-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
MASTER THREAD: Jack Points — location, use, damage, pads, etc.
- Thread starter Tam
- Start date
Dolemite
is my name
Nice solution - let us know how it works out. I'd be curious to know if the jack stand at maximum height can engage the jack, like you're suggesting. I'd guess that it's safe to do that since the main "rod" or whatever it's called on the jack is pretty beefy. Maybe someone with some experience w/ this can chime in.Hi, new M3P owner here in New England. I just read through this whole thread, which went in many different directions, but seems to have gotten back on-subject. I was surprised to learn that the jack points are aluminum and are part of the battery. That raises the question as to how, during the battery replacement, do they hold up the rest of the car?
I was impressed with the many different techniques discussed for jacking up the car. I have made adapters out of hockey pucks and rubber bumpers, which can be seen in the picture below. At left is my old 3.5 ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack cup as you slide it underneath.
A recurring concern, with just one jack point per corner, is safety while using floor jacks. While solutions exist, I am trying to work out a low-cost alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear. It will also work with one jack on one corner at a time. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving. The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most jacks, but I found some 2-ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see photo). These stands fit within the side rails of the old 3.5 ton jack and, in one orientation, in a new 2.5 ton Aluminum low-profile jack. To use them, jack up the car perhaps a bit higher than desired, then insert the small jack stand within the jack, then extending it as necessary to provide a back-up. Alternatively, a block of strong wood could be cut to fit the space under the jack.
I haven't actually used them yet and a few details, like how the top of the jack stands mate with the undersides of the jack without bending anything, need to be worked out. I just wanted to see if anyone is interested or has done this and how it worked out. I will post again after beta test.There is plenty of time now with COVID-19 lock down.
View attachment 540138
As for how they replace the battery - underneath the plastic rocker panel covers there are large holes on every corner. The technicians use a special adapter that fits into these holes to lift the car and then use the regular jack points on the battery to drop it out.
TonyJag
Member
TonyJag
Member
Thanks. I will let everyone know how it works out. Interesting..so there are more jack points hidden under the plastic cover.
jrweiss98020
Tessa's Tesla
TonyJag
Member
Sorry, I didn't mean to go silent, but have been busy working on this project. I jacked up the left front of my M3P using a hockey puck adaptor and made some measurements:
Condition. .....................Distance from plastic rocker cover to floor, as close to jack as possible
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely...............9.1"
LR tire down to small contact patch............11.6"
These heights are less that I expected and reveal that the cute little Walmart 2 Ton jack stands, the smallest I could find, are too tall and would need extensive modifications to work as envisioned. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism, to avoid bending anything. 2 or 4 ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive. So I went with wood and have completed one for the newer 2.5 Ton Aluminum floor jack. I hope to finish the older jack, which has a different saddle design, today, then will take pictures and post them on Flickr with a link and explanation here.
Condition. .....................Distance from plastic rocker cover to floor, as close to jack as possible
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely...............9.1"
LR tire down to small contact patch............11.6"
These heights are less that I expected and reveal that the cute little Walmart 2 Ton jack stands, the smallest I could find, are too tall and would need extensive modifications to work as envisioned. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism, to avoid bending anything. 2 or 4 ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive. So I went with wood and have completed one for the newer 2.5 Ton Aluminum floor jack. I hope to finish the older jack, which has a different saddle design, today, then will take pictures and post them on Flickr with a link and explanation here.
Last edited:
Dolemite
is my name
TonyJag
Member
Note: some of what I wrote in preceding posts is repeated here to make this a self-contained story of how a DIY owner can economically overcome the limitation of just one owner-accessible jack point per corner designed in the Model3 (and other models?) by Tesla. The normal DIY procedure of jacking up the car with a floor jack, then adding a conventional jack stand for safety, also typically found in floor jack instructions, is not approved.
While solutions exist to address this recurring safety concern, the goal here is to work out a low-cost, simple alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear, or to lift just the front or back axles. It will also work with one jack on one wheel. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving. While the idea could in theory be extended to all four corners, that would tie up 4 expensive floor jacks.
