thru-bolting the underside of the overhang

[doghouse_riley]

I'd like to install a pair of z-bars under the overhang to store a folding table or possibly a portable solar panel. I've seen some photos/threads on this, but I'm hoping to get some details or precautions on securing the bars to the camper. Would I thru-bolt with carriage bolts? Would they need to be counter-sunk to avoid interfering with the sliding bed? Do I need to be concerned about framing members? any other precautions/suggestions?

Thanks!

 

[CougarCouple]

Can’t speak to all pop up campers.
But I would use a “C” channel with sex bolts and definitely spread the load with a strip is sheet metal on the inside. I think the under side of sleeping platform is jus plywood on 4wc ad ATC.
Be careful of eliminating the clearance between truck cab ad camper.

Russ

 

[JaSAn]

I use T-nuts:
https://www.mcmaster.com/tee-nuts

 

[camper rich]

I use T-nuts:
https://www.mcmaster.com/tee-nuts

X2 I also use T-nuts. We bought our 2016 Grandby from Paul at Equipt Expeditions in Salt Lake City. He is also the importer for
Eezi Awn products. We had him install a really nice Eezi Awn Stainless Steel Table under the overhang that sits on some padded Z rails and has a lock that swings down to keep it from being stolen. On the other side of the camper from the table, I built a 3-1/2" box that holds my 8' ExtendnClimb Ladder that I use to tie my Kayaks on with. I did have to build a frame of 2 x 3s to go in the truck bed to give me the clearance I need to keep the box from hitting the cab, but it all works well for what I do, which is Baja Trips.

 

[Vic Harder]

Agreed on the T-nuts. The material is NOT very strong though, I think it relies on being a laminate for strength. I bought 1/4" T-nuts and a length of 1/4" threaded rod. The T-nuts sit almost flush on the bed surface. Use thread locker to keep them from turning loose from vibration.

P.S. Had to laugh at Russ' "sex bolts" in the bed area...

 

[BFH4N]

T-nuts would be fine, but I think flat-head screws would be just as good. Maybe acorn nuts on the outside. All stainless steel, of course. I wouldn't hang anything real heavy this way.

 

[Zirdu]

That 3M VHB tape can be incredibly strong. I think you could use that on some L brackets to simply attach to the bottom of the overhang. Preparing the surfaces in accord with all directions for use of VHB tape. Then maybe add two or three simple screws to help tack it all down. So long as you did not put too much weight on it, I think it would hold.

 

[ramblinChet]

X2 I also use T-nuts. We bought our 2016 Grandby from Paul at Equipt Expeditions in Salt Lake City. He is also the importer for
Eezi Awn products. We had him install a really nice Eezi Awn Stainless Steel Table under the overhang that sits on some padded Z rails and has a lock that swings down to keep it from being stolen. On the other side of the camper from the table, I built a 3-1/2" box that holds my 8' ExtendnClimb Ladder that I use to tie my Kayaks on with. I did have to build a frame of 2 x 3s to go in the truck bed to give me the clearance I need to keep the box from hitting the cab, but it all works well for what I do, which is Baja Trips.

If you have pictures detailing your installation I would love to see them since I am interested in doing the same.

Paul is a great guy - I purchased my National Luna 80L refrigerator from him years ago and met him at Overland Expo East in 2019.

 

[doghouse_riley]

thanks all for the replies!

 

[BrianG]

I just used 1/4” stainless lag bolts with lock washer, not one has come loose in 5 years. I carry a 2x4’ table there. I’ll try to attach a picture. The plywood is 5/8” so keep your lags short. I wouldn’t want to drill holes through that area, it’s not necessary.
[sharedmedia=core:attachments:23993]

 

[BrianG]

Here is a better photo of my under bed table holder. Washer plus lock washer. I also use UHMW tape on top and bottom to prevent scraping on wood and for easy sliding on L bracket. Got the 1/4” brackets from Online Metals. Good luck.

 

[ramblinChet]

Great photos and thank you for the tip on UHMW tape - I spent time learning about it and it is quite interesting when it comes to being slippery and reducing noise.

 

[CougarCouple]

Was not thinking of that Vic, but now That you mentioned it[emoji41][emoji41][emoji41]

https://en.m.wikipedia.org/wiki/Sex_bolt

Using the correct ones produce awesome fasteners especially for this project.
“T” nuts work I guess as others have said.
I would want a backing plate to spread the load. Even a thin continuous strap on each side. JMO.

Russ

 

[ntsqd]

T-nuts or sex bolts both create a sandwich of the plywood rather than relying on the tear-out strength of threading into the plywood. I don't particularly care for lag bolts, so one of the former would get my vote. Along with some 5200 or Hylomar or The Right Stuff (depending on what was close to hand) to keep moisture from working in thru the holes.

 

[BrianG]

One note about lag bolts, stainless lags have deep and sharp threads. Make sure your t-nuts are stainless. As a cabinet maker in a previous life t-nuts creat large holes that are not easily reparable later and they will leave a slight space between the two pieces. But both will work. Added note/ correction, I looked at my collection of t-nuts and some do fit flush.