shortening piston pins?

rod · 03-24-2011, 05:10 PM

for a particular reason i need to shorten my pins .082". i know pins are very hard.
there are no 'off the shelf' pins this size. and i believe this could be done cheaper than buy custom new ones.

any idea how this could be done easily?

thanks rod in AZ

Rich Biebel · 03-24-2011, 07:31 PM

A carbide tool bit in a lathe will cut them.....

OR....

possibly if they fit......the tipping wheel on a valve facer could be used to shorten them. Would be a tedious little operation but I think I've done it.....

Rick Leininger Jr. · 03-24-2011, 07:47 PM

Go only about .010" at a time, and keep the same deburr or chamfer that was on the pin to begin with.

dwydendorf · 03-24-2011, 07:59 PM

The best way would be to grind them on a surface grinder in a precision V-block.

BillK · 03-24-2011, 08:29 PM

Rod,

Whichever way you decide to shorten them, keep in mind that depending on the type of lock that your piston uses, you may have to be very careful to match the chamfer on the end of the pin. Spiral locks require a straight end with virtually no chamfer but a lot of the newer pistons use a round wire lock that depends on the chamfer to force the wire into its groove as the pin tries to move from side to side.

Of course if the pins are press fit into the rod, then none of this matters

Ed Wright · 03-24-2011, 10:49 PM

Quote:

Originally Posted by Rich Biebel

A carbide tool bit in a lathe will cut them.....

OR....

possibly if they fit......the tipping wheel on a valve facer could be used to shorten them. Would be a tedious little operation but I think I've done it.....

I've done it with a valve machine. Is slow.

Adger Smith · 03-24-2011, 11:23 PM

Keep'em cool

Curmudgeon · 03-27-2011, 05:50 PM

Go to any Tool and Die Shop,its an everyday operation like sharpening punches . Best way is block and stack on wet grinder. Best to also give them the length you need instead of just telling them to take 40 off each end. Make sure to have each end ground by half instead of all off one end. Could also ask to have END Rockwelled before and after grinding. Carbide facing will work, but MUST be FLOODED with coolant to prevent softening end where lock rubs. Good luck,hope I was helpful.

03-24-2011, 05:10 PM	#1
rod Member Join Date: Dec 2009 Location: Kingman, NW AZ. in the middle of the longest stretch of Route 66 Posts: 313 Likes: 0 Liked 20 Times in 15 Posts	shortening piston pins? for a particular reason i need to shorten my pins .082". i know pins are very hard. there are no 'off the shelf' pins this size. and i believe this could be done cheaper than buy custom new ones. any idea how this could be done easily? thanks rod in AZ

03-24-2011, 07:31 PM	#2
Rich Biebel VIP Member Join Date: Jun 2007 Location: Northern New Jersey suburbs Posts: 2,314 Likes: 25 Liked 544 Times in 213 Posts	Re: shortening piston pins? A carbide tool bit in a lathe will cut them..... OR.... possibly if they fit......the tipping wheel on a valve facer could be used to shorten them. Would be a tedious little operation but I think I've done it..... __________________ Rich Biebel S/C 1479 Stock 147R

03-24-2011, 07:47 PM	#3
Rick Leininger Jr. Member Join Date: Jun 2007 Posts: 162 Likes: 0 Liked 0 Times in 0 Posts	Re: shortening piston pins? Go only about .010" at a time, and keep the same deburr or chamfer that was on the pin to begin with.

03-24-2011, 07:59 PM	#4
dwydendorf Member Join Date: Jul 2006 Location: michigan Posts: 162 Likes: 251 Liked 19 Times in 7 Posts	Re: shortening piston pins? The best way would be to grind them on a surface grinder in a precision V-block. __________________ ss/gt 93 t-bird

03-24-2011, 08:29 PM	#5
BillK Member Join Date: Nov 2005 Location: Waldorf Md Posts: 230 Likes: 12 Liked 30 Times in 17 Posts	Re: shortening piston pins? Rod, Whichever way you decide to shorten them, keep in mind that depending on the type of lock that your piston uses, you may have to be very careful to match the chamfer on the end of the pin. Spiral locks require a straight end with virtually no chamfer but a lot of the newer pistons use a round wire lock that depends on the chamfer to force the wire into its groove as the pin tries to move from side to side. Of course if the pins are press fit into the rod, then none of this matters __________________ Bill Koustenis

03-24-2011, 11:23 PM	#7
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: shortening piston pins? Keep'em cool __________________ Adger Smith (Former SS)

03-27-2011, 05:50 PM	#8
Curmudgeon Junior Member Join Date: Jan 2011 Location: Asheville,N.C. Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: shortening piston pins? Go to any Tool and Die Shop,its an everyday operation like sharpening punches . Best way is block and stack on wet grinder. Best to also give them the length you need instead of just telling them to take 40 off each end. Make sure to have each end ground by half instead of all off one end. Could also ask to have END Rockwelled before and after grinding. Carbide facing will work, but MUST be FLOODED with coolant to prevent softening end where lock rubs. Good luck,hope I was helpful.