The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most big jacks, but I found some 2-Ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see Figure 1).These stands fit within the side rails of an old steel Larin 3.5 Ton jack and, in one orientation, in a new 2.5 Ton Aluminum low-profile “Racing” jack from Harbor Freight. To use them, one would jack up the car perhaps a bit higher than desired, then insert the small jack stand within the jack, then extend it as necessary to provide a back-up.
In order to explore feasibility of this concept, the left front of my new M3P was jacked up using a hockey puck adaptor and the following measurements made:
Condition......Distance from plastic rocker cover to floor, just ahead of jack.
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely..............9.1" (just 2.8“ rebound travel?)
LR tire down to small contact patch............11.6"
These heights are less than expected and reveal that the cute little Walmartian 2 Ton jack stands, the smallest evidently available for automotive use, are too tall and, in order to work as envisioned, would need extensive modifications that might weaken them and shrink the base. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism. 2 or 4 Ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive.
The use of construction lumber cut to fit the space under the jack was next in line, but is wood strong enough? From; Wood Strength
Compressive Strength (with grain) of Southern Yellow Pine (SYP) is 8,470 psi, stronger than most hardwoods and readily available Pressure Treated (PTSYP), used for fences, decks, etc. So a square inch of SYP could support 2 M3s! Other construction lumber is not far behind: Douglas fir at 7230 psi, Hemlock at 7200 psi , and Spruce at 5610 psi. So wood is strong enough, easily worked, and economical, so it can be sized at many times the needed capacity for our safety jack application. In fact, there are many stories on line about jack stands made of wood.
But it cannot be all one piece because it must be easily and quickly insertable without excessive elevation of the jack, while reaching under the car and relying mainly on feel. The scheme evolved to a Saddle Base Adaptor at the top, 3-4 inches tall, that spreads the force over the floor jack’s saddle base mechanism to avoid bending or over-stressing anything. The design and building of these Saddle Base Adaptors was the most challenging part of this project and verydependent on the jack design. Two very different designs resulted, one entirely made of wood and the other using wood and iron pipe.
NOTE to auto equipment manufacturers: This safety solution could be greatly simplified if jacks were designed with a load-bearing flat surface underneath their saddle base to begin with, avoiding the need for a complex custom Saddle Base Adaptor!
The bottom portion consists entirely of wooden blocks and is the same for both jacks and much easier to build.
The following tools were used:
· Band Saw
· Circular or Table or Radial Arm Saw
· Drill Press
· Belt Sander with coarse belt
· Files
· Hydraulic Press or Big Vise (to push the wooden dowel into the pipe)
· Calipers, Square, Rulers, Flat Feeler Gauge, Awl, etc.
· Extensive vocabulary of expletives.
The following paragraphs describe the designs.
Jack Point Adapters were made out of hockey pucks and rubber bumpers, which can be seen in Figure 1. At left is an old 3.5 Ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack saddle as you slide it underneath. The low profile jack goes down to ~3.4”.
Figure 2. is a bottom view of the new 2.5 Ton low profile Al "Racing" Jack. from Harbor Freight. Here in MA, they are open with COVID protection measures, but their 20% discount coupons don't work for floor jacks and other products listed in the fine print. But it was supposedly on sale.
The Saddle Base Adaptor for this jack, made from a scrap of 4x4 PTSYP, is shown in Figure 3. It was a challenge to make. Caliper measurements of the locations of the two 16mm pins were used to drill two 5/8” holes, then access slots cut with a band saw. But to get it to fit so the top just touched the bottom of the saddle base took hours of fiddly work with rat tail files and the band saw. Carbon paper and a thin feeler gauge were used to measure clearances.
Figure 4. shows it from a different angle, where you can see the ball detent intended to hold it place while rolling the jack under the car. It seems touchy, so will likely be replaced or supplemented with strong neodymium magnets.
Switching to the older non-low profile Larin 3.5 Ton jack, Figure 5. Is a bottom View. Note that the saddle base design is very different from the Aluminum Racing jack. There is no pin crossing through the center and the 30mm ID collar that receives the saddle pin is entirely accessible from below. The bottom of the steel saddle pin was squared and smoothed, thus appears shiny.
