23 May 2023
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Welding is a difficult skill to master, but we can learn from the pros
: credit: © Jake Shoolheifer
Don’t be daunted by cracked, corroded and dented aluminium bodywork. Jake Shoolheifer explains pro repair techniques we can all learn
Need to know
Time: 3 hours (basic repair to a single panel)
Cost: From £30
Difficulty: 2 out of 5 (4 out of 5 if welding)
Models: 1948-2016 Series, 90/110, Defender (old style), aluminium bodied.
Tools needed: Metal shears or tin snips, hammer and dolly, drill and drill bits, one-component sealant adhesive for use with metals, sand paper or Scotch-Brite, angle grinder (not essential), permanent marker, heat gun or blow torch.
Work safely:
• Always wear eye protection when using grinding equipment, using a hammer and dolly and when there is any chance of flying debris
• Gloves should be worn when handling sheet metal and when using tin snips, shears or a grinder
• Keep your fingers and loose clothing out of the way of the shears
• Ear protection must be worn when panel beating and peening rivets and using a grinder
• Wearing a respiratory mask is advisable when welding aluminium and when sanding and prepping the surface
• Wear fire-retardant gloves when annealing the aluminium and leave to cool in a safe place
Suggested material sources:
Marker pen: sharpie.com
Rivets: spaldingfasteners.co.uk
CT1 adhesive: Builders’ merchants
Sealant: Sikaflex 221 (or similar)
Years of hard work, accident damage and the dreaded electrolytic corrosion can take its toll on the bodywork of your Land Rover. Whether it be a 1948 Series I or a last off the line 2016 Defender, seven or 75-years old, the globally-renowned silhouette of their aluminium body will have received some abuse in its lifetime.
There are plenty of people out there now remanufacturing Land Rover bodywork, but replacement panels may not be the answer for you or your vehicle if the aim is to maintain originality, cost or sentimentality. Repairing bodywork using the techniques described here will not achieve better-than-factory results so, if that’s what you’re after, then replacement will be your best option.
Some of you may have seen our restorations from Julian Shoolheifer Ltd and will know that we strive to maintain as many original components as possible, preferring true restoration or conservation over replacement. We never just bolt the bodywork back on, instead, we repair, strengthen and improve all panels whether the final outcome is patina or fully painted. This feature will show the methods we sometimes use in order to achieve this, and how you will also be able to achieve this yourself.
Over the years, Land Rover wings changed in thickness and alloy composition, but these methods are still relevant to all aluminium-bodied vehicles. We use a variety of techniques for repair and they all have their own pros and cons but, with all panels, you’ll be fighting the same battles: stretching, corrosion, distortion and fragility, and you have to assess these before you begin the repairs.
I’ll be using the body panels off one of our current restoration projects, a 1948 SI, to demonstrate typical repairs and how we go about them. This vehicle came to us looking as what can only be described as a mint-coloured boiled sweet when viewed from ten feet away but, up close, the work was atrocious and done to deceive.
We are undertaking a full restoration of the vehicle and, as part of it, the bodywork needed repairing. Each panel weighed several times that of standard panels and, unsurprisingly, the wing panels had nearly 20mm of filler slathered over them in places. Not good. These panels have all been fully dismantled and sodablasted, which is one of the best ways to remove paint gently from Land Rover body panels. Sandblasting is way too aggressive and will cause stretching and damage, so should be avoided. Here are some of the panel restoration techniques we employ.
Riveting
Spot-weld fix: Countersunk rivets are an extremely good way of adding in strengtheners or re-joining panels where the old spot-welds have broken away.
Worked in: Here, a hole the size of the rivet shank is drilled, countersunk top and bottom, and the rivet peened over. The rivet head can be sanded flush with the panel, creating a seamless repair.
Subtle repair: Countersunk rivets can also be installed with care into painted bodywork and then carefully touched in, to repair broken spot-welds without disturbing the panel in any way.
Adhesive repairs
Modern method: Glued repairs are another brilliant and sympathetic form of body repair on aluminium. You don’t need any specialist equipment either, and the adhesives are extremely strong and durable.
Multi-use: Glued repairs can re-enforce thin or fragile material, as here where the backs of the wings are typically thin and corroded. Ensure the inner face is extremely clean.
Maker’s instructions: Check the glue is compatible with bonding metals, and the cure time. Follow this strictly and keep the repair section tightly clamped to the panel until set.
Distortion-free: A patch can also be glued in as a surface repair with a backing piece to replace damaged or missing metal, where welding would create too much distortion.
Reinforcement: If welding would create too much distortion, a glued strengthener can be used behind the cracking to help return structural integrity to the compromised area of the panel.
Panel straightening
Annealing: To remove dents and distortion you will first need to anneal the aluminium (to reduce the hardness and stresses to make it more workable). There are various methods for this, but I personally apply some squiggles using a Sharpie permanent marker on the desired area, then apply heat until the marks begin to go transparent (this shows the metal is around 300 degrees Celsius) and then allow to cool.
Changing properties: You will ideally need a basic panel beating kit to remove dents and damage. Try to be as conservative as possible because denting will stretch the metal and there is only so much dent removal you can do without the panel bulging out and stretching even more. Shrinking the panel will then be the only option, and that’s a skilled job. Be aware that the aluminium will start to become tougher to manipulate after a while of removing the damage, and so re-annealing may be required.
Profiling: To remove damage in areas with a complex shape, such as the curved edge of a wing panel, it sometimes helps to create a former. I traced the shape of the wing in a non-distorted area onto some plywood. This can be gently hammered into a dented area on the wing, supported by a sandbag, to return the proper profile.
Stop the crack: Occasionally, in high-stress areas, cracks can appear in the metal. Drilling each end of the crack with a small drill bit can help prevent this spreading. A glued backing piece will help take the stress off the area.
Welding and higher difficulty repairs
Welding care: Welded repairs are one of the strongest ways to patch aluminium bodywork. But not only will you require expensive machinery (an AC-capable TIG welder, ideally) but the heat from welding can create more damage than you started with, especially if the panel is stretched or creased.
Prep is key: If you decide to make a welded repair, preparation is key. Make sure the panel is completely clean of any contaminants, front and back along with the patch piece. Old Birmabright is notoriously difficult to weld but, with patience, preparation and practice. it does join. But don’t expect it to be Instagram pretty.
Correct materials: Match your patching material as closely to the body material as possible. Birmabright 2 (used on Series I and II) is closest to modern 5251 series alloy. Appropriate compatible filler rod must be used; in this case 1.6mm 5356 welding rod.
Finishing process: With the benefit of lots of careful finishing work, sidelight holes previously drilled can be almost seamlessly repaired, along with old bolt holes and new repair sections.
Welding and paint: Repair sections can be welded into painted bodywork too, but extra time must be taken to reduce heat, and regular cooling of the panel must be undertaken. You will then be able to colour-match paint to the original to touch-in the repair – a near seamless result is possible.
Material stability: Due to the self-hardening properties of Birmabright (the alloy brand used on older Land Rovers), cracks can appear in high stress areas such as around spot-welds and bolt holes. If the metal is stable enough, you can drill the ends, clean out the crack and then weld it.
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