The MGA With An Attitude
REASSEMBLING THE BODY SILLS - RT-222
PANEL ALIGNMENT
This is a very advanced subject for Reassembling the Body Sills on the MGA and getting everything to line up in the process.
Question from the class: "What I was wondering about was if you may have some 'real' info on the distance between the front and rear door posts. My MGA is in two sections and I am currently reconnecting them, and...."
Right offhand, the answer is no. Otherwise the rest of this is probably more than you asked for.
Occasionally I see a chassis dimension drawing that was probably intended as a guide for collision repair, but I don't recall ever seeing a body dimension drawing (probably just haven't lived long enough yet). Even if I did have a body dimension drawing I'm not sure I would use it. For restoration work on a single car it should work better to hand align the body parts to get a nice fit. If you were to start by jig fitting the sills and posts with no regard to the other body parts (like they did in production), then you would likely be faced with the same problems aligning the doors and fenders as existed during original production. Even then things didn't line up right, because the various stampings were not of particularly good precision. By hand aligning the body parts you should be able to get a better fit than the factory did (which was actually pretty bad). And I do have a good idea how to go about getting it to fit properly. Here is what I would do. (And if anyone has some better suggestions, by all means speak up.)
First move would be a thorough inspection of the frame to be assured as well as possible that the frame is not bent, so the body will have the best chance of sitting straight in order to achieve good alignment of the sills, doors and fenders. Then place the front and rear sections of the body on the frame, placing cork gaskets in the appropriate locations as will be at final installation. Secure loosely with about 4 bolts in each half, in preparation for minor adjustment. Then fit the doors first. The holy grail of MGA body alignment is good fit for the doors. In essence you will be building the body to fit around the doors (as opposed to jig welding the body first). And allow yourself plenty of time to do this, as the end result of all this effort is directly reflected in the final appearance (and function) when the complete restoration is finished.
The following assumes that the body pillars are already attached to the body. Otherwise you need to attach them very near their final location with screws or small clamps. For now I will assume that the pillars are attached and that the sills are not attached. If you have purchased complete sill and pillar assemblies, then you need to determine a bit later as you go if they fit well enough or if you need to detach the pillars from the sills for better realignment.
Give the hinges a close inspection to determine if any of them are bent. They should be all the same shape with the outer face of the flanges being flat all the way out to the pivot point. I have seen these intentionally deformed to make a door operate when the body is misaligned, so take nothing for granted. The hinge pins should also be snug with little or no play. Worn pins can be replaced. Worn brackets could be bushed, but cheap enough to buy new so don't bother. If in doubt about any of them, buy new hinges.
Attach the hinges and the latch assembly to the door. Hinges should be located as near as possible to the center of the adjustment (not much play here) up/down and left/right. Latch should be positioned firmly against the back panel of the door and centered up/down (not much play here either). Tighten all hinges and latches to the door, and they should not need to be moved again.
Install door(s) on body starting with no shims for the hinges. Tapping plates are inserted through slots from inside the passenger compartment. Locate hinge tapping plates in body approximately in the middle of adjustment range up/down and left/right (lots of room for adjustment here). Tighten the hinges to the body, snug but not permanent yet. Still assuming there are no sills (at least no outer rocker panels) in place at this time.
Attach the striker plate to the body. Tapping plates are inserted through slots from inside the passenger compartment. Use exactly one (stock thickness) shim behind the striker. This is to allow for future realignment of the striker if replacement parts are not all exactly the same dimensions. Note that the shut face panel should be in place when you do this, as this part is effectively a necessary shim for the striker. Use more than one additional shim here only if the door touches the rear body post (which it should not do even with no shims). Start with the striker set loosely near the middle of adjustment range up/down and left/right. Close the door(s) gently while watching the alignment of the latch to the striker. Move front and rear body sections together or apart as necessary for fore/aft alignment of the striker pin in the latch. Move striker up/down as necessary for vertical alignment of the striker pin in the latch. Striker should still be near center of range left/right, and the door should close and latch without binding at this time. Most important, the top corner of the door should not be dragging on the shut face panel. If it does (perish the thought), then you need to add a shim at the bottom hinge to raise the rear of the door.
If you started with complete sill and pillar assemblies, then you should not have to add or delete more than one shim at any one point. If the parts require more shimming than that, then it may be time to seriously consider separating at least one of the pillars from the sill for adjusting to get better alignment.
