The prototype ceiling mount took 4 hours to make, but like each part of this project, the prototypes are implementations of ideas and often involve experimenting with how to put the piece together and how to get the geometry correct. I always have the design either on paper or in my head before starting the prototype but I often find that I haven’t thought of some little thing so I have to improvise to get the final prototype. I then think about how to build the production run more efficiently, and sometimes make a second prototype. This is what I did for the ceiling mounts.
So, after thinking about the first and second prototype, I devised a means to produce the ceiling mounts in a production form that would be as efficient as I could make it. This entry details the process for making the ceiling mounts.
The first step is to cut the raw lumber (1×2 Red Oak stock into 7.5 inch sections. The picture below shows the cut wood for 40 ceiling mounts (80 pieces) plus one piece just in case I mess one of the pieces up.
Once the raw stock is cut to length, I sanded it lightly to make sure all sides were flat and to glean off the rough ends. I stacked the raw stock next to my routing table. The router is set up with a detailed bit as shown in the previous posts with the prototypes. Below is a picture of the stock on the left before processing with the router.
During the routing process, I accidentally flipped one piece over and routed the wrong side so that was my one extra piece. So, throughout the rest of the process, I used that piece for test before starting the step. I discovered that the hose to my shop vac fit perfectly to the hole on the back of the fence for the routing table. Previously I did not use the fence because it has a spring loaded guard that gets in the way when routing the end of the wood. But, the vacuum was very nice for keeping the dust down.
Routing each piece was a bit easier with the fence. Without the fence, when I got to the end of the wood, the would would catch on the rough fibers and would kick sideways which would sometimes cause a nick. But, with the fence, I could run the board to the end without a hickup. After doing both sides of the board, I would then do the ends and put into a pile on my right. The picture below shows the stock for the ceiling mounts after applying the detail.
During the prototype phase, I found that you have to route the wood before you drill the holes for the dowels that connect the two pieces. If you drill first, the wood will be weak on the ends and will splinter near the holes. Yea, that is logical, but I still tried it because it is easier to mark the holes for the drill before routing.
So, after routing all of the stock for the ceiling mounts, I stacked it near the drill. I then used my little jig that I made earlier when I thought I was going to use dowels to hold the curves together and for using as a stop on the miter saw. By using a clamp and setting the jig in the right location, I could do all 4 holes in the stock and get the product to have perfect symmetry. I start with the routed side up, drill a hole, flip the board over, drill the second hole, flip the stock over so the routed side is up again and turn around, drill another hole, flip the stock, and drill the fourth hole. I don’t know why I didn’t think of this when doing the prototypes.
After drilling the end holes that would be used to receive the dowels that connect the pieces, I separated the stock into two piles. One would be for the top pieces and the other for the bottom pieces. The top piece needs a 1/8 inch hole with a 3/8 inch countersink hole half way through the stock exactly 1.75 inches from the edge and dead center in the stock. The holes will be used to receive screws to mount to the ceiling and the 3/8 inch countersink hole will be filled with a 3/8 inch mushroom cap. The bottom needs a 5/32 inch hole with a 1/4 inch countersink hold half way through the stock at exactly 2.25 inches from the edge. The holes in the bottom will be used to accept #4 aluminum screws that will mate up with the track to mount the track to the ceiling mount. Each hole will be filled with a 1/4 inch mushroom cap. The reason that the holes for the caps in the bottom piece are smaller than the top piece is due to the visual impact of the caps with relation to the distance between them.
Below is a picture of the drill press with the little wood jig that I made. Notice the the jig has a nook for receiving the stock with a long side to keep it flat and it also has another piece of wood on the other side so that I can use the jig as a stop for the miter saw.
After drilling all of the holes, I sanded every side of the stock with a fine sanding belt on the table sander. This took the little burrs off of the edges of the wood where the router bit and drill bit touched the wood. The result is a very soft feeling piece of wood. Below is a picture of the two sets of finished product. The left side is the stack of top pieces, and the right side is the stack of bottom pieces.
The last step in creating the parts for the ceiling mounts is to cut the dowels to length. When doing the prototypes, I cut the dowels with a hack saw. But, for the production run, that would have taken forever and it resulted in uneven lengths. So, for this run, I used my little jig to be a stop on the miter saw and cut all of the 54 dowels into 1 foot sections. Actually, each dowel is short by 1/8 inch which is the thickness of the saw blade. I have plenty of clearance for the tallest car so this little bit won’t matter. What does matter is that every dowel is exactly the same length.
One little problem that I run into with the dowels is that Lowes (and Home Depot) put their computer SKU tag on the dowel on the end by wrapping it around the dowel. The tag is difficult to get off and it leaves a sticky side on the wood that gums up sanding belts and also prevents the wood from taking stain or finish. So, I separated the ones with labels into a different pile (in picture below on top of right group of stock in the picture below). I then peeled off each little sticker, then rubbed with vinegar, let sit for about 2 minutes, then rubbed with dish soap and water. The gum didn’t completely come off, but what didn’t come off isn’t very sticky at all. So, I then took the dowels down to the sanding belt and held the dowel so that the full length of the dowel was on the belt parallel to the direction of the belt movement and I quickly rolled the dowel back and forth so as not to produce a flat spot. The remainder of the glue came off, partly on the belt, but did not create gummy areas on the belt. Below is a picture of all of the pieces (except the mushroom caps) necessary to build the ceiling mounts.
The remaining work to be done is to sand 3/4 inch of the ends dowels down just a millimeter so that they will fit snugly into the holes of the stock. This little sanding bit is necessary because the holes are 5/16 and the dowels are 5/16 so the fit is to tight to reliably be able to put the dowels in with glue and have time to position them. If you don’t sand, within a few seconds of putting the dowel in the hole with glue, you cannot turn it, pull it out, or push it in further. So, taking a little off of the dowel gives you time to work on adjusting the position in the stock.