Nothing has dropped off the old gal for a while now, and sods law just as i was thinking about it the rear bumper/towbar collapsed on me last Wednesday
So i was reversing up the track with a trailer load of type 1 and something went 'twang, crunch'...
Thought i'd just hit a big stone and snapped a mud guard off the trailer! So i hops out and checks, nope not that, looks round the truck, Hmm, something looks a bit strange with the towbar! The braces had rusted through and reversing had folded the hitch forward under the back end, splitting the wafer thin tube in several places and generally B******ing it beyond use!
Then i realised i needed the trailer first thing on Sat morning to go up to the auctions to pick up a small tractor! So a mad scramble ensued to get a working towbar made in time!
For those that i spoke to a few months back, making a new towbar was on my list of things to do as it was looking a little dicey when i bought the truck, but as usual it went on the back burner as parts have been dropping off the farm machinery which needed welding back up or rebuilding!
Incidentally, before someone says ''jeeze!! did you make that strong enough?''
Due to the rush to get it fixed, most of the steel
... ok, All the steel was leftovers from fixing considerably bigger machinery than a 4x4
So without further ado, onto the pics and how to:
Hard to see just how stoved in it was, but the only thing holding it together at this point was the step plate on the top which was surprisingly rust free!
New bumper cutting list:
x2 - washing up liquid bottles
x1 - kitchen towel tube
x1 roll of double sided tape
various poster paints
No wait, that was last nights Blue Peter...
x2 - 1700mm lengths of 70 x 70 x 5mm box (34.35Kg)
x2 - 500mm lengths of 150 x 12mm flat bar (14.13Kg)
x1 - 350mm Length of 150 x 12mm flat bar (0.4Kg)
x2 - 1000mm lengths of 30 x 30 x 3mm box (5.1Kg)
x1 - half Litre of fresh engine oil (i think i used hydraulic oil as it was to hand!)
Approx 6Kg of various welding rods and scraps of sheet steel for capping off the box with.
Salvaged mounting plates from the original bumper (5kg ish).
Total ~64Kg (no wonder it too 3 of us to get it back on the truck lmao)
1. Weld the two 1700mm lengths of box section together like so.
2. Cut chamfers into each end of what will be the bottom of the bumper, i cut mine about 120mm in and 65mm high.
3. Using 6mm sheet steel scraps cap off just one end of the bumper for now, taking care not to have any pin-holes in your welds!
4. Up end the bar with the capped end down and pour in 250ml of oil into each length of box. This will coat the inside of the box and stop any residual moisture from rotting the box from the inside
i have been doing this for some years now and have found it to be very effective!
5. Using more scraps of sheet, weld up the other end of the boxes.
A good tip here is have a helper heat the length of the box with a blowtorch as you make your final weld, this makes the air in the box expand and stops the weld from blowing out as you're trying to seal the end. When the box cools it will also create a slight vacuum which also helps with corrosion resistance.
6. One finished bumper after a quick lick of red oxide.
7. Put the bumper on one side for now and move onto the mounts.
8. Cut back the original mounting plates and weld on the 500mm lengths of 150mm bar.
9. Using 2 bolts, bolt the modified mounts back onto the chasis.
10. Get a friend to help you stand the bumper onto the modified mounts, eye everything up check your spacings and mark up the bumper mounts to notch them out.
11. Put the bumper back on, make adjustments until happy, then mark up the bumper where the mounts will be welded.
12. Weld the bumper to the mounts, I took the mounts off the truck and welded it up on the bench for speed, however with doing it that way as i welded one of the mounts it shifted by a couple of mm hence why it will look a little out on later pics!
If you weld up with it in place on the truck DO NOT weld with the battery connected
, its also good practice to disconnect the starter/alternator as well!
13. Take the 350 x 150mm plate and centre on your bumper, weld up, cut and weld in the braces.I would suggest using angle iron for the braces rather than box (but i didn't have any!), because cutting double angles by hand is very awkward and time consuming
14. Since it took the best part of a day to get the old bumper un-bolted, by this point it was 11pm on Fri so i bolted it all up and slapped the tow hitch on ready for the following morning!
2mm = looking well out! had it have not been such a hurry i'd have either spotted the movement before welding or, would have noticed sooner and could have corrected! this has cost me a couple of hours extra work this weekend!
Always double, and triple check measurements especially when welding something you cant clamp!
I had a day off today so i figured i'd get the bumper back off to get it finished off properly, and to get it lined up re-aligned after one of the mounts moved during welding on Fri night!
15. recovery points... Not needed but always handy to have especially on a farm! they are made of 2 pieces of 16mm plate, one piece was welded on first then another piece butted up and then welded up so there is effectively a weld point in the centre of the point as well as round the edge.
Well i could have bought in tested and toughened weld on recovery points, but at some point its likely that they may be overloaded for a short time and having them twist and bend is preferable to have one shatter whilst there is a tensioned cable attached!
16. Shackles, 2x 50mm hoop shackles, tested to 3.5T. The bumper will be pained up with some good old Hammerite Satin Black. Figured you can't go wrong with yellow n black
The paint is a rubberised industrial coating for offshore use (scrounged some from a fabricators down on the docks)
17. The tow hitch is off and a 350mm adjustable drop plate (landy style) will be fitted when it arrives! I quite often have agri equipment on tow around the fields and could really do with the ring hitch high up at times!