lots of inspiration from Blaine’s method. A few more pictures to reference.
Sab-a-dab-a-doo! The back-country LJ build has officially started
- Thread starter sab
- Start date
lots of inspiration from Blaine’s method. A few more pictures to reference.
OP
Today, I actually started on the to do list for this build with #1 - fixing the broken fuel filler nipple on the fuel tank. It was likely broken when I installed the body lift. This repair is no longer required because Mr. Blaine sold me a good used tank at a very fair price (see Post #43). However, I wanted to see if repair was feasible, and if so, I'll have a good spare tank. I started by researching plastic welding.
Oddly enough, my plastic welding journey began about 34 years ago. I had just quit grad school to pursue a career in motorcycle racing (as an engineer, not a rider), and I was hanging out at the race track with club racers and riding sport bikes on the street. The bodywork on the race bikes was fiberglass, and repairing fiberglass was pretty straightforward; however, repairing the OEM ABS plastic bodywork was a new process. Back then, plastic welders used heated nitrogen or compressed air, and they were very expensive for a just-graduated engineer. I did some research on the machines and the process, but I couldn't afford the machines, so none of that research evolved into practical application.
My new journey started with researching how the process and equipment has changed in the 34 years since. I started with determining what kind of plastic the filler nipple is made from. I know from my previous work that plastic fuel tanks typically have the plastic types noted on the tank via mold notes, so I found that note on my tank:
The "PE-HD" is high-density polyethylene, the "PE-LD" is low-density polyethylene, and the EVOH is an ethylene vinyl alcohol copolymer. Oddly, the normal acronyms for the two polyethylenes is LDPE and HDPE. I don't know why Chrysler used the other acronyms. The tank body itself is actually a multi-layer design. Both of the polyethylenes are not impervious to gasoline vapors (the vapors can seep through it), so the EVOH is used in the middle in order to pass EPA tests. The filler nipple is welded to the tank body, and it is a single layer, molded part. It's made from one of the two polyethylenes, but I was not able to determine which one. Fortunately, both can be welded with LDPE filler.
After determining what kind of plastic I needed to weld, I started new research on plastic welding technology. I discovered that the heated gas systems are still very expensive, but glorified soldering iron technology (now called "airless plastic welding") has progressed and seemed a lower cost possibility. I ended up purchasing a MiniWeld Model 7 Airless Plastic Welding Kit made by Polyvance:
The kit contains the iron with temp controller, a stand, a cleaning brush, a bunch of different filler materials, and some stainless steel screen material to use for reinforcement. I decided to practice first. I knew that the every day five-gallon bucket is made from HDPE, so I punched a couple holes in one and proceeded to repair it. I didn't take many photos of the process. I tried the tip that has a feed hole in it for the filler rod, but I found that to be cumbersome, so I just used the spade-shaped tip shown above and melted the filler directly on/into it. It turned out well (not pretty, though), and it doesn't leak water:
This is the filler used (LDPE - HDPE filler is not available):
With the testing complete, I decided to tackle the tank nipple repair. Here's the problem:
After using a rotary tool with a brush to clean things up, I cut and formed a piece of the stainless steel screen material to use to reinforce the repair:
The idea is to use the iron to melt the screen into the existing plastic and then cover it with melted filler material. To hold it in place while melting it in, I used a needle-nosed locking pliers:
Unfortunately, I don't have any pictures of the actual welding process because I only have two hands, and I don't have a tripod, so I'll just describe it. The iron has convenient material settings on the dial, so I set it to "PE", for polyethylene, and used the tip to melt the plastic through the screen to imbed the screen into the existing plastic. I immediately melted a layer of filler material over that, and then repeated multiple times to build up a radius like so:
I'm actually surprised how sturdy it feels! When I load it by hand in the upward direction (the same load direction that broke it), I can see the part of the black tank outside the welded ring deflecting instead of the nipple. I think I have a decent spare tank!
The final step in the process was to smoke test the tank to make sure it wouldn't leak through the repair area, and it passed with flying colors. Here's a picture from the smoke testing:
Overall, it was a successful day. Tomorrow, I'm going to wash the LJ and put a cover on it. It lives in the shop, and my shop activities generate a LOT of dust, so I bought a cover for it while I'm working on it because the paint is in pretty good condition (not to mention the half doors, GR corners, and hood cowl have new-ish paint on them). After that, I'm going to tackle to-do list item number 2 - attempt to reinforce the top of the radiator tank where the common crack failures occur. My LJ has 55,000 miles on it, and it's the original, 19-year-old radiator. I have a spare OEM radiator, but I'd like to get as much life out of the original one as possible. Instead of plastic welding, I'm going to try a two-part epoxy kit (made by Versachem). I don't know if it'll work, so stay tuned!
