3rd Gen IFS skidplate buildup

[glenyoshida]

Uggh I feel your pain. I've had a few pieces that I had to scrap because of warping. On one project I made the tolerances so tight that I had to make the same piece 4 times before getting it.
If you don't mind me volunteering the suggestions, I'd like to help you figure out what went awry on the skid before you weld on the new one. Especially if you have to do the same welds. I've had to put projects on the shelf for weeks from getting so irritated. Are you going to have to weld steel on the plate in a T joint again?

[Seanz0rz]

yes, welding a T joint, although i guess its not a real T. i will be welding on each side, single pass. basically i will put a magnet to hold it in place, do 4 tacks, 2 on each side. start welding in 1 inch passes starting from top to bottom, alternating sides and letting it cool in between. i dont know if ill do a full weld, i might just do 1 inch weld, 1` inch blank.

i know my problem, i went way to fast. i was in a huge hurry to get it done, and it ended up costing me several days worth of work...

any advise is greatly appreciated! i wont be working on this until wednesday at the earliest, more likely the weekend (depends on weather, downside of outdoor workshops)

[4x4mike]

I think the 3/8 like Budbuilt was over 3 bills.

bud built is 3/16th

That's what I meant, I've never been good with fractions.

[freejake3]

Hey Sean

My 2cents on warpage (seeing as how I had to learn the hard way). Take some flat-bar or any other scrape metal that covers your skid along its greatest length and tack weld them on. ALong with this preventative measure you can additonally tack the entire piece to your welding table and then start your welds. Both of these should keep it from warping out of control. Of course your change to a slower welding pace will probably help the most. A wet towel to cool the welds down will keep you moving along as well. Good luck.

See you at Superstition

[glenyoshida]

When you mentioned that it was worse the 2nd time after you were going very slowly it could indicate that you're getting the weld puddle bigger than necessary. You need the weld penetration but if you were to cut a cross section away you want the weld to form a connection as in this pic

Notice how the bead makes a connection between the two pieces roughly the same thickness as the sheet. Try and ride this fine line so you get just enough weld penetration.


If you are getting burn through on the back side of the weld as this guy did in a single spot in this photo then you are putting too much heat into the weld and that makes for lots more movement in the metal.




Before you get too far on your redeux take some of that scrap that you have and reweld some T Joints for practice. This will give you as much practice as you need so you can avoid warping another skid plate.

You mentioned doing 2 tacks on each side then stitching your weld beads in 1" lengths. You can benefit from many more tacks. Try ten tacks on each side of the brace so twenty total. Your tacks should have the same penetration as a regular bead. Often people make their tacks with just enough metal to hold things in place. That's fine for most projects but your tacks are actually holding things in shape so they are important.

I think you are on the right track with stitching. Since your welds shouldn't be life threatening if they fail, I'd suggest that you do just that. Instead of the 1" bead then a blank. Try 1/2" bead and leave a 2" blank. That will give you roughly 6" of total weld bead on both sides of the joint. It may not seem like a lot but even mild steel has a tensile strength of around 70,000 psi and you'll have at least two square inches of steel in your welds. In a theoretical world where things are perfect if it took a tenth of a second for a rock to rip off the skid you could be going around 20 MPH before the welds failed. Never works that way in real life though but I digress lol.

As a final thing to keep the warping under control, as you finish a bead, take a ball peen hammer or better yet an air hammer and pound into the weld. The impact will create tiny movements in the weld and help compensate for the shrinkage. Many smaller impacts are better than just a few big hits. You do have to whack it pretty good though. If you aren't deforming the metal in the bead just a little bit then you aren't relieving the stress. Check to see how true your plate is as you go along.

And above all good luck! I really do feel your pain. I cringe remembering my own projects thus far.

Oh and FWIW I like the cutouts that match the bumper.

[4x4mike]

FWIW I stitch welded in 1/2- 3/4" sections to prevent warping. As you look at the skid plate I would weld a section on the left, then the right, then somewhere more left then somewhere more right alternating around. Each weld was quick and deliberate. This was my first real project so I took it slow. Grab a couple of dr peppers and go welding. Weld, drink, weld, drink.

[Seanz0rz]

thanks for the tips guys! hopefully this all helps someone else researching welding and whatnot!

and mike, its diet dr. pepper for me!

[Seanz0rz]

yeah, its been a LONG time since ive updated this, because its been a LONG time since i touched the skidplate. lots of reasons, none worth mentioning...

so i got back on it today. one thing i was never pleased with on the original was the mounting points for the rear. this time i set out to change that. i cut a piece of angle iron, measured 3 or 4 times, drilled the holes, PERFECT! so i bolted it up to the cross member:


i put the skid up and im STILL hitting the mangled front cross member on the right side (less mangled side), so i just notched the cross member, its getting removed soon anyway.


putting the skid up, i noticed that the driverside brace is not where it should be, but about 1/4 inch out. cut the tacks and retack it where it SHOULD be.


once that was out of the way, i could get the skid up in place to measure where to notch for the angle iron. cut out the notch and it was still not right, took me a half dozen tries to get it right.


this is what i tacked:


my welder plug is actually in my back yard (next to the service entrance) and running wire to the driveway or garage is just a bit too $$$. so to weld on the driveway, i have to pull out our 10kW generator.


all that set up for two TINY tacks just to take all of it and go weld in the backyard off house power.

also grabbed a picture of the truck. GAWD shes sexy! been looking at alot of different cars so i can take her off daily driver duty, but alot of me doesnt want to!


more updates tonight hopefully. yeah i know about the surface rust. unfortunately it sat outside for the last 3 months. it will get either stripped with a wheel before i weld, or coated and cleaned with naval jelly all before i paint. everything is staying tacked for now.

[DHC6twinotter]

[Seanz0rz]

ok so more updates. after getting it tacked on the truck, i pulled it off, took it to the back yard, and started tacking on the braces/gussets. if i was to do it again i would turn the angle around so more of it was in contact with the 3 longitudinal braces. after tacking it well (better than the pictures indicate, i refitted it to the vehicle, everything lined up!!! so i went off to weld. the rear mount is now nearly completely done welding, just a couple of welds to do, require me to turn the piece so i can weld it properly (not great at vertical welds...) and im SLOWLY welding up the braces. im about half done. add in a few more gussets, clean up some corners, and add a bracket for the rear plate, and im DONE! its getting close. so now for the pictures.

this gusset is cut around half of the brace, should be super strong once welded:


rest is scrap i had lying around, still looks good i think:



welded:





oh im aware that the rear mount isnt technically centered on the skidplate. thats ok, i actually drilled the holes slightly off center, so everything appears to be square.