Earlier this year I purchased a used Delta drill press. After I got it home I found that the set ring which holds the depth stop was cracked. The original part is cast iron and subject to break if it is over tightened. It's an older model Delta and I was not able to find a replacement part. It's not a complicated part and I decided to make one.
My first attempt was out of solid surface counter top (e.g., Corian). I've used that for a lot of things. It's a super hard plastic that is almost indestructible -- almost. In this case it cracked when I tightened the bolts to get a snug fit.
Next up for replacement material was aluminum. I ordered a 3/4" thick bar (same thickness as the original part) and set to work. This is where my new respect for this material was gained. I've worked thinner aluminum stock using regular wood-working materials. One of the challenges of working aluminum is that it clogs up your tools. It simply fuses into spaces -- like the gullet between the teeth of saw blades and files. You have to clean these frequently.
I tried a variety of approaches. Using a hole saw produced a high-pitched noise in the range that causes my wife to leave the state, and didn't really cut. A sabre saw with bi-metal blade was also no good. It cut better, but was horribly slow and I spent more time keeping the teeth clear than in use. Did I mention this aluminum was 3/4" thick?
What finally worked was a combination of drill, hacksaw, router and elbow grease. I drilled out most of the hole and then used a hacksaw to remove material as close to the final shape as I could. Using double-sided tape to hold a template in place I removed the rest with a flush-trim router bit in multiple passes, about 1/8" at a time. It took most of the afternoon to get to the final part (Did I mention the aluminum was 3/4" thick?).
I smoothed all the edges using spindle and orbital sanders. Along the way I drilled and tapped the holes. I'm pleased with the final results -- better than the original part in some ways.
New and old part along with aluminum bar from which it all began.
Part installed and ready to use.
One very messy shop floor. Those are flakes of aluminum.
My first attempt was out of solid surface counter top (e.g., Corian). I've used that for a lot of things. It's a super hard plastic that is almost indestructible -- almost. In this case it cracked when I tightened the bolts to get a snug fit.
Next up for replacement material was aluminum. I ordered a 3/4" thick bar (same thickness as the original part) and set to work. This is where my new respect for this material was gained. I've worked thinner aluminum stock using regular wood-working materials. One of the challenges of working aluminum is that it clogs up your tools. It simply fuses into spaces -- like the gullet between the teeth of saw blades and files. You have to clean these frequently.
I tried a variety of approaches. Using a hole saw produced a high-pitched noise in the range that causes my wife to leave the state, and didn't really cut. A sabre saw with bi-metal blade was also no good. It cut better, but was horribly slow and I spent more time keeping the teeth clear than in use. Did I mention this aluminum was 3/4" thick?
What finally worked was a combination of drill, hacksaw, router and elbow grease. I drilled out most of the hole and then used a hacksaw to remove material as close to the final shape as I could. Using double-sided tape to hold a template in place I removed the rest with a flush-trim router bit in multiple passes, about 1/8" at a time. It took most of the afternoon to get to the final part (Did I mention the aluminum was 3/4" thick?).
I smoothed all the edges using spindle and orbital sanders. Along the way I drilled and tapped the holes. I'm pleased with the final results -- better than the original part in some ways.
New and old part along with aluminum bar from which it all began.
Part installed and ready to use.
One very messy shop floor. Those are flakes of aluminum.