I've also got an air powered rivnut tool if you want a shot of it Ali? It's one of these, but I've got a selection of mandrels for it, M4,M5,M6,M8 &10 - I don't think I've got M12....
https://www.rivetwise.co.uk/product...el_pneumatic_hydraulic_rivet_nut_tool_552_440
WOW. :eek: £1300.
It's very kind of you to offer but I would be terrified of harming or loosing it. I have a rivnut tool so I should be OK. ;)
The angle is 3mm so could it be tapped or is it too thin to be strong enough?
 
3mm angle will tap to M5 X 0.8 and hold a reasonably strong thread.
Use a spiral fluted tap and use a battery drill to do the work. https://www.cutwel.co.uk/m5-x-0-8mm...versal-machine-tap-td804-series-yg-1-td804286
You'll be able to tap loads of holes in no time. Make sure you use oil while tapping, for long tap life. ;)
I was thinking maybe better to tap the frame than have the lip of the rivnut sitting out a mm or so. Just to help with sealing the box.
I'll dig out my taps and see what I have.
 
I was thinking maybe better to tap the frame than have the lip of the rivnut sitting out a mm or so. Just to help with sealing the box.
I'll dig out my taps and see what I have.

Or get yourself a set of spiral fluted taps. I bought a set a few years ago, and haven't regretted the small investment one bit.
I'm lazy when it comes to tapping holes, unless it's for something requiring high accuracy. I use my power drill and the spiral taps for anything that just needs a quick thread, or dozen. ;)
 
WOW. :eek: £1300.
It's very kind of you to offer but I would be terrified of harming or loosing it. I have a rivnut tool so I should be OK. ;)
The angle is 3mm so could it be tapped or is it too thin to be strong enough?
I bought mine second hand, gave about a third of that price, but it's a damned good piece of kit, hence offering a loan of it for this priject.

Have any of you guys used those drill taps?
s-l1600.jpg
 
I bought mine second hand, gave about a third of that price, but it's a damned good piece of kit, hence offering a loan of it for this priject.

Have any of you guys used those drill taps?
s-l1600.jpg
I don't have any drill taps but have a few old normal taps I inherited from my dad and some new taps in a box. I'll take a look this weekend.
 
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At the weekend I managed to get another couple of hours at this and have the connections for the battery box sorted.
You can't see it in these photos but I also have the studs welded in for securing the four large modules and nuts for the smaller.

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I bought a bag of M5 high tensile 10.9 bolts and I think the nuts are 8.8. I used spring washers on both sides as I am a little concerned about the copper crushing and loosening over time and I have some lock nuts to put on to prevent the nuts loosening.
To be sure to be sure to be sure. :p
In the last photo you can see how I plan to insulate the connections, the plastic pipe just happens to be for protecting buried electrical cable and has danger high voltage on it :). I'll probably do something to block off the ends but it is very strong as it is. I'll also cut the bolts back and use a couple of layers of heat shrink before fitting the pipe.
 
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I have to admit I'm a bit embarrassed to admit this battery box frame is still not finished after many hours working on it. The space available is very complicated with lots of curves and bits sticking out never mind a rear diff that is mounted on rubber and can move so a simple box will not fit and I have to allow enough clearance for normal diff movement.
This means every time I think I have the shape sorted I realise I need to change something. On Sunday I finally I got it to the point where I was ready for a trial fit once the uprights were welded in. I lowered the rear subframe, secured it in place and found the bottom was a bit too close to the propshaft.

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I cut another 15mm off the height when I saw how close it was but this meant I had to change the way the small modules are secured. Originally I had welded nuts on the inside of the frame but this left the gap at the top of the modules too tight, so I had to cut and grind the nuts out and drill through the angle, tap it and weld nuts on the bottom.
To make matters worse I started with the intention of using M8 bolts or threaded rod but they fitted so tightly in the modules it left zero room for error in my marking and drilling. So after doing the usual mark it, drill it, find the hole has somehow moved, wiggle the drill around to make it fit then give up and use a bigger drill, I was left with big ugly holes and no easy way of welding the nuts to the bottom of the frame without possibly overheating the module. After messing up one side like this I decided to stop, weld up the holes and use the original M6 bolts. This gave much more room for the inevitable drill wander and I also had the sense to drill the holes the correct size to allow them to be tapped.

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You can't see from this photo but after tapping the holes in the Angle I screwed bolts through the holes so they poked out the bottom a little, fitted nuts and then welded the nuts to the bottom to increase the thread depth and make it a little easier to seal the holes.
So now I finally have the modules secure I can finish the top of the frame and think about fitting the sides, after welding in another two uprights on the sides that is. The front of the lid will be higher than the back to allow for sticky out bits in the car.
 
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Making steady progress Ali.
The diff can move about 30mm total (+ or - 15mm) on its mounts, so it's necessary to allow at least that much. It wouldn't be good if the rear propshaft struck the battery box.

It is going together steadily, and that's what matters. Slow and steady wins the race! ;)
 
Making steady progress Ali.
The diff can move about 30mm total (+ or - 15mm) on its mounts, so it's necessary to allow at least that much. It wouldn't be good if the rear propshaft struck the battery box.

It is going together steadily, and that's what matters. Slow and steady wins the race! ;)
Yeah, slow but getting there. ;)
I tried shoving the diff around to see what movement there was and I was able to move it maybe 10mm so I figured while driving maybe 20mm or 25mm each direction. The box should be at least 30mm from the propshaft, hopefully a little more so it should be OK. If there is an issue I suspect new bushes will fix it.
 
Poly the front one for a bit of piece of mind in that respect.
Yes it had occurred to me too that a poly bush would be more secure.
I'm not overly concerned though as it will be very obvious very quickly if there is an issue and the point where they will be closest is a very strong part of the box.
 

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