Early Overriders Project - Epilogue
Having just attached the early overriders to AE22 I thought I should pass on a couple of amendments to the fasteners previously listed and give some suggestions about fitting.
As '22 had lost all the overriders and mounting brackets I have had to start with a clean sheet. The effort has been more than worthwhile. Well done A.C.O.C.
As previously noted by various recipients the early type replica overriders are very nicely made and are spot on in shape and size. For mounting brackets I ordered two rear and two front from Keith Lessiter. They fitted well after a little easing of mounting holes with a round file. As Keith suggests the brackets are self finished so a little bit of fettling, with a file and some emery cloth, before painting, is best.
There is a question of what colour the brackets should be painted and I believe they were mostly painted with the same black paint used on the chassis. However there are examples of brackets painted to match the coachwork. Possibly, like almost everything else at Thames Ditton, it could have been customer choice. As you see above I decided on the matching route for '22. The picture shews the other fasteners required on the rear and reading from left to right we have: The overrider with 5/16" UNF captive nuts fitted, two plain 5/16" washers, two 5/16" UNF hex head screws, two 5/16" BSF Aerotight nuts, two plain 5/16"washers, the rear mounting bracket, one short and one long distance tube, two 5/16" BSF hex head bolts - one 2 3/4" underhead and one 2 1/4" underhead.
The original overrider was fitted with 5/16" UNF captive nuts which made fitting to the brackets really simple and quick. I have tried to find out what nuts were fitted to the square holes in the mounting plates: It seems they were a 'cage nut' which is a square nut enclosed in a loosely fitting square cage which has a spring clip on two sides. This is pushed in to the square hole til the spring clips come through the hole and open out to retain the cage and the nut in place. These are still made and are not expensive. However they are designed to clip into thin sheet metal and will not grip the thicker mounting plates of the overriders. It is simply a matter of finding the clips, designed for thicker metal, which I failed to do: More research required. Fortunately there is an alternative form which has 'wings' on two sides instead of clips and these are easily pop riveted in place.
No great accuracy is required as the nuts are a floppy fit in the cage and allow for a good deal of movement. This is ideal for final alignment of the overrider.
As the picture shews I did spot face the pop rivet holes so that the bracket would mount flush to the overrider plates, but a simple countersink would do as well
The rear fitment is a little more of a fiddle than the front as there are distance tubes involved and the bracket mounting holes are almost in line which means that there is not much space between the heads of the bracket to overrider screws and the nuts for the bracket to chassis bolts. The distance tubes fit with the short one uppermost. Looking at the distance tube arrangement it will appear that the tubes should be chamfered to match the angle of the chassis mounting plate which slopes so that the top is further aft than the bottom. However, having discussed this with David Sanderson, it seems that Thames Ditton left the ends of the distance tubes simply parted off. This means that the distance tubes slope slightly down as they exit through the bodywork. It looks instinctively wrong, but as the bolts are tightened it all comes in to alignment and of course the original holes in the body must have been cut with this in mind.
One useful suggestion I found was to leave all the fasteners loose til everything was in place and aligned. Then tighten the two nuts and bolts and two screws, on each overrider, in step, a little at a time, checking the alignment as you proceed.
As always a picture is worth a great deal more than my droning on:
Note how close the Aerotight BSF nuts are to the UNF screw heads
Once you have mounted the rear overriders you will find the fronts much more straightforward: There are no distance tubes to fit and the bracket to chassis holes do not line up with the bracket to overrider holes, so that getting the Aerotight nuts in place is much easier.
Here is the revised list of the fasteners you will require to do a complete Ace, a little changed from the original list:
8 off 5/16" UNF screws 3/4" underhead Hex head (overrider to bracket)
4 off 5/16" BSF bolts 1 1/4" underhead with 3/4" thread Hex head (bracket to chassis front)
2 off 5/16" BSF bolts 2 3/4" underhead with 1" thread Hex head (bracket to chassis rear)
2 off 5/16" BSF bolts 2 1/4" underhead with 1" thread Hex head (bracket to chassis rear)
8 off 5/16" BSF Aerotight nuts
16 off 5/16" Plain washers
8 off 5/16" UNF cage nuts and cages
Stainless Fastener Sources: Mike Peters at Surplus Supplies
www.polished-stainless.com 01636 636735 surplusmpeters@aol.com
Westfield Fasteners
www.westfieldfasteners.co.uk 01844 201133 enquiries@westfieldfasteners.co.uk.
For the cage nuts go to Revington TR
www.revingtontr.com 01823 698437 info@revingtontr.com
The part numbers for the cage nuts are: Nut RTR5136 and Cage RTR5135.
Being specials for TR 2/3 floor panels these last are unfortunately expensive compared to the other fasteners, but they do make a good job of mounting the overriders.
Barrie Bird