12 Point Spider Screws

Bamban

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Over the years I have used every available screws for the spiders, all of them are cumbersome to adjust especially the outboard ones.

Last week when I was doing some rearranging and cleaning in the garage I ran across an old package of ARP bolts from Summit Engineering, left over from my racing days. Guess what they are 3/8x24, the same screws I use on the outboard spiders and on a couple spiders up front. I remember how easy it was to use those 12 point wrenches on those ARP bolts. Off to McMaster-Carr to see of they have the 12 point screws/bolts in the sizes I need.

Late last week the shipment from McM-C came in and I proceeded to modify them for the application. Using 12 point wrenches is so much easier than indexing the allen wrenches on set screws or socket heads.

I used a barrel drop to make a jig to hold the 1 inch screws. Drilled and tapped it 3/8x24.

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We use these in only place in the plant . Clamps that hold our dies straight . Very limited space to get the hex keys into the right orientation . We all have to carry that special 5/16 12 point wrench around with us , can't tell you how many I've lost in 2 years . :grin:
 
Over the next couple of weeks or so my front spiders are all getting the 12 point screws, even the 1/2-20 ones. The outboard ones on three lathes have been converted.

I don't know why I did not think of the 12 points earlier on.

Aukai, that's a nice supply and selections of ARP bolts.
 
Hey Nez,

Nice idea, I would add some thin threaded locking rings to prevent the bolts from loosing and going flying. Forgot to lock mine down one time and one took off. Alternative is to remove them when not in use.
Mark
 
Hey Nez,

Nice idea, I would add some thin threaded locking rings to prevent the bolts from loosing and going flying. Forgot to lock mine down one time and one took off. Alternative is to remove them when not in use.
Mark

Mark,

Thank you. I saw some thin 3/8x24 from McM-C sometime ago, they refer to them as jam nuts I think. I will look for them and order a bag.

Nez

Found them.

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I used 3/8 x fine 12-pts from McMaster (affordable by the box) for my 'smithing fixtures. Holes are counterbored and I cut down a deep socket to make what I call a "shell socket" to reach into the counterbores. Shell socket lives with my chuck wrench.
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