I'm in the process of building a rolltop desk from scratch all going well except where does the tambor go.?

Repaired a number of antique "C" & "S" roll top desks.

The tambour door rides in continuous grooves in the side panels then over the top of the "pidgeon holes" & straight down between the back panel of the desk & pidgeon holes.

Always the same setup.

Best regards

All tambour has a track, whether it's a separate track or routed into the wood. A lot of tambour goes into a spiral track, but those tend to break or malfuntion more often. U- shaped tracks work best for the longest. And if you're routing it, don't make the corners too sharp or it'll just get stuck. Basically, you need a void big enough for the tambour and track to go across the top and down the back of the desk. You definitely want the tambour to be longer than the area it covers wehn closed, but it doesn't need to fill the whole track and roll up on the floor behind the desk! It will work most smoothly if it's long enough to clear the corners on its route- that is, if you have basically an upside down U, have the tambour get past both turns when it's fully closed as your minimum length. It just works better that way. I can't remember for sure, but I'm pretty sure our old roll top desk had a false back to allow the tambour to go down without being seen. The cubbies and stuff were mounted at the sides... that seems right. I know how the tambour works best, I just don't remember exactly how our old desk was set up.

Many desks and other pieces with a roll top have a spiral shaped slot routed into the sides which allow the tambor to coil up inside. I used to have an entertainment center that did that. Hope this helps.

your track needs to extend into the top and probably down the back when making your track in the back give it as much Radius as you can so your top won't hang up