RedShirtGuy
7th April 2010, 04:18 PM
I've been holding onto this article and plan (http://books.google.com.au/books?id=jvYDAAAAMBAJ&pg=PA56&dq=ding+puzzle&hl=en&ei=SBC8S8XhOYXisQOYyvX2BA&sa=X&oi=book_result&ct=result&resnum=3&ved=0CEcQ6AEwAg#v=onepage&q=ding%20puzzle&f=false) for yonks and now that my table saw has finally been rebuilt it was the first thing I thought I'd have a go at.
I made the jig pretty much the same as the author's except inverted it for use on the table saw as a sled, and instead of using a screwed down lever for the piece holder I thought a beefy little spring would make it much easier to get the cut piece out. I also added an adjustable stop on the front rail for making the straight cuts. I need to put another holder in for the straight cut as I've just been holding the piece down with a stick, which is a bit hairy.
To get the V channel on the right 10 degree angle without a protractor, I marked a straight line 90 degrees from the cut in the sled. Then a few points were marked out along the line. Those points were put through the algorithm (?) distance of point from kerf x tan(10) which gives you the height of the 10 degree line at each of those points. (I double checked with SketchUp too) Those results were marked and connected up to make the reference line for where to stick the edge of the channel.
Yay for having a maths teacher at my disposal :2tsup:
I only used a square Radiata pine stick for the pieces pictured as it needed to be tested and a lot of fiddly adjustments made to the stops, so I ended up wasting a fair bit. I also had to put down a few pieces of tape along the front edge as it was screwed together ever so slightly off from straight. But now that the jig is all good and proper I can stick some better timber in next time and see what kinds of finishes I can put on them.
I made the jig pretty much the same as the author's except inverted it for use on the table saw as a sled, and instead of using a screwed down lever for the piece holder I thought a beefy little spring would make it much easier to get the cut piece out. I also added an adjustable stop on the front rail for making the straight cuts. I need to put another holder in for the straight cut as I've just been holding the piece down with a stick, which is a bit hairy.
To get the V channel on the right 10 degree angle without a protractor, I marked a straight line 90 degrees from the cut in the sled. Then a few points were marked out along the line. Those points were put through the algorithm (?) distance of point from kerf x tan(10) which gives you the height of the 10 degree line at each of those points. (I double checked with SketchUp too) Those results were marked and connected up to make the reference line for where to stick the edge of the channel.
Yay for having a maths teacher at my disposal :2tsup:
I only used a square Radiata pine stick for the pieces pictured as it needed to be tested and a lot of fiddly adjustments made to the stops, so I ended up wasting a fair bit. I also had to put down a few pieces of tape along the front edge as it was screwed together ever so slightly off from straight. But now that the jig is all good and proper I can stick some better timber in next time and see what kinds of finishes I can put on them.