Oddly enough, my plastic welding journey began about 34 years ago. I had just quit grad school to pursue a career in motorcycle racing (as an engineer, not a rider), and I was hanging out at the race track with club racers and riding sport bikes on the street. The bodywork on the race bikes was fiberglass, and repairing fiberglass was pretty straightforward; however, repairing the OEM ABS plastic bodywork was a new process. Back then, plastic welders used heated nitrogen or compressed air, and they were very expensive for a just-graduated engineer. I did some research on the machines and the process, but I couldn't afford the machines, so none of that research evolved into practical application.
My new journey started with researching how the process and equipment has changed in the 34 years since. I started with determining what kind of plastic the filler nipple is made from. I know from my previous work that plastic fuel tanks typically have the plastic types noted on the tank via mold notes, so I found that note on my tank:
The "PE-HD" is high-density polyethylene, the "PE-LD" is low-density polyethylene, and the EVOH is an ethylene vinyl alcohol copolymer. Oddly, the normal acronyms for the two polyethylenes is LDPE and HDPE. I don't know why Chrysler used the other acronyms. The tank body itself is actually a multi-layer design. Both of the polyethylenes are not impervious to gasoline vapors (the vapors can seep through it), so the EVOH is used in the middle in order to pass EPA tests. The filler nipple is welded to the tank body, and it is a single layer, molded part. It's made from one of the two polyethylenes, but I was not able to determine which one. Fortunately, both can be welded with LDPE filler.
After determining what kind of plastic I needed to weld, I started new research on plastic welding technology. I discovered that the heated gas systems are still very expensive, but glorified soldering iron technology (now called "airless plastic welding") has progressed and seemed a lower cost possibility. I ended up purchasing a MiniWeld Model 7 Airless Plastic Welding Kit made by Polyvance:
The kit contains the iron with temp controller, a stand, a cleaning brush, a bunch of different filler materials, and some stainless steel screen material to use for reinforcement. I decided to practice first. I knew that the every day five-gallon bucket is made from HDPE, so I punched a couple holes in one and proceeded to repair it. I didn't take many photos of the process. I tried the tip that has a feed hole in it for the filler rod, but I found that to be cumbersome, so I just used the spade-shaped tip shown above and melted the filler directly on/into it. It turned out well (not pretty, though), and it doesn't leak water:
This is the filler used (LDPE - HDPE filler is not available):
With the testing complete, I decided to tackle the tank nipple repair. Here's the problem:
After using a rotary tool with a brush to clean things up, I cut and formed a piece of the stainless steel screen material to use to reinforce the repair:
The idea is to use the iron to melt the screen into the existing plastic and then cover it with melted filler material. To hold it in place while melting it in, I used a needle-nosed locking pliers:
Unfortunately, I don't have any pictures of the actual welding process because I only have two hands, and I don't have a tripod, so I'll just describe it. The iron has convenient material settings on the dial, so I set it to "PE", for polyethylene, and used the tip to melt the plastic through the screen to imbed the screen into the existing plastic. I immediately melted a layer of filler material over that, and then repeated multiple times to build up a radius like so:
I'm actually surprised how sturdy it feels! When I load it by hand in the upward direction (the same load direction that broke it), I can see the part of the black tank outside the welded ring deflecting instead of the nipple. I think I have a decent spare tank!
The final step in the process was to smoke test the tank to make sure it wouldn't leak through the repair area, and it passed with flying colors. Here's a picture from the smoke testing:
Overall, it was a successful day. Tomorrow, I'm going to wash the LJ and put a cover on it. It lives in the shop, and my shop activities generate a LOT of dust, so I bought a cover for it while I'm working on it because the paint is in pretty good condition (not to mention the half doors, GR corners, and hood cowl have new-ish paint on them). After that, I'm going to tackle to-do list item number 2 - attempt to reinforce the top of the radiator tank where the common crack failures occur. My LJ has 55,000 miles on it, and it's the original, 19-year-old radiator. I have a spare OEM radiator, but I'd like to get as much life out of the original one as possible. Instead of plastic welding, I'm going to try a two-part epoxy kit (made by Versachem). I don't know if it'll work, so stay tuned!
