Catalina 34

General Activities => Main Message Board => Topic started by: DaveBMusik on February 20, 2017, 06:45:09 PM

Title: chainplate bolts
Post by: DaveBMusik on February 20, 2017, 06:45:09 PM
I am in the process of re-bedding my chainplates and looking to order replacement hardware from McMaster-Carr. It looks like the slotted round head bolts are only available in 18-8 stainless and not 316.
Is 18-8 sufficient or does anyone else have a better source?

Thanks!

- Dave
Title: Re: chainplate bolts
Post by: KWKloeber on February 20, 2017, 06:58:11 PM
Uuuuuuuuuuuh. What size?
Title: Re: chainplate bolts
Post by: DaveBMusik on February 20, 2017, 07:54:41 PM
I believe they are 3/8 x 1 3/4
Title: Re: chainplate bolts
Post by: KWKloeber on February 20, 2017, 08:35:03 PM
Fastenal carries 316 ss 3/8-16 machine screws.
Probably also Grainger, BoltDepot, etc.

ken

Quote from: DaveBMusik on February 20, 2017, 07:54:41 PM
I believe they are 3/8 x 1 3/4
Title: Re: chainplate bolts
Post by: DaveBMusik on February 21, 2017, 06:36:57 AM
Quote from: KWKloeber on February 20, 2017, 08:35:03 PM
Fastenal carries 316 ss 3/8-16 machine screws.
Probably also Grainger, BoltDepot, etc.

ken

Quote from: DaveBMusik on February 20, 2017, 07:54:41 PM
I believe they are 3/8 x 1 3/4

They all have 1 1/2 & 2 but nobody seems to have 1 3/4 in 316.

Is it true that 18-8 (304) is stronger than 316?

I do remember reading that someone had replaced theirs with hex heads instead of the original slotted round head. I would prefer to stick with the round head unless the prevailing wisdom is that 316 is more important.

Title: Re: chainplate bolts
Post by: KWKloeber on February 21, 2017, 10:22:13 PM
Soooooooo jus cuttem off?  Everyone needs a 15$ HF angle grinder and stainless cut off discs!
Title: Re: chainplate bolts
Post by: Jon W on February 21, 2017, 11:01:58 PM
18-8 sst has comparable strength characteristics as both 316 and 316L. However the 18-8 corrosion resistance is not as good as 316 or 316L.

As an FYI 18-8 is a generic material. Sometimes called 304 or 302 (old), but isn't unless it has the 5% nickel in it. If you want 304 or 304L, specify 304 or 304L.

When I can't get the right length for small fasteners like this, I install the fastener then thread on a nut and tighten. Then clamp the 2nd thread sticking beyond the nut with a pair of vice grips. Wiggle back and forth and the fastener will break leaving a clean edge where you gripped it with the vice grips. Remove the nut and replace with an acorn nut or whatever finishing nut you plan to use.
Title: Re: chainplate bolts
Post by: Jim Hardesty on February 22, 2017, 04:35:06 AM
QuoteSoooooooo jus cuttem off?  Everyone needs a 15$ HF angle grinder and stainless cut off discs!

I couldn't agree with Ken more.  But.  For people not used to power tools, and for the little jobs my choice is a Dremel.  Great little tools. 
Jim
Title: Re: chainplate bolts
Post by: KWKloeber on February 22, 2017, 07:29:10 AM
Breaking off the last 1/4" of a 3/8" machine screw --- you've got a stronger grip and heftier locking pliers than I have!

If you don't want to trim it, I'd suggest a recessed hex drive -- easier to hold than a slotted head and better than a Phillips head because it's not designed to strip out like a Phillips head is.  I've used flathead hex a few places on the boat. 

McMaster 3/8" x 1-3/4 in passivated 316.  Can't get better than that.  well not easily anyway.

(https://images1.mcmaster.com/mvB/contents/gfx/large/98164ap1-b01l.png?ver=1382525599)
Title: Re: chainplate bolts
Post by: DaveBMusik on February 22, 2017, 07:51:34 AM
Quote from: KWKloeber on February 22, 2017, 07:29:10 AM
Breaking off the last 1/4" of a 3/8" machine screw --- you've got a stronger grip and heftier locking pliers than I have!

