Removing a Dowel Pin

[matthewsx]

One thing that has worked for me is a big pair of side cutters.

Basically grab the pin closest to the hinge and find something that will protect the workpiece and serve as a fulcrum. Have removed many stubborn pins this way since the side cutters can get a better grip on it than vise grips.

John

 

[markba633csi]

If you can grind 180 degree flats on it then I would apply vise grips and twist and pull- may not even need the flats

 

[SLK001]

I would assume that the pin(s) are hardened. Attach a pair of vise-grips as tight as you can to a pin, leaving room for a pry bar of sorts to fit underneath the grips. Pry up, repeat as necessary.

 

[rwm]

You guys are a great resource!
I'm gonna start out with the vice grips and report back. I do not know if these pins are hardened. I will try scratching one with the file first. I failed to add that these are metric pins. Do I need to use metric vice grips?

 

[piper184]

Apply heat to the base material. If there is any locking compound, heat above about 450F should compromise the compound. Also the base metal will expand away from the pin making it easier to pull out.

 

[projectnut]

Most all dowel pins are case hardened to a minimum of Rockwell C60. The case hardening usually extends .030" deep. The main body is hardened to a minimum of Rockwell C47 but can be as high as C58.

 

[RJSakowski]

I have pulled dowel pins with only 1/4" extending from aluminum outboard engine blocks with Vise Grips. Use a pair whose serrations are fresh and tighten the snot out of the Vise Grips. The twisting motion will usually break the dowel free. Using side cutters will destroy them and you can't get the same amount of grip that you can with Vise Grips.You could cut a shallow groove just above the surface of your part and use the side cutters but you will probably still destroy them.

 

[Tom1948]

Sorry, I did not know it was a solid pin. I thought it was more of a thin wall locating dowel open in the center. They are used on motorcycles a lot.

 

[Pevehouse]

I need to remove two 1/4" dowel pins from A36 steel. I did not place these so I am not exactly sure of the interference. Assuming they are a standard interference fit, what is the best way to remove these? It is a small piece so it could go in the mill.

I could drill and tap the dowel pin for 10-32 and use a spacer and washer to apply traction.
I could TIG weld a section of 1/4" screw to the end of the pin and use similar technique
I could lock vise grips to the pin and use a BFH

Please advise. I have never attempted this before.

I have been in your shoes needing to remove a few from a crankshaft. There are dedicated tools on the market that use a collet style puller so a collet block and collet as mentioned above may suffice. The dedicated pullers are pretty pricey

 

[rwm]

These dowel pins are hardened. Vise grips will not budge them. I tried SAE and Metric.
Tomorrow is welding.
I cannot imagine a collet gripping these hard enough to move them.