The correct Elevator bolt size is?

[Lance M]

I went to Fastenal after searching the forums to get the correct elevator bolts on order (1/4-20). When she showed me the picture, I knew that they were not exactly the same as what was originally used. Here are pictures of the original

As you can see the head of the bolt is 9/16". The CAD drawing listed the head diameter as .969"-1.008".

Here's what McMaster-Carr has with a 31/32" head.
McMaster-Carr

Fastenal has this
1/4-20X2 ELEVATOR BOLTS, 18-8SS | Fastenal

Vintage trailer supply has one that looks just like the Fastenal
Floor Repair Bolts

Anyone know where to get the 9/16" head bolts? I know that I need to use a forstner bit to sink them in.

If not, is the larger diameter head better than the original? Thanks!

[Lance M]

Anyone?

[markdoane]

I would use elevator bolts. Vintage Trailer has a good price.

The original bolts with the 9/16 head - don't know what those are called but they don't look like elevator bolts.

[Beaker63]

lance,
I used the bolts from VTS, they were the same head diameter as the orginals. I think I bought a bag of fifty. Ran short and found that my local hardware store carried them in bulk. They were black not plated. I think a larger head would be fine, maybe better as long as they lay flat on the floor.
Tim

[BradS]

A larger head will give you better hold. I dont know that the small difference will matter all that much

[Wabbiteer]

I came across a pile of them that were worn out - did'ya know the elevator part means a conveyor belt feeding a grain elevator? I've seen a couple of different flavors of them, embossed rings on the face, bright galvanized,etc. but the smooth faced black oxide coated may be the best steel, its not fun when your conveyor belt comes apart and that's the type I found with the heads dished out from abrasion of wheat at our local grain elevator.

[InsideOut]

We used the elevator bolts that VTS has in replacing the floor in our '56 Safari.



Shari

[Lance M]

Originally Posted by Wabbiteer

I came across a pile of them that were worn out - did'ya know the elevator part means a conveyor belt feeding a grain elevator? I've seen a couple of different flavors of them, embossed rings on the face, bright galvanized,etc. but the smooth faced black oxide coated may be the best steel, its not fun when your conveyor belt comes apart and that's the type I found with the heads dished out from abrasion of wheat at our local grain elevator.

Thanks Wabbiteer. Having grown up on an Iowa corn farm, it's not the first time I've heard mention of this type of fastener. I guess that's why they are next to the plow bolts at Fastenal.

I plan to stain the plywood floor with a rusty orange color and then finish with West Marine epoxy coating. I'm only truly concerned with the few of these that will be exposed. I might go with countersunk carriage bolts for the areas that will be exposed. I think that a 1" diameter head will not be aesthetically pleasing.

[Colin H]

Hi Lance & all,
The elevator bolts that VTS sells have slightly larger heads than originally installed in Airstream's, however I think this a good thing. As there is a larger surface area, they will hold the plywood down better if installed as Airstream did originally along the joints. I typically offset the bolts so the complete head is next to the joint instead of straddling the two pieces. The 1 1/2" version can be used for most applications however the 2" versions are needed on some 70's era trailers that have recessed crossmembers along with a plywood "mending plate" along the joints. Although Airstream used wood screws around the perimeter of the trailer, inside the walls, between the outriggers, I prefer to use elevator bolts as this assures a long term connection between the base of the wall & floor. I use 1/4-20 hex bolts & washers to fasten the base of the wall, floor & outriggers together.
Good luck with your repairs,
Colin

[Lance M]

Thanks Colin! I guess that's why you're on the VAP as a Pro

[Lance M]

Just for everyone's wonder and amazement at how much fun it is to look at a Fastenal catalog, I found the correct nomenclature of the original bolts holding the floor down.
"Weld Screws" they are called. Fastenal has them listed in their catalog on page 3-128. Now I know and you do too.

[bwoodtx]

I think that given the info in the online catalogue, I would go with the elevator bolt vs the weld screw simply because of the square shank which resists turning. jmho i have no experience with this----YET. that is in my future.

[Lance M]

Bruce et al.,
I'm going with all stainless steel hardware. Weld screws do not come in stainless. I'm using hex head bolts for inside the C channel, flat head screws for the parts of the floor that will be exposed and elevator bolts for the areas that are to be covered up. All places where dissimilar metals join will be separated with nylon washers and coated with epoxy polymide primer and bolted up while still wet. I'm replacing the large steel plates inside the C channel with 2x thicker aluminum plate. That should hold it for at least another 40 years.

[tvanwave]

Why cant plain old carraige bolts be used? Im redoing the back of a 1991 34' and the nuts are in the c-chanel and heads inside belly pan, wraps, and otherwise out of sight.

[Lance M]

Originally Posted by tvanwave

Why cant plain old carraige bolts be used? Im redoing the back of a 1991 34' and the nuts are in the c-chanel and heads inside belly pan, wraps, and otherwise out of sight.

Tvan,
I think you can sure use carriage bolts in the C channel. I'm just going with the hex bolts in the C channel because they come in stainless and Fastenal stocks them on the shelf.

[Colin H]

You could use carriage bolts, however I use regular hex bolts with washers on both sides inside the "C" channels. I use elevator bolts through the floor where floor covering will be put on top.
Colin

[Canlib]

Look!! stainless elevator bolts! Elevator bolts at Bolt Depot
Just found this tonight.

BTW I found no need to drill the elevator bolts into my spruce ply flor. About 10 % spun, but I could grip the bolt below the nut with vice grips and continue tightening until the head pulled belw the flor surface.

[perryg114]

I know this is an old thread but on my 81 the elevator bolts were screwed in from the top and the frame members were threaded. So you have to have some sort of head to be able to drive the screw down. I was able to find slot head elevator bolts from Mcmaster.com but the slotted heads were a pain to drive in without the bit slipping off. The phillips head bolts that AS used would have been better.

McMaster-Carr

Perry