sheet metal gurus chime in

[crewchief888]

ok heres the deal, wife has another one of her "great" ideas.

i need to bend some sheet metal, probably about the same gauge as typical HVAC ductwork.

i need to be able to bend the edges back onto themselves, 180 degrees.

multiple pieces, (14-16) so i need some repeatably, the edge needs to have a finished look to it, my "normal" hammer methods just wont cut it this time

most of the benders i'm looking at dont bend past 90 degrees..

hoping someone with some HVAC ductwork experience can give me an idea on the "correct" way. i'm sure theres a tool out there just for this, and gives me an excuse to add something to the garage

TIA

 

[Superbec]

some finger benders go a bit over 90 ... 120~ maybe ... the rest could be done with some press .

I learned to disregard wife ideas , better than finding solutions for problems that don't exist.

 

[DeltaWye]

Bar folder. The ones I've used have a stop as well so you can set a given depth for repeatability. They're pricey but if you buy one used you can probably sell it for about what you paid for it if you don't need it anymore.

http://aafradio.org/garajmahal/Niagara2.jpg

 

[Dagny]

Fold it as far as you can then turn 180 degrees start on one end of break and fold it shut like 8 to 10 inches at a time with the fingers.

 

[Cue]

Something like this? you would need the press kit too though

http://www.swagoffroad.com/Finger-B...HF-12-Ton-20-Ton-Finger-Brake-Only_p_130.html

 

[crewchief888]

some finger benders go a bit over 90 ... 120~ maybe ... the rest could be done with some press .

I learned to disregard wife ideas , better than finding solutions for problems that don't exist.

she actually has some good ideas, i (typically) have a choice, either make it work, or she'll find some way to BUY what she wants, usually at a much higher price

it keeps my mind occupied.


thanks for the info guys

 

[danski0224]

How long are the sides where the hems need to be made?

Hand seamers are commonly available up to 6" wide, but Midwest has a set that is 15" wide- which would be really difficult to use for anything but residential aluminum soffit/fascia work or really thin sheet metal like 30ga galvanized.

There are hand bar folders that can do most of the job, but you will have to finish the hem by hand somehow.

Using a standard sheet metal apron brake, the piece would be bent over 135* until the stop, then open the brake and smash the hem down. The capacity of the brake would determine how well the smashing part went and how good it looked.

 

[wrenchguy]

how long are these pieces? i got a 36" bendito sheet metal brake that'll bend good some past 90. u can borrow it.

 

[afazz]

I had to hem several edges a few months ago. I bent them to 135 degrees in a brake (as seen in the foreground) then smashed them flat with a few passes through a bead roller (as seen in the background). I don't have a press brake.

 

[Climatecreator]

Bend them in the brake all the way, take it out then put it back in the brake and open and close to squash it down. If using a cleat bender by hand then close it with hand seamers the same way

Sent from my SM-G930V using Tapatalk

 

[matt_i]

Look at Malco and Wiss "folding tools". Those are used to bend flanges in HVAC ductwork. There are two standard depths, as I recall there's a 1" depth and a 3/8" depth. Malco also makes an adjustable version but the inner "fence" doesn't fit quite as tightly as I'd like.

The longer the fold the tougher this will be to do. 12" folds are pretty easy but get into the 24" range and it can be very difficult.

A finger brake (I have a Tennsmith) bends past 90 deg probably to 135 degrees of total included bend (never checked for sure). Then you take the piece out and use the clamping cam of the fingers to smash down the hem in a controlled, neat, manner. This is much easier because of the levers.

A siding brake will bend up to around the same 135 deg but doesn't have the same type of nice flat surface to smash the hem down very well.

 

[Tucko]

Hand brakes will bend to approx. 135 degrees, or if you're using shorter pieces, a Pexto bar folder might be your best bet. A bar folder has a built in back gage for up to 3/4" (I think) hems, and the ability to set a stop to whichever degree you desire. However, I'd suggest a good quality 48" finger brake over a bar folder any day.

 

[crewchief888]

how long are these pieces? i got a 36" bandito sheet metal brake that'll bend good some past 90. u can borrow it.

Thanks for the offer, I've sorta put the project on hold for right now....

Thanks to everybody for the suggestions