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OP
For those following this thread/build, I keep track of the weight of components. I went back to the first post and revised it. If I had recorded the weights, I listed the effect of each change on the vehicle weight in the directory in that first post. I will continue to do this because it's helpful to see how changes affect the rig's weight.
OP
Today, I started the morning by washing the LJ before putting a full cover on it to keep the abrasive dust off it while it's in the shop for the build. No pictures, sorry. Then, I moved on to to-do list item #2: I made an attempt to prevent this from happening in the future:
That picture is from my buddy @06LJR's LJ last July, but I bet I've seen 3 or 4 nearly identical failures in the ~3 years I've been on the forum. I did flush the cooling system when I bought the LJ two summers back, and I have a spare, new Mopar radiator waiting in the wings. However, I'd like this radiator to last as long as possible. I wanted to somehow reinforce that area before it cracks. Plastic welding on radiator tanks is not usually successful, which left me with an epoxy solution. After researching a bit, I found this kit to have the best reviews:
Using the kit is simple. You clean the area, sand it, clean it again (I used acetone both times), cut the fiberglass cloth to fit the area, mix the expoxy, and apply it over/through the fiberglass. Some observations:
And here's the finished product (the fiberglass is in there if you look closely):
The amount of fiberglass in the kit is only enough to do half the top of the radiator, so I used two full kits. I bought them at my local O'Reilly's, and I think they were about $20 each.
Time will tell if this was worth the $40 and 45 minutes spent on it...
Next weekend, I have Monday and Tuesday off, and I plan to start on the rear frame raise (#3 on the to-do list).
That picture is from my buddy @06LJR's LJ last July, but I bet I've seen 3 or 4 nearly identical failures in the ~3 years I've been on the forum. I did flush the cooling system when I bought the LJ two summers back, and I have a spare, new Mopar radiator waiting in the wings. However, I'd like this radiator to last as long as possible. I wanted to somehow reinforce that area before it cracks. Plastic welding on radiator tanks is not usually successful, which left me with an epoxy solution. After researching a bit, I found this kit to have the best reviews:
Using the kit is simple. You clean the area, sand it, clean it again (I used acetone both times), cut the fiberglass cloth to fit the area, mix the expoxy, and apply it over/through the fiberglass. Some observations:
- The epoxy comes in a plastic pouch as two parts, separated by a seal. Mixing is very convenient because the internal seal between the two parts can be "popped" by squeezing one side. Once popped, you quickly (yes, I do mean quickly) mix it, cut the corner, and squeeze it out. Very clean and easy, with little cleanup required!
- This stuff sets up very quickly - like 5 minute epoxy. Don't dawdle - get 'er done!
- The mixing creates an exothermic reaction, and the pouch and epoxy gets very, very hot - enough to burn. Take care!
And here's the finished product (the fiberglass is in there if you look closely):
The amount of fiberglass in the kit is only enough to do half the top of the radiator, so I used two full kits. I bought them at my local O'Reilly's, and I think they were about $20 each.
Time will tell if this was worth the $40 and 45 minutes spent on it...
Next weekend, I have Monday and Tuesday off, and I plan to start on the rear frame raise (#3 on the to-do list).
OP
I started the rear frame raise project this weekend. I decided to attempt to do it matching the factory bend radii for the frame beams (more to come on that). I'm also going to make the bumper part of the frame to keep the rear-end shorter. I started this project by marking the frame for the cut:
I then started the cut using a jigsaw:
Then I went old-school and finished up with a hacksaw:
And done!
After cutting it off, I cut the rear cross-member off to prepare for the bumper replacing it (the plasma torch worked well for this):
And that's as far as I got this weekend. I have Memorial Day off, but I have other tasks to do tomorrow. I took Tuesday off, too, and I hope to get back to this then.
Continued in Post #90
I then started the cut using a jigsaw:
Then I went old-school and finished up with a hacksaw:
And done!
After cutting it off, I cut the rear cross-member off to prepare for the bumper replacing it (the plasma torch worked well for this):
And that's as far as I got this weekend. I have Memorial Day off, but I have other tasks to do tomorrow. I took Tuesday off, too, and I hope to get back to this then.
Continued in Post #90
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OP
I've had a lot going on the last few weeks, and I haven't had time for LJ projects in the shop. I did design a bunch of parts for the rear frame raise project, though, but I'm still waiting for some of those from the machine shop. I'll probably make some progress on that in the shop this weekend, and I'll continue the previous post then. For this morning, though, I switched it up a bit.