Install rear fender next, tucking the front edge of the fender behind the flange on the shut face panel. Hang fender loosely with just a couple of bolts to start, and align the front edge of the fender to the back edge of the door first. Move front edge of rear fender fore/aft as necessary to get 1/8" clearance from the back edge of the door all the way top to bottom. Move front of rear fender up/down to position top front corner flush with top of door. Final position of fender here should be close to but not quite sitting on the body at the top. The striker needs to be loosened to move the shut face panel at this time. shut face panel should be positioned with the flange tight against the flange on the rear fender, starting at the top and proceeding down the side. Install screws loosely in flange on shut face panel. Secure font edge of fender here keeping the 1/8" space to the back edge of the door, then tighten the screws in the shutplate flange (and secure the striker again in proper alignment). Attach the bottom flange of the dogleg to the sill (which needs to be there by now, even if only temporarily attached). From there back the rear fender gets aligned to the body as the piping and the rest of the bolts are installed (can be done later), but only after the front edge is aligned and tightly secured.
The front edge of the rear fender will be attached intimately against the door post with no gap and no spacers (except maybe a tiny space at the top). Now you can adjust the door striker left/right to bring the door flush with the rear fender near the top. The bottom corner of the door should then also be flush with the fender by default (yeah, sure). Otherwise you might move the top hinge slightly left/right to align the bottom corner of the door flush with the rear fender. Do not move the bottom hinge for this, as that would misalign the bottom front corner of the door.
You can install the rubber door buffers at this time. Insert the small tapping plate into the rubber buffer, insert this assembly into the slot in the door post, press tightly into place and secure with one screw each in the front face of the shutplate. I have occasionally had to open up the slot in the shutplate slightly to get the buffer to slide in. Also the rubber door buffers I have bought in the past 15 years have all been too thick on the exposed part, and I have needed to grind the rubber down some to get the door to fit flush with the outside of the rear fender. When finished the door should be flush with the rear fender (still 1/8" gap at the back), tight against the buffers, and the latch should hold securely without binding. Note that I am assuming that the sills are not permanently installed yet, so the rear fender will likely need to be removed again for installation of the sills.
If sills and outer rocker panels are already in place, adjust vertical height of hinges to allow 1/8" space between bottom of door skin and sill surface immediately below. If bottom of door is not parallel to sill, then add one shim at a time to one hinge only between the hinge and the body until the door is parallel to the sill with 1/8" vertical clearance. You may end up with one or two shims in one hinge, but the other hinge should still have no shims. Look again at the alignment of the door bottom to the sill on the outside. If necessary, adjust only one hinge at a time. Move bottom hinge left/right to get near flush alignment of the door at bottom front, and move top hinge left right to get near flush alignment of the door at bottom back. Door should still open/close without binding, and latch should still work properly. If you have to do this adjustment, it is likely to end up being somewhat of a compromise between rear flush and bottom flush, in which case you should favor the rear flush alignment and let the bottom flush fit fall where it may (but not so close that the door would touch the rocker panel and cause future paint chipping).
A word of warning here. In past years I have received new outer rocker panels that were too tall on the outer curved surface such that the rocker would hit the bottom edge of the door. If you were installing complete replacement sill assemblies you might accommodate this (tall rocker panel) problem by lowering the sill assemblies to get the proper gap below the door before attaching (welding) the sill to the body. In my case the original sills were still attached in the correct position, and I was replacing only the outer rocker panel. Moving the doors as far as possible to the top of adjustment on the hinges and strikers was not enough to clear the rocker panels.
Also, as these (improper replacement) rocker panels were originally, the dogleg of the rear fender would not reach all the way from the top to bottom flanges. On my first use of these parts I made a crescent cut in the dogleg just below the top flange, raised the top flange to match the odd height of the rocker panel, and then welded in the gap in the dogleg. That car now has non-standard rear fenders to match the non-standard replacement rocker panels. The doors are also raised to the top limit of adjustment, and the bottom of the door still touches the rocker panel and chips the paint there. I will never do that again. If any of the replacement panels are not correct, fix the replacement part. If you modify otherwise good parts of the car to accommodate bad replacement parts, you will soon be known as the DPM (even in your own mind).
This height problem with the outer rocker panel has been around since at least 1977 when I bought mine, and is still with us in the same form in early 2005. It is desirable to "adjust" the rocker panels to proper size, and not to attempt to raise the doors any substantial amount. I thought a reasonable solution might be to straighten and cut and reform the flange at the bottom of the rocker panel to lower the top edge to the proper height, but this is tricky and might remove too much height. The best way to reduce height of the rocker panel is to cut out a narrow strip (about 1/2 inch wide) for the full length just below the top step, and weld it back together at the proper height. Eclectic Motor Works in Holland, Michigan, has recently been supplying properly modified rocker panels for about $100/pr. The rocker panel should be temporarily clamped in place while aligning the door. Try for about 1/8 inch gap along the bottom of the door. When everything lines up to your satisfaction, then you can permanently attach the rocker panel.
