Sheetmetal dreams.

[C-Bag]

Very cool Bill! Sorry to be dense, but what’s “corking”?

“The dark color on the beveled edges of the block is polyester resin. I soaked the working edges with it and then did a final cleanup sanding. The resin makes the block tougher so it doesn't just crumble when you beat on it.”

This has always mystified me in watching Jere Kirkpatrick and Ron Covel in their use of MDF. The use of resin makes sense. Most times, not being a wood guy, I saved an old Futon frame because it was hardrock maple and that’s what I use if I’m really wanting to beat on some kind frame.

Thanks for sharing.

 

[cwilliamrose]

A little rough yet but no welding required. This one allowed me to refine the steps for the last one. It will get smoothed with some planishing and some light file work.



One more to go.



I use a large C-clamp and a small steel block to apply pressure to the area I'm working on. No need to clamp it all down tight, a little at a time works fine.



First blows are to set the radius of the flange. You want to work towards the edge from the top making sure the aluminum is in good contact with the form block as you move down. I used the wood dowel here since guiding the hammer blows to these small areas is a skill I do not possess.



Just knocked the aluminum around the radius about 20-30°. You do not want to rush this process. Just move the metal a little with each pass.



Second pass. Looks awful doesn't it?



On the third pass I worked the right end down where the form's profile is fairly gentle but I left the rest of it with just a little more angle added.



This is the fourth pass and this is where you need to start being careful and controlling what the wavy edge is doing. What you want here is a series of fairly even waves (called 'tucks' in the metal shaping world) and what you don't want is one or two large tucks that will want to fold over on themselves. I used the white wedge tool held vertically to form these tucks.



Now I'm using that same wedge tool held horizontally to collapse the tucks starting at the very top of the flange.



The tucks are now 'locked in' meaning they can't just flatten back out easily because the top portion is shrunk down snugly to the block.



Another pass with the white wedge. The tucks are shorter yet as the top portion is shrunk down. This is the point where you actually feel like this might work.



After another pass they are shorter yet. A little at a time is the key here.

More coming........

 

[cwilliamrose]

Very cool Bill! Sorry to be dense, but what’s “corking”?

“The dark color on the beveled edges of the block is polyester resin. I soaked the working edges with it and then did a final cleanup sanding. The resin makes the block tougher so it doesn't just crumble when you beat on it.”

This has always mystified me in watching Jere Kirkpatrick and Ron Covel in their use of MDF. The use of resin makes sense. Most times, not being a wood guy, I saved an old Futon frame because it was hardrock maple and that’s what I use if I’m really wanting to beat on some kind frame.

Thanks for sharing.

I think the term 'corking' comes from sealing the boards on a boat by forcing rope or other caulking material into the gaps. The same types of tools can be used to impart shape into metal panels.

And I think the really talented and experienced guys can do things with less brute force than guys like me!

 

[C-Bag]

This comes at a very crucial time in my present project of reforming an aluminum cake pan I’m working on. It’s not as “crucial” because it’s not going on an airplane but getting to finally put the many hours of watching vids to actually working tucks and understanding what they mean by “trapping” them. I also am suffering from less than stellar hammer control so before I go any further I’m going to make my own selection of corking tools. I don’t remember seeing anybody using these before so like I said this comes just at the right time!

 

[cwilliamrose]

The tucks are almost gone but the metal is getting stiffer due to being work hardened. It doesn't move as easily as it did a few minutes ago....



This is about as far as I can go with this corner. I'll need to anneal the flange again to better finish it.



Might as well finish the rest of the flange. Here are the next set of tucks ready for shrinking.




Almost done with the flange.



Could be better but after the second anneal the metal will be more cooperative.



Off the forming block it doesn't look too bad -- from a distance. The soot you see on the panel is from the first annealing I did to the flange.



The flange isn't completely smooth yet. See the detail photos below.














And it doesn't fit too bad here. I'll need to nit-pick the fit, flange angle and overall size and decide where to go from here.

More soon..........

 

[cwilliamrose]

I checked the time stamps and from defining the tucks here;


To finishing them here;


Took 13 minutes and that includes stopping to take five photos. I'd say easily less than 10 minutes for each corner. The entire corner from start to finish was 24 minutes with lots of photo breaks. Most of the time spent on this part is getting ready to do the forming -- making the temples, the blocks, etc.



