Tom Martin
Well Known Member
I like to try different things on new projects and noticed that Cleveland tools now has a substructure dimple die set. I have noted in the past that sometimes dimples do not seem to nest properly, leaving an ever so slight gap between the parts. Thousands have airplanes have been built using just one set of dimple dies but I thought i would give it a try and so I ordered a new set of standard, and substructure set.
In use the parts do nest nicely together although what you see in the finished product is fine with or without the substructure dies. What I did notice is that the hole size increased with the substructure dies. I have a set of Avery dies and did a quick test of the three dies.
"A" stands for Avery
"CS" stands for Cleveland Sub Structure
"C" stands for Cleveland standard dies
All dies are for 3/32 rivets (the small ones)
(In the picture the Avery hole looks bigger but that had to do with camera angle, note the smaller crisper look of the Avery dimple)
I used number drills to test the hole size
A Van's RV14 prepunched hole, right out of the box, will accept a #38 drill (.1015")
A normal Avery die produced a hole #37 (.1040")
A normal Cleveland die hole size the same #37 bit
A Substructure Cleveland die will accept a #34 drill (.1110")
Thus the hole size is 7 thou larger using the Substructure die. It works except that hole now takes a bit more rivet to fill it and any larger hole can be more difficult to rivet. What is more worrisome is that when used thicker material, 40 thou for example, the same as is used for the rear wing spar, I could see some small stress risers around the edge of the dimple hole. This was not evident on the thinner rib material.
Both the Avery and Cleveland normal dies produce a nice final product. The differences are purely up to the individual as to what looks better. The Avery die actually produces a crisper final hole with the outside of the dimple measuring 0.220" vs. and O.D. of Cleveland at 0.230".
As for myself I am not going to continue using the Substructure dies as I see no real visual improvement to the final product and there the two issues of increased hole size and subsequent stress risers on thicker material. The larger hole size was seen when used on thick or thin material.
I would suggest if you really feel the need for a substructure die use the cleveland die and nest an Avery die within it.
In use the parts do nest nicely together although what you see in the finished product is fine with or without the substructure dies. What I did notice is that the hole size increased with the substructure dies. I have a set of Avery dies and did a quick test of the three dies.
"A" stands for Avery
"CS" stands for Cleveland Sub Structure
"C" stands for Cleveland standard dies
All dies are for 3/32 rivets (the small ones)
(In the picture the Avery hole looks bigger but that had to do with camera angle, note the smaller crisper look of the Avery dimple)
I used number drills to test the hole size
A Van's RV14 prepunched hole, right out of the box, will accept a #38 drill (.1015")
A normal Avery die produced a hole #37 (.1040")
A normal Cleveland die hole size the same #37 bit
A Substructure Cleveland die will accept a #34 drill (.1110")
Thus the hole size is 7 thou larger using the Substructure die. It works except that hole now takes a bit more rivet to fill it and any larger hole can be more difficult to rivet. What is more worrisome is that when used thicker material, 40 thou for example, the same as is used for the rear wing spar, I could see some small stress risers around the edge of the dimple hole. This was not evident on the thinner rib material.
Both the Avery and Cleveland normal dies produce a nice final product. The differences are purely up to the individual as to what looks better. The Avery die actually produces a crisper final hole with the outside of the dimple measuring 0.220" vs. and O.D. of Cleveland at 0.230".
As for myself I am not going to continue using the Substructure dies as I see no real visual improvement to the final product and there the two issues of increased hole size and subsequent stress risers on thicker material. The larger hole size was seen when used on thick or thin material.
I would suggest if you really feel the need for a substructure die use the cleveland die and nest an Avery die within it.
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