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Troy
01-13-2020, 03:21 PM
Hey All,

I searched for Cribbing that people made to support their Tri-Five. I'm looking for Photo's and/or designs of cribs to both support car under the four wheels and also to support the body above the frame when separated. Anybody got anything? Thanks!!!

55 Rescue Dog
01-13-2020, 04:15 PM
I had to crib the body and my frame a lot trying to get it on and off a trailer, and on to a frame. For the most part I used two 9 foot 4x4's, and 16 concrete blocks, which are pretty cheap, and useful for other stuff. I even used them as a jig for a big table welding project.
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Gmvette
01-14-2020, 07:42 AM
I lifted the body under my 4 post lift with straps. Measured the frame as lifted and faded up with scrap tubing (all different sizes) to support the body at most of the same mounting points. Bolted it down. It rolls around on heavy 5” casters. Did all the body work and paint on the dolly. After complete and body back on the frame cashed in the steel dolly (all cut up) for scrap.

if one has a convertible more bracing may be necessary.

BamaNomad
01-14-2020, 08:06 AM
I had to crib the body and my frame a lot trying to get it on and off a trailer, and on to a frame. For the most part I used two 9 foot 4x4's, and 16 concrete blocks, which are pretty cheap, and useful for other stuff. I even used them as a jig for a big table welding project.
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RD, I too use cinder blocks as you did when I need to block up a car 'in position', BUT... before I put a cross-tie on the block and load it, I cut a 16" length of 2x8 to place on the top of each stack of cinder blocks to ensure the load is distributed across the entire block-top surface... and make sure your blocks are evenly stacked... :)

Gmvette
01-15-2020, 06:59 AM
A heavy duty cherry picker will lift the whole body no problem. I used it plenty of times before I got the 4 post lift. Just fab your self a method to suspend the straps or chain which ever you have access to. The small lift jack with blocks and 4x4 scares the b-Jesus out of me. Not mobile to move it around.

A body cradle can be fabricated from wood available at Lowes or Home Depot on the cheap. Casters too. Body bolted to it would be so secure. Also it would make it so much easier to work on. This would also allow you to put the body/car on a real car trailer vs the wagon type for mobility.

BamaNomad
01-15-2020, 08:22 AM
That's a good point, gmvette... the stationary blocked up body is certainly NOT mobile! :) I've only used stationary blocking to a body high enough to remove from the original frame, mounting/unmounting to/from a rotisserie, and reinstallation onto a frame... and I did all that before I had a lift and I did it all by myself using a floor jack! So one's methods are limited by their tools and resources~!

chevynut
01-15-2020, 10:18 AM
I use two cherry pickers to move the bodies off and on the frame. One in the rear, one in the front similar to what RD showed. However, since I don't have hood hinge holes in my firewall I've been using the cowl body mounts to attach a chain to. I've done the same thing on the HEMI55. That said, if all you want to do is hold the body off the frame and roll/slide the frame out, blocking it up works fine.

I don't even know what "cribbing" is and have never heard the word used. :confused:

Rick_L
01-15-2020, 10:38 AM
I don't even know what "cribbing" is and have never heard the word used.

What you see here is an example. Basically it is temporarily stabilizing/supporting a large or heavy object after you lift it or prepare to move it.

The concrete blocks are a poor way to support a load. They are very poor in compression load capacity. In this example they don't have enough footprint to have decent lateral stability either.

55 Rescue Dog
01-15-2020, 10:48 AM
I wouldn't crawl under it, but for what I was doing the blocks were plenty strong and stable for what I was doing. I gave it a shake test every step of the way, and each block is holding up less that 300lbs per corner, not a whole building, or a complete car. The only scary part was rolling the chassis under it up that high on blocks, but I was careful. Didn't really have a better option for the moment, but it worked fine.

chevynut
01-15-2020, 11:15 AM
The concrete blocks are a poor way to support a load. They are very poor in compression load capacity. In this example they don't have enough footprint to have decent lateral stability either.

They only hold up houses and large commercial buildings, so it's possible they can't support a car body that might weigh 800 pounds. :eek:

"As per standards published in 2003 by ASTM, an international building standards non-profit, all concrete blocks must support at least 1,700 pounds of weight per square inch (PSI). This standard only describes minimum requirements, however."

I don't see how lateral stability is any worse than 4 jackstands. I wouldn't hesitate to use CONCRETE blocks (not cinder blocks) to support a body. They need to be used with the holes vertically oriented for strength. I'd even work under the car supported that way. No worse than jackstands.

