Nothing Special's '71 Bronco

[Nothing Special]

If you intend to add fasteners after cure, at the very least dab some epoxy on the things and in the hole before you tighten it up.

But you have a lot of area, and if you get 100% fill (as shown by squeeze out when you lay a central bead) I think there's really nothing to worry about.

4x50 is 200 sq."

A little more progress today. I pulled the bottom of the fender flare forward until it swung up to the bottom of the 4x4 and it looked fine that way. So I trimmed the fender opening a little larger to match up with the new flare position, cut the tube off to match the new fender line and drilled a few new holes to mount the flare in its new position. I also welded in another 3/8" thick piece in the top of the tube to attached the rear fender (same as what I did for the front yesterday, so no new pictures) and drilled and tapped the holes in both plates to attach both fenders to the tube.

Otherwise I played around with clamping the tube in position (and ran into the issue with the inner rocker pulling away that I mentioned above). Still, it looks like I can get everything where it needs to be for either welding or adhesive, so I'm not stuck yet.

It was really mostly little putzy stuff, but it did get to the point where I had the tube essentially as it's going to be and in the right position. So a good time for some pictures.

Here's the front end of the tube.

Here's the rear end with the fender flare attached.

And here's the whole thing

[Gary Lewis]

A little more progress today. I pulled the bottom of the fender flare forward until it swung up to the bottom of the 4x4 and it looked fine that way. So I trimmed the fender opening a little larger to match up with the new flare position, cut the tube off to match the new fender line and drilled a few new holes to mount the flare in its new position. I also welded in another 3/8" thick piece in the top of the tube to attached the rear fender (same as what I did for the front yesterday, so no new pictures) and drilled and tapped the holes in both plates to attach both fenders to the tube.

Otherwise I played around with clamping the tube in position (and ran into the issue with the inner rocker pulling away that I mentioned above). Still, it looks like I can get everything where it needs to be for either welding or adhesive, so I'm not stuck yet.

It was really mostly little putzy stuff, but it did get to the point where I had the tube essentially as it's going to be and in the right position. So a good time for some pictures.

Here's the front end of the tube.

Here's the rear end with the fender flare attached.

And here's the whole thing

I think it looks great. And it'll sure be a whole lot more solid than what you had.

[ArdWrknTrk]

A little more progress today. I pulled the bottom of the fender flare forward until it swung up to the bottom of the 4x4 and it looked fine that way. So I trimmed the fender opening a little larger to match up with the new flare position, cut the tube off to match the new fender line and drilled a few new holes to mount the flare in its new position. I also welded in another 3/8" thick piece in the top of the tube to attached the rear fender (same as what I did for the front yesterday, so no new pictures) and drilled and tapped the holes in both plates to attach both fenders to the tube.

Otherwise I played around with clamping the tube in position (and ran into the issue with the inner rocker pulling away that I mentioned above). Still, it looks like I can get everything where it needs to be for either welding or adhesive, so I'm not stuck yet.

It was really mostly little putzy stuff, but it did get to the point where I had the tube essentially as it's going to be and in the right position. So a good time for some pictures.

Here's the front end of the tube.

Here's the rear end with the fender flare attached.

And here's the whole thing

Yep, I think the lines look fine too!

And Gary can better see how the wheel arch crease in the front fender lines up.

[Gary Lewis]

Yep, I think the lines look fine too!

And Gary can better see how the wheel arch crease in the front fender lines up.

Yes, the front fender, fender flare, and 4x4 line up nicely.

[Nothing Special]

.... The adhesive I used was SEM DUAL-MIX™ MULTI-PURPOSE PANEL ADHESIVE Part #39747. But SEM also makes DUAL-MIX™ STRUCTURAL IMPACT RESISTANT ADHESIVE

Part #39757

which might be a better fit. However, they both require use of a special gun, and you'll need to borrow one of those or buy it, and I think they may be expensive.

As I read up on adhesives I'm getting a little less excited about going that route.

First off, the difference between panel adhesives and structural adhesives. Gary touched on that in his post I quoted here, but after a little Googling I'm sure that I do not want to use panel adhesives. The strength seems to be lower than structural and they seem to be less able to handle impacts.

Structural adhesives seem very promising, but I'm seeing a split (if I'm seeing it right) between epoxies and MMAs (methyl methacrylates, not mixed martial arts, don't you just love TLAs (three-letter abbreviations)?). MMAs seem to be considered to be significantly superior to epoxies, and, in one video, 20% better than welding. I haven't seen a good comparison between epoxies and welding, but the two being separately compared to MMAs don't make epoxy seem like it's as good as welding.

So MMAs might seem like a good option, but one of their "advantages" is fast cure time (30 seconds to 30 minutes?) which makes it seem very unlikely that I'd have things positioned correctly and clamped well before I was stuck (literally).

Am I seeing something wrong or missing anything?

[ArdWrknTrk]

.... The adhesive I used was SEM DUAL-MIX™ MULTI-PURPOSE PANEL ADHESIVE Part #39747. But SEM also makes DUAL-MIX™ STRUCTURAL IMPACT RESISTANT ADHESIVE

Part #39757

which might be a better fit. However, they both require use of a special gun, and you'll need to borrow one of those or buy it, and I think they may be expensive.

As I read up on adhesives I'm getting a little less excited about going that route.

First off, the difference between panel adhesives and structural adhesives. Gary touched on that in his post I quoted here, but after a little Googling I'm sure that I do not want to use panel adhesives. The strength seems to be lower than structural and they seem to be less able to handle impacts.

Structural adhesives seem very promising, but I'm seeing a split (if I'm seeing it right) between epoxies and MMAs (methyl methacrylates, not mixed martial arts, don't you just love TLAs (three-letter abbreviations)?). MMAs seem to be considered to be significantly superior to epoxies, and, in one video, 20% better than welding. I haven't seen a good comparison between epoxies and welding, but the two being separately compared to MMAs don't make epoxy seem like it's as good as welding.

So MMAs might seem like a good option, but one of their "advantages" is fast cure time (30 seconds to 30 minutes?) which makes it seem very unlikely that I'd have things positioned correctly and clamped well before I was stuck (literally).

Am I seeing something wrong or missing anything?

My father was director of engineering at three companies that specialized in PolyMethylMethAcrylate.

Acrylic.... or commonly "Plexiglas"

Polycast

Everkleer

Cast Optics

Acrylics have very high bond strength, but are suceptable to brittle fracture.

That's why impact guards, face shields, etc, are made from Polycarbonate "Lexan"

Acrylic adhesive is used on foil tape and many other permanent installations.

It's surely the catalyst, or the amount of catalyst that's causing it to kick that fast.

While fine for a production environment you may well need to cool the 4x4 to get the working life you want.

But again, with that much surface area I wouldn't hesitate to use epoxy.

[Nothing Special]

My father was director of engineering at three companies that specialized in PolyMethylMethAcrylate.

Acrylic.... or commonly "Plexiglas"

Polycast

Everkleer

Cast Optics

Acrylics have very high bond strength, but are suceptable to brittle fracture.

That's why impact guards, face shields, etc, are made from Polycarbonate "Lexan"

Acrylic adhesive is used on foil tape and many other permanent installations.

It's surely the catalyst, or the amount of catalyst that's causing it to kick that fast.

While fine for a production environment you may well need to cool the 4x4 to get the working life you want.

But again, with that much surface area I wouldn't hesitate to use epoxy.

Finally some more progress! I've been stuck waiting to get the 1" round tube bent for the rash bars. I finally was able to pick them up yesterday, so I could get back to work. I had asked for 3/16" wall tubing, but it ended up being .200" thick. Oh well, it's only 1/2 lb heavier.

Yesterday I drilled eight 1" holes through both sides of the 4x4 so I could mount the stand-offs to support the rash bar (pictures below will explain it better). I also fish-mouthed the stand-offs to fit against the rash bar. Here are the results of yesterday's machining:

And here are the stand-offs going through the 4x4:

And one with the rash bar clamped in place to the 4x4 held in place with a jack:

So tonight it was time to weld the rash bar to the 4x4. After getting everything cleaned up it was fun (not) trying to get everything clamped in place

Once that was set I fired up the welder again. I got beautiful welds on the inner end of the stand-offs! But these are the welds that need to be ground flat and will be where no one can ever see them, so that doesn't really matter.

The welds on the outside, the ones that I don't plan to grind down and which are visible, well, they'll hold.

