drilling leaf springs (FAQ) (1 Viewer)

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Ok I just finished my own saga trying to drill lhrough leaf springs to use the CCOT spring pins.

I am no machinist but have drilled my fair share of holes in all thicknesses of steel. I'll say right now, there is no way that a normal high speed OR a cobalt drill bit will drill through the springs that I have. They are supposed to be from a 1976 FJ40.

No drill press but I did clamp the spring in a vise, used oil and low speed with a brand new split point cobalt bit and a freshly Drill Doctor sharpened and split point high speed steel bit.

In both cases the drill bit would not even get a good bite on the steel. Just to make sure I didn't have two poorly ground bits I used them to drill into a piece of mild steel plate with no problem. Nice curling as the bits cut into it. So I know they are sharpened correctly.

A concrete bit had slightly better luck and I eventually got through one spring. Great 10 minutes to get through ONE! 13 more to go? I don't think so...
 
That being said I offer the following for anyone trying to drill out the srpings to use bigger pins: Save your energy and instead make your own spring pins to fit the existing holes! The head of the pin is usually the wrong size for the spring perch hole. I have three sets of pins with three different size heads. See first pic. I looked through the scrap heap and found a piece of rod that was close to the size of the hole in the axle spring perch and cut off two pieces the same height as the ones on the springs I took off. I welded these to 4" lengths of 7/16" all thread. Took all of an hour to make 2 pins, half spent that trying to figure out a good way to get the all thread square to the head. Magnets to the rescue!

Anyway there is my solution. When I get a drill press the first thing I will try is to drill through the old springs...
Spring4.jpg
Spring5.jpg
Spring6.jpg
 
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ive never had to drill a spring always found the right size cap screw to do the job .they come in metric and american threads all sizes and lenghts good luck
 
X2

You need a carbide bit to cut spring steel. A carbide masonary bit works well.

Masonry bit will do it. Slow speed medium down pressure with marvels mystery oil as a lubricant. Clamp the springs down good. When it bites it will try to spin the whole damned spring and knock everything off the workbench. If you drill too fast and too hard it will actually heat harden the spring steel and make it more difficult to drill.
 
Sounds like a lot of fuss over nothing to me. I've lost **** of how many springs I've drilled. Plain steel drill bits are just fine. You don't need any special bit. You do need a drill press, not a hand drill. Clamp it into the drill press and any cheap bit will go though it in no time.

If your trying to push a bit through with a hand drill, that's another story. Fairly frustrating. Don't do it. ;)


Mark...
 
Mine worked fine with a Cheep harbor freight drill press, Masonary Bit from Home depot

it took some time, but worked just fine! and i was drilling new holes, thru 12 leaves!
 
I used a 3/8 ball nosed rotary file in a hand drill motor-slow speed with cutting oil and it worked great!
 
What size bit are you using? Maybe your trying to drill too big a hole. Not only did I use a hand drill but I kept the whole pack together and did them all at once. Lots of fluid, pressure, slow speed and some crappy bit I had laying around; 3/8 I believe. I only have a few bits that cost more than $5. Good luck.
 
Mark -

You are drilling too many spring packs if...

I've lost **** of how many springs I've drilled.

Take it easy! It's not worth it!

Rocky
 
Just completed drilling the mil. wrap leafs only. Used an 1/8th inch cobalt drill pit and stepped up in size an 1/8th inch at a time till the appropriate size was attained. Used a cordless drill on the lowest speed and applied cutting wax to the bit tips. With the equipment noted and application of moderate pressure no issues arose. 35 minutes to disassemble drill and reassemble two spring packs.
 
I have had really good success with round tip carbide tool in my die grinder .
 
Hi All:

I've used a "Uni-bit" in a $100 drill press set at the lowest speed (about 200 RPM) with lots of cutting oil without much trouble to drill through spring leaves.

Regards,

Alan
 
hey 'm havin fj 43 ,and looking for coil spring conversion,need ideas and pics pls,m using this to day to day and bit of off road too
 

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