Frame rivets to bolts

[alwaysFlOoReD]

Ford frame document pdf ;

http://www.therangerstation.com/forums/attachment.php?attachmentid=9158&d=1358836447

 

[Rex2nr]

Ranger frames were made from 1017 steel (low carbon - 36ksi yield).

Grade 8 bolts achieve their strength by being a medium carbon alloy heat treated steel. If you weld them post install installation; you are destroying the heat treatment; better to use lock-tite red.

I-Car collision repair states the rivets can be replaced with 7/16" Grade 8 bolts after enlarging hole for the 3/8" or 10mm rivet after torqued to 33-50 ft-lbs; the 7/16" or 12mm rivets replaced by 1/2" Grade 5 bolts torqued to 53-75 ft-lbs. The repair manual specifically cautions to avoid creating stress concentrations.*

I believe the gas tank bracket has 3/8" rivets.

*AlwaysFlOoReD posted Ford's document on frames a while back, but I can't find it this morning. It also cautions against adding too much strength in a location as that would cause stress concentrations.

AlwayFlOoReD was cautioning me about too much frame doubler/welding.

Thanks for the info.

I had tack welded one of the clips for the bumper to the frame since it tore to get the bolt off the truck. I then welded a nut to one of the bed bolts to get the bolt out since the torx bit rounded out the bolt head.

I will be installing grade 10.9 12x1.75x40mm bolts with loctite red in place of the rivets.

I had read through the frame document but mainly the parts on welding/strengthening. I do have a small section with some perforations, but it's up front on the boxed area by the cats, so I am less concerned than if it was the rail.

 

[85_Ranger4x4]

"Star" lockwashers for low-medium stress usually works. Split ones are likely usesless though. NASA did a study on that... Split washers made loosening worse in high-vibration situations. If I was to guess why, it's because of the spring action such washers use to lock. But, while I have an Engineering Technology degree (and am an engineer in the automotive manufacturing industry), the degree is in electrical, not mechanical so all I know is outside of school.

11 years ago when I was designing boom trucks the lead engineer said he wanted all lock washers removed from designs going forward since they do nothing and to just call out locktite.

Dunno about vibration, I think the spring is mainly to force the two edges out so they bite into the nut/bolt and surface to lock them together. When it is tight you have a lot more force going the in than a lockwasher can muster going the other direction. I have never really heard or read about it but that is how I came up with how it works.

The big problem I have ran into them over the years is they split on the backside too, the two halves fall away and you now have a huge gap and everything is loose. But most of the stuff I play with now that does that is 1940's/50's farm equipment... can't say the little lockwasher didn't do its duty. And they usually break when you are disassembling stuff anyway. It is vibration galore on this stuff, only thing with any isolation is the seat. If anything would make them work loose I think a unbalanced 4.3L 4cyl or a equally unbalanced 2.9 2 cyl would bring enough vibration to the party.

I am not doing truck frames or whatever but I don't have a problem with stuff coming loose.

 

[Mark_88]

Here is the link to the frame repair if anyone wants to have a look...post #6 by alwaysfloored...

http://www.therangerstation.com/forums/showthread.php?t=144556&highlight=frame+repair

Ooops...missed a whole bunch of posts...lol

 

[Rex2nr]

Have you guys seen Nord lock washers? My buddy uses these on his turbo CRX hill climb car.

https://www.youtube.com/watch?v=IKwWu2w1gGk

 

[85_Ranger4x4]

Have you guys seen Nord lock washers? My buddy uses these on his turbo CRX hill climb car.

https://www.youtube.com/watch?v=IKwWu2w1gGk

Those are pretty interesting, also note they did not compare steel lock nuts though.

 

[alwaysFlOoReD]

I think they go over steel lock nuts in another video. Basically, the lock nut resists vibration but doesn't overcome "slacking", where the metal compresses slightly over time and the bolt and nut loses "compressive friction - [my term]". I watched a second video of the "nordlock X", which adds a cone shape to one of the two washer pairs to combat "slacking".

 

[Mark_88]

Yes, very interesting...looks like it could make things tighter for the long run.

I've tried double nutting...but I didn't see a test on double nutting with a lock washer between the nuts...but I'd imagine it would slide if the lock washer slides.

 

[Rex2nr]

To follow up, I was able to replace the cross member. I bolted it in with 10x1.5x30mm and 35mm 8.8 bolts. My local Home Depot was short on stock for anything else. These fit perfectly, I just had to ream the holes out very slightly, basically to take the undercoating off.

I also had to repair the rear section of the frame, it had rotted out behind the leaf springs. Where the hitch bolts up was paper thin on the drivers side. I welded on some 3/16" plate to the rail sides, and 1/8" plate along the bottoms. I also built a cross member to replace the tire carrier, also rotten.

I tried to attach pics, but there is a security token missing and it won't allow me to.

 

[AllanD]

This is the only time that I have to dis-agree with AllenD. If the two pieces are not in contact with each other when tapping, there will be a vast amount of stress on the bolt and with no friction between the two pieces the hole could egg out over time. If you can clamp the two pieces together while tapping then it should be OK. Drilling and using the shank shoulder to fill the hole is easier and as strong, if not stronger IMO.

My right and doesn't work the way it used to so typing is rather tiresome...

But I often tap just tte frame rail, not what I'm bolting to it . There I often use an Aircraft frame reamer (an adjustable reamer) to enlarge the hole in body mount brackets and cross-members to an EXACT FIT of the bolt shank...

I also de-rust all surfaces and coat used to coat them with Zinc Chromate primer (when I still had any available)
Lately I use Aerosol bed-liner.

And like mentioned above I prefer all metal self-locking nuts

Common "Split-lock washers are only slightly better than useless

But while MAC points out that structural steel framing does not use locking nuts
The only structural steel that lives with the vibration of a light truck frame is a structural steel tower
at the Kennedy Space Launch facility, but I'd bet in terms of bolt loosening a Ranger
frame is worse... FAR worse!

As when a launch tower if vibrated it is only for a matter of 15-20 seconds and is then quiet for months

Nobody takes that launch tower out for an afternoon of washboard desert roads...

Or the even across the parking lot of my favorite U-pull-it junkyard
(let alone the 30mile drive (each way) to get there!)
AD

 

[alwaysFlOoReD]

But I often tap just tte frame rail, not what I'm bolting to it . There I often use an Aircraft frame reamer (an adjustable reamer) to enlarge the hole in body mount brackets and cross-members to an EXACT FIT of the bolt shank...

This makes sense.