If you don't want to trim it, I'd suggest a recessed hex drive -- easier to hold than a slotted head and better than a Phillips head because it's not designed to strip out like a Phillips head is.  I've used flathead hex a few places on the boat. 

McMaster 3/8" x 1-3/4 in passivated 316.  Can't get better than that.  well not easily anyway.

(https://images1.mcmaster.com/mvB/contents/gfx/large/98164ap1-b01l.png?ver=1382525599)

Thanks Ken!

I would not be too interested in cutting 12 3/8' bolts.

So, these look good and the advice is to stick with 316.

Thanks!
Title: Re: chainplate bolts
Post by: Jon W on February 22, 2017, 10:05:48 AM
You should give it a try, you'll be surprised how easy 1/4" is. No mess and no heat introduced into the fastener.
Title: Re: chainplate bolts
Post by: KWKloeber on February 22, 2017, 10:20:37 AM
Quote from: Jon W on February 22, 2017, 10:05:48 AM
You should give it a try, you'll be surprised how easy 1/4" is. No mess and no heat introduced into the fastener.

Yeah! I've done it MANY times with #8, #10, 1/4" 
But not 3/8" with only a 1/4" sticking out and 1/4" to remove.  No leverage to get any work hardening to get going. 
a 3/8 bolt is pretty hefty -- more then twice the material compared to 1/4"
Title: Re: chainplate bolts
Post by: Noah on February 22, 2017, 10:58:13 AM
Jon just removed and rebed his chainplates. I would take his advice.
Title: Re: chainplate bolts
Post by: KWKloeber on February 22, 2017, 11:46:21 AM
Jon,

is that what you did?  You snapped 1/4 inch off the end of the 3/8" bolts that you used?

kk
Title: Re: chainplate bolts
Post by: Jon W on February 22, 2017, 09:07:06 PM
Closer to 1/2".

Did the same on the 1/4" fasteners around the mast collar and the new clutches I added to the cabin top.
Title: Re: chainplate bolts
Post by: KWKloeber on February 22, 2017, 09:20:18 PM
Yep That I can buy into.  1/4 for the vice grip, 1/4 for the work hardening bend.
The last time I did that it was 5/16" installing clutches. I threaded a die onto the machine screw instead of a nut, snapped and retreaded the burr backing it off.  They were buried so didn't need to finish them w/ an acorns.
Title: Re: chainplate bolts
Post by: Noah on February 22, 2017, 09:20:42 PM
Nice Jon! I knew you weren't just blowing smoke tough guy! :clap
Title: Re: chainplate bolts
Post by: Jon W on February 22, 2017, 09:39:55 PM
Just trying to help. Now back to my propane locker project.
Title: Re: chainplate bolts
Post by: KWKloeber on February 23, 2017, 07:41:18 PM
If anyone's interested that 15$ HF angle grinder is now (drum roll) 10$ on Fri, Sat, Sun w/ coupon....

kk
Title: Re: chainplate bolts
Post by: lazybone on February 24, 2017, 06:12:04 AM
Quote from: KWKloeber on February 23, 2017, 07:41:18 PM
If anyone's interested that 15$ HF angle grinder is now (drum roll) 10$ on Fri, Sat, Sun w/ coupon....

kk

You can't have too many angle grinders.  It's nice to have them set up with different cutting, grinding and wire wheels.
I don't understand the dremil fascination.
Title: Re: chainplate bolts
Post by: Phil Spicer on February 24, 2017, 05:19:37 PM
   Dremel...small, compact, fits in small places, but it is light duty. It has it's place.
Title: Re: chainplate bolts
Post by: KWKloeber on February 25, 2017, 07:32:12 PM
Quote from: Phil Spicer on February 24, 2017, 05:19:37 PM
   Dremel...small, compact, fits in small places, but it is light duty. It has it's place.

Not to mention (but I will) that although their speeds are in the same ballpark, a 4" wire wheel or sliver stainless cutting blade can tear up an arm pretty quick.  For the inexperienced, slower and steadier may be better than the ease of cutting with an angle grinder.  Quantity also plays into it.  If i'm trimming off one 1/4" in the saloon, I'd grab my "rotary tool" (a Skill brand.)  But if I'm doing a dozen, then the angle grinder.  Same for cleaning up threads -- one -- a rotary tool,  but a dozen -- an angle grinder clamped onto a plank or my stepladder.

kk