[bsevans]

I just wanted to share some photos of the FJ40 skid plate I just had fabricated here in Tucson. Except for one small triangular gusset it is made from one piece of 3/8" steel plate using a CNC precision plasma cutter. All the slots, holes and outer edges are smooth to the touch and need no secondary finish work. As you can see from the photo, I extended the skid plate back to fully protect the emergency brake.

[concretejungle]

Wow, that's tough looking. I am thinking of trying to make as much of a full belly skid as i can by the end of the summer.

[bandy rooster]

def. nice... looks like alot of thought and work went into it.



any pics of it on the rig?

[bsevans]

I forgot to post that this is a 78 FJ40 that after 15 years of rock crawling and general 4-wheeling has been restored. I've owned this beast for 20 years I have designed numerous modifications that are purely functional. I will post additonal threads for each item I have designed so others can use it if they so desire. I also should point out that the company that worked with me to fabricate this proto-type will build additional ones if you contact them. If anyone wants to call them, let me know and I will give you the engineer's name and phone number.

[bandy rooster]

you have to buy a star in order to post more pictures, best 20 bucks i ever spent that wasn't on anything ilegal... lol jk


email them to me at wheelsandwater@hotmail.com and i'll post them up for you for the time being.

[bandy rooster]

heres info on the silver start http://forum.ih8mud.com/40-55-series-tech/announcement-silver-star-supporters.html



but just send them to my email for now and i'll get ya going.

[awp_cruiser]

What does that thing weigh? Pretty cool.

awp

[bsevans]

80-85 pounds. You can high center the vehicle on the skid plate and it will not flex enough to touch either the transfer case or the transmission.

[bsevans]

Here is another photo that shows how the skid plate marries to the edge of the frame.

Contact information if your interested in purchasing one:
Caid Industries
Dave Watson
NEW NUMBER as of 01/31/07 - 520-889-7775
The prototype was under $400

[awp_cruiser]

I'd be afraid of bending one of those little allen heads over. One small rock and good luck getting a allen wrench in there and those are small enough that pliers won't be much help. You might want to look for some hardware that is a little more stout at the head.

It is going in my idea folder for later review....

[rusty_tlc]

Very stout looking.
What's the hose going into your t-case for?

[bandy rooster]

A common problem on pre 1988 Land Cruisers is the failure of the oil seal between the transmission and transfer case. When this occurs the transfer case tends to pump gear oil into the transmission, starving the transfer case of oil. it connects the two filler holes, so the transmission can return oil to the transfer case as needed.



or i could be way off... but i dunno... it seems like a goofy mod. wouldn't you just replace the seal?

[Mace]

Consider the difficults of splitting the tranny and tcase Vs installing a hose


BTW, you cut that statement from somewhere huh

[bandy rooster]

I'm starting not to like you mace.

[Mace]

[bsevans]

The allen head bolts you see are 12.9 rated. When and if I bend one over, I'll install the 10.9 hex heads I have in my shop. The "bent" allen heads can be removed with vice grips.
As far as the hose is concerened, I've had my seal go out 3 times over the course of 20 years. My experience as a mechanical engineer is that the hoses' primary purpose is to allow the pressure differential between the tranny and the transfer case that causes the fluid pumping past the bad seal to be minimized thus reducuing the amount of fluid being pumped and allowing for any fluid that is pumped into the tranny to drain back down and not eventually cause the tranny front seal to fail from over pressure due to eccessive fluid in the tranny. That hose is a steel braided -08 Parker Tough Cover with crimped fittings and adapters from McMaster-Carr. Far superior to the kits you can find at Specter Off Road or Man-A-Fre.
When I put the new Centerforce clutch in I will replace the seal. The hose will stay installed, as I believe that it will extend the life of the seal.

[4WD Toyota Owner Magazine]

That is one BURLY plate and very nicely done! Wow!

[Mace]

Originally Posted by bsevans

The allen head bolts you see are 12.9 rated. When and if I bend one over, I'll install the 10.9 hex heads I have in my shop. The "bent" allen heads can be removed with vice grips.
As far as the hose is concerened, I've had my seal go out 3 times over the course 20 years. My experience as a mechanical engineer is that the hoses' primary purpose is to allow the pressure differential between the tranny and the transfer case that causes the fluid pumping past the bad seal to be minimized thus reducuing the amount of fluid being pumped and allowing for any fluid that is pumped into the tranny to drain back down and not eventually cause the tranny front seal to fail from over pressure due to eccessive fluid in the tranny. That hose is a steel braided -08 Parker Tough Cover with crimped fittings and adapters from McMaster-Carr. Far superior to the kits you can find at Specter Off Road or Man-A-Fre.
When I put the new Centerforce clutch in I will replace the seal. The hose will stay installed, as I believe that it will extend the life of the seal.

