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Spring Compressor


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19 minutes ago, John Morrison said:

 

Daz,

I,m away for the weekend but sure I have a spare.

Ifyou Don,t get sorted I take a dekko Monday.

John.

OK cheers John

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Daz

I agree with Harry.

If you decide to go for making one, get to your local Agricultural/Farm machinery shop (not a mower shop) and buy a 1m length of (I would suggest) M16 HT studding and suitable nuts/washers etc.

The only 'complex' part of the tool is the lower plate, which (probably) the farm shop will have something suitable (scrap metal plate) for use.

Grease the threads, and mind your fingers!!

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Don't worry, M12 is more than enought,

holds 5.000 kg without any problem,

easyer to turn the nut M12x1,75 than the M16x2,0,

and more does not fit on a TR2-4, if you will own one anytime.

Edited by Z320
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I too made my own.

I use 2 nuts at both ends, and let the 2nd nut “follow” on close distance. The thread in the nut can (will) wear out sooner that that of the threaded rod, and you will not notice this until.....

Safety always comes first.

And off course, it will fail when the force and stored energy are highest (spring fully compressed).

Waldi

 

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Did you realize the shock absorbers limit the decompression  of the coil spring on the TR4A-TR6?

And is only "M9.5" on its top end?

If you feel unsafe: I make and sell TR spring compressors.

The way they work very close to the original Churchill Tool - with a rocking steel plate. This works very smooth.

 

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On 10/11/2019 at 8:53 PM, harrytr5 said:

Make one out of 1/2" studding and steel plate. Save yourself money. So easy to make.

Regards Harry TR5 Nutter

Easy if you have the right size steel plate with a hole in the centre. Unfortunately I don't!

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M12 in 8.8 quality  is good enough,

at the DIY market you normaly only get the 4.6 "quality",

8.8 is marked yellow (at Germany), on the UK maybe different

Edited by Z320
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Find your local nut and bolt supplier they usually have lengths of metric high tensile rod/nuts. I used an old alternator pully/washer and two nuts on the bottom and washers and two nuts on the top worked fine front and back.

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The torque to lock a M12 bolt or nut with 8.8 quality is about 84 Nm.

With 84 Nm or less you never do a damage on the bolt/nut.

To compress the spring with a M12 bar/nut the torpue is much below 84 Nm.

So you use the M12 8.8 nut / bar much below their limit, never as much as "tight".

But if you feel better use M16 high tensile 10.9 ( max. 290 Nm) or 12.9 ( max. 354 Nm).

Edited by Z320
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For info - I made my compressor using 12mm screwed rod. It has worked faultlessly for several years. Just clean it after use, inspect it for any damage or deterioration and put it away until  you use again or more likely lend it to somebody else. When I made it I asked a Stess engineer colleague to calculate the stress involved using the spring rates and compressions involved in worst case TR application. He concluded that that using a commercial quality M12 bar was more than adequate and that even a M6 rod would be adequate to safely take the loads involved but with less margin for wear or damage. I see no reason to make one from anything larger, stronger, heavier or more expensive. 

Regards

Rog

 

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41 minutes ago, Icarus60 said:

For info - I made my compressor using 12mm screwed rod. It has worked faultlessly for several years. Just clean it after use, inspect it for any damage or deterioration and put it away until  you use again or more likely lend it to somebody else. When I made it I asked a Stess engineer colleague to calculate the stress involved using the spring rates and compressions involved in worst case TR application. He concluded that that using a commercial quality M12 bar was more than adequate and that even a M6 rod would be adequate to safely take the loads involved but with less margin for wear or damage. I see no reason to make one from anything larger, stronger, heavier or more expensive. 

Regards

Rog

 

+1

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Since we are all showing & telling how we compress our springs:

I used a Stainless steel M12 length of studding (because I had it already) with 1 nut at one end, welded to the studding, & two nuts at the other end welded to each other to make a double length one (more threads in contact with studding).

some suitable steel plates at either end, & jobs a goodn.  To use I put a ring spanner on the double nut (at the lower end, & an air powered ratchet socket driver on the single nut.

Bob.

