Stop bickering, you're both wrong. No scab plates would mean only the end of a tube is attached to the frame, and the contact area would be approximately Pi*d*thickness of the tube. But I got the information I needed, so thanks everyone.

 

we're talking about loaded SA frame side. in which case we're right.
the plates would stil cover more area and "weld length" no matter because youd obviously make your plate bigger than your tube dia.

 

welding is better

 

I have some input from the bolt-on side of things. I have RB sliders bolted on. My sliders have been well used/abused and I'm beginning to see adverse affects of the way they are bolted on. They were bolted on by drilling mounting holes in the frame and using 4 thread forming bolts per mounting leg (8 bolts per slider).

In my opinion, the frame is just not thick enough to provide enough bearing surface for the threads of the bolts. This is evidenced by the fact that I have had 2 of the bolts tear out of the frame. Also, the force exerted on the sliders is focussed to too small of an area of the frame. This is evidenced by the fact that my frame is pulling where the bolts mount. It is actually bulged out where the sliders mount. Fortunately the way Roger's sliders are designed the force isn't all tension on the bolts so they haven't just ripped off of the truck.

Personally I think the best way to mount the sliders would to weld sleeves in the frame for through bolts with a backing plate on the back side of the frame that matches the plate on the sliders. This would distribute the force the best and allows the sliders to be removeable. This is also overkill for most people and a ton of work.

 

make a |_| shaped bracket which 'wraps' the frame rail, and bolt it all the way through the frame. that's what i plan on doing.

 

This is definately much better. But without the sleeves it could end up looking like /_\. Also, if the bracket is not completely snug you could get some rattling, especially when you come down on them.

Not to say that this is a bad method. I know it's been used very successfully. No matter how you mount sliders I think you can expect some frame deformation if you abuse them enough.

 

i'm gonna use 1/4" plate....if it ends up looking like /_\ i think i will have bigger problems to worry about

getting them snug is the one thing that will take some time/patience.

 

I had mine welded on my 95, ground them off and going on my 92....MUCH stronger...use a backing plate..and call it a day.

 

these are our bolt on mounts, they utilize the u shaped bracket, with bolts over the top of the frame and sleeves to prevent over tightening, the mounts are also predrilled for 3 self tapping bolts, 2 for the face of the frame and 1 for the bottom of the frame, this is in our opinion the best way we have found to bolt a set of sliders on.
if you weld them on be carefull what kind of scab plate you use, straight vertical welds on your frame are a bad idea, the plate should be shaped like a diamond or curvy like the ones in the pic.
I feel that weld ons are more durable in the long run if installed correctly

 

how come straight vertical welds are bad ?

 

I think that it puts stress on the frame and it can break at the weld or something like that. I am sure someone else will chime in.

 

Hey 4rnr,how do the weld ons hold up here in the Chicago area with the salt and such?

 

I helped install a set of CBI sliders on one of the OHTTORA guy's Taco the other day, and have to say this is a pretty nifty way to install sliders. My only beef is that there are all those ridges to get hung up on where the U wraps under the frame - which would be even worse if you install the bolt in the bottom. I think it would be really cool to have the bottom of the U be one long piece connecting all the supports and providing a smooth surface.

One VERY important thing to consider is the design of the sliders. 4Crawler's are supposed to be VERY close to the body (my 4Crawler sliders are right up under the pinchweld) so there is no flexural force (moment, torque, whatever) applied to the frame, and all the mounts have to do really is support the weight of the slider (or you standing on the slider).

I'm also VERY curious as to the "no vertical welds". Is this 'cuz a lot of people can't do pure vertical welds very well? (Bottom to top, not the other way guys!)

 

This is a good article on frame welding,...... less typing for me, http://home.4x4wire.com/deddleman/section_welders.html

 

Found by using the blinking search button:

https://www.yotatech.com/forums/show...vertical+welds

See posts #42 and #46 specifically.

 

Ummm .. so they're saying spread the HAZ (heat affected zone) over more of the frame? and make longer welds to put more heat into the frame? Seems quite wrong to be, but, hey, I'm just a lowly metallurgist...

No offense to CBI and others, but I think the best way to protect the frame is to use Roger's (4Crawler) design and get the forces transferred right into the body mounts so nothing flexes.

 

I do offer a sleeved bolt option, that requires no welding and is only moderately more work to install:



http://www.4crawler.com/4x4/ForSale/...l#Installation

Also, if the holes have stripped out are near the bottom of the frame, a simple thru-bolt works fine. The lower web of the frame prevents crushing the frame along with a thick washer on the back side. Usually stripped self-tapping bolts are the result of not installing the bolt properly (i.e. hole drilled too large or bolt tightened too much), or by letting the bolt work loose after the intial installation (they should be checked after a few hundred miles of driving) to make sure that the brackets have not worked closer to the frame. This can happen if there is debris (dirt, rust, grease, paint) between the slider bracket and frame that falls out and leaves a small gap between the frame and bracket.

The brackets can also be tack welded as additional support. Some folks have bolted them on then run about an inch of weld bead along the bottom of the bracket to secure them in place. This way the weld can be ground out for slider removal if needed. One customer did this to prevent potential heft , as he works in a large city and often parks out on the city streets during the day. And of course, the bolt-on sliders can also be welded on.

I ran my first set of sliders with self-tapping bolts and had no issues in about 4 years of hard use, including a few Rubicon crossings:



And my current set use the sleeved lower bolts and tapped upper bolts and have worked out very well in 5 years of use on the 'Con, Moab, Fordyce, Hammers and Dusy trails: