Set screw completely stripped

[Chris1055 106]

I was going to pull the engine drive pulley off the c160 because all of the bolts for the clutch plate are broken off inside. The first set screw was fine and was impressed how easy it was. Put the Allen in the other one and it just spins. What's the best route in removing the set screw and getting that pulley off

[WVHillbilly520H 10,376]

Are the threads stripped or just the sunken Allen hex and your wrench is spinning inside it? If the latter sometimes an "easyout" in the stripped hex will grab and spin it out or try the next size Allen key and tap in with a hammer works as well if not to tight, Jeff.

[ol550 830]

I have used torx bits to get stripped allen hex screws out.  May have to drive it in also.  Cobalt drill bit at very slow speed as a final attempt.

[cleat 7,132]

I have resorted to just pulling pulleys off with the set screws still tight.

At least you got one out.

 

Once the pulley is off the shaft, the set screw may be looser.

 

You will need a good puller to do this and you may mar the shaft a bit but it will clean up.

 

 

[953 nut 58,697]

Set screws are hardened steel and if you need to drill it out they are best drilled with a Carbide tipped bit.

 

These carbide tipped drills are ideal for locksmiths, auto mechanics or any operator drilling into hardened steel.  Can be used to drill out broken bolts, studs, taps and drill bits.  They also cut hard steel such as safes, bearing races and dies. The carbide is designed to prevent chipping and dissipate heat quickly. These drills are designed solely for use in hardened steel and perform poorly in softer materials.               Carbide Tipped Drills for Hardened Steel Size Flute Length Overall Length Shank Diameter Stock Number 1/8 1-1/2 2-3/4 1/8 CT7050125 5/32 1-7/8 3 5/32 CT7050156 11/64 1-7/8 3 11/64 CT7050171 3/16 1-7/8 3 3/16 CT7050187 7/32 2-1/2 4 7/32 CT7050218 1/4 2-1/2 4 1/4 CT7050250 1/4 4-1/4 6 1/4 CT70502506 9/32 2-1/2 4 9/32 CT7050281 5/16 2-1/2 4 1/4 CT7050312 5/16 4-1/4 6 5/16 CT70503126 3/8 4 6 3/8 CT7050375 7/16 4 6 3/8 CT7050437 1/2 4 6 1/2 CT7050500 9/16 4 6 1/2 CT7050562 5/8 4 6 1/2 CT7050625                     * - For non-production drilling of             hardened steel

These drills require moderate operating pressure, and a low spindle speed. You can use oil as a lubricant and coolant. Using these drills in a hand drill may be un-avoidable in some situations but stationary equipment is always preferred for carbide tipped tooling. Unfortunately, there is no easy way to tell one metal type from another just by looking. Hardened steel is always significantly harder than other steels. It is resistant to filing, which means a file will take off much less material from hardened steel than regular steel. It is difficult for even a trained, experienced craftsman to differentiate between steel types. We use a combination of 60 years of experience and a process of elimination to determine if the drills for hardened steel are needed. Sheet steel is almost never hardened (safes being an exception). Bar stock is also almost never hardened. Bolts, screws, freeze plugs, bearing races, safes, shafts, gears, and industrial machinery parts are examples of hardened tooling. These drills are most often used as a last resort, for removing other broken tooling from the boring site, or if other high quality drills have failed to effectively drill a given material. http://wlfuller.com/html/drills_for_hardened_steel.html

[shallowwatersailor 3,214]

I had to remove a rounded lug bolt one time. I decided to drill it out by starting with a smaller bit with oil just to to provide some relief and a path for the next size to follow. It loosened enough with the next bit that I was then able to just turn it out with a socket. It took a while but I got it out.

[WVHillbilly520H 10,376]

21 hours ago, 953 nut said:

Set screws are hardened steel and if you need to drill it out they are best drilled with a Carbide tipped bit.

 

These carbide tipped drills are ideal for locksmiths, auto mechanics or any operator drilling into hardened steel.  Can be used to drill out broken bolts, studs, taps and drill bits.  They also cut hard steel such as safes, bearing races and dies. The carbide is designed to prevent chipping and dissipate heat quickly. These drills are designed solely for use in hardened steel and perform poorly in softer materials.               Carbide Tipped Drills for Hardened Steel Size Flute Length Overall Length Shank Diameter Stock Number 1/8 1-1/2 2-3/4 1/8 CT7050125 5/32 1-7/8 3 5/32 CT7050156 11/64 1-7/8 3 11/64 CT7050171 3/16 1-7/8 3 3/16 CT7050187 7/32 2-1/2 4 7/32 CT7050218 1/4 2-1/2 4 1/4 CT7050250 1/4 4-1/4 6 1/4 CT70502506 9/32 2-1/2 4 9/32 CT7050281 5/16 2-1/2 4 1/4 CT7050312 5/16 4-1/4 6 5/16 CT70503126 3/8 4 6 3/8 CT7050375 7/16 4 6 3/8 CT7050437 1/2 4 6 1/2 CT7050500 9/16 4 6 1/2 CT7050562 5/8 4 6 1/2 CT7050625                     * - For non-production drilling of             hardened steel

These drills require moderate operating pressure, and a low spindle speed. You can use oil as a lubricant and coolant. Using these drills in a hand drill may be un-avoidable in some situations but stationary equipment is always preferred for carbide tipped tooling. Unfortunately, there is no easy way to tell one metal type from another just by looking. Hardened steel is always significantly harder than other steels. It is resistant to filing, which means a file will take off much less material from hardened steel than regular steel. It is difficult for even a trained, experienced craftsman to differentiate between steel types. We use a combination of 60 years of experience and a process of elimination to determine if the drills for hardened steel are needed. Sheet steel is almost never hardened (safes being an exception). Bar stock is also almost never hardened. Bolts, screws, freeze plugs, bearing races, safes, shafts, gears, and industrial machinery parts are examples of hardened tooling. These drills are most often used as a last resort, for removing other broken tooling from the boring site, or if other high quality drills have failed to effectively drill a given material. http://wlfuller.com/html/drills_for_hardened_steel.html

We use solid carbide twist drills at work quite often dealing with hardened tooling, but be advised that they will shatter faster than a good high quality high speed steel bit, even I'm a milling machine used as a drill press, Jeff.

[R. L. Addison 299]

Don't know if you got the set screw out or not, I have used metric wrenches just a little bigger than the standard design size, and driven them in lightly (if there is such thing) and they come out easily. Might want to soak it first. Also, I have run into standard screws with metric hexes (?) which can throw a person for quite a loop when not expected. It may also be cleaned and use some lock-tite to break it loose in some cases, but i would want to be sure there was room enough to swing the wrench or able to get it out.

[Searcher60 209]

Use a pinch block with a puller and force it off. Get screw out then. Note that is a pricey pulley for the C-160 automatic.