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(3) or (4) Bolts...
Posted: Sun Dec 03, 2017 8:09 pm
by pdq67
Where can I buy (3) or (4), 3/8" dia. x 2-3/4" long UNF hex-head bolts in 300M quality??
I broke an ACE Hardware Grade-8 bolt that I was using to hold my mulch mower's, 21", "Gater", blade on with this morning so I want a stronger bolt!
Or somebody please tell me a better than Grade-8 bolt besides 300M quality to use in my application...
Thanks,
pdq67
PS., and I know that I am not supposed to be mulching 1" dia. sticks using my old commercial steel deck, green, Lawn-Boy mulch mower, but I do..
I installed a 5hp B&S engine on it and running about 1/2 throttle, boy does it mulch stuff up!!!
Re: (3) or (4) Bolts...
Posted: Sun Dec 03, 2017 9:26 pm
by 1989TransAm
How about AN bolts that I believe are stronger than grade 8. I use them in certain applications. They in increments of 1/16" thickness. So an AN6 would be 3/8". An AN4 would be a 1/4", an AN8 would be 1/2" and so on.
Here is a link to one source.
http://www.aircraftspruce.com/catalog/s ... nbolts.php
Re: (3) or (4) Bolts...
Posted: Sun Dec 03, 2017 10:12 pm
by Keith Morganstein
pdq67 wrote: ↑Sun Dec 03, 2017 8:09 pm
Where can I buy (3) or (4), 3/8" dia. x 2-3/4" long UNF hex-head bolts in 300M quality??
I broke an ACE Hardware Grade-8 bolt that I was using to hold my mulch mower's, 21", "Gater", blade on with this morning so I want a stronger bolt!
Or somebody please tell me a better than Grade-8 bolt besides 300M quality to use in my application...
Thanks,
pdq67
PS., and I know that I am not supposed to be mulching 1" dia. sticks using my old commercial steel deck, green, Lawn-Boy mulch mower, but I do..
I installed a 5hp B&S engine on it and running about 1/2 throttle, boy does it mulch stuff up!!!
Caterpillar dealer nearby? The CAT bolts, grade 8 or 9 (some sizes are grade 9) are much better than what you buy at the hardware store. The price is good too.
Sometimes a higher grade bolt isn't better. On a brand of excavator I worked on, the track frames were bolted on with 1 1/2" dia bolts. Grade 8 bolts broke, but Grade 5 held up.
Re: (3) or (4) Bolts...
Posted: Sun Dec 03, 2017 10:30 pm
by dave brode
Re: (3) or (4) Bolts...
Posted: Tue Dec 05, 2017 1:52 pm
by pdq67
How about if I have a local Machine Shop turn down (1) SBC 300M head bolt, shorten it to 2-3/4" long and then put a 3/8" UNF thread on it??
Would it hold up or would there be too many stress risers on it??
I figure the head bolt will have rolled threads is why I ask..
pdq67
Re: (3) or (4) Bolts...
Posted: Tue Dec 05, 2017 5:53 pm
by Dave Koehler
Don't make this so complicated.
Go to CAT as suggested and get a bolt.
The only reason that the original broke is
1: You hit one hell of a rock and there is likely other damage.
or
2: The bolt has been over torqued repeatedly with an over enthusiastic impact.
Re: (3) or (4) Bolts...
Posted: Tue Dec 05, 2017 8:25 pm
by pdq67
Thanks Dave.
pdq67
Re: (3) or (4) Bolts...
Posted: Wed Dec 06, 2017 5:06 pm
by Keith Morganstein
CAT part number 0L-0139
3/8"-24, 2-3/4" bolt length, 1.75" grip length,
9/16" hex head, phosphate and oil coated.
Prob around $2.00 a bolt.
Pick it up at a CAT dealer, authorized CAT truck or marine service shop, have one of these ship them to you or from cat parts online.
Re: (3) or (4) Bolts...
Posted: Thu Dec 07, 2017 7:28 am
by Keith Morganstein
Keith Morganstein wrote: ↑Wed Dec 06, 2017 5:06 pm
CAT part number 0L-0139
3/8"-24, 2-3/4" bolt length, 1.75" grip length,
9/16" hex head, phosphate and oil coated.
0L-0139. List price $.81 ea
Re: (3) or (4) Bolts...
Posted: Tue Dec 12, 2017 6:07 am
by pdq67
I went out to our local Cat. Dealer and they didn't have any in stock like I want.
Would have to come out of St. Louis so I will just stop for now. I probably won't need my mulch mower until next spring.
Later,
pdq67
Re: (3) or (4) Bolts...
Posted: Tue Dec 12, 2017 9:07 am
by Dave Koehler
MCMaster Carr 91257A662 pak of 10 $8.30
you know,...that may be the longest blade bolt I have run across.
Re: (3) or (4) Bolts...
Posted: Tue Dec 12, 2017 11:21 am
by pdq67
I have to admit that I MISS-TYPED, it's 1.75" long, not 2.75" long.
My bad.
pdq67
Re: (3) or (4) Bolts...
Posted: Tue Dec 12, 2017 10:39 pm
by MadBill
Some times what you need is a tougher bolt, not a stronger one...
Re: (3) or (4) Bolts...
Posted: Tue Dec 12, 2017 10:55 pm
by pdq67
Bill,
That is why I wanted 300M grade bolts because it is tougher than, "railroad spikes", imho!
pdq67
Re: (3) or (4) Bolts...
Posted: Wed Dec 13, 2017 1:20 pm
by tjz450
I suggest unbrako Allen head with harden washer. Without double checking specs AN bolts aren't better than grade 8,( G8's are too brittle). iirc.