Then I was able to weld the cap on the back end of the 4x4

So now I'm done making the rocker! Next will be to get everything prepped to attach them to the tub. After a lot of thought I'm planning on going back to plan A and plug-welding them on. I know that adhesive would be better at preventing corrosion, and it might hold better too. But I'm still not comfortable with the way the inner rockers would be pulling away. And I'm also not completely comfortable with the impact strength or the working time. So while I believe adhesive might be better than welding, I'm also afraid that it might be worse, and I'm pretty confident that welding will be good enough. Plus I have what I need to weld it already.

[Gary Lewis]

Finally some more progress! I've been stuck waiting to get the 1" round tube bent for the rash bars. I finally was able to pick them up yesterday, so I could get back to work. I had asked for 3/16" wall tubing, but it ended up being .200" thick. Oh well, it's only 1/2 lb heavier.

Yesterday I drilled eight 1" holes through both sides of the 4x4 so I could mount the stand-offs to support the rash bar (pictures below will explain it better). I also fish-mouthed the stand-offs to fit against the rash bar. Here are the results of yesterday's machining:

And here are the stand-offs going through the 4x4:

And one with the rash bar clamped in place to the 4x4 held in place with a jack:

So tonight it was time to weld the rash bar to the 4x4. After getting everything cleaned up it was fun (not) trying to get everything clamped in place

Once that was set I fired up the welder again. I got beautiful welds on the inner end of the stand-offs! But these are the welds that need to be ground flat and will be where no one can ever see them, so that doesn't really matter.

The welds on the outside, the ones that I don't plan to grind down and which are visible, well, they'll hold.

Then I was able to weld the cap on the back end of the 4x4

So now I'm done making the rocker! Next will be to get everything prepped to attach them to the tub. After a lot of thought I'm planning on going back to plan A and plug-welding them on. I know that adhesive would be better at preventing corrosion, and it might hold better too. But I'm still not comfortable with the way the inner rockers would be pulling away. And I'm also not completely comfortable with the impact strength or the working time. So while I believe adhesive might be better than welding, I'm also afraid that it might be worse, and I'm pretty confident that welding will be good enough. Plus I have what I need to weld it already.

They look great! Well done! The curves and the fish-mouths make it look professional. And, it is stout.

As for welding vs adhesive, I can easily see the debate, and I think welding will be great.

[ArdWrknTrk]

Finally some more progress! I've been stuck waiting to get the 1" round tube bent for the rash bars. I finally was able to pick them up yesterday, so I could get back to work. I had asked for 3/16" wall tubing, but it ended up being .200" thick. Oh well, it's only 1/2 lb heavier.

Yesterday I drilled eight 1" holes through both sides of the 4x4 so I could mount the stand-offs to support the rash bar (pictures below will explain it better). I also fish-mouthed the stand-offs to fit against the rash bar. Here are the results of yesterday's machining:

And here are the stand-offs going through the 4x4:

And one with the rash bar clamped in place to the 4x4 held in place with a jack:

So tonight it was time to weld the rash bar to the 4x4. After getting everything cleaned up it was fun (not) trying to get everything clamped in place

Once that was set I fired up the welder again. I got beautiful welds on the inner end of the stand-offs! But these are the welds that need to be ground flat and will be where no one can ever see them, so that doesn't really matter.

The welds on the outside, the ones that I don't plan to grind down and which are visible, well, they'll hold.

Then I was able to weld the cap on the back end of the 4x4

So now I'm done making the rocker! Next will be to get everything prepped to attach them to the tub. After a lot of thought I'm planning on going back to plan A and plug-welding them on. I know that adhesive would be better at preventing corrosion, and it might hold better too. But I'm still not comfortable with the way the inner rockers would be pulling away. And I'm also not completely comfortable with the impact strength or the working time. So while I believe adhesive might be better than welding, I'm also afraid that it might be worse, and I'm pretty confident that welding will be good enough. Plus I have what I need to weld it already.

Great job, man!

They look really stout.

[Nothing Special]

.... And, it is stout....

.... They look really stout....

What's the line? If that's a compliment I thank you!

Seriously, I got the "great job" and "well done" in the replies, and I definitely thank you. But I've also received comments that these will lower my cg significantly! It is a little heavy (about 50 lbs by my calculations), but no heavier than the aftermarket rocker guards I bought a while back but couldn't use (they were intended to screw to the stock rockers, and mine were already too rusted away for that).

And yes, it is stout!