The main objective for design of the resulting Saddle Base Adaptor, shown in Figure 6, is that the force is shared between the saddle pin and its surrounding collar. It was made from a 1.25" pipe flange and pipe with a ~31 mm Diam. PTSYP dowel, made from 2x4 scrap, pressed in. The 1/8" x 1.25” roll pin was intended to hold it in place by twisting CCW (like Nikon Lenses), resting against a fortuitously-angled cross member. The aluminum disk at top is ~30mm in diameter and fits within the saddle collar, with thickness such that the load is balanced.
Figure 7. shows a bottom view of the Saddle Base Adaptor in place, with the end of the PTSYP dowel flush with the flange that will rest on a PTSYP block. The tip of the roll pin is visible above and resting upon the angled cross member. I may supplement that holding method with neodymium magnets.
In Figure 8., both Jacks are shown at ~ 11.5" height, enough to lift the left side front and (almost) rear tires off of the floor. At greater heights, minor refinements are needed. With the Larin jack at left, the upper blocks interfere with the lower bars of the jack, which is why the top 1” block is at an angle. That can easily be solved by notching some of the blocks. With the Aluminum Racing Jack at right, the aluminum cross piece between the upper bars begins to hit the Saddle Base Adaptor. So more fiddly work with the band saw, belt sander, and file could be done. But there is a trade off with weakening the Saddle Base Adaptor, so I will leave it alone until a need for greater height emerges.
In Figure 9., both Jacks are shown at ~ 9" height, enough to just lift left the front tire off the floor. Using combinations of 0 (as shown), 1" and 1.5" blocks, heights of 9, 10, 10.5, 11, 11.5, and with a little more work as mentioned above; 12, 12.5, 13, and 13.5 inches can be had. 0.5” is finer resolution than most jack stands and one could make even thinner blocks. The big bottom blocks were made from scraps of 4x6 PTSYP and are 3.5” high, but could also have been implemented by sticking together two- 1” and one 1.5” thick blocks., or some other combination of scrap lumber.
The whole kit appears in Figure10., in a former swimming pool bleach tablet bucket. Only the hockey puck lift point pads need to travel in the car.
USE INSRUCTIONS
Chock wheel(s) other that those you plan to work on. Insert the Saddle Base Adaptor(s) and lower the jack(s). Insert the Jack Point Adaptor(s), e.g. Hockey puck(s), into the jack point(s)under the rocker panel. Roll the Jack(s) under and center the hockey puck(s) in the Saddle(s). Jack up the car high enough to slide the big (3.5” tall) block into the jack. Jack up the car higher and insert thinner block(s) as needed. Lower the jack(s) so that both the safety back-up and the jack(s) themselves are loaded. Reverse this process to lower the car.
----------------
Please comment and especially let me know if you are going to try this with your jack(s). If you have the same jacks as mine, I could provide more details and dimensions.
I wrote this in Word and could provide that, with the 10 pictures pasted in, if anyone is interested.
I will actually need these jacks when my new Martian MW3 wheels arrive and will post how that works along with any refinements.
Do I need to mention any sort of disclaimer?
While solutions exist to address this recurring safety concern, the goal here is to work out a low-cost, simple alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear, or to lift just the front or back axles. It will also work with one jack on one wheel. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving. While the idea could in theory be extended to all four corners, that would tie up 4 expensive floor jacks.
The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most big jacks, but I found some 2-Ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see Figure 1).These stands fit within the side rails of an old steel Larin 3.5 Ton jack and, in one orientation, in a new 2.5 Ton Aluminum low-profile “Racing” jack from Harbor Freight. To use them, one would jack up the car perhaps a bit higher than desired, then insert the small jack stand within the jack, then extend it as necessary to provide a back-up.
In order to explore feasibility of this concept, the left front of my new M3P was jacked up using a hockey puck adaptor and the following measurements made:
Condition......Distance from plastic rocker cover to floor, just ahead of jack.
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely..............9.1" (just 2.8“ rebound travel?)
