TR4/4A Fixing dash support

[shoopal]

I would like to fit some kind of captive nut on the dash support bracket to make the installation a bit easier. I was using the chrome bolts that usually hold the dash pad down by the windshield but it is a trick to hold the nut and get a open end back in there. I believe they are 5/16 X 24. Any ideas?

 

[dklawson]

I have no first hand experience with the TR4 or 4A. However, looking online it appears the center brace attaches to the floor/tunnel like many other TRs but the top attaches to the dash rail using either a radio mounting plate or a filler plate when no radio is fitted. Looking at pictures of those parts, you may be able to use PEM nuts of the correct size pressed into the back of the appropriate holes.



You won't find them at the hardware store but you can order them through online stores like McMaster-Carr. Visit McMaster.com and in the search field enter "pem-style nuts". For the larger fasteners you will need to use the type marked as "steel press-fit nuts for sheet metal". Even if you may not be using them in sheet metal they will work fine. Just pay attention to the panel thickness they are made for and order ones slightly shorter than the material thickness of the center brace.

Alternatively, make your own nut bars using steel from the home center. Drill and tap them for the correct threads and JB Weld them to the back of the appropriate part so they will always be where then need to be.

 

[JerryVV]

I use 2 1/2" socket wrenches and no issues on a 4A. The 4 is different as it's a 2 piece support using the radio or a blanking plate but you should be able to still use 2 socket wrenches.

 

[ghawk16]

I'm just bummed I lost my two original chrome bolts as it seems replacements aren't available. But I would just use two sockets (deep if needed)

 

[shoopal]

Send me your mailing address and you will get two of my best ones left in the mail tomorrow. By the way, check out Victoria British 12-5578
I found 2 good ones and the offer still stands

 

[ghawk16]

Send me your mailing address and you will get two of my best ones left in the mail tomorrow. By the way, check out Victoria British 12-5578
I found 2 good ones and the offer still stands

Sorry, had been off the forum a couple of days trying to get my main transportation running again. Sent you a PM. Thanks!!!

 

[shoopal]

attached is picture of bolts

 

[glemon]

I got chrome bolts for my TR250 at the local hardware store, don't know if they are an exact match to the original, but I think it is basically standard sized chromed bolt.

 

[dklawson]

The screws in the link below aren't an exact match for the ones shown above but they are chromed 5/16-24 domed hex heads. They are used on Spitfires to attach the rear bar of the soft top to the body tub.

https://www.spitbits.com/store/21-CHROME-BOLT-WITH-WASHERS-MK41500-2req-P4206.aspx

 

[KVH]

I'm wondering if they'd be best if tack welded. If you use JB Weld and it gives, could it be hard to get the bolt out of the nut?

 

[dklawson]

I'm wondering if they'd be best if tack welded. If you use JB Weld and it gives, could it be hard to get the bolt out of the nut?

If you are referring to my earlier post, no, there is reason it would be more difficult to get the bolt in and out with JB Weld. Where I suggested JB Weld was NOT on a discrete nut but on a "nut bar". As its name suggests, a nut bar is typically a flat piece of of metal tapped in the appropriate places instead of a handful of loose nuts. If you JB Weld (or tack weld... or even tape) the nut bar to the back of the place it is needed, all the necessary tapped holes are in the correct place.

I have used homemade nut bars on many automotive applications where the factory installation called for multiple loose nuts. For example, on my Spitfire I made a simple 2-hole nut bar for the ignition coil. I used 3M double sided trim mounting tape to secure the nut bar to the underside of the dash bulkhead. After that, all I had to do was insert bolts from the top to secure the coil. With the stock arrangement this is a job easiest handled using two people. I'ts a one person job with the nut bar.

Also, if considering tack welding discrete nuts to the back of steel parts, remember to keep a tap handy. Hex nuts tend to distort during tack welding which can make it difficult for the bolt to fit the female threads.

The pictures below are of "factory made" nut bars. I have no idea what they happen to be for... they were just the first pictures I found.

 

[malbaby]

I often use "rivnuts".