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Sun Mar 09, 2008 11:09 am

I've spent a lot of time searching the forums for the best way to cut and assemble cut to length pushrods (for the do it yourselfer without special tools) and I decided to share what I learned.

My first attempt was with a mini tubing cutter. It worked fairly well but took a LONG time (about 20 min. each). Not so good by the time I was done with my second pushrod as the chromolly rods had seriously dulled the cutting wheel and it had a tendency to try and walk.

On my second attempt, I decided to try something that I read about here in the forums that seemed just crazy enough to work. boos-k_nb posted a couple years ago that he'd used a drill press and a hacksaw. I tried it--- chucked the pushrod in the press and let it protrude through the table hole and adjusted the table height plus the thickness of the hacksaw blade to my cut mark. Started the press and held the blade against the rod, using the table hole as a backbrace. The result was a perfect, clean cut on all remaining pushrods. A light dress up with a file and they were good to go.

For assembly the most popular method seemed to be using 2 old lifters to drive the pushrod ends in. Unfortunately, I had gotten rid of all my old lifters. Here's what I ended up doing: 2 scrap pieces of old 2X4 (about 6 inches long) turned on their side (the 2 part of the 2x4). Using the drill press, I drilled a 7/16" hole about three quarters of the way through the sides of both pieces of wood. Once the tip was started in the pushrod I applied a drop or 2 of blue Loctite for lubrication around the tip base (double advantage of security once cured). The 2x4's took the place of the lifters with the holes I drilled in them and used a hammer to smack the upper block with the lower block against the garage floor. Came out great.

For a pushrod measuring tool, I used an old chromolly pushrod, cut out about a 3/4" section, and threaded the I.D. of both rod halves 8mmx1.25- then used a new type 1 exhaust stud to reattatch the 2 pieces and make it adjustable.

I just wanted to share this experience with anyone else who may be wondering the same things I was, and maybe save somone a bunch of searching, trial and error, money, and maybe a few ruined pushrods!

Sun Mar 09, 2008 11:56 am

i chuck a pushrod up in my drill and use a tubing cutter to cut with while the drill is spinning.

Sun Mar 09, 2008 12:18 pm

By far the best way to cut pushrods, as it also has an adjustable stop to make sure each pushrod is cut exactly the same length.

Sun Mar 09, 2008 12:38 pm

Wow,that looks great,err what is it :oops:

Sun Mar 09, 2008 1:25 pm

That is a tool to cut arrows, I made one years ago. it use a cut off wheel, I used a die grinder mounted in wood blocks and held in place with hose clamps, and made a stop that slides on a piece of aluminum tube that would lock in place with a set screw. what kind of tolerances are we talking about when cutting pushrods? I hope thats what it is, dont want to sound like a know it all.

Casey

Mon Mar 10, 2008 6:41 am

earthquake wrote: That is a tool to cut arrows, I made one years ago. it use a cut off wheel, I used a die grinder mounted in wood blocks and held in place with hose clamps, and made a stop that slides on a piece of aluminum tube that would lock in place with a set screw. what kind of tolerances are we talking about when cutting pushrods? I hope thats what it is, dont want to sound like a know it all.

Casey

You nailed it. The one we use is NLA which is a bummer. At least you can buy the cutoff discs for it though.

Wed Mar 12, 2008 11:12 pm

I use a lathe for that operation. It is simpler with a collet chuck. Stick it in there and cut it off.

Of course you have to size them accordingly and chamfer cut the inside so the nipple will sit square.

Also, you cannot just cut whatever lenght you want. The "reamed areas" are only so long. So you want to make sure you still have the reamed areas for the ball stem. Otherwise, you will split the tubing when you press them in.

Thu Mar 13, 2008 5:48 am

"My" machinist used a lathe to turn mine down also. Said it was easier to turn down the lip to get the length than to come in from the side.

Going to remember this tip.
Quote: It is simpler with a collet chuck

Thu Mar 13, 2008 11:08 am

i use a tube cutter but with a blade for cutting stainless.

Thu Mar 13, 2008 1:10 pm

I used my mill. Using a lathe would be the best method but mine isn't working right now.

Tue Mar 18, 2008 12:44 pm

What tolerance would you expect to get from your local machinist if he did a set for you?

my last set were within a few thou, except for a couple that were +/- .020"

Jake says +/- .001", and that would be great,

But would YOU run a set with one .020 to long and a couple .020 too short?

it's just moving the screw around, right? :?

Tue Mar 18, 2008 12:53 pm

I have been using the "arrow cutter" that Eric posted for 9 years now.. Nothing gives the ease of cutting or more accurate results, including a Lathe.

Tue Mar 18, 2008 3:28 pm

lately, i have been using dual taper push rods, with my limited mind, and knowing i cant grab just the end because of the taper, i ended up grabbing the middle where it is parrellel and then use a spot face cutter with pilot to shorten mine. Just did another 8 about an hour ago like this. works like a champ so far.