I purchased some new-in-box Hutchinson Rock Monster wheels from @Bigfoot-NM way back around Thanksgiving 2021. They've been sitting in boxes ever since. I didn't want to buy tires to just sit and time out, but now that I've started the build, I decided to buy them so that I am building with the proper size tires. I found a good price on some 35 x 12.5 x 15 KM3s a couple weeks ago, so today was "mount tires on beadlocks" day:
The Hutchinson Rock Monsters are double beadlock wheels. There are two halves that are pulled together with 15 studs and nuts. There is a large cylindrical rubber piece (seen above sitting in front of the tire in the forefront on the right) that goes inside the tire, and when you tighten the nuts on the studs, the two wheel halves pull together and pinch the beads of the tire between the lips on the wheels (similar to the Coyote beadlocks). The first step is to cram those rubber cylinders in the tires and lube one side of the tire for insertion of the inside wheel half. Look closely, and you'll see it inside the tire:
Likewise, you lube the lip on the inner half:
Then you insert the inner half in the tire:
I decided to install all of them with the valve stem in the same location on the tire, so that I could see if the tires slip on the wheels over time:
Next, you flip the tire over to insert the outer wheel half. There's an o-ring groove on the inner wheel half where a large o-ring gets inserted so that you don't loose air out of the seam between the two wheel halves. I didn't take a picture, but after you flip the wheel, you place the o-ring in the groove that's visible on the outside of the studs in this picture:
More lube on the other tire bead and wheel lip:
To properly align the two halves, the hole in the inner half I pointed to three pictures up lines up with a paint mark on the outer half (sadly, I did not take a picture). That puts the valve stem directly across from one of three long studs (more on why three are longer next). Once aligned properly, insert the outer half as far as possible:
There are three long studs that allow you to easily bring the two halves together, pinching the beads to the wheel lips. I put a 2x4 under the wheel so that I could push against it and thread the three nuts on and drive them completely down a little at a time:
A note about the nuts: the nuts used are a two-piece split nut with steps in it. The purpose of the split and the steps is to prevent loosening. I didn't really take a great picture of the nuts before installation, but in this as-installed picture, you can see the split and the step that locks the two halves together:
Next, you install the remaining nuts on the short studs and torque them to 100 ft-lb:
And the final step is to install the center caps and the cheesy plastic caps on the studs (I special ordered green caps, since OD green is an accent color in my build). These stud caps are my only complaint with these very nicely made wheels. The spotface on the wheel is too small for the caps once mis-alignment is accounted for. This results in some of them not seating (see the arrow showing how it's not seated below):
I'm confident that these that don't seat are going to fall off in short order, so I'm going to painstakingly inspect them and sand the O.D. down on my disc sander so that they seat. This process will be tedious - for five wheels, I have 75 caps!
Finally, here's a picture with the wheels installed:
One final note. I was planning on putting Counteract balancing beads in the wheels through the valve stem after I was done since I've heard that balancing the Hutchinson wheels is challenging. However, once I was all done (of course - why didn't I think of it at the start), I realized that with the rubber cylinder inside the wheels, there are two separate air chambers in the wheels, with two large holes, about 1/2" in diameter, in the rubber cylinder to equalize pressure throughout the tire. The valve stem leads to the inner, much smaller chamber. The beads will be inside the smaller chamber, close to the rim, rather than out at the outer edge of the tire where they are supposed to be. I don't know if they'll eventually find there way through the two holes and out to the outer chamber. Centrifugal force will want to put them there, but each one will have to roll past one of the two holes to get there. Now I'm not sure if I want to try them because if they don't get to the outer chamber, I think I'll have issues, and then I'll have to disassemble the wheels to remove the beads. I guess I'll try having someone balance them.