LR tire down to small contact patch............11.6"
These heights are less than expected and reveal that the cute little Walmartian 2 Ton jack stands, the smallest evidently available for automotive use, are too tall and, in order to work as envisioned, would need extensive modifications that might weaken them and shrink the base. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism. 2 or 4 Ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive.
The use of construction lumber cut to fit the space under the jack was next in line, but is wood strong enough? From; Wood Strength
Compressive Strength (with grain) of Southern Yellow Pine (SYP) is 8,470 psi, stronger than most hardwoods and readily available Pressure Treated (PTSYP), used for fences, decks, etc. So a square inch of SYP could support 2 M3s! Other construction lumber is not far behind: Douglas fir at 7230 psi, Hemlock at 7200 psi , and Spruce at 5610 psi. So wood is strong enough, easily worked, and economical, so it can be sized at many times the needed capacity for our safety jack application. In fact, there are many stories on line about jack stands made of wood.
But it cannot be all one piece because it must be easily and quickly insertable without excessive elevation of the jack, while reaching under the car and relying mainly on feel. The scheme evolved to a Saddle Base Adaptor at the top, 3-4 inches tall, that spreads the force over the floor jack’s saddle base mechanism to avoid bending or over-stressing anything. The design and building of these Saddle Base Adaptors was the most challenging part of this project and verydependent on the jack design. Two very different designs resulted, one entirely made of wood and the other using wood and iron pipe.
NOTE to auto equipment manufacturers: This safety solution could be greatly simplified if jacks were designed with a load-bearing flat surface underneath their saddle base to begin with, avoiding the need for a complex custom Saddle Base Adaptor!
The bottom portion consists entirely of wooden blocks and is the same for both jacks and much easier to build.
The following tools were used:
· Band Saw
· Circular or Table or Radial Arm Saw
· Drill Press
· Belt Sander with coarse belt
· Files
· Hydraulic Press or Big Vise (to push the wooden dowel into the pipe)
· Calipers, Square, Rulers, Flat Feeler Gauge, Awl, etc.
· Extensive vocabulary of expletives.
The following paragraphs describe the designs.
Jack Point Adapters were made out of hockey pucks and rubber bumpers, which can be seen in Figure 1. At left is an old 3.5 Ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack saddle as you slide it underneath. The low profile jack goes down to ~3.4”.
Figure 2. is a bottom view of the new 2.5 Ton low profile Al "Racing" Jack. from Harbor Freight. Here in MA, they are open with COVID protection measures, but their 20% discount coupons don't work for floor jacks and other products listed in the fine print. But it was supposedly on sale.
The Saddle Base Adaptor for this jack, made from a scrap of 4x4 PTSYP, is shown in Figure 3. It was a challenge to make. Caliper measurements of the locations of the two 16mm pins were used to drill two 5/8” holes, then access slots cut with a band saw. But to get it to fit so the top just touched the bottom of the saddle base took hours of fiddly work with rat tail files and the band saw. Carbon paper and a thin feeler gauge were used to measure clearances.
Figure 4. shows it from a different angle, where you can see the ball detent intended to hold it place while rolling the jack under the car. It seems touchy, so will likely be replaced or supplemented with strong neodymium magnets.
Switching to the older non-low profile Larin 3.5 Ton jack, Figure 5. Is a bottom View. Note that the saddle base design is very different from the Aluminum Racing jack. There is no pin crossing through the center and the 30mm ID collar that receives the saddle pin is entirely accessible from below. The bottom of the steel saddle pin was squared and smoothed, thus appears shiny.
The main objective for design of the resulting Saddle Base Adaptor, shown in Figure 6, is that the force is shared between the saddle pin and its surrounding collar. It was made from a 1.25" pipe flange and pipe with a ~31 mm Diam. PTSYP dowel, made from 2x4 scrap, pressed in. The 1/8" x 1.25” roll pin was intended to hold it in place by twisting CCW (like Nikon Lenses), resting against a fortuitously-angled cross member. The aluminum disk at top is ~30mm in diameter and fits within the saddle collar, with thickness such that the load is balanced.
