Spindle pin removal tool survey

[Jeff G 78]

Thanks Lee. Let me know what kind of feedback you get from ZCOT members.

A cross-drilled hole would be a simple add to install/remove the rod from the spindle pin. Depending on the amount of space left beyond the nut once the tool is attached, the hole location might be best at the far right end as you look at the drawing. That way, the rod could be installed/removed with or without the pipe in place and the hole could be used to hang the tool on the wall for storage.

[Z-Engineer]

Jeff,

I am one of the CZOT members (engineer) working on the redesign of a puller that we had been using. The threaded 1" stud made of mild steel finally gave out on a puller I have had for a while that was purchased on eBay. A second one owned by another member removed over twenty spindle pins over the last several years and is beginning to wear out. When the threads on mine stripped out, I had the other end drilled and tapped. The machinist stated my stud was made out of butter and that it had a limited use. I was told to get some "real steel" and come back. We researched over the winter and tried to find a threaded steel stud equivalent to a Grade 8 bolt. ASTM A193 Grade B7 01 is what we ordered and sent to the machine shop to be drilled and tapped. I picked up two of the four threaded studs today and gave the machinist an additional $50 for the broken/dulled drill bits and taps. These 1" treaded studs are 12" and 3/4" longer than what were using (and should outlast the owners). They are very hard steel. I just need to verify that the additional 3/4" in length will leave enough room to remove pins with the A-arms still installed in the cars. This puller will function without having to neck down the 1" stud. The 1.5" nuts used to pull the stud and pin require a 1.5" open end or gear wrench. I have both which totaled about $100 for the wrenches alone.

The preparation and rate of the extraction are the critical parts of pin removal. Penetrating oil applied a week or more in advance helps the pin break free during the extraction process. The slow removal of the pin is what will make the extraction successful. As a pin is being pulled, the metal yields or stretches until the pin moves as a whole. If you crank on it too fast, the pin yields to the point of failure and the end comes off the pin. Been there, done that. The amount of deformation to the pin where the key locks it in place is another obstacle in the removal process. If the key is too tight, it deforms the pin and you have to pull the deformed pin out which can be difficult. Too get the pin moving, a lug nut can be treaded the opposite end of the pin. Once the pin is under tension from the extractor, tap on the lug nut to assist in breaking the pin free from the corrosion of the last thirty or forty years. It should start moving. Just make sure you go slowly. A gear wrench makes extraction easier, but it also allows you to try to remove the pin too fast. If it is not moving and you keep wrenching, the pin will break. Yep, that's what happened the first time we tried the gear wrench on a really stuck unlubricated pin.

Now that I have the new treaded studs, I will photograph and post all of the information needed to construct what we have done. The old one worked great. This new one will work better. Keep in mind that this was constructed to last and is not cheap to assemble.

Steve

[Jeff G 78]

Thanks for the info Steve.

What type of threads did you go with on the stud (all-thread) and what pitch? What type of thrust bearing are you using?

As for the big wrench needed, I thought about taking a cheap black oxide 1-1/2" (1-5/8" for acme) socket and cutting it in half to remove the square drive so it can slide over the 1" all-thread. The socket could then be made into a jumbo wing nut with some spare steel and some welding. It would be cheaper than a wrench and, if designed right, would be easier to use.

Please post the pics of your new puller when you can.

[Captain Obvious]

I was picturing the use of this tool earlier today and thinking that it might be nice to have some kind of feature that you could use to steady the device with one hand while you were turning the big nut with the other? So you aren't side loading the spindle tip as you tightened the nut?

I guess you could just push on the spacer tube with one hand while you pull on the wrench with the other, but I'm not sure how effective this would be.

I'm just thinking that cranking on that big nut with one hand out in space a foot away from the spindle tip pictures a little off. Might be better if you could translate all of that side load directly into rotation and tension while you were tightening the nut?

I'm having a hard time putting this into words, so I'll offer up an analogy... Kinda the same reason it feels fine using a ratchet with just one hand if you've got no extension on it, but if you put a foot long extension on it you feel the need to grab the back of the ratchet head with one hand while you crank the handle with the other. Does that make sense?

