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MP&C
09-18-2014, 05:36 AM
Very likely my "sample" windshield will be different from yours, but this is to show the basics of forming a flange mounted windshield opening with minimal tools. Adjust as needed to suit your application. My windshield is in a 52 F7, and though my w/s is still intact, I'm guessing at about a radius of 2.5"


http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture038-2.jpg



I'll use some 5-1/2" square pieces to make the inner and outer corners. This is 18 ga CRS. A center punch is used to keep the compass point from slipping.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture039-2.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture041-2.jpg




Now mark this out with a sharpie, we'll want to be able to see the mark for awhile amongst all the hammer marks




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture042-2.jpg




Now take the measurement of the depth of the windshield mounting flange. If it sets back from the outer edge say, 3/4", I'd make the flanges on each of these corner repairs 1/2" to allow some extra for trimming. Too much extra will make for extra work, so keep it within reason




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture043-1.jpg



Now repeat for the other piece.




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture044-1.jpg




When trimming the excess of an inside corner with tin snips, you'll find multiple cuts will help you to get rid of the bulk so the final cut is pretty accurate. Their capacity rating is for a 1/4" wide cut only, so try to limit each pass to 1/4" wide for best results.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture045-2.jpg




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture046-2.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture047-2.jpg



Here's my 2" dia hammerform I was speaking of before. As technical as this stuff is you can use whatever is handy and works.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture048.jpg



I keep the line up top where I can see what's going on. The first tap with the hammer will show if you are off from your bend line, as you can see. This will show where you are so you can readjust your placement with the next tap.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture049-1.jpg



Looking at the above picture, you can see that the length of our bend line is shorter than the outer perimeter of the flange it is going to form. In essence, once you try to make a 90 degree bend, this excess metal will have a tendency to push the outer corners up.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture050-1.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture051-1.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture052.jpg




....so we'll need some shrinking of the flange edge to bring things flat again. We'll use what's called a "tucking tool", as those shrinker-stretcher machines don't play well with a tight radius. Here I have made a tucking tool out of a large pair of needle nose I never used for anything else. Please note that all sharp edges of the pliers have been rounded off to prevent cutting into the metal.



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture053-1.jpg




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture054.jpg



After using the tool to make some "tucks", or gathering up the excess, the object is to heat up the high spot on one of the tucks, place the two lower edges of the tuck so they are resting against your rounded "anvil", and using a flat hammer, tap the high spot back into itself (flatten it out). Repeat as necessary on all the tucks and add as many tucks as needed until the panel flange is bent to the degree you want, and the panel is flat across.




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture057.jpg




If you're working by yourself, be sure to have a good, secure means to hold your heating device, like a BFG tire.




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture058.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture060.jpg




Much better than before, now for the outer piece. This has a slight radius, so I'll do some more grinding on the welding table to provide one:




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture061.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture062.jpg



http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture064.jpg




As before, the bend line is of different length than the outer flange perimeter. Here the outer dimension is shorter, so it will have a tendency to pull the panel downward as the bend occurs. To get rid of this issue, we will need to stretch the metal towards the edge of the flange, and a slightly crowned hammer will help out.




Place the flange on a flat surface and using the hammer, work the area, especially the outer perimeter where it is shorter, this needs more stretching. <br />





http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture065.jpg




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture067.jpg




It doesn't take long to notice an improvement. Keep working as needed until you have the correct bend you're looking for, and the section is straight across, if that's what you need..





http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture068.jpg




Here I'll normally trim one flange to a nice straight cut, position the other so you have your correct offset, and scribe and trim the other. Weld together, Dress (grind) the welds, and install.





http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture070.jpg




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture071.jpg




http://i5.photobucket.com/albums/y167/rmccartney/New%20shop%20truck%20soon%20to%20have%20ramp%20bed/Picture072.jpg

MP&C
09-18-2014, 05:54 AM
Just to show a sample of where this process could be used elsewhere than the windshield, here's a boot floor for a 51 Triumph Saloon. The center opening is where the petrol tank rests, it's top forming the rest of the floor.



http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/Picture007-1.jpg



Here I've started the replacement, and as you can see the easy straight pieces were formed with a brake, and made separate from the corners



http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/3f0b9fee-1.jpg




http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/651bf37c-1.jpg




Here's the fabrication of the corners, made in two halves, these were hammerformed over the edge of my welding table. Forming the top piece has a tendency to bow the metal as the flange needs a bit of stretching. This is easily accomplished with a slightly crowned body hammer, striking the flange while it was resting against the welding table, and rolling it around to proceed where further stretching is needed. The lower piece was hammerformed over a solid piece of round steel stock, 2" dia, that was clamped upright in a vise.



http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/e57e7b52-1.jpg




All the pieces welded together:




http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/Picture013-2.jpg



Trimming:




http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/Picture014-2.jpg





Welds dressed:




http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/Picture015-2.jpg






Installed:




http://i5.photobucket.com/albums/y167/rmccartney/1951%20Triumph%20Saloon/Picture020-2.jpg

MP&C
09-18-2014, 06:05 AM
Now that we've covered the basics, the same bends in the first post can also be done using an MDF hammerform. Here the MDF is stacked to allow the flange to be folded downward.


http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture630.jpg



The first three layers are aligned and screwed down, then the 18 ga CRS and "locking" layer of MDF is screwed down, through the entire pile using 4" long screws.



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture631.jpg



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture632.jpg



Flange width marked and trimmed. The corners are cleaned of any burrs that may promote cracks to form by using a 3/4" dia drum sander.



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture635.jpg



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture636.jpg



Straight bends are worked with a low crown hammer to start the profile........



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture637.jpg



........and as the corners tighten, this was the most effective stretching device. Repeated overlapping rows made short work of the stretching..



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture641.jpg



....and the door skin hammer was used around the perimeter to "sharpen" the bends...



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture639.jpg



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture640.jpg



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture643.jpg



http://i5.photobucket.com/albums/y167/rmccartney/1955%20Chevy%20Wagon%20Restoration%20Album%202/Picture644.jpg



This same process, through use of various router bits to shape the opening, can be used to add bead details around the opening (stainless trim relief), or a radius rather than a sharp bend, etc. The possibilities are only limited by your imagination.

carls 56 (RIP 11/24/2021)
09-19-2014, 05:17 AM
thanks for sharing Robert. :cool:

chevynut
09-20-2014, 01:04 PM
Cool stuff Robert, as always. I'm going to have to try some hammerforming soon...maybe on my console or valence.