Figure 7. shows a bottom view of the Saddle Base Adaptor in place, with the end of the PTSYP dowel flush with the flange that will rest on a PTSYP block. The tip of the roll pin is visible above and resting upon the angled cross member. I may supplement that holding method with neodymium magnets.
In Figure 8., both Jacks are shown at ~ 11.5" height, enough to lift the left side front and (almost) rear tires off of the floor. At greater heights, minor refinements are needed. With the Larin jack at left, the upper blocks interfere with the lower bars of the jack, which is why the top 1” block is at an angle. That can easily be solved by notching some of the blocks. With the Aluminum Racing Jack at right, the aluminum cross piece between the upper bars begins to hit the Saddle Base Adaptor. So more fiddly work with the band saw, belt sander, and file could be done. But there is a trade off with weakening the Saddle Base Adaptor, so I will leave it alone until a need for greater height emerges.
In Figure 9., both Jacks are shown at ~ 9" height, enough to just lift left the front tire off the floor. Using combinations of 0 (as shown), 1" and 1.5" blocks, heights of 9, 10, 10.5, 11, 11.5, and with a little more work as mentioned above; 12, 12.5, 13, and 13.5 inches can be had. 0.5” is finer resolution than most jack stands and one could make even thinner blocks. The big bottom blocks were made from scraps of 4x6 PTSYP and are 3.5” high, but could also have been implemented by sticking together two- 1” and one 1.5” thick blocks., or some other combination of scrap lumber.
The whole kit appears in Figure10., in a former swimming pool bleach tablet bucket. Only the hockey puck lift point pads need to travel in the car.
USE INSRUCTIONS
Chock wheel(s) other that those you plan to work on. Insert the Saddle Base Adaptor(s) and lower the jack(s). Insert the Jack Point Adaptor(s), e.g. Hockey puck(s), into the jack point(s)under the rocker panel. Roll the Jack(s) under and center the hockey puck(s) in the Saddle(s). Jack up the car high enough to slide the big (3.5” tall) block into the jack. Jack up the car higher and insert thinner block(s) as needed. Lower the jack(s) so that both the safety back-up and the jack(s) themselves are loaded. Reverse this process to lower the car.
----------------
Please comment and especially let me know if you are going to try this with your jack(s). If you have the same jacks as mine, I could provide more details and dimensions.
I wrote this in Word and could provide that, with the 10 pictures pasted in, if anyone is interested.
I will actually need these jacks when my new Martian MW3 wheels arrive and will post how that works along with any refinements.
Do I need to mention any sort of disclaimer?
HankLloydRight
No Roads
TonyJag
Member
Good points, but with COVID measures in place here, there is plenty of time now. I did mention that other solutions are available. Jackpoint was mentioned earlier in this thread. It is expensive and I didn't like the fixed height of 12", which is way more than you need to change wheels on an M3. Another solution mentioned earlier in this thread, Rennstand By Safe Jack, also was expensive, only goes down to 11.5", and is complicated to use, with slide pins.How much is your time and effort worth? Or your life for that matter
TonyJag
Member
SafeJax Story for TMC, Rev1, with pictures embedded.
Note: some of what I wrote in preceding posts is repeated here to make this a self-contained story of how a DIY owner can economically overcome the limitation of just one owner-accessible jack point per corner designed in the Model3 (and other models?) by Tesla. The normal DIY procedure of jacking up the car with a floor jack, then adding a conventional jack stand for safety, also typically found in floor jack instructions, is not approved.
While solutions exist to address this recurring safety concern, the goal here is to work out a low-cost, simple alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear, or to lift just the front or back axle. It will also work with one jack on one wheel. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving. While the idea could in theory be extended to all four corners, that would tie up 4 expensive floor jacks.
The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most big jacks, but I found some 2-Ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see Figure 1).
