I just picked up a set a of CP lower dies made by Hoosier on e-bay and plan on building a hand held planishing hammer. My thought is a tube frame, air hammer and a flat rivet head for a top die. I have some questions for those who have built these before: 1. I want to make the frame light, but if it is too light it won't be good- any recomendations on frame material- I was thinking 3/4 heavy wall tube?? 2. Air hammers- what BPM should I look for? 3. Upper die- is a rivet head good enough or should I spring for the hoosier upper die? (I think it is around $80). 4. Throat size- how deep should I make it? I plan on using this to work on my 34 coupe with extensive roll over roof damage. 5. Lower die holder- what material should I make it out of so my dies don't get stuck in it? If you have not seen the hoosier dies, check them out, they look nice!
heres one, might give you some ideas, http://allshops.org/cgi-bin/community/communityalbums.cgi?action=openalbum&albumid=9980294362382
The antique one I got to play with had a frame of about 2 1/4' tubing, it actually had three with different throat depths. You just swapped them out when needed. I think the one that was in the machine the most had an 18" depth.
Hi Duke, I made mine from 1/2" square tubing bent to fit. A 4X rivet gun and steel tubing for the die holder and riveter sleeve. It is flexible which is handy for lumpy work. You squeeze it together to stretch or smooth where you need more pressure. An inline regulator is a must. You might want to make several frames. The longest one should use heavier material and the shorter one like mine would be light weight. Picture attached. You can see it in action in my youtube videos below: CMB #2 if I remember right. John www.ghiaspecialties.com
I always thought it would be really cool to have one of these! Good idea! Always thought a handheld english wheel would be helpful as well!
Thanks for the info so far guys. I like the idea of several frames. What is the main difference between using a 4X rivet gun and a quality long barrel air hammer? I can buy an air hammer local, but I will need to find a rivet gun online. Thanks
Hi Duke, The riveter has a teasable trigger making it a slightly more variable at the trigger. Jim Bailie said something to the effect of not needing a riveter, that an air hammer works just fine. If you search his albums on metalshapers.org you will probably find something about it. I do like the teasable trigger on my riveter, but most of the variation in hit strength, and rapidity is done with the regulator. John www.ghiaspecialties.com
the larger riveters also use a larger shaft , the small zip guns use a .401 shaft , so if you already have dies make sure you match them Beaulieu
FWIW, I just picked up a used 4x CP rivet gun, and I've had some success shaping sheet metal by just using the rivet gun in my hand and a dolly for the anvil. I even rounded off the head of an 8# sledge hammer, clamped it in my bench vise, and used that like a post dolly. For the rivet set (The "bit" you put in the rivet gun), I'm using a flush set, which has a round (about 7/8" dia.) flat surface not unlike the business end of a good body hammer. (Very much like the one in John's photos above.) I like the rivet gun's teasable trigger. I'm just learning how to use the thing, so it's nice to be able to go a little slower. One other nice thing I've discovered is that you can hammer off-dolly using this method. I still have thoughts of making a frame, though.
Another place that you might check is www.metalmeet.com One of the MetalMeet guys made a scissor like handheld hammer about six years ago, out of aluminum and it seemed to work well.
Figure out a way to control air with a foot-pedal for bpm speed, and yer golden! http://www.autobody101.com/articles/article.php?title=Home Made Planishing Hammer here's another.
Yardstore.com should have flat Upper Dies. Much more reasonable $$$ than Hoosier. I would go with larger cross section, thin wall tubing, to get stiffness without un-necessary weight.
I will agree with Ian. As for the upper die, do a search for rivet sets, I bought one off of Ebay for $20 a few years ago.