I purchased some new-in-box Hutchinson Rock Monster wheels from @Bigfoot-NM way back around Thanksgiving 2021. They've been sitting in boxes ever since. I didn't want to buy tires to just sit and time out, but now that I've started the build, I decided to buy them so that I am building with the proper size tires. I found a good price on some 35 x 12.5 x 15 KM3s a couple weeks ago, so today was "mount tires on beadlocks" day:
The Hutchinson Rock Monsters are double beadlock wheels. There are two halves that are pulled together with 15 studs and nuts. There is a large cylindrical rubber piece (seen above sitting in front of the tire in the forefront on the right) that goes inside the tire, and when you tighten the nuts on the studs, the two wheel halves pull together and pinch the beads of the tire between the lips on the wheels (similar to the Coyote beadlocks). The first step is to cram those rubber cylinders in the tires and lube one side of the tire for insertion of the inside wheel half. Look closely, and you'll see it inside the tire:
Likewise, you lube the lip on the inner half:
Then you insert the inner half in the tire:
I decided to install all of them with the valve stem in the same location on the tire, so that I could see if the tires slip on the wheels over time:
Next, you flip the tire over to insert the outer wheel half. There's an o-ring groove on the inner wheel half where a large o-ring gets inserted so that you don't loose air out of the seam between the two wheel halves. I didn't take a picture, but after you flip the wheel, you place the o-ring in the groove that's visible on the outside of the studs in this picture:
More lube on the other tire bead and wheel lip:
To properly align the two halves, the hole in the inner half I pointed to three pictures up lines up with a paint mark on the outer half (sadly, I did not take a picture). That puts the valve stem directly across from one of three long studs (more on why three are longer next). Once aligned properly, insert the outer half as far as possible:
There are three long studs that allow you to easily bring the two halves together, pinching the beads to the wheel lips. I put a 2x4 under the wheel so that I could push against it and thread the three nuts on and drive them completely down a little at a time:
A note about the nuts: the nuts used are a two-piece split nut with steps in it. The purpose of the split and the steps is to prevent loosening. I didn't really take a great picture of the nuts before installation, but in this as-installed picture, you can see the split and the step that locks the two halves together:
Next, you install the remaining nuts on the short studs and torque them to 100 ft-lb:
And the final step is to install the center caps and the cheesy plastic caps on the studs (I special ordered green caps, since OD green is an accent color in my build). These stud caps are my only complaint with these very nicely made wheels. The spotface on the wheel is too small for the caps once mis-alignment is accounted for. This results in some of them not seating (see the arrow showing how it's not seated below):
I'm confident that these that don't seat are going to fall off in short order, so I'm going to painstakingly inspect them and sand the O.D. down on my disc sander so that they seat. This process will be tedious - for five wheels, I have 75 caps!
Finally, here's a picture with the wheels installed:
One final note. I was planning on putting Counteract balancing beads in the wheels through the valve stem after I was done since I've heard that balancing the Hutchinson wheels is challenging. However, once I was all done (of course - why didn't I think of it at the start), I realized that with the rubber cylinder inside the wheels, there are two separate air chambers in the wheels, with two large holes, about 1/2" in diameter, in the rubber cylinder to equalize pressure throughout the tire. The valve stem leads to the inner, much smaller chamber. The beads will be inside the smaller chamber, close to the rim, rather than out at the outer edge of the tire where they are supposed to be. I don't know if they'll eventually find there way through the two holes and out to the outer chamber. Centrifugal force will want to put them there, but each one will have to roll past one of the two holes to get there. Now I'm not sure if I want to try them because if they don't get to the outer chamber, I think I'll have issues, and then I'll have to disassemble the wheels to remove the beads. I guess I'll try having someone balance them.
One final note. I was planning on putting Counteract balancing beads in the wheels through the valve stem after I was done since I've heard that balancing the Hutchinson wheels is challenging. However, once I was all done (of course - why didn't I think of it at the start), I realized that with the rubber cylinder inside the wheels, there are two separate air chambers in the wheels, with two large holes, about 1/2" in diameter, in the rubber cylinder to equalize pressure throughout the tire. The valve stem leads to the inner, much smaller chamber. The beads will be inside the smaller chamber, close to the rim, rather than out at the outer edge of the tire where they are supposed to be. I don't know if they'll eventually find there way through the two holes and out to the outer chamber. Centrifugal force will want to put them there, but each one will have to roll past one of the two holes to get there. Now I'm not sure if I want to try them because if they don't get to the outer chamber, I think I'll have issues, and then I'll have to disassemble the wheels to remove the beads. I guess I'll try having someone balance them.
