Darren schiavello 10 785 views.
Sheet metal pittsburgh seam.
This seam is used as a lengthwise seam at comers of square and rectangular pipes and elbows as well as fittings and ducts.
Push the bend under the top die.
The pittsburgh lock seam fig.
Figure 2 69 shows a cross section of the two pieces of metal to be joined and a cross section of the finished seam.
Lower the bending handle.
Pittsburgh machines make the female pocket of this seam.
The latter is made by bending a 90 degree right angle flange on a brake or by adding right angle flange rolls to the shop s 20ga pittsburgh machine and then rollforming the flange.
Release the brake and remove the sheet metal from the brake.
Pull the top handle closed to squeeze the bend tight and complete the female side of the pittsburgh seam.
Pull the metal forward 1 2 inch to release it from the top die.
It is comprised of two parts.
How to do a sheet metal groove seam using a pittsburgh machine duration.
The pittsburgh seam which is basically a pocket and an extending straight flange and the 90 degree right angle flange.
The former is made by the duct fab shop on a 20 ga standard pitts machine fl p20.