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JackIIA
03-31-2010, 03:41 PM
Granted, being abit overly analytical here, but wanted some thoughts on this.

I've bought some cad plated bolts, washers, nuts for my refurbishment. I know from aircraft mechanics that split washers are a waste of time for anti-loosening purposes and cad-plated nyloc isn't always available in the sizes I sought.

So, do folks just apply some loctite to the bolt threads and then just add a nut to hold everything in place? Any reason why this isn't a reasonable solution? It sure would be alot easier.

While I'm not talking about suspension bolts, I am thinking of many other parts of the truck, some of which could be considered semi-critical. And FYI, I would assume blue loctite would be enough??

Thanks.

amcordo
03-31-2010, 03:49 PM
I just removed a million bolts from my rig that had split washers holding them in. Ignoring the ones that were just rust-locked, the split washers seemed to do a great job of keeping things together. And it's been at least fifteen years since they were installed.

Just thought I'd mention that - even if something doesn't work in another application doesn't mean it's not strong enough for ours. :)





Granted, being abit overly analytical here, but wanted some thoughts on this.

I've bought some cad plated bolts, washers, nuts for my refurbishment. I know from aircraft mechanics that split washers are a waste of time for anti-loosening purposes and cad-plated nyloc isn't always available in the sizes I sought.

So, do folks just apply some loctite to the bolt threads and then just add a nut to hold everything in place? Any reason why this isn't a reasonable solution? It sure would be alot easier.

While I'm not talking about suspension bolts, I am thinking of many other parts of the truck, some of which could be considered semi-critical. And FYI, I would assume blue loctite would be enough??

Thanks.

SafeAirOne
03-31-2010, 04:08 PM
Many aviation requirements specify some sort of positive locking method for fasteners ( castellated nuts with cotter pins, safety wire, etc.) or nyloc nuts. This is not necessarily because things are always falling off, but rather that just one loose 1/4" nut, let's say, can bring an aircraft down if it is rattling around in the wrong place.

Not really so critical on a 35 year old Land Rover. Use NEW lockwashers every time and you'll be all set.

Oh, and if you insist on the LocTite route, I'd use blue. The red will be a bit of overkill on most fasteners.

greenmeanie
03-31-2010, 04:32 PM
Is there a reason you feel you need CAD plated nuts everywhere other than colour co-ordination? Zinc plated ones will last just fine. The benefit of the nyloc is that you can have a locking feature plus antisieze making it easy to remove in the future.

Belleville washers work well inplace of the crappy split ones. Split washers are an adequate solution for a Rover, just not the best. They are better than common blue loctite and no mechanical device.

CAD plated fasteners are getting more difficult to find because a lot of the big companies no longer use them due to the toxic nature of the plating process for cadmium. Finding a NADCAP rated shop that will do it costs lots of money and just is not worth it given the alternatives.

gudjeon
03-31-2010, 06:00 PM
Under the nut, I use a spring washer and flat washer. I have never had anything work loose with this combo. I use copper never-sieze on stuff I may need to get at after some time. For the body, I don't mind a cheaper hardware store variety as I can just break them off when it needs to be stripped down after another 50 years.:thumb-up:

JackIIA
03-31-2010, 06:09 PM
Is there a reason you feel you need CAD plated nuts everywhere other than colour co-ordination? Zinc plated ones will last just fine. The benefit of the nyloc is that you can have a locking feature plus antisieze making it easy to remove in the future.

Yeah, unbelievable frustration with removing seized bolts using muscle, heat, hacksaws, and a hammer to destroy my truck (after throwing it across the room afew times). So, my approach is admittedly one of intentional overkill! I like the nyloc, I just don't always see it as available in CAD. I won't be using CAD everywhere, but when I can get it and it's not too expensive, I'd like to.




Belleville washers work well in place of the crappy split ones.

This I had not thought of. I don't know all my fasteners. Not a bad idea.


They are better than common blue loctite and no mechanical device.

OK, that's what I was worried about. McMaster Carr said "no problem" to use locktite alone. Guess that might not be true.


CAD plated fasteners are getting more difficult to find because a lot of the big companies no longer use them due to the toxic nature of the plating process for cadmium.

Yes, but I have seen some relatively cheap sources online. Takes some digging though, admittedly. McMaster Carr is NOT one of them, though they are a great resource.

JackIIA
03-31-2010, 06:12 PM
And I believe CAD is effectively innert (sp?) with just about everything. So I can mix some cheapo belleville washers with them from HD??

Incidentially, found a site online where a guy was doing this in his garage. GREAT results. Though no way would I try it. In addition to some calculations beyond my science threshold, just way to toxic...and probably illegal.

I like my lungs the way they are...

http://forum.ih8mud.com/40-55-series-tech/307072-yellow-zinc-cad-plating.html

jac04
04-01-2010, 07:04 AM
OK, that's what I was worried about. McMaster Carr said "no problem" to use locktite alone. Guess that might not be true.
The blue Loctite, when applied properly, will work much better than split lock washers in an application subject to significant vibration. It also acts as a threads lubricant, allowing you to obtain the same bolt preload with a lower bolt torque. Remember, proper Loctite application usually involves cleaning both the internal & external threads before applying, something most people don't do.

Wander
04-01-2010, 08:03 AM
If you're doing a lot of wrenching the nyloc's will add to your wrenching time which can be frustrating. I'd suggest the blue loc-tite over red or green as those often require heat, breaker bar, C-4, divine assistance, etc. to remove.

JackIIA
04-01-2010, 06:06 PM
Gents, thanks. And Jeff, I am one of those people who forget to hit the threads with lacquer thinner. Doh!!!!