21 replies to this topic

[Greg Kimble]

Back in December I was able to get a set of scales, I wanted to build a set of levelers with rolls offs that got the car up high enough to aid in making suspension adjustments.  This is what I came up with:

 

 

 

My materials list is loosely as follows:

 

40' of 2x2x3/16 angle steel (local steel supply company)

24 - 1/4" x 20 leveling feet (McMaster Carr)

24 - 1/4x20 6"threaded rods (McMaster Carr)

24 - 1/4x20 case hardened coupling nuts (McMaster Carr)

1 - 4' x 8' x 1/2" hardwood plywood (Lowes

3 - 8' 2"x4" (Lowes)

 

I made the roll off portions out of 1/2 plywood with a 2"x4" core which gave me the needed 2 1/2" height which equals the scale pad heights

 

Here is a picture showing the level of the scale pad and roll off.  The plywood is glued to the 2x4 core, the 2x4's are screwed together using 4" deck screws

 

 

To allow easy attachment of the cables, I cut a 1 1/4 OD hole using a hole saw to pass the cables through the frame 

 

 

I made small jigs to hold the coupling nuts in place while welding them to ensure that they were straight and consistent form point to point.

 

Here is a picture of two of the frames without the scale pad or roll off.  The corners were all coped and fit then mig welded. 

 

 

Any questions or comments are welcome

 

Greg

 

[Phil Mather]

I made very similar to you a few years ago.  I also used the 1/4" threaded rods.  If you can, upgrade to 1/2".  The 1/4" will bend very easily if side loaded.  1/2" will be much sturdier.  Use jackstands under the car if you stay with 1/4".

[RussMcB]

Maybe something like this:  http://www.wttool.co...egory_id/15975/

 

Or better (adjustable from above with an allen wrench):  https://www.acklands...m/CNECL1JFL.jpg

 

More options:  https://www.google.c...iw=1440&bih=791

[Greg Kimble]

Phil & Russ,

 

 

Thanks for the input, the legs will be the weak link, the swivel feet themselves have 500 lb capacity per foot.  The threaded rod is just normal threaded rod......my thought was if the standard rod couldnt take the side load, either replace them with a stainless steel rod, or shorten them/reinforce them with the longer threaded couplings. Those leveling feet are one of the main expenses in the project, if I remember correctly, the ones I am using were $3 something each, 1/2" are $8 something each.

 

Greg

[RussMcB]

Phil & Russ,

 

 

Thanks for the input, the legs will be the weak link, the swivel feet themselves have 500 lb capacity per foot.  The threaded rod is just normal threaded rod......my thought was if the standard rod couldnt take the side load, either replace them with a stainless steel rod, or shorten them/reinforce them with the longer threaded couplings. Those leveling feet are one of the main expenses in the project, if I remember correctly, the ones I am using were $3 something each, 1/2" are $8 something each.

 

Greg

I agree.  The cost for the industrial feet are high when you have to buy a lot of them.  I had to replace 2-3 in the used scale platform I bought a few years ago.

 

Make the leg lengths as short as possible.  :-)

[joeg5982]

Look exactly like the ones I made years ago!!

 

You need shorter threaded adjusters.  If your floor is screwed up to require that much adjustment (mine is) use blocks under the pads as necessary.  Target with a  laser to get all 4 pads level with each other.

[Bench Racer]

Great craftmanship.

 

A couple safety comments.

 

Add a lip to the front and rear of 1 or 2 platforms so the car can not roll off.

 

A less costly threaded adjuster are spherical headed carriage bolts of a larger diameter. Can be rotated using open end wrench on the square just under the head. You could add longer larger diameter threaded hex material to your frames (keeping your platform height) so that you could use carriage bolts that have full length thread. If you have the odd out of level location, for a couple bucks you can have different length carriage bolts.

[Jim Drago]

I agree on most above. the center legs make also make for a real pain in the ass leveling? I think one on each corner will be a lot easier? Or maybe full retract the middle legs, level the four corners and just bring down for support? Look nice though

Jim

[HoneyBadger - BrianW]

My recommendation is to bite the bullet and stick with the 1/2" legs. I changed out the legs on my pads to 8" from 4" and it's WAY easier to get under the car and make changes. With the 4" legs you can't get under the car sideways, which makes it very hard to adjust and/or break anything loose. With the 8" legs I can lay sideways and get better leverage on suspension bolts. I wouldn't want anything smaller than 1/2" with the car that high up in the air.

[dstevens]

Nice job.  I've been threatening to make some out of aluminum for a couple years now.   As for legs the Longacre units have six legs and I've used those and have been able to get them level without too much fuss.

 

For feet I use JW Winco in Wisconsin for some the things I've done including a welding/fab table that is pretty beefy. The local Grainger and Fastenal didn't have anything in stock near what I wanted.