Troy
01-15-2020, 11:49 AM
Hello all, my main need was to lift the car off the floor high enough to fit myself under the car and support it under all four wheels like reality. I need to make measurements like trans output angle, differential angle to make sure they are in the correct phase to eliminate or reduce vibrations. My dad built my trans cross member years ago and I don't know how he got the location. I'm installing new engine mounts and trans mount and I want it right. I also want to do work under the car prior to dropping the frame out. By the word cribbing, it's what our rigging team at work use to support things they lift and need to support https://en.wikipedia.org/wiki/Box_crib. I'm just going to make some 12" x 12" x 12" cubes out of either 2 x 4's or 4 x 4's

chevynut
01-15-2020, 11:57 AM
The stock engine angle is 4 degrees down in the rear relative the the main frame rails. If you don't have a digital level, just level the frame and measure the engine angle. The pinion should point up to the front at the same angle, under load.

55 Rescue Dog
01-15-2020, 02:26 PM
I'm finding my new car dollies work great for lining up body mounts, and moving it bits at a time, with the weight of the body supported barely off the frame. For a lot of other stuff I like to have the weight of the car sitting on the tires. The dollies get the car up just high enough you can slide under it. I did see a picture of a guy that made some 2x4 cribbing to fit on top of the wheel skates to get the car up a little higher. Of course they are also great for spinning your car around in the garage.
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Troy
01-15-2020, 03:28 PM
The stock engine angle is 4 degrees down in the rear relative the the main frame rails. If you don't have a digital level, just level the frame and measure the engine angle. The pinion should point up to the front at the same angle, under load.

CN I know that angle, but I don't know if my dad did so I want to check it as well as install the new engine and trans mounts. It's going to be hard to measure the pinion angle maybe I can tie my kid under the car!!!:D. I was told the pinion should be ~1/2 deg down at rest. How does that sound to all. One other thing is there's a lot of work to do under the car before it's separated that's why I want the cribbing.

Rick_L
01-15-2020, 03:59 PM
"As per standards published in 2003 by ASTM, an international building standards non-profit, all concrete blocks must support at least 1,700 pounds of weight per square inch (PSI). This standard only describes minimum requirements, however."

I don't see how lateral stability is any worse than 4 jackstands. I wouldn't hesitate to use CONCRETE blocks (not cinder blocks) to support a body. They need to be used with the holes vertically oriented for strength. I'd even work under the car supported that way. No worse than jackstands.

I was under the perhaps misguided (or perhaps not) impression that a concrete block and a cinder block are the same thing. I found that for the most part they are not. Cinder blocks are made from cement and fly ash. Concrete blocks are made from concrete - however the concrete composition can contain fly ash. And yes there's an ASTM spec for concrete blocks, but are all "concrete blocks" made to ASTM standards? I really doubt it. I did find a comment by a civil engineer saying that you should consider them the same unless it's known otherwise.

RD's stack of blocks is about 3' to 3-1/2' high. A decent jack stand that tall is going to have a much bigger footprint than a concrete block. Looks like it would only take 10-20 pounds of side force to knock RD's stack over.

When I was young and dumb and broke I used concrete/cinder blocks to support a car for months in my dad's garage. I worked under it a bunch. One day I was out there working on it, not underneath - barely touched the car and one of the blocks cracked and collapsed. I learned my lesson and thanked God I wasn't under the car. Of course they could have been "cinder blocks".

55 Rescue Dog
01-15-2020, 04:01 PM
CN I know that angle, but I don't know if my dad did so I want to check it as well as install the new engine and trans mounts. It's going to be hard to measure the pinion angle maybe I can tie my kid under the car!!!:D. I was told the pinion should be ~1/2 deg down at rest. How does that sound to all. One other thing is there's a lot of work to do under the car before it's separated that's why I want the cribbing.
I'm not exactly sure, but I think what I was suggesting would work with car skates. It allows you to have the car sitting on the suspension, without being bound up so you can get measurements, and still have room to get under it.

chevynut
01-15-2020, 04:13 PM
CN I know that angle, but I don't know if my dad did so I want to check it as well as install the new engine and trans mounts. It's going to be hard to measure the pinion angle maybe I can tie my kid under the car!!!:D. I was told the pinion should be ~1/2 deg down at rest. How does that sound to all. One other thing is there's a lot of work to do under the car before it's separated that's why I want the cribbing.

So why don't you wait til the frame is out from under the car to set up the engine/tranny and the rearend? I'm not understanding why you want to do it while the frame is under the car. If you don't have any suspension control device in the rear like traction bars, 4-link, or something like that I think you need more than 1/2 degree for axle wrap. Not sure how much though. I don't have to worry about it with the C4 IRS. :)

55 Rescue Dog
01-15-2020, 04:42 PM
Not exactly off subject, but I've been waiting to see CN's finished body on the finished frame, and how he did it. What's the hold up? I would be scared too. It's much easier with an empty shell. Looked easy on the 1955 assembly line.