During my restoration work I had drilled out the spot welds to remove original rocker panels. The complete body was chemically dipped and electrically etched by RediStrip to bare metal with no rust. I painted all underbody parts with etching primer and two coats of brush applied epoxy paint, including the inside surface of the rocker panel while it was still separate. The rocker panel was then attached with pop rivets to minimize any damage to the paint. Box sections of the sill and pillar assembly were spray injected with rustproofing coating. This seems to be holding up well after 18 years and nearly 200,000 additional miles on all sorts of roads in all sorts of weather.
Getting back to assembly, hang the front fender loosely with a few bolts. Start aligning this part near the front edge of the door. The fender has a mounting flange on the inside just ahead of the door post. This flange generally cannot be modified (and you wouldn't want to), so the distance of the outer surface of the fender from the inner body is fixed (assuming the fender is not malformed). Attach this rear mounting flange with bolts from inside the passenger compartment. Align the top of the fender to match flush with the top of the door, and adjust for a 1/8" gap between the fender and the front edge of the door (raising the front of the fender a bit if necessary to do this). If the door is not flush with the fender on the outside, then you adjust the door hinges left/right (both in unison) to make the door flush with the fender. Attach the bottom flange of the front fender to the sill (which needs to be there by now, even if just temporarily attached). From there forward the front fender gets aligned to the body as the piping and the rest of the bolts are installed (can be done later), but only after the rear edge is aligned and tightly secured.
Now assuming the sill assemblies are still loose, this is the time to align and attach those parts. Temporarily attach the outer rocker panel to the inner sill, then hold the whole assembly in place inside of the fenders and below the door. Pull it up tight against the inside of both fenders with the bottom flanges of the fenders attached to the sill. Attach the sill temporarily to the front and rear body parts while you consider the final alignment of the door. And finally when you get it all aligned to your liking, the last thing is to permanently attach the sill to the main body.
Jumping ahead just a bit, a note on another nasty thing that sometimes happens. After the sills and rocker panels are permanently installed (or if they have never been removed), the front fenders may have a problem attaching at the bottom flange. If the front fender is attached to the body too high the bottom flange will not reach the attachment point at the bottom of the sill. The proper cure for this should be to lower the fender mounting enough to get the bottom flange to bolt up. On the flip side, if the front fender is mounted too low, then when the bottom flange is attached it will leave a substantial space between the fender and the rocker panel, and the fender may protrude a bit outside of being flush with the bottom corner of the door. The proper cure for this should be to raise the fender mounting enough to pull the surface in near the bottom to fit closely to the rocker panel. If you raise or lower the fender to correct the bottom bulge problem, then you might consider realigning the height of the door to match flush at the top of the front fender. This of course creates another compromise with alignment of parts (like the size of the gap below the door), so you then decide which locations are more important and should be favored while fiddling with all of the past adjustments in a repetitive manner.
Sheeesh! This is about the time it can all get somewhat frustrating. The key here is that the combined height of the door and the outer rocker panel (including the bottom door gap) needs to match the total height of the front fender, the same as it needed to match the total height of the rear fender. With the original equipment parts this height issue was the one thing that was generally not a problem (they just left a large gap below the door). Once you get this far you might attach the front fender at the bottom flange and then raise the back of the fender as high as possible to make the bulge at the bottom rear pull up flush against the rocker panel. Ditto with the rear fender, attach at bottom first and then raise the rest to eliminate any excessive bulge at the dogleg. And after having done that to both front and rear fenders, you could raise or lower the door to match flush at the top.
Like I mentioned earlier, at this point of final assembly I was once totally screwed by a too tall outer rocker panel replacement part. Whenever possible, compare replacement parts with the original parts early on to see if you can spot any variations in shape or dimensions. Early cures are usually much easier and cheaper than having to fix things during the final stages of assembly.
For more restoration information you can go here:
www.mgaguru.com/mgtech/restore.htm and check the links near the bottom of page for notes and pictures of restoration work on the Sebring MGA #43 and a Twin Cam called Ratty. These are both MGA Coupes, but virtually identical to the roadster in the body sills.
Now you guys gotta understand that even after all this studying you aren't getting your diploma until you complete the lab session and prove that you can do this stuff. Class dismissed, and happy tinkering.
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