Making the tambour door was quite a project. I’ve made them before using a traditional canvas backing to which the slats are glued. I wanted to do something different on this one. As I was thinking about what to do, Rockler happened to send me an ad for their Tambour Router Bit Set.
I ordered them and below is the result as well as some of the difficulties I encountered.
This is an overall view of the tambour. Obviously it’s not installed in the desk yet. That’s coming at a later date. Each slat is 5/8” thick oak and 3/4” wide. The wider bottom rail is 3/4” thick and 1 3/4” wide. Makes sure you finish the slats before assembly! Otherwise the finish will miss spots and may cause things to fuse together. I applied the Danish Oil Natural finish and let it sit for a couple days to make sure everything was totally dry before trying to assemble.
This photo shows the profile of the slats. Notice how each slat interlocks with the previous. The setup of the bits is quite picky so I routed one side of the slats, then switched bits and routed the second side. Make sure to do test cuts first because it’s critical to get the profiles to mesh together. This wasn’t too difficult. I just placed a milled slat against the second bit and lined it up by eye.
Here is a view of the tambour from the end. Notice the tenons on the close end.
Here is a better view of the tenons. Be careful you cut the tenon on the front of the slats. I ruined a couple by not paying attention and accidentally cutting the tenons on the wrong side. For this reason, make sure you make extra slats. I ruined about 6 in the overall process of this project.
What makes this door unlike most tambour doors is that there is no canvas backing. The slats are held in position by the interlock routed into each slat and then steel cables to hold them together. This was the difficult part of the project! Rockler gives no information on this part other than that you should use steel cable. How you attach these cables is not mentioned and I tried many many many things to find something to work. On the end that attaches to the 1 3/4” lift rail, I have a nut that is press fit onto the end of the cable. I own an airplane and have access to my AME (Aviation Mechanical Engineer) and had him use a special tool they use to terminate aircraft cables. It puts a round bolt onto the end of the cable with about 10,000 lbs of pressure so no chance it will come loose. You could also use bicycle brake cable which has a similar attachment on one end when you buy it. The real problem came from securing the other (top) end. Getting the cable at the correct tension and securing it gave me many hours of lost sleep. I tried about 6 different ideas for securing these cables and nothing worked. I finally used Wire Rope Clamps which you can see in the photo below. The cable makes a loop and then is snaked back and forth a couple times inside this clamp to lock it in place. Finally the bolts are secured. Next I attached the loops from two of the cables together with a turnbuckle. I can then use the turnbuckle to adjust the tension on the cables. It works well and the turnbuckles are hidden from view inside the desk when the door is installed.
The turnbuckles and KingChain Wire Rope Clamps came from Home Depot. They also sell aircraft cable but unless you happen to have someone with the hydraulic press to fit a termination nut onto the end, just get a set of brake cables from a bike shop because they have the end termination already attached.
Would I recommend the Rockler Bit Set, absolutely! I love the fact that the tambour bends and flexes so freely yet there is no unsightly canvas showing through and no chance of slats peeling off the canvas. It’s a lot more work than a conventional canvas backed tambour but in my opinion, it’s well worth the effort! The only difficulty I had was the logistics of securing the cables. Now that I have that part resolved, it’s a non issue. I would suggest that Rockler might want to include some information about this in their documentation that comes with the bit set. There may be other better ideas that I didn’t think of.
That’s it for now. Next step is to start some assembly and finish of the desk. I will post the project when it’s completed.
-- Jim in Langley BC Canada --- www.sollows.ca