The first baffle was a bit narrow so there were gaps along each side. I had one more piece of 3003-H14 but rather than use that I decided use the jon boat material I had previously used for the inner covers on the pants. It worked nicely for those parts as I was able to impart some shape without annealing. I made a new blank from that material and, after modifying the form block with some Bondo to widen it out and to add a drain/vent feature I started a new part.




I applied soot to the edge with the OA torch running fairly rich.



This is what it looks like when you're burning off the soot. I just work my way around the edge doing a little at a time.



Until it looks like this. You don't want to overheat the metal so you have to keep the torch moving and be patient with burning off the carbon. Words to live by.....



And the whole thing clamped to the corner of the steel table. Note the clamp block is relieved where the drain feature sits. You need to be able the get in there to work but I made more room than was really necessary.



I figured I'd start with the drain feature since it needs to be stretched and the surrounding area needs to be shrunk. Why shrink it just the have the stretch it later?


Just getting started using mainly the wood dowel and plastic wedge.



I'm trying to move the areas left and right of the drain towards the location so I won't have too much stretching to do. Mostly you just direct your blows in that direction and the metal will try to cooperate.



Got a bit more metal around the drain than I need but that should be OK.



Yep, plenty to work with!



Now I have to shrink that extra metal to get it to lay down.



Not too bad but the relief for the drain being too large allowed the metal to form a little hump which will have to be flattened out.



This turned out to be a scrap/test in part because it was 5052 material and because of the following problem which happened on the second anneal...... More shortly...........

 

[cwilliamrose]

This comes at a very crucial time in my present project of reforming an aluminum cake pan I’m working on. It’s not as “crucial” because it’s not going on an airplane but getting to finally put the many hours of watching vids to actually working tucks and understanding what they mean by “trapping” them. I also am suffering from less than stellar hammer control so before I go any further I’m going to make my own selection of corking tools. I don’t remember seeing anybody using these before so like I said this comes just at the right time!

I'll use any crutch I can think of. No rules in metal shaping! I'm happy to help and I was wondering how that pan mod was going for you.

 

[cwilliamrose]

I applied soot to the inside corner which turned out to be mistake #1.



Everything was going OK but the heat was being trapped in the corners and I got a bit impatient......



And destroyed this corner of the part. Mistake #2 was to get in a hurry.



Stuff happens, and you learn from those episodes.


This is the keeper for the right pant, the third attempt. I got about .650" on the flange width measured on the inside. I'll do a few things differently on the left one and maybe get a good one on the first try.



This is the final form, edges trimmed, flanges smoothed, tooling holes plugged/welded/dressed, etc. The small radius corners are about 1" and I think it would be difficult, for me anyway, to do a smaller radius and get as good a result. BTW, the drain is off center on purpose due to the camber of the main gear which puts these drains at the lowest point.

Thanks for looking!

 

[C-Bag]

I'll use any crutch I can think of. No rules in metal shaping! I'm happy to help and I was wondering how that pan mod was going for you.

The remark Wray Shelin always closes his vids recently really comes home when doing this kind of edge forming. “metal is clay” and when I think back to my school days with modeling clay it’s true. The other thing you mentioned too is a little at a time and patience.

Besides the corking tools I need to make some varied T- dollies. i have a couple of PVC pieces that have really come in handy as dollies. One bullet shaped one especially but it needs to have a base mounted to it so it can be held steady.

My most used vise is a cheap Craftsman wood vise that I put UHMW jaw pads on. Perfect for holding a piece of UHMW that I’m doing the bulk of my reforming on. I could use another wood vise too. I saved this one from a bucket in a junk pile and it has turned into my favorite no mar vise.

 

[cwilliamrose]

I see you have a plastic hammer from HF. I bought three of them so I could customize the heads as needed. They come apart easily which allows you to stick them in the lathe for some precision modification.

I hate to admit it but I don't have any T dollies made. I have been lazy and use an old (Craftsman?) pipe vise my dad had to hold various steel rounds when I need them.

I found this on YouTube about corking tools;

Yeah, metal is clay but it's clay with an attitude.........