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BJ 7- reinforce sagging frame.

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Roberte

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My car sags and the doors don't fit properly.

I read a post about how to alter the doors but I am also curious whether bolting a piece of flat bar the width of the frame rail to each main frame member is a sensible solution. I ask as I can't afford to have a body shop do the work.

Roberte
 
It's my opinion that if you can get the frame pushed straight somewhat, that reinforcing the frame rails would help. But you should try to ascertain where the frame is bowing. I believe much of the door closure issues are because the frame has bowed aft of the transmission mount in the vicinity between the front leaf spring mounts and the centerline of the rear axle. My car had some frame sag when I did my restoration and I took steps try to correct it. I believe my sag was not from a rusted or weakened frame but was from years of pounding from rallying by the previous owner. Hard shunts from hard driving or terrible roads can cause the underslung frame rails to be drawn up quickly and hit hard on the underside of the rear axle. In any case, if you wish to try to reenforce the frame as you say, bolting pieces will not work. They will only serve to make the frame weaker. And they will eventually work loose. The only way to reenforce/brace/gusset, etc is to weld.
 
Roberte,

In short, no. Since the frame rails are only one part of the overall system of structural parts, just attending to the frame rails will not do much. And as Vette points out, bolting stuff to the frame versus welding will not do much either. The door opening stays constant through the interaction of the frame, the outriggers, and the sills. I would argue that the single most important part of that system is the sill. How do your sills and outriggers look?
 
Thank you for your replies. As I would like to avoid body shop prices I had hoped this solution would be an alternative.

Roberte
 
Roberte said:
My car sags and the doors don't fit properly.

I read a post about how to alter the doors but I am also curious whether bolting a piece of flat bar the width of the frame rail to each main frame member is a sensible solution. I ask as I can't afford to have a body shop do the work.

Roberte
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I believe I still have (most of) this up in my shop's attic; the bars forward of the front hoop are still in the car, since the doors/fenders have to come out to remove them.

I expect this would make a noticeable contribution to a sagging frame...

Healey_Rollcage.jpg
 
Randy Forbes said:
I believe I still have (most of) this up in my shop's attic; the bars forward of the front hoop are still in the car, since the doors/fenders have to come out to remove them.

I expect this would make a noticeable contribution to a sagging frame...
Click to expand...

Probably do a number on the notorious 'scuttle shake,' too.
 
steveg said:
For this solution on this budget, think we're looking for welding some plates to the side of the frame or maybe angle steel.
Click to expand...

This will only work if what you are welding or bolting to is sound .
if the existing frame rails are already sagging the frame is shot and no amount of bracing welding ar adding to to whats there will help .
Would you put a nice new front door in a rotten frame or mount a new tire on buckled old rim .
its time for a full restoration and either extensive repairs to the existing frame or total superstructure replacement.
 
Some years ago I saw U shaped channels that were meant to be welded over the bottom of the frame. ?

Well:
Now if Donald had a good friend in the palace maybe he could have convinced the Queen to give DMH some good metal like Daimler and Jaguar to build his frames out of .:highly_amused:
 
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'fish-plating' frames (if memory serves) was a bit standard in the 40s/50s. If you're trying to keep the beastie on the road, talk to some old folks regards jacking and welding reinforcements to the chassis. Back in the 70s, I saw a rusted out Healey that had angle iron welded to the frame (the angle projected downwards); I don't recall what happened to the car or how it worked out. Seriously: try to figure out if it is frame problems or something otherwise; if frame, where and why. Good fortune to you as a frame replacement is not inexpensive. Doug
 
I've wondered how well some 'tensioning rods' might work. Since most cars sag is in the center of the chassis, it seems--theoretically--you could suspend the car on jackstands placed as near to the center as possible, the pull it in with long rods with turnbuckles, anchored with brackets fitted near the corners.
 
