The way to get a gapless fit against a wall is to scribe the end/edge of the wood to the actual part of the wall against which the wood will sit.

However, many times a small gap---when using dark stains--- virtually disappears when the stain is used on the ends of the trim. That can evem work on a scarf joint---the angled joint used when mating two pieces of trim to increase the length.

Now to those steps----

1. Sand---using no more than 150 grit paper. That is sufficient to get the wood smooth and still allow good stain penetration.

2. Stain---wipe the stain on with a rag---that allows you to better control the color.

3. Lightly sand(by hand) with 220 grit paper. That will smooth the nubs raised by the stain without removing stain.

4. Poly Finish or varnish. Varnish will be much easier to repair than a poly finish.

5. Install

6. Fill Nail Holes with color-matched wax crayon.

The bowing is not really a big problem. Twisting is much more serious. I have installed narrow trim that bowed both ways without a problem---the nails hold it in place. Twisted trim usually will not lay flat regardless of how many nails.

Handymac, very clear advice. Thank you.

I guess the one area I am most concerned with is the one side of the jamb that can be seen directly from the side as it touches the wall. We have our foyer and then immediately to the left is the double wide entrance we are trimming out. If you stand in the foyer and turn your head to the left you will be facing directly into that side, not the face front of the jamb, but the edge as it meets the wall.

We have a slapped together 60s track home and the consistent thing we find is the wonkiness of the framing. The framing of this double doorway has it where the top plate is askew of the stud by 3/8s to one side, making the alignment of the trim off. So I fear looking at a big gap there, and I'm not sure how scribing in that situation will help - even though it is great advice for other areas.

Also, really quick. When wiping on the stain, is it best, or does it matter, to immediately wipe off and do multiple "thin" applications of stain, instead of trying to get a deeper color all at once?

Gosh. Sure appreciate this help in a pinch!

For doing that end, just start with that end---simply back cut the end(make a 30 degree bevel to the back side of the trim. Then you can use a small file to shape the end so it matches precisely to the wall.

How the stain is wiped on and how long it is left versus more than one coat really depends on the wood, the stain, and the kind of rag/cloth used to apply. The beauty of using a wipe on method is that it almost alyays is lighter than simply brushing/setting stain, so you can do a lot of experimenting.

I was thinking about my last afvice and detected a gotcha.

If you back cut the trim, you can file it to fit the wall, but there will be a gap left at the top/bottom due to the back cut angle.

So, back to the scribe advice. Simply use a common compass(school type. Set the distance between the metal point and the pencil point at ab 1/2". Place the trim where it will be mounted and folloe the door frame with the compass. Cut the trim on the line drawn by the pencil---leaving the pencil line. Then use a file(wood rasp) or a sander to finish the end to match the door frame. Then make whatever cut(corner or scarf joint) needed on the other end.

Okay, that is brilliant. Scribing it THAT way. I think I get that now. More importantly, DH might even, too. We did some scribing just last week with a built-in, and bought the compass just for that purpose.

He shaved a bit of the drywall down at the high points for the doorway. Hopefully that will help us out, to begin with. And then your scribing tip - we may be trimming pretty.

Thank you.

Happy to help.

I haven't done the door jambs/walls yet in my cased opening, but have had to skim out walls (built-up corners) to get baseboard to lie flat, and have had to cut sheetrock to get window casings and prehung door casings flat. If the sheetrock sticks out past the jamb, cut it with a razor and fill a syringe with latex caulk to fil the fine line, I haven't even bothered to paint b/c have only had to do this on navajo white walls so far, and only on top of the casings where no one sees unless they're 7 ft tall. Where my jambs stick out past the sheetrock, I have to skim a few coats (had to do 7 coats in one place for baseboard, had a huge gap!) to build the wall up flush with the jamb, then paint, then install. I hate finishing in place - better to join up the casing with biscuits and once it's dry, remove the clamps and finish, then you can put it up, corners stay tight,faces are flush, all you have to do is fill nail holes. I like the putty in can better than the crayons - you can mix different colors to get exact match for your stain.

I just removed wallpaper but whoever hung wall paper took off all stained trim hung it to floor and rehung trim so there's ton of nails holding it in so he wanted me to cut old wallpaper close to stained trim looks like s___ in the parts that has gaps u can see old paper it's walnut stained trim not painting trim so what to do about gaps I think caulking might be only way to make it look half way decent help