One Test Shell Made With Revised Procedure for Inlets - Without Sidewall Stretch

Based on my experiments in the last post the first step is to remove the Tall inlet bottom blocks and install the Shorter ones.

The piece of Oak I used to make the shorter blocks wasn't as long as the tall blocks so I used a piece of a Cedar Shim at the far end of the block to hold it in position.  The sheet metal ends before the shim so it never gets hammered forming the shell.

Rather than use an expensive piece of Stainless Steel, I used one of the blanks I had previously made from 1018 Mild Steel.  I didn't make any changes to the shape of the blank, installed it in the form block, clamped it and followed to the shaping processes I used for the older shells.

Once I had the inlets formed with the rounded wooden tool and a good start on the body of the shell I stopped and removed the shell from the form the block.

The inlet bottoms are nicety rounded.  Each one is slightly different due to how the metal slid into the form block cavities.

With the original inlet bottom blocks back in the form block the shell inlet ends now set up off the clamping surface because of the rounded bottoms.  We need to flatten the bottoms a little, moving some steel into the corners, just enough to bolt the clamp board back in place.

For reasons I can't remember I have an older, smaller inlet forming tool, probably covered in an old post. The wide one measures 1-27/32" wide.  The narrow one measures just over 1-5/8", about 1/4" smaller than the wide one.

The wide one is too tight of a fit to use without the steel securely clamped in place.

The small one worked perfect to flatten the bottom nearly to the finished shape without it being clamped.  I think a piece of Oak or Ash with the same bottom shape would also work.

The shell now sets down close enough to the block to allow the clamping board to be re-installed.

The inlet shapes shapes are not yet finished and hold the clamp board up a little.  With a little tightening of nuts that could be installed the board slowly pulled down tight enough to get all nuts on and tight enough to finish shaping the inlets with the wide tool.

Before finishing the rest of the shell I worked all the inlets to their finished shape as I had done on the earlier shells.  I then followed th old procedures to finish shaping  the shell.

A square flat bottom inlet without any thinning or stretch marks in the side walls.  They still measure 0.032" thick, so we have all the strength the shell can give us to support he manifold on a shaking motor.

This should work as well with the expensive Stainless Steel.  Now back to working on the 1/4" thick flanges that get welded to these inlets.

[