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MG TD TF 1500 - Seat back springs

I need to do a major repair to my TD seat back wire frame.
I have looked at Dave's great pictures and scanned the archives where I have found there are a total of 21 springs, however would anyone be able to tell me the diameter of the spring. The springs being conical have a different diameter at each end. I can purchase springs of 4", 6" and 8" size but which ones? I think possibly the 4" diameter one is correct and also what would be the free length.
Am I correct in assuming each of the 21 springs are the same.
Many thanks or your help.
John
John Walton

There are at least 3 different lengths to the seat back springs.
This was done to provide side to side restraint.
The edges and center have more coils and are longer.
Unfortunately I did not document these dimensions when I had mine apart.

Jim B.
JA Benjamin

When I say length, they different coil/turn counts also.

Jim B.
JA Benjamin

Thanks Jim

I think this would mean the spring rates would be different.
I think I can get the springs but which ones? and I guess the longer ones go on the outside and in the centre with the smaller at the back of where one sits. Have to think about this one.

John
John Walton

I agree that there are at least three different lengths from about 3 1/4" to 4 3/4". There are 21 springs as you say. The diameter of the big end appears to average about 3 1/2" and the small end about 2 1/2".

Here's a pic of my beyond hope spring back. I purchased one from Hugh Pite that was rough (he warned me!) but not nearly as bad as mine. I was able to salvage it with some effort. I'm in the process of re-covering it.

Does anyone have good photos of the detail of how the material is applied to the back of the seat back?

Kirk Trigg

>
>Does anyone have good photos of the detail of how the >material is applied to the back of the seat back?
>

Horst has some excellent details in his book.

Here is what I found on my old seat back.
Next to the springs is a layer of burlap.
This is not included in the Moss kit. I got mine at craft store.
Then a layer of horse hair.
Again not included in the moss kit. It is available at additional cost.
I bought it just because it was available. Something else might be better.
Then there appears to be a layer if felt like material.
Mine was black and I believe my upholstery was beige.

Jim B.
JA Benjamin

Thank you Jim B and Kirk for your information it was most helpful.
I have contacted an upholstery supplier and the springs he has are too stiff and for our application we need a softer spring. I will try other places today.
Does anyone have any further thoughts?
John
John Walton

Thanks Jim, I have the book you referenced. I'll check it out. My original seat was in unbelievably bad condition. It had three sets of covers on it. There was evidence of critters living in it, the spring set was rusted to powder in places, and the plywood was well on its way to returning to the ground that it came from.

I replaced the plywood and used some foam rubber to bolster the seat back along side the taller springs on the sides and in the middle. I had to replace some of the coiled spring thing around the outside. I just went to the hardware store and bought the longest, flimsiest, spring that I could find of the correct diameter. I stretched it out to about what the original was and locked it I place with hog rings and some stainless wire. I also had to cobble the chicken wire covering over the spring coils together with the stainless wire because the mesh had rusted away. I didn't have any burlap to cover it with so I made do with a piece of leftover upholstery material from another project.

My trial sit down in it revealed that the springs had lost enough tension that I could easily get my back to hit the plywood (either that, or I'm a tad bit larger than the average driver of the 1950's). So, I'll add some inch thick foam over the whole thing before I finally cover it with the Moss cover.

John, I'll try to make a diagram for you of what spring lengths go where this afternoon. It may not be completely correct due to the sad state of my original spring back, but I'll do the best that I can.

Kirk
Kirk Trigg

As I have only a few remnant rusted springs and no base, I am going to use modern upholstery foam for the seat back. Although it will not be original, I believe it will give a better ride.
Stuart
Stuart Duncan

Stuart,

I gave that option quite a bit of consideration. I eventually decided to use the springs simply because I had no confidence in my ability to do an adequate job of shaping the foam.

John, here is my best shot at identifying what length springs go where. Keep in mind that nothing about this drawing is to scale, it's just to give the locations of long, mid, or short length springs. It was as hard to be certain of the lengths as I was afraid it would be due to the poor state of my spring back.

Kirk Trigg

Kirk,
Together with the information sent by Jim B, Kirk, Stuart and yourself I believe I have all the information I now require.
Thank you all for your help.
John...Sydney
John Walton

John as I'll be turning my attention to the seats in a few months time could you perhaps post some pics of your progress & the details of the springs you managed to source. I have a seat back which was in good condition structurally prior to being recovered with vinyl in 1969 (rather badly but based on the original leather) & stored since 1971. It would be very original under the covering. You are welcome to borrow it if you think it may help you source items similar to those used originally. Cheers
Peter TD 5801
P Hehir

Peter,
I have misplaced your phone number could you give me a call this evening if convenient.
John.
John Walton

It has been very difficult to find a spring manufacturer or a supplier for the back seat springs.
Daley upholstery supplies in Villawood New South Wales can supply 4",6",8" and 10" in 10 gauge however they are the wrong shape having identical diameters at each end and a small diameter in the centre of the spring. Where the original spring is conical over it's full length.
Because of the lack of supply a friend of mine made his own springs. He obtained the correct 10 gauge wire and rolled it by hand into the original shape including the number of coils then tempered each spring. The wire is easily wound but once tempered it will have the characteristics of the original. The tempering is done by placing the spring or springs in you wife's oven ( when she is out for the afternoon) for twenty minutes at a temperature of 200 deg. Celsius.

John
John Walton

John

Dont know if you have tried this, talk with a mattress manufacturer they may be able to assist.
G Evans

G Evans suggestion, just above, is right on.
When I took my seat apart I found this stuck to the spring. I had posted it before.
The original manufacturer was a mattress company.

Jim B.

JA Benjamin

I have some mattress springs, however they are too strong and the wire gauge being thicker. Mattress springs are required to sustain various body weights over longer period of time where a seat back does not. Therefore the spring rate required for a seat back is lower.
I feel I have two alternatives. One is to obtain the wire and roll my own springs and the second is to use foam.
I called on a foam supplier yesterday and they can form and supply the correct density foam to suit.
I think this is the way I may go.

Thank you all for your help and suggestions.

John
John Walton

When I restored my TD back in 1977 my springs had turned to rust-dust. Replaced all the padding in the seat back with upholstery foam and it has been serving me well for 37 years.
John Quilter (TD8986)

Thank you John,
I feel this is my best solution.
John
John Walton

If you still have the box spring assembly, it attached to the backboard with a series of leather loops to act as hinges, with felt behind to cut the rattle. The factory used bits of leather left over from upholstery, I cut up a leather glove. Although my springs were in great shape, my wood had dry rot, so I fabricated a new backboard.

The picture is from my website. Thanks very kindly for including the word 'great' in the description of my photos, John. I'm always humbled that people find them so useful.

Warmly,
dave

Dave Braun

As an additional thought, I would find an overstuffed wing chair, and steal the coils from that, rather than a bed.

Warmly,
dave
Dave Braun

This thread was discussed between 15/11/2014 and 19/11/2014

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