These stands fit within the side rails of an old steel Larin 3.5 Ton jack and, in one orientation, in a new 2.5 Ton Aluminum low-profile “Racing” jack from Harbor Freight, which I selected because it has almost 6” spacing between the side rails. Jacks with ~> 6” x 6” of clear spacing are best for this application because they allow for a base the size of small jack stands, yet have enough clearance so the jack can roll a bit as it lifts. The original concept of use as a safety mechanism was to jack up the car, perhaps a bit higher than desired, then insert the small jack stand within the jack, then extend it as necessary to provide a back-up.
Figure 1. First Try With 2-Ton WallMartian Jacks. Too Tall.
In order to explore feasibility of this concept, the left front of my new M3P was jacked up using a hockey puck adaptor and the following measurements made:
Condition......Distance from plastic rocker cover to floor, just ahead of jack.
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely..............9.1" (just 2.8“ rebound travel?)
LR tire down to small contact patch............11.6"
These heights are less than expected and reveal that the cute little WalMartian 2 Ton jack stands, the smallest evidently available for automotive use, are too tall and, in order to work as envisioned, would need extensive modifications that might weaken them and shrink the base. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism. 2 or 4 Ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive.
The use of construction lumber cut to fit the space under the jack was next in line, but is wood strong enough? From; Wood Strength
Compressive Strength (with grain) of Southern Yellow Pine (SYP) is 8,470 psi, stronger than most hardwoods and readily available Pressure Treated (PTSYP), used for fences, decks, etc. So a square inch of SYP could support 2 M3s! Other construction lumber is not far behind: Douglas fir at 7230 psi, Hemlock at 7200 psi , and Spruce at 5610 psi. So wood is strong enough, easily worked, and economical, so it can be sized at many times the needed capacity for our safety jack application. In fact, there are many stories on line about jack stands made of wood.
But it cannot be all one piece because it must be easily and quickly insertable without excessive elevation of the jack, while reaching under the car and relying mainly on feel. The scheme evolved to a Saddle Base Adaptor at the top, 3-4 inches tall, that spreads the force over the floor jack’s saddle base mechanism to avoid bending or over-stressing anything. The design and building of these Saddle Base Adaptors was the most challenging part of this project andverydependent on the jack design. Two different designs resulted, one entirely made of wood and the other using wood and iron pipe.
NOTE to auto equipment manufacturers: This safety solution could be greatly simplified if jacks were designed with a load-bearing flat surface underneath their saddle base to begin with, avoiding the need for a complex custom Saddle Base Adaptor!
The bottom portion consists entirely of wooden blocks and is the same for both jacks and much easier to build.
The following tools were used:
· Band Saw
· Circular or Table or Radial Arm Saw
· Drill Press
· Belt Sander with coarse belt
· Files
· Hydraulic Press or Big Vise (to push the wooden dowel into the pipe)
· Calipers, Square, Rulers, Flat Feeler Gauge, Awl, etc.
· Extensive vocabulary of expletives.
The following paragraphs describe the designs.
Jack Point Adapters were made out of hockey pucks and rubber bumpers, which can be seen inFigure 1. above. At left is an old 3.5 Ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack saddle as you slide it underneath. The low profile jack goes down to ~3.4”.
Figure 2. is a bottom view of the new 2.5 Ton low profile Al "Racing" Jack. from Harbor Freight. Here in MA, they are open with COVID protection measures, but their 20% discount coupons don't work for floor jacks and other products listed in the fine print. But it was on sale.
Figure 2. Bottom view of new 2.5 Ton Low-Profile Aluminum "Racing" Jack from Harbor Freight.
The Saddle Base Adaptor for this jack, made from a scrap of 4”x4” PTSYP, is shown in Figure 3. It was a challenge to make. Caliper measurements of the locations of the two 16mm pins were used to drill two 5/8” holes, then access slots cut with a band saw. But to get it to fit so the top just touched the bottom of the saddle base took hours of fiddly work with rat tail files and the band saw. Carbon paper and a thin feeler gauge were used to measure clearances.
Figure 3. Saddle Base Adaptor made from Southern Yellow Pine Pressure Treated (SYPPT) 4x4
Figure 4 .shows it from a different angle, where you can see the ball detent intended to hold it place while rolling the jack under the car. It seems touchy, so will likely be replaced or supplemented with strong neodymium magnets.
