Trimming an arch top door way

[Bikeboy80]

I have a client with a doorway between two rooms that they want to make the top of it arched. I have framed out for arch top windows plenty in the past but of course the windows have the extension jamb in place and are shipped with the matching interior casing. So now my question is how do I trim this arch from scratch?

The trim will be paint grade. I was thinking of using PVC trim board for the jamb, but what about the casing?

 

[tjbnwi]

http://buyflexonline.com/id1.html

Bendy ply for the upper jamb.

Tom

 

[WarnerConstCo.]

I have a couple forms for gluing up bent laminations from solid wood.

Resaw some 1/8" slabs and glue them up on the form.

Yes, I saw it was paint grade, but I still do it the same way even if it is painted.

 

[Old School Carpenter]

The first question would be what type of casing/ width/ how complex? If its a simple ranch casing, not to bad, a 4" colonial, a little more of a challenge. The easiest solution would be to find someone locally who has a single head moulder capable of producing arched mouldings (i.e. Williams & Hussey). Another option that I did before I had a W&H was to hand scrape the moulding profile after grinding a card scraper to match the profile.
Alot depends on the client/ project also.

Mike

 

[Bikeboy80]

I'm not even sure on the trim profile yet.

This is a project started with a 5-6 week timeline, doing a bit of this and that throughout the house. Clients bought the home back it August and there are lots of things that just aren't up to their standards. (See my recent post in member projects about removing popcorn ceilings) I have been on the job now for three weeks and with all the changes that have been added I would estimate being there for another 5-6 weeks [tongue]

The arch doorway is one of those changes, got the call on Wednesday asking if it could be done and of course my answer is "no problem!"

All of the casing in the house is standard 2 1/4" bead edge colonial. My guess right now is that we would stick with that and put in some plinth blocks.

I had see an idea to rip standard trim into bendable widths, nail and glue them into place around the curve. Has anyone tried this?

Thanks

 

[tjbnwi]

To much lost to the blade to rip and reglue. If it is 2-1/4" trim and you want 1/8" strips, that is 18 pieces. You would loose 9 to the blade. Two pieces ripped to make up for the loss would be difficult at best.

By the way, check to see if it is a bearing wall. If it is a bearing wall, you'll have to move the header up.

Tom

 

[Nick C]

The jamb is not much of a problem. The casing is a different story. This will go a lot easier if the curve is an arc. If it is indeed a circular section, the casing can be milled on a shaper. It's necessary to move the workpiece across the cutter in a circular direction, which requires an auxilliary fence. Take a plywood panel and attach a guide rail--maybe 3/4" x 1-1/2"--curved to the appropriate radius. Stand the panel on its edge, with the apex of the curve at the bottom, aligned with the center point of the cutter. (This assumes the cutter is designed to cut the profile on a vertical face). The idea is to move the workpiece--which has the correct curve but no profile--accross the cutter, guided by the rail. This might also work on a router table, if you can find the appropriate cutter.

 

[Bikeboy80]

To much lost to the blade to rip and reglue. If it is 2-1/4" trim and you want 1/8" strips, that is 18 pieces. You would loose 9 to the blade. Two pieces ripped to make up for the loss would be difficult at best.

By the way, check to see if it is a bearing wall. If it is a bearing wall, you'll have to move the header up.

Tom

That was my worry...

I did open that wall up to check, there is a header but I am not convinced that it is supporting any weight. There is a stud that goes all the way up to the ridge right under a seam in it. The ceiling joists/collar ties run parallel with the wall in question. The wall is 2x6 framing, the "header" is two 2x12 boxed with a 2x6 above and below. I can see daylight between the 2x12 and 2x6s, seems like there is no load on it. I will probably install a new header just to be safe and it will give me good attachment for the roundup framing.

 

[Bikeboy80]

I might go the bendy trim route, though I may contact my window supplier to see if they have casing for a window that is close to the size I need.

 

[tjbnwi]

Your description of the joist direction indicates it is a wall that bears only self weight. The joist are not resting on it. I'd still move the header, you need something to nail to anyways.

There are many bendy profiles, you should be able to find one you can match.

Tom

 

[tjbnwi]

Take your time with the install of the flex trim. There is a learning curve.

Tom

 

[Bikeboy80]

Take your time with the install of the flex trim. There is a learning curve.

Tom

How so? Getting it to follow the radius?

 

[tjbnwi]

Yes. Work from center out.

Tom

 

[Vi_k]

I had see an idea to rip standard trim into bendable widths, nail and glue them into place around the curve. Has anyone tried this?

Thanks

That is what I would do, but you will need 4 pieces per trimmed face. 2 for the left, 2 for the right. Use a bandsaw to rip the trim into 1/8 or so pieces. The reason for 2 pieces per side is kerf waste. Say your piece of casing is broken down into 10 rips. You use pieces 1,3,5,7,9 of the first piece then use piece 2,4,6,8,10 of the other after adjusting for kerf waste. Prepare a glue/fab jig with the proper arc and the glue and nail with 23's.

This is the result after sanding and fitting, these are double sided so 16 pieces were used for the doorway arches.

Good Luck with your project, have a good one,

Vi_k

 

[Bikeboy80]

Nice project!

I actually just ordered bendable trim from a supplier yesterday. The client finally decided to go with standard 2-1/4" bead edge colonial. I was able to order it through my local window supplier prebent to the dimensions I gave them and I can do the fine tuning on site.