MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Screws for Bottom Main Rail

I'm sure that this has been discussed a thousand times ...

What is the preferred material and style for screws that hold the bottom main rails to the body frames? New ash main rails from Abingdon Spares. Rails pre-drilled for screws. Screws lubed with bees wax. Screw heads will be painted.
+ Plain steel
+ Zinc plated steel
+ Brass
+ Stainless 18-8
+ Stainless 316

Steel and zinc plated steel: Rusts and corrodes over time. Strongest type of screw.

Brass: Does not corrode. Head can be damaged or twisted. A previous owner of my TF attached the main rails with brass screws. Remained tight.

Stainless Steel: Does not corrode: The heads of most stainless steel screws that I have used are easily twisted off. Most manufacturers state so.

After attaching the rails, I will remove them to blast and paint the frame rails, and to apply preservative to the main rails. So the screw hole will be used twice.

Thanks for your help,

Lonnie
TF7211
LM Cook

Lonnie. I use SS SMS predrilled to the appropriate size. Bees wax to lubricate and seal. Out of convenience I’ve order my screws from FTFU in the size and numbers I need. I also add 10-20% to the order totals as spares. I’ve only broke screws when using the box store junk. I have bodged the screw slots when I haven’t predrilled to the correct size and size depth. I’ll also set the clutch on my dewalt driver on a looser setting and not use screw mode. Running the screw in and out a few times when it stalls will generally get it driven all the way in place if needed. Also be sure to buy spare bits and if the screw head gets bodged change it out with a new screw. Nothing like fighting bad screws later on should you need to fix something.

Also if you doing mock ups and will be trial fitting timbers, go down a screw size so that when your ready to do your final assembly you’ll have solid meat for the finish screw to bite into. Otherwise you
May be pulling wood out of the hole with repeated operations and then have to fixe the hole or go oversized with a screw

Bill Chasser
TD-4834
W A Chasser

Thanks Bill -

Probably a stupid newbee question ... what are Stainless Steel “SMS” screws?

Lonnie
TF7211
LM Cook

Lonnie,

I use steel or zinc plated slot head screws.

I know you are probably aware of this, but of course the main wood 'rails'
were connected to the frame with both screws and bolts originally.
I have seen quite a few rebuilt cars over time with screws only used !

Cheers
Rob Grantham
Rob Grantham

Rob -

Thanks. I did not know about bolts in the main rails. Where are they used? I can use any tips and info that you can give to me.

The main beams on my TF were made by a previous owner in the 60s. Only wood screws were used to hold them to the frame rails. I am replacing the beams with new from AS

Bill C -
I found the screws on FTFU. “SMS” = “Sheet Metal Screws”. I thought that all sheet metal screws are are pan head. FTFU has flat head slotted sheet metal screws. Thanks for the info.

Lonnie
TF7211

LM Cook

Long bolts are used to hold the running boards to the main rails.
Dave H
Dave Hill

Sorry Lonnie, I didn’t see your follow up post but you figured it out.
W A Chasser

Lonnie,

Bearing in mind that Abingdon did not necessarily drill their holes in
our coach built cars with extreme accuracy , you may find that only one(1)
of the bolts holding the running boards is actually going through to gather up the front quarter panel, running board bracket, main rail wood and steel sub frame !

The main wood rail needs to be seriously bolted (also screwed) through the steel subframe. Three(3) bolts (1/4" BSF ) are used. The heads of these bolts are countersunk into the main rail wood in order to clear the front lquarter panel 's inner surface i.e. these bolts are in place BEFORE the front quarter panel is affixed to the car. Perhaps this is why these bolts are often missing on rebuilds !

If you have a careful look at the steel sub frame, holes will be evident through which these bolts can be applied.


Cheers
Rob Grantham
TF3719("Aramis"),TF9177(Athos).
Rob Grantham

Rob -

Thanks. That's exactly what I need to know. Bolts plus screws makes sense. There were no hex bolts through the body rails of my TF.

See photo of the passenger body frame on my LHD TF.

1 & 8 = straight non-chamfered 1/4" hole directly behind the tenon of the latch pillar and hinge pillar. A counter sunk hole for a hex head bolt and washer will remove at least half of the thickness of the tenons.

5 = the third of three non-chamfered 1/4" holes for hex bolt.

3 = big ragged hole for bolt that secures front fender and running board to bottom main rail and body frame.

2, 4, 6, 7 = chamfered 1/4" holes for flat head wood screws into bottom main rail.

As you noted, the middle and rear bolts for the running boards go through the bottom main rail but not through the body frame.

See my next post … bolts and screws on TF9052.

Lonnie
TF7211






LM Cook

This is a photo of TF9052 from Chris Couper's website. Driver's side (LHD)

> What can you tell me about the nut and spacer for the bolt that joins the front fender and running board to the bottom main rail and body frame? Looks like a philidas self locking nut and some type of spacer plus washer.

> Flat head wood screws can be seen in chamfered holes #2 & #4 in the photo in my previous post.

> A nut and bolt can be seen in non-chamfered hole #5 in the photo in my previous post.

Thanks again for the information. Two members of our MG club are coming to my house tomorrow morning to help me with the wood. Your info on screws and bolts will put us on the right path.

Lonnie
TF7211


LM Cook

Should a flat head or pan head bolt be used in holes # 1&8 for the tenons of the latch and hinge pillars instead of a hex head and washer? This would not remove as much wood from the tenon as a hex and washer.

Thanks,

Lonnie
TF7211
LM Cook

Lonnie,

I think originally the 'tenons' were wood screwed together i.e. no bolting in that area.

Cheers
Rob Grantham
Rob Grantham

This thread was discussed between 30/11/2018 and 09/12/2018

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now