You experience as a mechanical engineer should also tell you that if you have a pressure difference between the tranny and tcase you have an issue. They are both vented to the atmosphere....

I would check the vents next time you rebuild it..

And that is a Very nice plate..

[bsevans]

That is a very valid point. My intention is to convert the vent ports on both and run them to the vent canister on the upper firewall where I already have vent lines for both axles. I've already done this on the Australian transfer case I've rebuilt. I need to find the time to do the clutch job. You would think that when you retire you have all the time in the world – NOT SO! I’ve spent the last 4 months working on my turbo diesel 4x4.

[Mace]

Life has a nasty habit of not givig you enough time to do what you want, ever...


Enjoy retirement.. You deserve it!!

[4x4Poet]

Awesome!

How was the bending done? The corners are welded and grinded smooth?

80-85 lbs is a bit much. How would a 1/4 plate skid made in the same fashion hold up to belly strikes and crossover perching?

One nitpick. It seems from the photos that the front of the skid with the three crescent cut-outs is a little steep. Like it wouldn't foster slide overs. I think the sharp bend also makes me think that. In fact, is the skid plate lower than the OEM plate? Opinions?

EDIT: nevermind that last paragraph. The first pic answers all.

[bsevans]

The skid plate had to be slightly lower than the stock skid plate to accommodate the emergency brake clearance. As you can see from the photo, the emergency brake is exposed on the factory skid and for good reason. When crawling over rocks the gage of the factory skid flexes and presses against the transfer case allowing maximum exposure of the emergency brake drum. I’ve got two bent and distorted factory skids that are a testament to their flexibility. One of the purposes of this skid design is to completely protect the emergency brake with a skid that was as unyielding as possible. The inside depth of the skid is 2.75”, which is a clearance of ¼” between the drum and the skid plate. I’ve yet to get enough flex in the drive train to cause the drum to strike the skid. If I do, I will remove material from the inside of the skid directly below the drum. The reason I did not use ¼” plate was the fact that I wanted to maximize the stiffness. If you look at my factory skids, you will see that one of the main areas of permanent distortion is the transition zone from the skid plate to its two mounting flanges. This skid plate is not something the average fabrication shop can do. Cutting and bending 3/8” steel plate with an accuracy of 1/32” is not something you will find in your average machine shop. The CNC precision plasma cutter used to cut out all the features on the sheet leaves a smooth cut edge that is so smooth it requires no secondary grinding. Bending compound angles in 3/8” steel plate with precision requires a robust knife edge brake. There are welds at the three corners and a gusset is welded in at the other corner. There is no major grinding on the welds - only to remove the minor slag. The welds on the inside and outside of the skid are done by a certified welder. The angle between the front and side slopes of the skid and the ground are equal to or less than the factory skid. The bend radius used are equal to or larger than those used on the factory skid. The angle on the back of the skid except where the exhaust comes out gives a stiffness and departure angle the factory skid just does not have. Finally, yes there has been a minor loss of high center ground clearance, which I willingly gave up for piece of mind knowing I can hammer this skid on anything without concern for damage to the tranny, transfer or emergency brake. The loss of 5/8" of clearance won't stop me from taking the same line as I would have taken with the factory skid.

[4x4Poet]

Originally Posted by bsevans

...Cutting and bending 3/8” steel plate with an accuracy of 1/32” is not something you will find in your average machine shop. The CNC precision plasma cutter used to cut out all the features on the sheet leaves a smooth cut edge that is so smooth it requires no secondary grinding. Bending compound angles in 3/8” steel plate with precision requires a robust knife edge brake....

No doubt! It's an impressive feat compared to my little world of home fabbin'.

Finally, yes there has been a minor loss of high center ground clearance, which I willingly gave up for piece of mind knowing I can hammer this skid on anything without concern for damage to the tranny, transfer or emergency brake. The loss of 5/8" of clearance won't stop me from taking the same line as I would have taken with the factory skid.

Providing complete protection for the E-brake is a great design improvement. I like that while using stiff, 3/8" plate, you copied the OEM design shape and overall look, save the superior extention underneath the E-brake, but I wonder why the skid plate needs to extend below the frame to the left of the T-case instead of being flat with the frame except for a pocket around the T-case & E-brake?

