Captive nut / towbar question

[Rob Cowell]

Much excitement today as my tow bracket came lose while retruning from my feed merchant with a couple of tons of feed. Would have been even more exciting yesterday when I had 50 lambs over two mountain passes on the way to market.

I think a captive nut has come lose and allowed the bracket some movement which has lead to the front plate cracking as per piccy below.

The captive nut is attached to the bolt you can see on the left of this pic. It's now completely out. So I just have a hole in the crossmember.

So, captive nut question in the context of something important like a tow bracket. I reckon I can just get a free nut in there by hand / spanner. There are fairly conveniently large holes as part of the cross member pressing that I think will allow this. As long as I can get the torque is this a reasonable solution? I really don't want to cut the crossmember to get a welder in there.

Would seam welding the plate to the crossmember be a bad idea?

Any clever captive nut solutions I haven't seem?

Ta

 

[Shayne]

I guess you snapped it ?

I've snapped one of mine (its not welded to the frame any more) but i can get to it inside the chassis rail by removing the rear bumper so i will , when i get around to it , fish out the old , drill out the hole plus 2 smaller holes either side , drop a bolt down through and tack it with weld in the smaller holes .

It's the best plan i've been able to think up but i'd be happy to hear of any other plan thats less of a ball ache .

 

[Chris]

Generally what I do in these circumstances is take a piece of thick plate; ie a bar about 4mm thick, drill holes in it to exactly match the centres of the originals then weld nuts to that loose plate. Effectively you then have captive nuts, but what stops them turning is the other bolt. I use this method in chassis rails in particular where it's very hard to get a socket or spanner.

 

[Rob Cowell]

Generally what I do in these circumstances is take a piece of thick plate; ie a bar about 4mm thick, drill holes in it to exactly match the centres of the originals then weld nuts to that loose plate. Effectively you then have captive nuts, but what stops them turning is the other bolt. I use this method in chassis rails in particular where it's very hard to get a socket or spanner.

The problem with this approach for me is that the 2nd captive nut is still very much captive. But I could add another nut on the opposite side to achieve the same thing.

Does the captiveness of the nut give me anything other than ease of use?

 

[Chris]

No not really Rob. It's just convenience. I guess it also spreads load like a massive washer would do but that's not it's purpose usually other than where the original wall thickness is very thin, like the chassis rails. YEs getting the other nut off might prove a trial.