bishbosh

Just to correct this point - the volume of the shackle pin in the plate is not what you are interested in and offers absolutely no insight into the strength of the connection. From a pin perspective, you are interested in the two shear planes where the pin exits the face of the plate. The shear area (assuming no threads in the shear planes) is 19^2 PI/4 x 2 = 567mm2. You would then go on to calculate the shear capacity of the pin based on its yield strength, the bearing capacity of the plate, the capacity of the weld group and also potentially the tensile capacity of the weakest section of the plate. this will identify the weakest link. I wont bore you here with those numbers. Another comment is that the configuration of the weld group will also be a factor in the strength of the connection - you cannot just compare sizes (ooo-err missus) and assume all will be well. Also, depending on the direction of the load, the weld will be in a combination of shear and tension / compression, not just tension. Welded recovery points are absolutely fine if, and only if, they are appropriately designed and competently fabricated. (this is not a pop at the OP, just a statement of fact). Lots of love, Bish CEng MICE.

Galvanizing and zinc spray are very different. Galvanizing forms a bond with the parent metal so the interface is a mix of zinc and steel (usually) molecules and so doesn't come off easily. Hot zinc spray is just that - effectively a paint coating so definitely not as durable. In my world, things get zinc sprayed if they are too big / awkward to dip. I would think a cast iron item might struggle with the thermal effects of a galv bath, particularly if it is aged and has some rust pitting. It may come out of the bath in more pieces than it went in! That all said, cast iron is very good at resisting rust and actually just blasting it and re-installing it will probably see you out!

Will the spline extensions need heat treatment / case hardening or some such?

I know I am going to incur the wrath of the ARB fan club here but I wouldn't have another one on any of my vehicles. The only positive comment I can make is they do look good, from the front. But they are very heavy, have very flimsy "recovery" eyes located in a silly position low down and stick out so far at the front they are in a different postcode and ruin approach angles. There, I've said it. Off to hide under a rock now... 😛

You'll need to plug her in to a diagnostics tool to find out. Could be electronic, could be mechanical. It is anyone's guess until you plug her in unfortunately.

Get the existing surface planed to remove the paint and expose the aggregate. Then pour a 10mm aggregate mix to bring up the level. Your concrete supplier should be able to advise on any bonding agent and the mix design. You could even use a repair mortar but that will probably be prohibitively expensive. Avoid any tapering of the thickness below 20mm (2 x nominal aggregate size). You'll have to break out locally if you have high spots. Good luck.

3 packets of smarties and a (dark chocolate, obviously) Bounty.

What's the square access panel on the axle casing? Locker actuator?

What about a unistrut channel instead of drawer runners? Could that be more rigid?

I have one too - she's great - tells me when my dinner is ready and everything!

Paging @Nonimouse

Frankly, I doubt you'll get a bad job from any galvanizers - it isn't a business any tin pot cowboy can set up - takes huge investment and needs a big client base to survive. So I'd just find your nearest one (check out the galvanizer's association's website) and go for it.

The 28 day figure is arbitrary and is usually associated with strength gain and standard tests that are done - i.e. "28 day strength" The screed may have recommended overcoating durations and the paint will certainly say how young the substrate can be. All will be weather sensitive in terms of impact on durations. The best bits of advice from above are 1. Damp meter, 2 the plastic covering and 3 longer is better!

or run the winch rope under the car, to a snatch block at the back of the garage which will give a centralised pull.

That's because welded joints are somewhat less prone to movement than timber joints. If it was a timber gate I'd agree and have the diagonal in compression to minimise any movement as the joint takes up load.

Yep, as Fridge says, cut out the rot (angle grinder or plasma cutter) then weld in repair pieces. Not a job for the feint hearted but definitely doable by a competent DIYer

Suggest also that both diagonals run from top left to bottom right, assuming hinge is on left hand side and that you are welding the joints. Reason being that your highest loaded, and longest member (inner diagonal) is in tension. You could in theory use round bar for the diagonals to save weight but that would make fixing the wood a tad challenging! Angles would be good for the diagonals, sized to suit your preferred fixing method/ the rectangular frame can be box, angle or channel section, again to suit your chosen fixing method. Having said all that though, realistically, strength isn't the issue here, it is fixing the wood and having enough stiffness to not twist a lot when in use, but at 1.8m high you're going to get a fair bit of that unless you go for silly big sections. Box is prettier, angle is lighter and easier to attach stuff to without creating water traps.

My money is on the tyres too. Best fix for large angry rubber is to put about 200g of ceramic airsoft beads into the tyre and remove all lead balancing weights from the wheel rim. Trust me it works!

Connect them in series for the winch. 😈😈

Any benefits to being centred? I suppose you get equal clearance and interchangeable 1/2 shafts but the downside is it doesn't line up with the front diff so will plough its own furrow?

If you use a second hand chassis then get the vehicle tested. You have no idea as to the history of a second hand chassis (not casting aspersions on Simons chassis!) and it could have been damaged before being sold on to you. What have you got to lose other than a bit of time and some cash? Better off knowing the vehicle is roadworthy than it all going tits up and you end up before the beak for manslaughter. We all think we know how to modify our vehicles safely and, consciously or otherwise, take a calculated risk as to their roadworthiness. But none of us have changed suspension components and then gone through a rigorous, documented, handling testing regime that mimics the type approval testing that a manufacturer goes through have we? As I said, a calculated risk. For me, I'd get some written correspondence from your local testing station about the need or otherwise for an IVA for any proposed chassis modifications, including replacement. The written word of the regulations is always going to be up for interpretation (that's why lawyers exist) so at least having something from a reputable source will mean you're starting from the best possible position if things do go wrong. I mean no offence to those who have contributed to this thread but getting advice regarding the law on an internet forum is inappropriate.

Steve Gittins as in Hay on Wye? Lion Garage?https://www.facebook.com/Lion.Garage

You can get door stays that go to 135 degrees (or thereabouts) off ebay for little money. They make the doorway much more usable. (if that makes sense!)

Just to note you can get it back on its wheels without the half shafts

I have a Halfords impact driver. Doesn't get a lot of use - usually the handbrake drum retaining screw or disc to hub screws. https://www.halfords.com/tools/hand-tools/screwdrivers-and-hex-keys/halfords-advanced--impact-driver-and-bits-178172.html Mine came in a cheap plastic case wotsit not the nice metal box shown here but I did buy it over 10 years ago! The tool looks the same though. Has worked faultlessly when called upon.