I have never tried to make birch take stain like mahogany, but I have stained poplar to look like mahogany. I can tell you what I did, and some of what I did may apply to you. I think you'll easily succeed, given that you had the grit to paint such a small space with oil paint successfully :-) It looks fantastic by the way.

Step 1: Washcoat (google this and there is lots of good reading on the hows and whys). Basically makes the wood take the stain more evenly. Waaaay better than using minwax wood stain conditioner, which has a short working time. This stuff, you brush on, let dry, and can take your time proceeding to the next step. I used Pro finisher by Parks universal sealer mixed with 2 parts denatured alcohol. Basically any suspension of dewaxed shellac and denat. alcohol in the right proportions will do. Wait 45 minutes before proceeding.

Step 2: Use a coat of very light-colored stain to fill the pores in the wood and begin layering on color. I used minwax cherrywood gel, but you can use whatever you want. Many pros start with dye at this point, but I could not find it readily available at consumer outlets, so I just used a light stain in a color that established the undertones in the wood that I wanted. Layering on color like this is much more forgiving than trying to achieve the color you want in a single step. Also, poplar has pores which tend to turn black with most stains; this step filled those pores so that I did not get the look of thousands of tiny black lines, which in this case, I did not want. I rubbed the stain on with a small cloth, then wiped off after a minute or less. Your door is big, so I'd work quickly. Wait the recommended drying time (usually 8 hours) and then some before proceeding, or your colors will dissolve and mix into each other, leaving lighter patches.

Step 3: Establish the main color. This is the fun step where you start to see where you're getting. In my case, I mixed 60% minwax aged oak gel and 40% mahogany, plus a dab of walnut. Apply as in last step, wiping off after just a couple of minutes, so that the stain does not have time to dissolve and "lift" the previous coat. Wait the recommended drying time again (usually 8 hours).

Step 4: Seal coat. This step is necessary to prepare for step 5, which is the "toner" step (again, googling will turn up more reading on using toner in a staining process). This time, use undiluted sealer (the same one used with denatured alcohol in step 2). Apply a thin, even coat and wait 45 minutes before proceeding.

Steps 5 and onwards: This is the fun part. You are getting close to home. Toner is basically a tinted polyurethane that simultaneously protects your wood finish, and builds on layers of color. Again, the pros custom mix their own; I just used minwax polyshades antique walnut. I did two coats to achieve the look I wanted. Your mileage may vary.

By layering on color like this, you get an even, rich finish with good depth, and you are able to fine-tune to get the color you want. This process may not be for you, and I have to admit, in trying to match the rest of the woodwork in my house, I tried about 64 different combinations (varying color at each step multiplied my possibilities quickly) and owned just about every minwax color out there, but I am extremely happy with the results, and multistep staining is so much more FORGIVING than a two-step process, I am hooked.

I must give credit to Paul Snyder, on whose article below I based my work. I hope you take a look, as his pictures are worth a thousand words, and his process is also recommended for birch

Best of luck with your project!

Here is a link that might be useful: Staining difficult woods

Well...to correct a mis-impression...I didn't PAINT with oil...I had to sand the existing oil so the latex primer would hold. Every flippin' inch of that room. Thanks for the compliment on the paint choice/job. I HAVE painted little spaces like that with oil...I painted the entire interior of our former home in oil about 20 years ago. (It was an older home and I wanted to seal in any potential lead.) I was much younger then.

Wow...your process sounds really involved...and potentially enjoyable. And you sound like you are as much of a perfectionist as I am. I've actually hired a handyman/painter guy to do the job for me...I'll discuss your process on with him.

I also have some calls in to places that MIGHT be able to help me find a mahogany luan door. Which would be the best solution. Keep your fingers crossed!

melanie

Update on the door...

Found out that my local full-service lumberyard could make the door I found in the attic fit...they will cut it, re-glue the stile, and have it ready by tomorrow afternoon...for $50. Best of all...it will match.

Life is good.

Wow that's fantastic news! I'm glad someone was thoughtful enough to stick that door up in the attic instead of out on the curb. Wish the po's had been that thoughtful at my house!

If anyone else reading knows how to make poplar look like mahogany in fewer steps, please drop me a line :-)