Monday, 30 November 2015

Fabrication of a support bracket

I thought this topic deserved a dedicated 'in depth' post as I could not find anything definitive on the interweb about these support brackets.

You may recall that my rear floor pan outriggers were completely shot and so I removed them (see original post here). I was left with these little support brackets/feet that attach to the u-shaped mounts that come off the torsion bar housings:

The problem was that both sides were slightly different lengths, so I assumed that they had been arbitrarily hacked about at some point in the past. This meant that I had no reliable point of reference to work from. I wanted these brackets to be factory correct (if it is a job worth doing, its worth doing right, right?!), so I spent several evenings scouring VW forums for images of other peoples floor pans and amassed a small library of reference photos that revealed glimpses of these elusive brackets. I eventually concluded that there were two distinct types of these support bracket. For all VW Beetle's up to 1967 a short bracket was used and later models had a much longer type.

So, my '65 should have the short type. This was the answer I was hoping for because I was now fairly confident that the bracket on the passengers side of my chassis was correct and unmolested. Unfortunately the other side had not faired so well over the years; it had evidently been trimmed too short and the metal was alarmingly thin in places with pinholes beginning to appear in the corner edges (see pic above). The only course of action was to remove the old crusty bracket and fabricate a replacement using measurements from the good one. Started by grinding off the remains of the old bracket on the drivers side:

Took some initial measurements from the passengers side and devised a plan of action:

Then made a card mock-up of the good bracket:

I transferred the dimensions of the card template to 2mm sheet steel (template was flipped over on to the reverse side of course) then bent, cut and began shaping. Made a series of pie cuts to get the upward curve:

Once I had finessed the gaps to ensure they were forming the correct incline, I filled the spaces using weld. Once again I utilised the copper plate which acted as a backer:

Those welds were then ground off flush. A little welding was required to close up the other curved edge:

Finally the bottom edge was shaped, all welds dressed and given a lick of zinc primer:

It is a difficult shape to show in photos, so I produced a short video clip of the finished article (grab your popcorn!):

The finished bracket looks pretty good and is very close to the original. Shame the only person who will ever see it will be the MOT inspector! Still I think it was beneficial to spend the time making a faithful reproduction as I am still learning and developing my fabrication skills. Might as well perfect these metal working techniques on the unseen areas of the car so that I am semi-pro when I move onto the visible areas of the shell.

The difficulty I am facing now is deciding how best to weld this bracket to the torsion bar housing without negatively affecting the alignment of the new outrigger which fits over the top. I think the best option is to drop the shell back on the chassis to ensure correct alignment of the outriggers, as I can use the bolt holes in the shell for reference. Once am happy that everything fits up nicely, I will weld the support bracket onto the torsion bar housing and then plug weld the outrigger onto the support bracket. This may sound convoluted and vague, but all will become clearer once I start doing it (I hope!)...

Monday, 23 November 2015

Finishing off the bottom plate

Remember when I salvaged the old brake pipe brackets from the rusted old bottom plate (click here)? Well, when I went to weld them onto the new bottom plate I realised that the recessed area stamped into the repro panel was too small widthwise for them to sit in. Typical! As the original panel never had these recesses I decided the best thing to do was to cut them out and weld in new flat metal. The old recess cut out and a card template made up:

New metal (from the left over scraps of the naps hat repro panel!) all welded in:

Ground down the welds and bent the flange to match the profile of the panel. Then finished welding it up, sanded everything smooth and added a lick of primer:

Once I had done the same on the other side I located the factory correct position of the brackets (thankfully I kept the old rusted panel for reference) and plug welded them on:

Continuing on the topside of the frame head, I decided to add a solid weld bead along the small section of flange between the naps hat and the diagonal flanges. I did this in a couple of stitches so that I wouldn't heat up the metal to the point of causing distortion. Here is the first stitch cooling off:

This just left me with the front edge to sort out. After laying down the first lap weld stitch it became evident that the old metal was not holding up well to the intensity of the welder and as a result the edge blew out in a lot of places:

I managed to reconstruct the area using weld material and grinding it back into shape, but it was a long and tedious task. To combat the blow-out I used a copper backing plate on the other sections which really did help to maintain the integrity of the old metalwork. It also proved to be an effective heat sink and drew a lot of the heat away from the area:

I 'pie cut' the curved section (where the profile of the new panel did not closely match the original) and bashed it into submission with the body hammers to get a better fit:

After a lot of fettling I got a passable result:

I then devoted a bit of time tidying the entire frame head, sanded the plug welds flat and filling a few pinholes. This finally concludes the epic frame head saga. Done. Finito. Phew!

Monday, 9 November 2015

Fettle, fettle, fettle!

The time had come for the addition of the frame head bottom plate. I knew the fit was going to be a challenge with this Klokkershite panel and my intuition was correct! The main cause for concern was around the front lip which had not bent up to 90 degrees, so it caused the panel to sit further back than it should. To remedy this I cut a series of slits around the corners of the lip in the report panel to allow for easier manipulation of the steel. I gently bent the lip back so that I could get the whole panel into rough alignment. My thinking was that if I could get 75% of the panel to fit satisfactorily then I could fettle the rest using the persuasion of my body hammers. I spent A LOT of time on this - checking, measuring, making small adjustments and rechecking etc...

I unclamped the bottom plate and began my final preparations before welding it on. Once again I coated the inside of the framehead and naps hat with some FE-123 and once it had dried I mixed up some Mastic 121 and coated the inside for extra rust protection. Also stripped part of the bottom plate with a wire cup and gave it a lick of 121 in the middle and zinc primer around the edges to be welded: 

before permanently sealing everything up, I bent the last section of the new fuel line into place so that it exited through the correct hole in the top of the frame head:

I cleaned up all the framehead flanges and gave them a decent coat of zinc primer:

Drilled out a series of 8mm holes for plug welding, to emulate the factory spot welds:

Starting with the centre of the spine I added the first few tack welds. I then filled the plugs along the Naps Hat flanges before filling in the rest of them on the underside:

To ensure a flush fit in the hard to reach areas I invested in a deep throated G-clamp, which really did the trick here:

Got very positive signs of penetration on the top side. In fact I probably could have eased back a little on the power settings, but at least I know these plugs are super strong:

The bottom plate is almost there now. Just a few tweaks to make along the front edge, a couple of seam welds to add and the brake line brackets to reattach. 

More updates to follow shortly...