 

http://www.jwwinco.c...leveling-mounts

[RacerX]

The length of the threaded rod looks scary, especially if you'll be wrenching under your Miata.  Consider increasing the thickness of the frame by flipping over another section of angle iron, attaching it to the bottom of the current angle iron, and attaching the threaded rod to this lower section. 

 

This additional angle iron will decrease the length of the "weak link" in your design, the threaded rod - at the very least if the rod bends due to an induced side motion, the additional frame will keep your Miata that much higher off the ground (which would be important if you're under it when this happens).  You can increase this structural height with box tubing between the existing top angle iron section and this proposed bottom angle iron section.

 

A clever person would increase the foot print of the bottom angle iron section, which during storage would cover the top portion of a set it is stacked upon.

 

I probably made this sound more complicated than it is, but if you're interested I can draw it up, scan it in, and throw a copy your direction.

 

Be safe, R1chy

[Phil Mather]

I was cheap too and actually used 1/2" carriage bolts.  The rounded head allowed them to rotate easily when unloaded for leveling.  I epoxied some fender washers to the garage floor and the carriage bolt heads were held in the center of the washer.  

[Greg Kimble]

Thanks for all of the kind comments and suggestions.  You all have suggested several safety items that I had not considered (adding a lip to keep the car from rolling off).  My floor is off by about 1 1/8" over the area where we will be doing our scaling.  The threaded rods shown in the pictures are 6" long, therefore I think they could be cut in half and still give enough adjustment to level all 4 pads and give a little clearance for getting to the cam bolts.  I think ideally moving to 1/2" hardware is the way to go, but on a more technical note, trying to avoid going to a larger size leg, how much more strength would a stainless steel Type 316 rod have over the standard rod being used?  Also, those of you using something similar levelers, how long are the legs on your units?  I like the idea mentioned above of being 8" for access.....maybe version 2 when we get some more down time.

 

Thanks

 

Greg  

[Randy Thieme]

...how much more strength would a stainless steel Type 316 rod have over the standard rod being used?

 

Not enough IMO.  Stainless is not necessarily stronger than other steels.  Without looking up the exact strengths my educated guess is SS might gain something over a Grade 2 threaded rod but what you'd really want is a Grade 5 or Grade 8 threaded rod.  As others have pointed out as long as everything's perfect (meaning a simple, vertical static load) those rods would support the weight.  The issue is what happens the moment there's a little side load.

[Glenn]

Not enough IMO.  Stainless is not necessarily stronger than other steels.  Without looking up the exact strengths my educated guess is SS might gain something over a Grade 2 threaded rod but what you'd really want is a Grade 5 or Grade 8 threaded rod.  As others have pointed out as long as everything's perfect (meaning a simple, vertical static load) those rods would support the weight.  The issue is what happens the moment there's a little side load.

Like when you jack the car up to get the scale pads out.......

[Keith Novak]

I would definitely either go to larger diameter rods or add some legs and shorten the adjustment part.  I did some rough calculations and it won't take a heck of a lot of side load to cause the legs to bend or fracture.

[dstevens]

Grade 8 threaded rod...

 

http://www.mcmaster....ed-rods/=lygylu

[Doug007]

It's not a matter of material strength but of the critical buckling length.  That is a function of elasticity and stainless has a lower modulus of elasticity than carbon steel.  So, while it is stronger, stainless will actually be MORE prone to buckling.  Once it's in a buckled shape, it's not going to hold up a miata.

 

Another key point is that the buckling load decreases with the square of the column length.

 

http://www.efunda.co...mns/columns.cfm

 

Short, stubby, and strong are the way to go.  Especially if you will be working under the car while it is supported by these things.

[Keith Novak]

It's not a matter of material strength but of the critical buckling length.  

I halfway agree.  I found the buckling load and it's not the critical load case.  Bending strength is much lower.  When you jack one side up, the rods will be loaded in bending as well as axially , more so on the outside legs.  That bending load will cause the rods to flex and once they flex (even prior to yield) it won't behave like a true Euler column.  You have a bad set of combined loading that won't be good with spindly legs.

[Ken Wilkinson]

Since I don't have the design, fabrication skills or equipment necessary to build my own, I went in with a buddy and purchased this set: http://www.ebay.com/...=item27d3764020 they are very sturdy, well made and do a great job.

But now I want to elevate them.  I have a 2 post lift and would like to be able to raise the car, place some type of stand under each corner that the leveling pad will sit on and then lower the car onto the pads and then be able to easily make adjustments from under the car.  I have used cinder blocks and they help but a fat boy like me on a creeper is still greater than 8 inches!  I would like to get the car up 2-3 feet.  The jack stands sold by Wheeler http://www.advanced-...2f4108d90a207ea are along the lines of what I would like to have.

Any suggestions?