November 13, 2009

Auxilliary Fence

photo copyright Karin Corbin 2009

I did not find any C shaped brass channel of the size I needed on my shopping trip to the stores. However I did find some square tubing that could be made into C channel. 

Brass is somewhat dangerous to cut and drill. It is soft and the bits of material being cut will bind up in the drill  flutes and saw and even clog up your files. Because it will grab and bind on the tools it can spin out of your control and damage the part and you.

Working with small pieces of any type of material requires being able to control the material so it does not move in directions you don't desire. For this particular operation I created a purpose made auxiliary fence. Nothing special about making it just a piece of scrap plywood with a notch cut into it that I sized to fit snuggly around the brass tube I wanted to trim.

I clamped that purpose made fence to my normal table saw fence and from the back I pushed the brass into the saw blade. When I had a long enough cut (less than an inch) I pulled back on the brass tube to pull the piece back out of the saw blade instead of trying to push it on through. I don't need long lengths for my parts. If I had to cut long lengths I would need to make a second auxilary fence that was clamped behind, but clear of the saw blade. A long skinny length of material tends to whip around and lash back into the saw blade and of course knocking into the teeth on the saw blade would ruin the part.

In the photo below you can see the backside of the auxiliary fence and the cut I made into the brass tubing. It is a very simple cutting task but a potentially dangerous one for injury to hands and fingers.
photo copyright Karin Corbin 2009

I will do any filing and drilling work to this piece before I separate my new C channel from the long length of brass tubing. It is good to have a nice built in handle. I will also use that advantage to clamp the piece to my drill press table so it does not spin out of control. This channel will hopefully become part of a catch for my window locking system. My reference book "The French Farmhouse" calls the type of latch an "espagnolette". I will be making a very basic, no frills version, of that locking bar system.

Creating holding fixtures so you can work with small pieces of materials is a skill dollhouse builders must develop. If you needed to modify a small piece of commercial, strip, basswood and safely run it through a saw or router you can use the same type of technique of making an auxiliary fence that I used to resize my brass tubing.

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