Probably no matter, really. I think I'd go with that product since I have enough lift to make the slightly lower, flat belly of little consequence off-road.

Great effort and well thought out.

[bsevans]

The depth of the skid plate on the driver's side is similar to the factory skid plate which accommodates the PTO winch attachment. That is why there is a pocket formed in the factory skid and the third access hole to reach the PTO gear case. To do what you are talking about would entail far more labor, as there is a big difference in straight line bending on a brake versus forming a pocket for the transfer case by welding elements together or a very large hydraulic press. In either case, it would not work for me as my exhaust system needs the space that was provided by the factory skid - see photos. This skid is considerable stiffer than a flat plate due to the geometry of construction. I'm sure you understand the difference in stiffness between a flat plate and a piece of angle iron both of the same material thickness and width.

[bandy rooster]

all in all how long did it take you to design that?

[4x4Poet]

Originally Posted by bsevans

The depth of the skid plate on the driver's side is similar to the factory skid plate which accommodates the PTO winch attachment. That is why there is a pocket formed in the factory skid and the third access hole to reach the PTO gear case.
...This skid is considerable stiffer than a flat plate due to the geometry of construction. I'm sure you understand the difference in stiffness between a flat plate and a piece of angle iron both of the same material thickness and width.

I forgot about PTO clearance needs since I don't have one.

Thanks for all the detailed info. I appreciate it.

[Radd Cruisers]

Originally Posted by bsevans

The skid plate had to be slightly lower than the stock skid plate to accommodate the emergency brake clearance. As you can see from the photo, the emergency brake is exposed on the factory skid and for good reason. When crawling over rocks the gage of the factory skid flexes and presses against the transfer case allowing maximum exposure of the emergency brake drum. I’ve got two bent and distorted factory skids that are a testament to their flexibility. One of the purposes of this skid design is to completely protect the emergency brake with a skid that was as unyielding as possible. The inside depth of the skid is 2.75”, which is a clearance of ¼” between the drum and the skid plate. I’ve yet to get enough flex in the drive train to cause the drum to strike the skid. If I do, I will remove material from the inside of the skid directly below the drum. The reason I did not use ¼” plate was the fact that I wanted to maximize the stiffness. If you look at my factory skids, you will see that one of the main areas of permanent distortion is the transition zone from the skid plate to its two mounting flanges. This skid plate is not something the average fabrication shop can do. Cutting and bending 3/8” steel plate with an accuracy of 1/32” is not something you will find in your average machine shop. The CNC precision plasma cutter used to cut out all the features on the sheet leaves a smooth cut edge that is so smooth it requires no secondary grinding. Bending compound angles in 3/8” steel plate with precision requires a robust knife edge brake. There are welds at the three corners and a gusset is welded in at the other corner. There is no major grinding on the welds - only to remove the minor slag. The welds on the inside and outside of the skid are done by a certified welder. The angle between the front and side slopes of the skid and the ground are equal to or less than the factory skid. The bend radius used are equal to or larger than those used on the factory skid. The angle on the back of the skid except where the exhaust comes out gives a stiffness and departure angle the factory skid just does not have. Finally, yes there has been a minor loss of high center ground clearance, which I willingly gave up for piece of mind knowing I can hammer this skid on anything without concern for damage to the tranny, transfer or emergency brake. The loss of 5/8" of clearance won't stop me from taking the same line as I would have taken with the factory skid.

I am envious, although this skid plate might not be for everybody I really can appreciate the time it took to draw it up, cut it, bend it, weld it.......

Pretty much a piece of art which protects the cruisers under belly.

Some of the viewing audience has prolly been looking for such a skid plate at a good price.

Rob

[bsevans]

Well, that would be 18 years of thinking about what I wanted after seeing the damage upon returning home after playing on the rocks here in Arizona and three weeks of design time (including a mockup that went through two iterations) with the engineer at Caid Industries. Once he could find the window between some large jobs, he ran the plate through the CNC cutter and had it bent up and welded ready for pickup in less than a week.
I thought you might like to see what this skid plate is attached to.

[REZARF]

What a nice looking unit. Very Very beefy. Would another "run" of these skids be a bit more cost effective if we had a group run? Very nice piece. I would cross post in the 40 section as you may stir up a bit more buisness.

Rezarf <><

[rusty_tlc]

Would your engineer friend be interested in a slightly longer version for those of us with Toy Boxes?

Off Topic: What kind of dog is that in your rig?