I would like to find out from some of the more experienced users in here whether or not using a spinner nut on a threaded rod as a means of attaching the prop to the hub is as safe as using just a hex bolt.They work just fine on glow engines so I can't see a reason why they shouldn't work well on these gassers.I'm worried about the degree of potential kick back and any safety concerns that may arise from such an incident.The main reason for going this route is to allow me to get more purchase on the crank to make it easier to turn over with my 18 volt cordless and Sullivan starter hub assembly that I use.It also helps keep the starter cone in one fixed location minimizing both vibration and any potential for starting accidents.I was thinking of Loctiting the rod into the prop hub assembly and just tighten the prop onto the rod using a 5/16"-24 safety spinner/nut and a through metal rod.Would this suffice?Any other ideas on this mostly gladly welcomed.Thanks guy's!

No worries, it will work fine. I recommend however, that you use a grade 5 or better bolt to make your stud. The threaded rod you buy at hardware stores is often of pretty questionable quality. Just pick up a grade 5 bolt that is long enough, and cut off what you need. Be sure to dress up the threads nicely after cutting so that it doesn't shred your prop adapter or safety nut threads.

AV8TOR

Thanks AV8TOR for the reply.I was wondering about the strength of threaded rod myself earlier.Your right that it is indeed rather bendable compared to any graded bolt.The problem with using a bolt though will be finding a bolt that has enough threaded length to it.Usually,you will find 5/16" bolts in various lengths at the fastener store but after a certain length(?),the threaded portion of the bolt doesn't get any longer,only the upper unthreaded neck portion does.It would be nice to have the rod thread deep enough into the prop adapter so that it butts up against the threaded crank portion.That way you know for sure that your indeed tightening down the spinner nut to the prop and not accidentally turning the threaded rod portion further into the prop hub.In which case,just how many threads would that spinner nut be engaging?A possible accident in the making?Maybe.I know that the Loctite would prevent the rod from turning but just how many tightenings and loosenings will it take before it comes loose.Thus the need to thread in as far as possible.I think what I'm looking for here is a 5/16"-24 automotive grade "stud".I'll have to measure the prop adapter internally for thread depth(installed on the engine) and see if there is a stud available that is long enough to do the trick.However,I may be wrong about this but I think most automotive grade studs that would be the correct length for this application,aren't fully threaded either.DOH!![:@].........

A long stud will often be unthreaded in the middle. No problem with this as thats where the prop will be. With a little carefull looking you can find one the right length and body.
If all else fails call Tru Turn and they will have a 5/16 bolt that is taped in the end for a 10/32 spinner bolt. Then you can use a Tru Turn spinner too.

Some auto parts stores will carry engine studs of that size and in various lenghts. Very strong and inexpensive. I know thatthe Napa down the street from my house does.

TKG,how does the spinner attach to the center drilled 5/16" bolt.I've seen these bolts before that are tapped 10-32 in the end of the hex but I've never actually seen one in use.Anybody got a picture of what this setup looks like?Do you tighten down the bolt first and then attach the spinner nut to the hex head with a 10-32 stud or something?A picture truly is worth a thouisand words at times like this.

Dr.Evil,will try the NAPA down the road tomorrow to see what sizes of studs that they carry.Thanks!

With the spinners TKG is talking about, you don't use a spinner nut or safety nut. The bolts or studs with the hole drilled and tapped in the center are for full size spinners. A long thin screw goes through the center of the full size spinner at the point, and into the small tapped hole to hold the spinner on.

As the others have said, you should be able to find a stud, and if it doesn't have threads where the prop rides, that's fine. Don't worry so much about it all coming loose. If you use some red loctite on clean threads, tighten it all down well, and let it sit until the loctite dries you'll never have a problem. It's not really necessary for your stud to tighten up tight against the crank as long as it has plenty of threads into your adapter. This setup will actually be stronger than just using a bolt.

Good luck,
AV8TOR

MOST GOOD INDUSTRIAL SUPPLY HOUSES WILL CARRY TREADED ROD IN "GRADE 5" AND "GRADE 8" EITHER ONE IS GOOD JUST DONT USE THE "HARDWARE GRADE" FROM A HARDWARE STORE

IVE BEEN THINKING BOUT THIS SOME AND YOU COULD ALSO USE A LONG ALLEN SETSCREW, I OFTEN REPLACE BOLTS IN SB CHEVY RACING ENGINES WITH THEM TO USE AS STUDS. ANOTHER THOUGHT ABOUT THE SPINNER ATTACHMENT, SOME USE A LONG NUT THAT IS TAPED FROM BOTH SIDES WITH DIFFERENT THREADS. ONE HOLDS THE PROP ON AND THE OTHER SIDE IS SMALLER TO ACCEPT A LONG SCREW TO HOLD THE SPINNER ON.
FARMER TED

Just what type of nut is being referred to here?

Such a variety of types as this site lists near the page bottom.
http://www.tcnj.edu/~rgraham/barrett/manual1-A.html

Hi Mike,the spinner nut that I'm planning on using is a Dubro #731.It has a larger surface area than the Higley safety spinner nut giving the starter cone more area to grip when turning it over.Here's a listing for Dubro's on-line catalogue.Check out page-52 to see what I'm referring to.

I couldn't find a bolt with enough thread length or a proper automotive type stud that would suffice at any of my local fastener shops so I settled on 5/16"-24 threaded rod which I'm told has a grade of "B7".He said that the rod was an alloy.I've never heard of this grade rating before but I'm told that it is stronger than a grade 5 but not as strong as a grade 8.I'll be cutting it to the required length and Loctiting it into the prop hub assembly probably with red Loctite.The Dubro spinner nut will hold the prop on the threaded rod portion and it will most likely be Loctited on with blue Loctite.Whether Loctite is necessary on the spinner nut or not I'm not to sure of as my Thunder Tiger 1.20 turns this 16x8 a lot faster than this Homelite ever will and I've never had the spinner nut loosen off of it at any point.This should work just fine..........hopefully.

http://dubro.com/DUBRO2005CATALOG/index.htm