Somewhere on the forum recently I saw a reference to plans for a dimpler in a 1995 Beartracks. Does anyone have that file? I guess I didn't know they went back that far.
thanks
The early years of Beartracks are consolidated into "The Bearhawk Book" that Bob started including with plans somewhere around 800-900. So builders with older numbers refer to the issues by year, while builders with higher numbers would need to look in the book instead. Russ Erb's CD has the early years sorted by issue, and even has a handy linked index by topic.
The Bearhawk dimpler works great.. We put a piece of polished 3/16 plate on top of the channel with a hole drilled in the center the same size as the dimple die shafts. The rod end was drilled on a lathe for the upper die. We had a piece of 3/4" bar and our machinist friend drilled that on the lathe as well for the upper guide. A piece of drill bit was cut for a pin to locate the 3/16 plate die hole exactly where in needed to be with the rod & guide on. The plate was welded & the edges chamfered to transition into the channel so there were no sharp edges. The plate hole then is a good pilot hole for drilling through the channel so the die can go all the way in. It was our solution to get the lower hole exactly in line with the shaft. We added the spring on the shaft with a drill stop but found it less trouble without it the same as the Bearhawk.
We built the throat a couple inches longer than the 23" and radiused the corners of the square tube to the channel with some bondo so it had a nice smooth corner with no welds to catch the edges of the aluminum. The assembly was painted to eliminate the rough steel surfaces. The 1-1/2 in sq tube recommended for the wing jig frame is perfect for the dimpler.
The Bearhawk bucking bar was drilled with a countersink and used to dimple with the dimple rod & die in a couple odd spots where when we could not reach with the dimple tools.
The Bearhawk dimpler works great.. We put a piece of polished 3/16 plate on top of the channel with a hole drilled in the center the same size as the dimple die shafts. The rod end was drilled on a lathe for the upper die. We had a piece of 3/4" bar and our machinist friend drilled that on the lathe as well for the upper guide. A piece of drill bit was cut for a pin to locate the 3/16 plate die hole exactly where in needed to be with the rod & guide on. The plate was welded & the edges chamfered to transition into the channel so there were no sharp edges. The plate hole then is a good pilot hole for drilling through the channel so the die can go all the way in. It was our solution to get the lower hole exactly in line with the shaft. We added the spring on the shaft with a drill stop but found it less trouble without it the same as the Bearhawk. We built the throat a couple inches longer than the 23" and radiused the corners of the square tube to the channel with some bondo so it had a nice smooth corner with no welds to catch the edges of the aluminum. The assembly was painted to eliminate the rough steel surfaces. The 1-1/2 in sq tube recommended for the wing jig frame is perfect for the dimpler. The Bearhawk bucking bar was drilled with a countersink and used to dimple with the dimple rod & die in a couple odd spots where when we could not reach with the dimple tools. Glenn BH727
Mike,
I was away for the last couple weeks. Here are some photos of the dimpler.
I drilled a snug hole in a 2x4 to keep the parts vertical for the weld alignment to get started. The plate welded on the channel was predrilled, located after the shaft guide was welded in place. The shaft was installed with a piece of 3/16" drill bit used to locate the hole then the plate tack welded so that the lower hole is in line with the center of the shaft. This set up made the dies come together nicely. I sanded the rough mill scale, added some Bondo to make it smooth & gave it a coat of Yellow rust paint. The main thing is to remove any sharp corners or roughness that may mark the aluminum.
I used the 3/16" plate with the thought that it was easier to set the predrilled hole to the center of the shaft. The shaft is removed & then the plate pilot is extended through the channel for the dimple die.
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