Image and explaination of how a dome/convex shaped is formed

[Ol'fogasaurus]

Since your post of the "Stretcher/Shrinker Kit" didn't come in I was waiting on which style you were talking about.

https://www.bing.com/images/search?q=sh ... &FORM=IGRE

This shows several styles of shrinking and stretching with one of the pix showing an "S-shape" of bent metal using both a shrinker and stretcher tool (they usually come in pairs but you can get them separately too (HF for one sells them).

At the very bottom is a pair of locking pliers that I think the flat part might be serrated some way that can do either shrinking or stretching. I have a couple who's surfaces are flat that I use to do simple stiffening flange type of bends on short pieces of stock. A vice can be used to do the same thing also. I seem to remember other methods of doing the same thing but I can't remember just what they are now. I had to fix my snow shovel this week as it is so old that the AL was starting to fracture. I had a roll of 1/2 flat CRES that I cut a couple of lengths out of then put it in a vice and bent a stiffening flange then screwed it (I couldn't find my pop rivet gun) onto the stiffening flanges of the shovel and so far it is working.

https://superiorsteelfab.com/sheet-meta ... echniques/

This talks about forming metal in different ways. If you look even very simply there is a lot of information on the web; to state the obvious: doing a search then changing the wording around or substituting a different word or words can get you new info than the search you had before. Don't give up on just one search for this same reason.

Remember when we were talking about "dapping" and I posted a kit for small cup shaped things. I have seen presses used to hold a cup shaped form then press down a shaped form that pushes the metal sheet down to form bowl shaped form. The mating parts of the form have to have the proper gap to allow the material to be properly captured but it does work Kind of expensive too but if your metal isn't too thick the pressure needed may not be that great.

Hammering metal, with a special soft tool, into a bag then using an English roller to smooth things out is very commonly used in the custom car industry. An old trick for sure.

Lee

[theKbStockpiler]

Since your post of the "Stretcher/Shrinker Kit" didn't come in I was waiting on which style you were talking about

I'm guessing if the image is too big, STF server makes you click onto the Hotlink to view it.

[Ol'fogasaurus]

PM

[doc]

Great thread!

If you watch tv, the car shows "detail" cutting out rust spot, cardboarding out right size patch, transfer to flat metal, clamp to car, MIG spark. Next shot - perfectly in place, curved, bent, smoothed panel. Wait what happened? Did I miss everything when I went to get that beer? How'd they get it to fit?

Great thread!

[theKbStockpiler]

I'm glad this thread is reaching someone that is interested in it.If this thread only serves to impress on the reader that each metal shape has sort of a blue print to it, that's a good start. I'm planning on letting this thread sit and starting another one where I'm actually working on my next patch piece. In my first patch piece thread First Patch Piece I got the process down that will achieve a decent result.It's obviously not good enough to use ,but the methods have been proven. Only finesse and time have to be added.

[Ol'fogasaurus]

https://www.bing.com/search?q=welding+i ... lang=en-US



Back when I was a kid and body filler came out to replace lead I thought that metal forming was going to be a lost art but the recovery in the last few years had been pretty good. One of the kids I grew up with father was a body many who did things the right way. He sectioned one of the other guys I knew's '56 Buick into a show car. Later it had a glass bubble blown for it but he never picked it up in CA.

Lee

[Ol'fogasaurus]

Doc, sorry about being cute on the panel thing but have you noticed that things have changed on the car channels lately? Spike was bought out by Paramount (I think that is who it was) and their shows are now gone. Motor Trend has now bought out another channel (I forget it's name) and shows there have changed and shows that were on other channels have started to show up there. I occasionally see "car and other vehicle stuff" on other channels but sometimes they are just advertisement shows and not good information shows.

There has been, in the past, a lot of detail on how to fix, rework, weld and rebuild not only panels but mechanical stuff as well. The same with hammer welding and other really cool things; what they forget/are missing is that new people are watching them all the time and that occasional redoing (for education) things would be a good thing to have once in a while. I've noticed a lot of skipping of things in order to have more personality things with people has also been made. I wonder if Chip's antics on Fixer Upper had an affect on this.... Hmmmm!

Lee

[GS guy]

Another comment on the car TV show thing - I've definitely noticed a trend where more detail of how the custom work is performed, less "drama" and "acting/arguing". I stopped watching all the shows for a couple years with all the BS drama, got old real fast. One of my favorites now is Bitch'in Rides - goofy title but does a good job showing guys actually doing the custom metalwork - in detail. More gearhead, less housewives! I'm not a huge fan of the way oversize wheels so in fashion these days, but the tasteful custom metal work execution is fantastic.
As for metal forming - I guess because when I was being trained as an apprentice and learned to use machine tools, I tend to approach a problem with ways to cut/machine something to change it's shape. My pro-welder friend joked about this when I'd bring him parts to weld back up after I did all the "cutting and machining". His approach typically centers on hammers and heat! And it's definitely not hack work!
Jeff

[doc]

I think you guys are reflecting the opinions of many re: the car shows. Paul sr. and jr. pretty much burned everybody out. Internet is the really great source. Chances are some kid in Cali filmed it on his phone and posted it on youtube 4 years ago. But STF (for me) has always been about the learning part. From the vets who have forgotten more than i know to the new guys who are doing things differently, I've enjoyed and learned from them all.

This topic -basic metal forming panel shapes - is killer!