[GreenZZZ]

Jeff,

I am one of the CZOT members (engineer) working on the redesign of a puller that we had been using. The threaded 1" stud made of mild steel finally gave out on a puller I have had for a while that was purchased on eBay. A second one owned by another member removed over twenty spindle pins over the last several years and is beginning to wear out.

Fantastic first post Steve... Wow. Wonder if the 2nd one is my old puller. If it is, glad its fixing Z's instead of laying around my place. Check out Jeff's old skool auto-cad drawing on post #59!

[Z-Engineer]

The all thread stud has a 1-8 thread, which matches the nuts on the original puller. We use two nuts locked together to remove the stud from the pin because sometimes the force it takes to extract the pin tightens the stud/pin connection to the point it is difficult to break free. Flat washers were added as well to distribute load and assist with reducing friction between components. The concept of using a 1" diameter treaded stud also addressed the amount of force it can take to remove a pin. The large diameter stud has an increased amount of treaded surface area in contact with the nut to distribute the force to remove a really stuck pin. The size of the stud and nut eliminate them as a source of mechanical failure during the extraction process. The pin is the weakest link with this type of puller.

Your idea of a giant wing nut may work, but some pins have been so corroded in place that it sounds like a rifle shot every time you turn the wrench. The length of the handle becomes important to provide a large enough moment of force to turn the nut. Pipe wrenches or large crescent wrenches can work as well. We just pull enough pins in our club that having the gear wrench and an additional open-end wrench allow the nuts to be tightened enough to break free of the pin if the connection is too tight while making the whole set up easy to use. We are drilling and tapping both ends of the stud in the event that the end of a pin breaks off in the stud while being pulled. If that happens, we just use the other end of the stud to pull the other pin. It may not happen often, but it has happened. The strut and A-arm assembly is removed to deal with a pin that has had the end pulled off.

[Diseazd]

Jeff....Looks like you used a Weems Lettering Guide (). We used those back in the days at Georgia Tech in our engineering drawing classes. Can't wait to see the finished product.

[Jeff G 78]

I am very familiar with the "rifle shot" sound. In one of my posts above I describe the pin movement exactly as a rifle shot. It scared the crap out of us the first time we heard it. We were in a fairly small room that held the lathes, mills, and presses and the "rifle shot" echoed off the concrete block walls.

I think I will drill and tap both ends as well. That's a good idea and will make it easier to finish the job if a pin does break. Stopping in the middle of the extraction to drill out the broken pin doesn't sound like fun.

[Jeff G 78]

Jeff....Looks like you used a Weems Lettering Guide (). We used those back in the days at Georgia Tech in our engineering drawing classes. Can't wait to see the finished product.

OMG... Weems Lettering Guide! I haven't heard that term in 25 years. That said, I still have one and just saw it when I was fishing around in my old drafting supplies to find pencils and triangles to make my first puller drawing. .

For those young guys who have no idea what we are talking about, here is a lettering guide. I just looked and mine is an Ames. BTW Guy, No, I didn't use it. I did it freehand.

Edited May 11, 2012 by Jeff G 78

[Diseazd]

Me too Jeff......

[Z-Engineer]

To reply to Captain Obvious observation, "I'm just thinking that cranking on that big nut with one hand out in space a foot away from the spindle tip pictures a little off. Might be better if you could translate all of that side load directly into rotation and tension while you were tightening the nut?"

At first the concept of having a puller extend a foot back in line with the pin and placing a perpendicular moment force 20" or more seems a little odd, but when you start to consider that you have made a mechanical connection to the strut assembly and A-arm, and note that the structure itself is subjected to large lateral loads (reference to my style of driving) well beyond that to remove the pin, the applied rotation force does not have a major impact to the structure. While the length of the wrench applies the force, the rotational force is being applied where the treads of the nut meet the threads of the stud. Therefore, you really are applying the load directly into rotation and tension while you were tightening the nut.

Once the extraction assembly is connected to the pin, you have a very firm platform to apply the torque needed to remove the pin. It is pulled so tight onto the side of the A-arm that you do not have to support the extractor assembly during pin removal. It is as if it were part of the car.

I hope I addressed your concern. Please let me know if I just total missed what you are trying to convey.

[Jeff G 78]

Steve, be sure to upload pics of your latest puller when you get a chance. Thanks.