Router Plane

Thursday, June 4, 2020

Wood Body Pinhole Camera - #7 Body Sub-assembly, Assembling the Film Boxes, Milling the Front & Back

Gluing the top of the camera body to the sides is next.  It’s going to be glued up in two steps for the same basic reason as the film box was.  Here is it clamped up with a temporary blank inserted to help keep the pieces square.

Before the bottom gets glued on there are a couple of things to be done to finish it off.  First is to drill 5/64” pilot holes then countersink with a ¼” bit 1/8” deep for the screws that will hold the film box in place.  Once the screw locations are marked on the film box using the small punch (just to the right of the drill circled in red) the pilot hole will get drilled out to 1/8” to provide clearance for the screw threads.  The left photo is a drawing of how it all fits together and the right photo shows the setup for the countersink.

Next is to glue the pin that was turned on the lathe and fitted in Post #5 Starting the Film Knobs into the base.  With that done the bottom is glued on, clamped and left to cure.

After the film box has cured overnight it’s removed from the clamps and using a sheet of 220 sandpaper clamped down to my table saw extension I sanded the faces smooth.

Because one of the two pieces in the corner joints of the film box is end grain and end grain makes a weaker joint, I was concerned about its long-term strength so decided to reinforce it some using pin nails.  Pin nails are shot in using an air gun.  Here is the ½” long one I will be using set against a ruler.   They are quite thin at about 24 thousandths of an inch in diameter.

The pneumatic pin gun, a stick of the nails and the film box look like this.


The next day with the bottom piece’s glue cured the clamps are removed and the joints flattened using the same method as the film box above.  Here it is along with the knobs and film box that’s been marked for the film guide channel.

Moving on the front and back pieces are cut to their final size.  Using the router a rabbit is cut around the perimeter of each so they can be set into the body.  This photo shows the router setup and where the final cut has been made on the ends but not on the top or bottom.

Here it is finished front with the film box opening laid out and center lines drawn in.  They will be used as a double check for locating the center of the pinhole lens since it’s a bad thing when the lens and the film don’t line up.

Milling the mounting flange for the pinhole lens along with the magnet hole for the shutter is next.  It’s not all that hard but does need to be accurately located.  Odds are it’s going to take a lot longer to measure and double check than it is do the milling. 

A little thought needs to go into the order of operations to keep everything concentric and centered in the right place.  First is to drill a small pilot hole all the way through the front.  This will act as my reference point for boring in from each side.  Next is to clamp a stop block to the right side so it will be easy to reset the front in same position as I pick it up and measure the hole depth.  The 1.5” hole is bored from the outside to the proper depth.  Then the 1.5” bit is removed and the 1.25” bit installed.  It is then used to bore the inner opening a little deeper than its actual final depth.  That will make sense in the next step.  Here you can see where that has been done along with the small pilot hole.

The piece is flipped over and the pilot hole is used to align the piece in place.  Now the 1.25” bit is removed and the 1.5” bit put back in the drill press.  The hole is then drilled to the final depth.  Because the inner smaller hole was bored a little deep it overlaps what is being drilled now.  That’s why I didn’t have to worry about getting it to its exact depth.  The photo below shows how it all comes together.

Dry-fitting the pieces together make it look more like a camera than a collection of spare parts.  In the bottom photo the camera is not centered so the pin hole looks out of alignment but it does line up with the center of the film box.

A little work on the back is next.  It needs to have four holes drilled for the magnets that will hold it on and they need to match up with the ones already drilled in the top and bottom.  You can see the holes in the bottom photo above.  After marking them out the centers need to be punched so the drill bit has a starting point and won’t wander.  Since I really want them to match exactly a little help from the jeweler’s magnifier is needed.  It may look a little funny but it sure helps getting it right.

Once marked a trip to the drill press and using a dial caliper to check the depth gets them all drilled square, plumb and the right depth.  Here you can see how they line up with the existing holes in the body.

Next Up – Milling the Shutter, Finishing the Film Box & Glue-up

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