audax wrote:I think some of your problem may lie in your dishing stump. From what I can see, it could be a lot smoother on the interior and maybe a little more concave.
Yeah, it looks like it could be deeper.
Icefire - The cops don't appear to be dished so much as given a wide reverse flare at the top, since the bottom 3/4s of it look bent rather than dished. This seems to be a feature of many of the pieces you've shown us.
Icefire wrote:About planishing, I have already tried that for quite a bit. Probably 30 miniutes.
The photos of the shoulder cops (100_0546.JPG and 100_0549.JPG) look like you missed a lot of spots, maybe 80%? By the time you're finished planishing, there should be no square millimeter of dished surface that hasn't been hit by the planishing hammer. Otherwise, polishing can take forever, unless you use really aggressive sanding and remove way too much of the thickness.
For my second pass of planishing, I will take a small piece of #400 or #600 sandpaper, and rub it lightly over the outside of the steel, all in the same direction. If you hold it at a certain angle to your main light source (positioned off to the left or right side), the fine scratches (which should all be running towards and directly away from you, not left-to-right) will show up as bright highlights because they are reflecting light from the side. Everywhere you hit, the fine scratches mostly disappear, and the spots you hit now reflect whatever is directly across from you (say, a wall). If that wall is dark (or at least not brightly lit), then the hammer mark goes dark too. Essentially, I just keep hitting at all the bright spots until they're gone.
I go by sound, too. If it's more of a "ping" than a "clank", then I move on to another spot, 1/8" away.
The "dollies" you're using for planishing might be fine for certain surfaces, but you should get something like a large mushroom or ball stake, with a more spherical curve. It doesn't have to be a complete sphere, like a shotput, as long as the top is round like part of a sphere. I mostly use one of two cast-iron dumbbells (cheap, from WalMart). A 3-pound one, and (I think) a 10-pound one. Both have had the ends ground and polished to get rid of the rough surface, and one end of each is slightly more tightly curved than the other end, so I have more choice in the radius.
Before I got my big bench vise I found I could use the big dumbbell by sitting it on an upside-down peanut butter jar lid, and duct-taping it down to keep it from wandering around.
That hammer with the pick on the back end looks fine for planishing, especially if you keep it polished.
As for the ball-peen hammer, the ball end might still be too pointy for most dishing. Doming and polishing the flat end might work better for you. Save the ball end for peening rivets, or get a different hammer for all-purpose bashing and peening so you don't wreck the polished domed faces. You can't have too many hammers. -
http://justus.pair.com/ShopPhotos/slides/Hammers4.html