Spirol Pin Part # and Bolts vs. Pins

[Planter Bob]

Does anybody know of the Spirol coiled spring pin part# that is sold to to Argo as their part #11145 pin?

I'm hesitant to buy a pin until I know what the shear strength is I want, and I'm thinking that Spirol may make a custom coil spring for the older Argo applications.

Argo wants $2 for each pin, but I can buy a 500 pack from Spirol (Part code CLDP .312X2.500 MBK) for only $125.79, assuming the standard pin is what Argo used. That works out to a tad over 25 cents a pin.

Hmmm....I wonder how long it would take me to break 500 pins?

I've also found them at Grainger (Item #5EB84), assuming I'd want the standard-duty pins with a double pin shear strength of 8,700 psi. Those pins are available in a pack of 25 for only $17.08. That's less than 69 cents a pin. More money per pin, plus I'd lose the "cool factor" of having a bag of 500 shear pins for my mid-80's Argo.

No...I don't want to to to bolts. I just stripped down my second mid-80's Argo where the previous owner put bolts instead of pins on every sprocket, and can tell you all for a FACT that if you run bolts you will elongate your sprockets a lot more than if you use Spirol coil spring pins. In addition, you're going to eventually bust something. This rig had a broken idler shaft.

Here's why I'm not a fan of putting in bolts. A 5/16 grade 5 bolt has a tensile strength of 120,000 psi. Shear isn't published as an ASM standard for bolts, but the recommended calculation for shear is 60% of tensile. That gives you a shear strength of a grade 5 bolt of 72,000 psi, roughly nine times the shear of a similar coil spring pin!

Kind of gets you thinking it may pay to stick with pins.

Thanks guys...

Bob

[Planter Bob]

I was hoping someone would help out here, but no worries...I'm still researching on my own.

I went ahead and ordered 25 pins from Grainger (Item #5EB84). Total cost, including USPS Priority Shipping to Alaska, was $30.03. That works out to around $1.20 a pin, a savings of about $25 over what Argo wants for the same quantity.

I'm replacing every pin on my rig with these new pins, and will let you guys know how they work out. I'm HOPING they will shear properly. At 8,700 psi, they should. I'll be real concerned if I stop breaking pins using these. It's worth $30 for the experiment.

[Jeff t-boss]

PB..; The roll pins are in the drivetrain system for the simple reason to creat the weak link in the drive train. I'm sure you are aware of that. I've read alot aboput people switching over to solid bolt only to have more severe/expensive problems down the road. I'd much rather change a 50 cent roll pin 3 or 4 times and adjust my driving/beating habits than bypass the purpose and have more drastic and expensive breakdowns in the future. The roll pins are the waek link in the chain and I treat them as just that simply because that's the way it way designed.

[Planter Bob]

Agreed 100%...and that's why I'm trying to get the proper ones!

The guy I got my parts machine from put bolts in instead of pins, and wondered why he busted an idler shaft. It probably didn't help he had chains on the front wheels, too! I know...he was just ASKING for it! His loss, my gain. I got the whole rig, with running motor and working tranny, for only $400.

I'm happy to break pins. That's the goal, after all. My big concern is putting in the wrong pin, one that has too high of a shear strength.

Here's a dirty little secret; Argo doesn't know ANYTHING about the pin their parts manual says is used in my machine! Yup...if you look in the latest/last parts manual for my rig, it lists two part numbers for the pin, depending on serial number. The older rigs take 111-05, and the newer models take 11145, with no tell-tale Argo dash in the number. If you talk to any Argo dealer, they cannot find this dash-less part number in any of their inventory listings from Argo.

I'd almost like to work backwards from Spirol, but my guess is they'd be slow to share trade details with me regarding what they supply Argo.

Planter Bob

[evil8x8]

I just use tension pins from the local hardware store in my Argo 8x8. The first year or two that I had my Argo I would break them all the time but now I can drive it without breaking any. If you take it easy and keep steady throttle and brake over rocks, logs, and other obstacle where only a few tires are on the ground at a time, you will brake less pins. I made it the whole 2009 Ledges without breaking a pin.

[Newfy Moose]

Spirol spec sheet

Hi Planter Bob,

Just checked out the spirol spec sheet. The 8700 lbs shear force is rated as a standard pin. Their heavy duty pin is rated at 12000 pounds. I have some elongated holes in my front axles. I am thing I will try and replace them with standard 3/8 pins which have a rating of 9600 lbs, if I can get them.

http://www.spirol.com/library/main_catalogs/cldp_us.pdf