homes, unlike the 10-12' or higher ceilings that were once prevalent before air conditioning.  I find it mostly in the older homes where the architect wanted to show of his skills by doing detailed crown moulding which was difficult to see if it was installed at 38°, so they flipped the spring angle to 52°.  Go figure... 

 
mattdh said:
anyone have advise on doing crown? tomorrow i have to do 4 - 2 1/2 ft by 3 1/2 ft boxes in a room (my first run at doing crown). any tips, tricks, or jigs i can pick up that will help me out? i know the kapex would be my best bet but that will be my next purchase after i finish this job (hopefully tomorrow). this wine room that im doing is the whole reason i got in to festools.

How did it turn out?
 
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