Opinion Wanted -- Cutting a Running Splice on Crown Molding

[George Bokros]

I need to do a running splice on crown molding.

Option #1Cut it upside down like cutting a corner miter. From what I have seen and found on line it is usually done this way.

Option #2 Cut held flat against the fence. I know it can be done this way and the joint will fit and work.

Would you find it odd or objectionable to use option #2.

I am cutting my joints using a combination bevel and miter setting and cutting the joints flat on the saw table so I do not hold the crown upside down and backwards.

Thanks

[Mel Fulks]

I prefer the simple butt joint for painted work. And a little sanding and filling will make it disappear. On stained work it's
sometimes possible to get better result with angled splice.

[Robert Engel]

George,

This guy (https://www.youtube.com/watch?v=LaJTC5kRhkI) has a very good video on this procedure. Worth a look.

[George Bokros]

George,

This guy (https://www.youtube.com/watch?v=LaJTC5kRhkI) has a very good video on this procedure. Worth a look.

I like his 22.5* cut but his sanding and filling will not work for pre-finished stained crown molding.

[Mark Wooden]

+1 with Mel on the butt joint. I usually will glue in one or two bisquits for alignment and to keep things in place.
Butt joints are the smallest
Butt joints don't look as bad when the finish or paint cracks over time
Butt joints are easiest to cut, join and sand
I have had to join three pieces of crown (even more in long hallways) in large rooms on more than a few occasions over the years. We would always look to center the joints over or between doors, windows or panels so they looked like they belonged there. Or, space the joints at ratio spacing ie: 3-5-3 or similar to keep things more pleasing to the eye.

IMO, mitered splices aren't worth the trouble, YMMV

[peter gagliardi]

Butt joints, and straight bevels are generally used in lower class work. The reason most people don't miter as described, is that it takes time and effort to make it seamless.
In 31 years, and a few miles of crown mold installing, I have yet to use a butt or straight bevel joint.
I have however been in many places- commercial and residential, and seen the poor results from doing so. Either in initial fitting, or shrinkage over length- don't ever believe the lie that wood doesn't shrink in length.
Just my .02

[George Bokros]

How do you think this would work. Since my miter saw is a compound miter saw tip the blade to 45*, set the miter to 22.5* and cut the scarf joint with the crown flat on the the table of the saw.

[Mel Fulks]

I've seen them done that way ,but they often end up a little misaligned. Honestly ,with the material being stained it just doesn't show slight flaws the way paint does. Trust your own eye

[Darcy Warner]

width shrinks, not length.

[johnny means]

width shrinks, not length.

No wood moves in all dimensions. It just moves much less along the length. A butt joint in the middle of a 20' length of crown will eventually become a gap. I was taught to use a scarf joint when applying tell and molding. That way any shrinkage or separation only creates a slight reveal rather than an open gap.

[Ken Grant]

It depends on the size of the crown. If it is smaller-say less then 4" tall, I would just do a straight bevel and glue it.

If it is bigger crown and you are worried about the joint, you can reinforce it any number of ways-for overkill I personally like to do a butt joint and put in some pockethole screws to pull it tight, then glue and nail a piece of wood on the backside. Then you can cut and install it like one long piece of crown.

If posslble, bevel the joint away from where people will be most likely to look at it from in the room.

[Darcy Warner]

No wood moves in all dimensions. It just moves much less along the length. A butt joint in the middle of a 20' length of crown will eventually become a gap. I was taught to use a scarf joint when applying tell and molding. That way any shrinkage or separation only creates a slight reveal rather than an open gap.


which is why a sprung in place butt joint is better than any scarf joint. A house will move more than the trim from season to season.

[Wayne Lomman]

Pete and Johnny are on the money. Even if we can't get our heads around why, a mitred joint works and butt joints don't over time. Springing in place is risky depending on the season when you do it. Cheers

[peter gagliardi]

Scarf joints are made the same way as outside miters- upside down, nested to fence, and miter angle at 45 degrees.
Anybody that thinks wood doesn't move in length, obviously doesn't have much experience, but if they are paying attention, eventually they will. :rolleyes:

[Darcy Warner]

Sure thing. Never installed any trim anywhere.

scarf joints end up looking like poo.

Sprung in place but joints with a bit of glue don't go anywhere.

No different than sprung in place coped runs of crown.



but whatwver.

[Robert Engel]

George,

Even with stained wood, I think the principle of glueing and using a backer as he demonstrates would be useful. Joining before installation is good idea, too. I agree a 22.5° scarf joint has better glueing surface.

Darcy,

Typical IME crown moulding wood will not move enough lengthwise to cause a gap. Took me a while but I've learned all moulding joints must absolutely be glued, not simply filled or even if tight, expect paint to do the trick. What I've found is over time the paint or filler will shrink, giving the appearance of the joint opening up. Settling and improper nailing can also cause problems down the road.

For crown, I think installing nailer boards is a good consideration.

[Mark Wooden]

Butt joints, and straight bevels are generally used in lower class work.
Just my .02

Peter, when you look down your nose at us, all we see is your boogers.
After more miles and years than you, I can pretty much see you didn't recognize a good splice when you saw one.

[Ole Anderson]

A pro buddy did my crown molding for me. He did a 45 degree splice on my one long run in the living room. It opened up about an 1/16" a year later. Amazing what a little painter's caulk can do...

[George Bokros]

A pro buddy did my crown molding for me. He did a 45 degree splice on my one long run in the living room. It opened up about an 1/16" a year later. Amazing what a little painter's caulk can do...

Works good if it is painted crown, mine is stained.

[peter gagliardi]

Peter, when you look down your nose at us, all we see is your boogers.
After more miles and years than you, I can pretty much see you didn't recognize a good splice when you saw one.

Mark, you are mistaken, sorry you took it this way. I wasn't looking down my nose at anybody.

I do however stand by my assertion that a butt joint is, was, and forever will be considered acceptable in "lower class work"- I get this from extensive reading and research of old texts while learning what I can of different levels and classes of work over the last few centuries.

I do not have the text in front of me, but this is not an idea that I originated, even if I choose to agree.

[Darcy Warner]

Every old house from Greek revival through high Victorian Era normally has butted joints. They still look good to this day.

Glue, a backer, a dowel, a biscuit, a domino, etc every butt joint done properly has looked better long term than any scarf joint I have seen.

[Mel Fulks]

I think some of the admonitions in old books have timed out. Don't think the authors would have thought much of "brick veneer " single thickness walls ....but they are catching on! In really early work some of the trim was thick and structural.

[Martin Wasner]

Uhhhh, why aren't you putting some spring in your scarf joints? You nail the one to the wall, and roll the other one behind it. Good luck on a short one, but long pieces is a cake walk.

I do 30º scarf joints. Why? I don't know.. I can't think of the bevel/angle numbers off hand.

[Jim Dwight]

Ron Paulk has a great series of youtube videos on crown molding. I am not saying he is better than people on this website but for those of us who are not extensively experienced, his tips are useful. I believe he makes joints cut at 45 degrees with the back of the crown flat on his Kapek. I haven't succumbed to the green cool aid but I also cut it flat at a 45 bevel. Ron also staples and glues a backer across the joint and I copied that too. I installed several rooms of crown before seeing his videos. I didn't use a backer, the joints opened.