rethinking things... subfloor install

[ROBERT CROSS]

Originally Posted by skyguyscott

Thanks for brushing us up, Bob; I was getting a little rusty.

No problem...BUT, you did notice that 'rust' is not on the list and as such is not a form of 'corrosion'.

Bob
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[mikextr]

Originally Posted by zen_stream

All really good input here everyone!

On a side note, I really like the idea of "fanged" elevator bolts! Im assuming they have a couple teeth sticking down from the bottom of the flange? That would work well for me because I'm using coosa composite for a subfloor and my current elevator bolts often have a hard time gripping without wood. Most go in fine but some strip themselves out and need to be held from above. Makes a one person job into a 2 person job. That's the kind of stuff that keeps me behind on this build haha.

Yes. Fanged elevator bolts would be nice. Had the same problem with a few of the elevator bolts on my wood floor. I didn't want to wait for a helper so I injected quick setting epoxy under the top of the bolt and worked on other stuff while the epoxy cured. After the epoxy set, the bond was strong enough for me to torque the nuts down pretty tight.

[mrdes8]

Yep... spinning elevator bolts, run a regular nut up and then double-nut with a nylock (good to have some kind of nut-driver) or, if you're working on an Airstream, chances are you have a 1/8 drill chucked up, drill a hole in the elevator bolt head edge and then insert implement of choice to hold it, seems I have a selection of several picks so I can do several at a time...
Keep it going, Mark D

[guskmg]

I am wondering what percentage of elevator bolts work themselves loose over time. Maybe the looseness is caused by the floor material drinking?
how about it?
guskmg

[zen_stream]

All right so here's another stupid thing I'm losing sleep over. I've been breaking a few of these elevator bolts when trying to pull them flush. Should I be worried that I'm overnighting them at this point? Will they just pop once I hit a pothole?

[John57]

Be careful when mixing alloyed metals. For example stainless fasteners to attached to aluminum, electrolysis take place and will cause aluminum corrosion. That’s the reason AS used black iron bolts to attach the sub floor. Stainless steel bolts have a higher tensile strength but also have tendency crack and break cause by continuous vibration. All fasteners are good but use in the right application.If you put dielectric lubricate on SS bolts threading into aluminum it will stop the corrosion. Just my two cents.

[steinVT]

My last build I used SS Neoprene Bonded Sealing Washers, SS bolts and SS nylon locking nuts. The idea being the neoprene contacts the aluminum instead of the SS. Seemed to work really well.

[kevinkatz]

Originally Posted by zen_stream

All right so here's another stupid thing I'm losing sleep over. I've been breaking a few of these elevator bolts when trying to pull them flush. Should I be worried that I'm overnighting them at this point? Will they just pop once I hit a pothole?

I just put a whole lot of new ones in and broke some. Assume that they can’t be tightened too much.

[zen_stream]

Well I didn't do a neoprene washer underneath them. I was just going to por15 the bolts so they don't get water intruding. Can that type of corrosion between SS and ALU happen without water present?

[steinVT]

If you can keep the water out, I don't think there will be a galvanic reaction. But that is a big if. In 50+ year old trailers I have worked on, most of the C channel was good and only some was completely rotted away. Using the POR15, you'll be fine. - Mark

[Voltair]

As dissimilar metals are the cause off these concerns I have a chart somewhere that lists from Anode to cathode their properties so you tend to choose from the list any two that lay close together. So i'd use a 1/4" aluminium soft washer under the head off a marine stainless bolt with a soft Red Locktight thread sealer as it will keep on hardening over time and also prevent the stainless bolt and nut from gaulling, some cheap stainless bolts sold on the market do shear easy and lockup, so buy American Made or Euro made n pay up the extra $1 otherwise good luck you'r more than likely going to need it ! Mild steel black bolts up against alli ummmm I dont think so!!

[ROBERT CROSS]

Originally Posted by John57

Be careful when mixing alloyed metals. For example stainless fasteners to attached to aluminum, electrolysis take place and will cause aluminum corrosion. That’s the reason AS used black iron bolts to attach the sub floor. Stainless steel bolts have a higher tensile strength but also have tendency crack and break cause by continuous vibration. All fasteners are good but use in the right application.If you put dielectric lubricate on SS bolts threading into aluminum it will stop the corrosion. Just my two cents.

YEP>>>


Been doing it for years....SFSG

Bob
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