Someone asked me to build the 1856 Railroad lock with a clear plastic front. With the clear plastic front piece, one can see how the lock works as you turn the key. It would look something like this, except with a clear plastic front piece:
I thought I had made some permanent patterns to make the 1856 lock, but I searched through my stack of cardboard patterns and could not find any. I made a cardboard pattern by printing out the pieces from Google Sketchup:
Plastic or Acrylic Sheet
I bought the plastic from Mc-Master Carr.........
The plastic came with paper glued to both sides, which I left on. I have read that it is better to scroll saw this material with the paper on versus off. Here is what the 3 sheets looked like:
I used the scroll saw to cut out the middle section of the lock.
Routing the Hasps
Routing the hasps is a scary operation. You use a 3/8" round-over bit to make the top section round versus square. You have to pay close attention not to get your fingers into the router bit. There is also the risk of the hasp exploding when you are routing the top section, which has happened to me a couple of times before.
I tried a newer and hopefully safer method on these hasps. I hot melt glued a piece of scrap pine onto the hasp. I routed it, then separated the 2 pieces using a 1 inch wide chisel. I also used the chisel to scrape away the hot melt glue. This method worked very well!
Cutting the Plastic
I used the cardboard pattern to mark the acrylic sheet. I used a special blade which I read is very good for acrylics.......
I broke the first scroll saw blade, maybe because I had to much tension on it. I backed off the tension a little, and it worked great for sawing the first clear cover.
I went to the drill press and used a 1/2" and 1/4" Forstner bits to drill the keyhole, and both bits worked fine. I scroll sawed out between them.
I highly recommend these Flying Dutchman scroll saw blades for acrylic!!
First Completed Assembly
Although the plastic cut and drilled great, my cover does not perfectly match the outline of the wood middle and back. I can either sand the wood back a little to match, or make a new cover. If I make a new cover, I should glue on the sketchup keyhole first, and make the key hole. Put the cover on, insert the key, then trace out the wood outline. Then scroll saw. This should give an almost perfect match of the OD's of the acrylic and wood.
These locks will be pretty cool looking when they are done!
I need to pick up some Brass screws at Ace Hardware. I'm going to use 4 of them to hold the cover on. The brass screws will add a touch of class to the locks.
I forgot the sequence I used the last time I built 1856 railroad locks. You drill a 1/4" and 1/2" hole in the face piece, then scroll saw out the keyhole. You place the front piece onto the lock, then insert the key. You move the front slightly until the key engages nicely. Then you glue up all 3 pieces of the lock, then saw when done.
I copied this process over to this acrylic lock:
-paste on google sketchup print-out onto the acrylic
-drill 1/4 and 1/2" holes, scroll saw out the keyhole
-scroll saw the outside of the front piece in acrylic
-place front over lock
-move front until key inserts nicely
-trace finished front outline onto front of middle section
-saw middle section and drum sand to the line
-place front plastic piece onto back of lock
-trace upper portion of the wood lock to scroll-saw
-scroll saw upper lower piece, drum sand to the line
This process assures the key fits and the OD of the plastic lines up nicely with the OD of the wood lock.
CAUTION: When drilling the 4 brass screw holes in the plastic piece in the drill press, make sure and apply heavy pressure down on the plastic next to the bit. There is a tendency for the bit to catch when it break through the plastic, causing the plastic to rise up and you make an oblong hole.
2nd Attempt at Making Acrylic Front
Here is acrylic with Sketchup paper print-out glued onto the front:
The keyhole came out much nicer on this 2nd attempt. I next sawed out around the outside of the acrylic. I used this as the pattern to mark the wood portion of the lock with the key inserted for correct alignment.....
Once I sawed the bottom portion of the wood, I flipped it over and marked the top portion for scroll sawing.
I went to Ace Hardware and got 3/4" long number 8 brass screws. I used the pilot bit to drill pilot holes, which is required to keep the screw from stripping. I also put paraffin in the holes as a lubricant.
The lock really looks nice!
All that is left is to route a round-over radius on the back of the lock (using a 1/4" round-over bit) to make it smoother.........then final sanding.
And here is the finished lock............
The acrylic turned out ok to work with. The 1/8" thick pieces worked fine for this application. You do have to hold the acrylic down firmly while you drill the 4 screw holes on the drill press, so it doesn't catch and kick up......making oblong holes.
On future locks of this design, be sure and follow the proper sequence with respect to the key hole and aligning the plastic to the wood lock (see above).
April 2015 Update
Back in August of 2014, a woman searched the net for a padlock for her son. She found my wood padlocks on my woodworking web site athttp://dalemaley.webs.com/1856lockplasticfront.htm
She contacted me by email and asked if I would build her an operating wood lock. I made her a replica of an 1856 railroad lock, except it has a clear plastic cover so you can see how it works.
I shipped it to her mother's house, her mother unpacked it, but did not realize there was a lock and a key in the packing. The key got accidentally thrown away.
She emailed me and I made and shipped her another key.
Recently she contact me again, and said her son played with the lock so much, he wore out the key........and could I make another one! I have made a lot of these locks, but nobody has ever wore out a key before.
I made two more keys. I beefed up the design a little bit too.
The round piece on the end is yellow heart wood from Brazil. The rest of the key is all red oak.
I shipped them out yesterday. Hopefully the child will have many more hours of fun playing with the lock.
November 2018 Update:
I took all my wood toys to the family Thanksgiving supper with 60 people, including 10+ children. They had a ball playing with all my wood toys. Unfortunately, the key broke on the 1856 lock with the clear plastic cover.
This key design is not robust at all. People tend to twist the key too hard, because they don't understand it will work with a minor angle of twist. These keys fail at the top notch, where the wood washer meets the 1/2" dowel...or they break at the notched bottom of the 1/2" dowel.
One way to beef it up, is to use a round 1.375" diameter ball on top. That solves the top of the 1/2" dowel breaking, but not the bottom. Other than increasing the diameter of the dowel at the bottom, the only other fix I can think of is reducing the mating 1/4" dowel in the lock down to maybe just 1/8". Another option is to turn the bottom and 1/2" shaft from 1 piece on the lathe, then carve it down with the Dremel and a 1/2" sanding drum.
Here is a link to the new design with a ball on top.
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