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BODY B-PILLAR (Latch Post), Moss Motors - RT-417M1

Photos provided by Todd Pearson

Original B-posts, new B-posts. Shut face panels on original posts and on new posts. These parts are made from 20 gauge sheet steel, about 25% thinner than original construction. This might be serviceable if you can achieve good enough preservation (painting inside) to guarantee they will never go rusty. Since this is a structural door post, the thinner material must affect the rigidity of the car body and the sound and feel off the way the door will close. Personally I would make my own parts from flat stock before I would buy anything made with thin metal, but each to his own.

There is the obvious omission of holes and captive floating nuts (cage nuts) for three screws to secure the shut face panels along the outboard flange. It is left up to the installer to drill holes and install these cage nuts (if you can find a source). A rather crude way out is to dimple the post with a bull nose punch and heavy hammer, then drill a smaller hole for a sheet metal screw.

Next flaw is breaks in the forward flange apparently cut to facilitate forming of the shallow pocket for the striker plate. These cuts may be required for low volume hand forming of the parts (from this supplier), but the cuts should be welded up and ground smooth after fabrication. In this case the extra work is again left up to the installer.

The two gusset plates on the rear face should be extended rearward at 30 to 45 degree angle from horizontal. These are "folded" down almost against the rear plate. It could be shipping damage, but might have been done intentionally to facilitate packaging for shipping. Either way the gussets will need to be reformed to the proper position at installation.


This assembly is missing a vertical flange at the top end of the outer cover (although it may not have been original issue). The flanges at the breaks in the vicinity of the striker plate depression appear to be formed in the proper plane. The outer cover plate seems to be securely welded, but has some burn through or blow holes the should be welded shut. The outboard closure panel appears to be crowned where it should be flat across. Not sure from these photos if it has the right taper angle on top.

Another obvious flaw is lack of welding for the inside brace on the striker plate mount. This one is not even touching the rear panel where it should be welded for mechanical support. This is a stress point in the body structure from impact of the latch when you slam the door. It will also likely have something to do with resisting motion that could lead to popping the door latch when you hit a bump in the road.

Moss Motor's response to inquiry about the quality was, "If not satisfied send them back".

Addendum January 19, 2017:
Now nother problem with the Moss B-pillars. Paul G in Talking Rock, Georgia, USA reports:
"When clamping to the EXACT 1/64" position of what was left of the original B, there are severe gaps to the rear of the B where it needs to be welded back to the body. Even pushing hard on the back side doesn't come close to contacting the body. The inboard forward part of the original B was still secured to the body".

There is supposed to be a 4-degree angle on the front face of the B-pillar. Perhaps there is. However, that should leave the flange(that you have clamped) at 86-degrees bend angle. If that flange was bent 90-degrees to the front face, it would push the entire assembly out by 4-degrees, leaving a gap at the back similar to what you show in the pictures.

On Jan 24, 2017, Paul G reports:
"Spot on! The new unit has approximately a 4 degree angle OK except the wrong way. That means the bend angle is off by at least 8°! Plans are to make a 4° wood template on the band saw and reform to the proper angle".

Moss Motors - More information

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