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19 hours ago, Icarus60 said:

For info - I made my compressor using 12mm screwed rod. It has worked faultlessly for several years. Just clean it after use, inspect it for any damage or deterioration and put it away until  you use again or more likely lend it to somebody else. When I made it I asked a Stess engineer colleague to calculate the stress involved using the spring rates and compressions involved in worst case TR application. He concluded that that using a commercial quality M12 bar was more than adequate and that even a M6 rod would be adequate to safely take the loads involved but with less margin for wear or damage. I see no reason to make one from anything larger, stronger, heavier or more expensive. 

Regards

Rog

 

What size does the steel plate need to be? How thick?

Thx

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10 mm thick is fine, and say 80 mm wide (with a hole 15 mm or so in the middle).

It can probably be thinner/smaller, but that would require a calculation (for me at least).

Waldi

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1 hour ago, Waldi said:

10 mm thick is fine, and say 80 mm wide (with a hole 15 mm or so in the middle).

It can probably be thinner/smaller, but that would require a calculation (for me at least).

Waldi

Cheers Waldi

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Hi daz,

photo of my home made one, note the use of old front wheel bearings to help when things get tight.878758515_springcompreser006.jpg.83bd6db3fb4fbaf8592777ad6b78f962.jpg

I didn't use a plate on the base, but some 1 inch box, it has the advantages of not only not turning inside the four studs, but also its easier to handle and locate, also it is what I had lying around!

I can sort you out with my spare, it is slightly different in that it has a welded nut about 1.5 inches from the end, this goes into the top S/A hole, and a washer and nut on the top, clamps the whole thing up, letting the user just turn the bottom end.

Pm me an address.

John.

 

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21 hours ago, Waldi said:

10 mm thick is fine, and say 80 mm wide (with a hole 15 mm or so in the middle).

It can probably be thinner/smaller, but that would require a calculation (for me at least).

Waldi

I have used the spare wheels disc clamp 

Screen Shot 2019-10-15 at 10.51.37 PM.png

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Hi, this is my experience:

When you lift the car the threaded bar goes NOT through the steel plate (coil spring pan) in 90° angle - but clearly inclined.

This is why the drill in the steel plate must be bigger than the diameter of the threaded bar, and much more bigger with a more massiv steel plate.

P1000904-b.thumb.JPG.0349812b6d9c271976917dcc4debe155.JPG

Anyway you can not avoid the bar going sidewards and rasps on the steel plate? I only guess, I never did that!

In 2013 by accident (really, one of my front axle brackets ripped off) I was able to see a mechanic working with the original "Churchill Tool".

This has no steel plate but a "huge" steel ball, this slides in the spring pan while the spring pan moves upwards and to about a 90° angle.

The threaded bar never rasps on the steel ball. I've been very impressed!

 

I did not want to pay 169 GBP for one of them, so I made this: a steel plate, drilled diam. 20 mm and deep countersunk from both sides.

On the countersunk surface slides a stainless steel ball, drilled to the M12 bar. This works like on the original tool.

Very smooth, the steel bar never touches the steel plate, steel plate is fixed by the damper bolts, very safe and it lasts for ever.

P1000889-b.JPG.93ed7cba7af030ce89faea0ffc49d7e7.JPG

 I also did that for the Jag Mk2, some kind of different.

448422128_JaguarMk2steelplate.JPG.0d04f18e17de7ef833f082532f8ac431.JPG

To compress it comes with a standard hex nut 19 mm x 10 mm long (suits 3/4" spanner) and a extra long hex nut 17 mm x 40 mm (suits 5/8" spanners).

From time to time I make a small number of them, sell them at eBay but will finish with that (have other projects).

But feel free to make your own the same way.

I have no money interest, from the money I ask I have to go out with my wife to please here for the hours I spend in my workshop.

Ciao, Marco

Edited by Z320
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That's a nice tool, Marco.

To deal with that angle, I left the spring pan detached from the lower A arms, and pulled the pan up with the compressor. By the time the pan got to its final position, it was well aligned with the A arms for attachment.

SDC11419a.JPG

SDC11420a.JPG

 

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