Bob_Spidell said:
I've wondered how well some 'tensioning rods' might work. Since most cars sag is in the center of the chassis, it seems--theoretically--you could suspend the car on jackstands placed as near to the center as possible, the pull it in with long rods with turnbuckles, anchored with brackets fitted near the corners.
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Maybe with a jacked-up 4x4 pickup, but on a Healey you’ld lose half of your ground clearance. Lifting the center and welding angle iron to the bottom edges seems like a slightly better idea.
 
Bob, Your idea has been tried. This is a BN1 w/289 Ford I picked up several years ago. These are not very good pictures but hopefully you can get the gist - obviously the chassis is junk.bridge 1.jpgbridge 2.jpgbridge 3.jpgbridge 4.jpg
Don't know who did this or when but I would guess it was sagging a bit and someone bought a little time with this creative fix.
Dave
 
Add the extra angle iron full length and then a couple of extra stabilzer wheels on a separate axle in the middle as its still going to sag .
the frame is done “a la basil faulty parrott sketch” its expired , passed on , gone to meet its maker etc etc however it is definitely not a stiff as its saggy :highly_amused:
As the saying goes pay me now or pay me later , do it right the first time and restore it properly .
 
The Bentley looks like it is using some lightweight triangulation to add strength, which likely works great. The rods with turnbuckles smack up against the frame on Dave's car don't look like they would do much. It would seem like the moment of inertia would need to be huge to make any change occur--am I saying that right? Am I using the correct concept?
 
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Hi Roberte,

As many have said, it is a reasonably complex situation you want to address. The Healey's structure is based upon a Semi-Monoque understructure which consists of a uni-welded understructure and unstressed body panels bolted on. The main runs of the Healey's structure are formed from relatively light 15 gauge sheet metal formed into box frame runs and, because of little or no factory weather-resistant treatment, often corrodes from the inside to loose strength and continuity.

When considering repairs on the main substructures, it is not uncommon to weld a plate to fix one section of the frame and transfer the flex to cause a tare at another area. Additionally, sagging usually occurs as such supporting components as sills and dog legs and floor panels disintegrate and allow the weak center section of the door opening to allow the jams to close in at the top.

Keep in mind that the Healey's supporting structure (frame) is arched slightly, with the center section higher, to allow settling support when fully loaded. Although this arch is not obvious, it is necessary to reproduce to allow proper separation and spacing of the door jams when. I believe this will be necessary to reproduce when addressing your structural fix.

A while back, when aggressive driving my BJ8 on at a club slalom, I had torn the frame section between right rear support of the front suspension and engine mount. When repairing this section, I cut two 4X4 wood sections to allow for the proper separation and support of the frame sections to be addressed. I would create a number of additional 4x4 wooden supports to provide many more points to maintain and adjust the continuity of the frame when addressing the full extent of the understructure when applying your chosen metal fix to support/reposition the frame (i.e. bottom frame half box sections as Keoke, plates, etc.).

Frame Support.jpg

Ray(64BJ8P1)
 
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We stiffen the rails up with U shaped channel over here. the channels are purpose made with a Vee in the bottom to accommodate the central weld on the rail. They are in roughly 4 foot lengths and are cut and carved around the various bits and pieces welded to the sides of the rails and are welded to the rail along the top edge of the channel and down the sides of any cut outs. from memory they are 3 inches wide and about 2 - 3 inches high.

John Chatham straightened up my BN4 by chaining the front and back down to the floor and jacking up the middle. This was many years ago now and I have no idea how long it lasted.

:cheers:

Bo
 
I have read all the suggestions, unfortunately , none of the suggestions are helpful except replacing the chassis. The patched repairs being suggested, I have seen attempted many times and none of them work. I believe their intentions were good but bad advise. A Metallurgist or structural Engineer could explain how metal stress and metal memory work. The design of the original chassis has caused it to be over stressed because it was under engineered. The car has been constantly changing dimension since being built. The only way to resolve this issue is to redesign the mistake by replacing the chassis with an improved design.
 
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