Hindsight is always 20/20. Should have just dumped em in before you installed the outer half’
OP
OP
Today, I continued the rear frame raise project. I decided to match the factory bend radius, which is tedious, but I'm hoping it results in a modification that's hard to detect. To do so, I'll cut the frame as the green lines shown below, and then I'll cut new pieces from a piece of tubing as the purple lines show below:
By cutting the purple pieces from a piece of tubing, they'll have a radius on the corners. It won't match perfectly, due to the distortion the frame sees during bending, but I'll have to blend it after welding. Here are the pieces I cut with a jigsaw from a piece of 2.5" x 5" tubing:
To bend them, I designed a jig using AutoDesk's Fusion 360 software and had SendCutSend make the pieces. The jig uses the tab-and-slot design, similar to my weld/fab table show above. To bend the pieces, I'll use my oxy-acetylene torch with a rosebud tip. Here are the jig pieces laser cut:
Next, I welded the tab-and-slots, one layer at a time:
Stacking:
And complete:
The four holes in the jig match the 2" on center 5/8" holes of my weld/fab table so that I can anchor it to the table (these weld/fab tables are excellent!) I use these bushings with a screw to do so:
Here's the jig fastened to the table:
The slots in the end of the jig hold the pieces cut from the tubing, one on each side of the jig. Here's the bottom piece:
And the top piece:
I can't take photos while using the torch, but I heated each piece red hot and used C-clamps to form them to the curves of the jig, like this:
After cleaning them up, they turned out pretty good. Here's a bottom piece, ready for welding:
It's hard to see in that photo, but there's a 45° bevel on the bottom edge for welding the butt seam. This is as far as I got today. Stay tuned for the cutting of the frame pieces and welding.
By cutting the purple pieces from a piece of tubing, they'll have a radius on the corners. It won't match perfectly, due to the distortion the frame sees during bending, but I'll have to blend it after welding. Here are the pieces I cut with a jigsaw from a piece of 2.5" x 5" tubing:
To bend them, I designed a jig using AutoDesk's Fusion 360 software and had SendCutSend make the pieces. The jig uses the tab-and-slot design, similar to my weld/fab table show above. To bend the pieces, I'll use my oxy-acetylene torch with a rosebud tip. Here are the jig pieces laser cut:
Next, I welded the tab-and-slots, one layer at a time:
Stacking:
And complete:
The four holes in the jig match the 2" on center 5/8" holes of my weld/fab table so that I can anchor it to the table (these weld/fab tables are excellent!) I use these bushings with a screw to do so:
Here's the jig fastened to the table:
The slots in the end of the jig hold the pieces cut from the tubing, one on each side of the jig. Here's the bottom piece:
And the top piece:
I can't take photos while using the torch, but I heated each piece red hot and used C-clamps to form them to the curves of the jig, like this:
After cleaning them up, they turned out pretty good. Here's a bottom piece, ready for welding:
It's hard to see in that photo, but there's a 45° bevel on the bottom edge for welding the butt seam. This is as far as I got today. Stay tuned for the cutting of the frame pieces and welding.
OP
After working on the rear frame raise project, I decided to get the Savvy gas tank skid ready for the gas tank and install the tank in it. I started by cutting a radius on the steel pieces with a radius-cutting burr:
The burr does a good job of roughing-out the radius, but final sanding with a mini belt sanding makes it smooth:
With the steel pieces done, I moved on to the aluminum skid edges with the burr:
The cutter is made for steel, so to use it on aluminum, I had to stop frequently to cool it down, and use cutting wax. I finished up with the mini belt sander:
With the radiusing complete, I was confident the plastic tank won't be gouged during installation or use, so I fastened the steel pieces to the aluminum skid:
I think I got those pieces in the correct holes. Since I have a 1.25" body lift and I'm raising the rear frame, I have the front piece in the top holes and the rear piece in the bottom holes. If I screwed this up, somebody please tell me!
Finally, I installed the straps, inserted the tank, and tightened up the strap bolts:
Now, I just need to finish the rear frame raise to install this!
The burr does a good job of roughing-out the radius, but final sanding with a mini belt sanding makes it smooth:
With the steel pieces done, I moved on to the aluminum skid edges with the burr:
The cutter is made for steel, so to use it on aluminum, I had to stop frequently to cool it down, and use cutting wax. I finished up with the mini belt sander:
With the radiusing complete, I was confident the plastic tank won't be gouged during installation or use, so I fastened the steel pieces to the aluminum skid:
I think I got those pieces in the correct holes. Since I have a 1.25" body lift and I'm raising the rear frame, I have the front piece in the top holes and the rear piece in the bottom holes. If I screwed this up, somebody please tell me!
Finally, I installed the straps, inserted the tank, and tightened up the strap bolts:
Now, I just need to finish the rear frame raise to install this!