Change of approach for the seats

 Along with a few other jobs (photos of my 'roll bar' to come next!), I've been looking at the seat mounting again. First job was to shrink the holes to M8. Using M14 bolts in the first place was just completely wrong, I'd decided on it based on the holes in the seat rails and not realised the Mazda screws are a 'top hat' design. Basically the head of the bolt is M14, the rest of it is much thinner. Anyway, some M8 penny washers welded in place seems to have done the trick. I won't change the frame, mainly because it's too awkward but also it's good to have a bit of tolerance.

So now it's on to the fixing. My first plan was to use self tappers into the wood. Now that was a really stupid idea!! Any impact at all would have left the seat torn from it's mountings, folded up like a deckchair! I need to fix it to the frame, either by welding directly or by mounting some plates on the frame and securing it to those. Thankfully the positioning of the rails is right up against the sides of the seat, so it wouldn't take much to weld some plate where the fixing holes go. 

It also means that I avoid a problem that I was seeing. The rail mountings have a slightly raised section where the locking mechanism is. Trying to mount that to the seats would have meant either channelling out a section of the wood or raising it up on yet more wood. I don't need to worry about either of those now as the plates will raise the seats slightly anyway.

And then it's on to the fixing. Now that I'm bolting metal to metal it becomes really simple, a captive nut (or bolt?) welded to the plate will provide the relevant anchor, a small recess in the wood will host the head. Actually, thinking about it I'll go for a captive bolt. Or can I... Hmm, I'd best check the clearance before I head out to the DIY store. Yep, it's a bank holiday so I'm going to a DIY store. Shelves to be put up and all that. 

(Later that day...)

Rather than start a brand new post I thought an extension to the existing one would be better. Back to seat belts. The rules are pretty straightforward and common sense, the main one is that the belt cannot be affected by the seat. They class it as a 'change of direction' and basically means that if the belt could apply force to the seat, the seat has to be able to take it.

The upper fixing also needs to be 450mm off the R reference point. That does mean I need to either lift the bracket, or simply work off the roll bar. I think a welded bracket on the cross bar is the easiest option there, it's how they do it in the book.

Time for an obligatory photo;

Yes, this is the passenger seat. I decided very early on that the seat belts would work better 'backwards'. That is the inertia reel and upper mounting would sit inboard rather than outboard, then the buckle sits on the outside.

This shows a few things. First, I need to remember to leave space for the inertia reel. I had forgotten this, but this doesn't cause an issue as I just need to remember to mount the seat on the runners so it can't go that far back. To be fair it doesn't take up that much space anyway, so I'm only losing maybe an inch of rearward travel. I've already figured out that having the seat that far back leaves me completely out of range of the pedals and the wheel!!

Second is the fixings. They need to be proper seat belt fixings that allow the belts to rotate. The standard belts do this by using a sleeve and a series of washers, I'll probably do the same. That'll be for both hip fixings and the shoulder fixings, the inertia reel needs to be fixed. And I mean fixed, these reels only work if they are vertical so they can't be allowed to move. 

Third is the buckle, I need to find out where I put the shorter buckles. I remember ordering them off Ebay, I remember receiving them, I remember having to strip one down to find out why it wasn't working. I just can't find them now!! I might go back through the blog and see where I last had them. 

Fourth is the sleeves. The inertia reel is currently clamped to the chassis rail, however I'll need to put a bolt through to secure it. This will mean drill, weld a sleeve, grind it flat, then bolts in place. Thinking about it only the inertia reel fixings need the sleeves for now, the two lap fixings are there by design and the shoulder fixing can't be done until I sort the roll bar.

So back to the seat fixings to the runners... there's still a few hours of today left so I'll get stuck in.

At least the colour will work nicely with the leatherette seat covers, but they do still need a good clean.

(Edit: It doesn't look like I posted anything about the seat buckles, they arrived September 2021 and the only thing more recent was the batch of ones from the last few weeks. Looks like I might have to find myself some new ones)