Figure 4. Saddle Base Adaptor Showing ball detent intended to hold it place. I will likely add magnets.
Switching to the older non-low profile Larin 3.5 Ton jack, Figure 5. Is a bottom View. Note that the saddle base design is very different from the Aluminum Racing jack. There is no pin crossing through the center and the 30mm ID collar that receives the saddle pin is entirely accessible from below. The bottom of the steel saddle pin was squared and smoothed, thus appears shiny.
Figure 5. Bottom View of Old Larin 3.5 Ton jack. Not low profile.
The main objective for design of the resulting Saddle Base Adaptor, shown in Figure 6., is that the force is shared between the saddle pin and its surrounding collar. It was made from a 1.25" pipe flange and pipe with a ~31 mm Diam. PTSYP dowel, made from 2x4 scrap, pressed in. The 1/8" x 1.25” roll pin was intended to hold it in place by twisting CCW (like Nikon Lenses), resting against a fortuitously-angled cross member. The aluminum disk at top is ~30mm in diameter and fits within the saddle collar, with thickness such that the load is balanced.
Figure 6. Saddle Base Adaptor made from 1.25" pipe flange and pipe with SYPPT pressed in. 1/8" roll pin was intended to hold it in place by twisting, I may add magnets.
Figure 7. shows a bottom view of the Saddle Base Adaptor in place, with the end of the PTSYP dowel flush with the flange that will rest on a PTSYP block. The tip of the roll pin is visible above and resting upon the angled cross member. I may supplement that holding method with neodymium magnets.
Figure 7. Bottom view of Saddle Base Adaptor in place. Tip of roll pin is visible above angled cross member
In Figure 8., both Jacks are shown at ~ 11.5" height, enough to lift the left side front and (almost) rear tires off of the floor. At greater heights, minor refinements are needed. With the Larin jack at left, the upper blocks interfere with the lower bars of the jack, which is why the top 1” block is at an angle. That can easily be solved by notching some of the blocks. With the Aluminum Racing Jack at right, the aluminum cross piece between the upper bars begins to hit the Saddle Base Adaptor. So more fiddly work with the band saw, belt sander, and file could be done. But there is a trade off with weakening the Saddle Base Adaptor, so I will leave it alone until a need for greater height emerges.
Figure 8.Jacks shown at ~ 11.5" height, enough to lift left side front and almost rear tires off floor. At greater heights, minor refinements are needed.
In Figure 9., both Jacks are shown at ~ 9" height, enough to just lift left the front tire off the floor. Using combinations of 0 (as shown), 1" and 1.5" blocks, heights of 9, 10, 10.5, 11, 11.5, and with a little more work as mentioned above; 12, 12.5, 13, and 13.5 inches can be had. 0.5” is finer resolution than most jack stands and one could make even thinner blocks. The big bottom blocks were made from scraps of 4x6 PTSYP and are 3.5” high, but could also have been implemented by sticking together two- 1” and one 1.5” thick blocks., or some other combination of scrap lumber.
Figure9. Jacks shown at ~ 9" height, enough to lift a front tire.
The whole kit appears in Figure10., in a former swimming pool bleach tablet bucket. Only the hockey puck lift point pads need to travel in the car.
Figure 10. The Whole Kit.
USE INSTRUCTIONS
Chock wheel(s) other that those you plan to work on. Insert the Saddle Base Adaptor(s) and lower the jack(s). Insert the Jack Point Adaptor(s), e.g. Hockey puck(s), into the jack point(s)under the rocker panel. Roll the Jack(s) under and center the hockey puck(s) in the Saddle(s). Jack up the car high enough to slide the big (3.5” tall) block into the jack. Jack up the car higher and insert thinner block(s) as needed. Lower the jack(s) so that both the safety back-up and the jack(s) themselves are loaded. Reverse this process to lower the car.
Please comment and especially let me know if you are going to try this with your jack(s). If you have the same jacks as mine, I could provide more details and dimensions.
I will actually need these jacks when my new Martian MW3 wheels arrive and will post how that works along with any refinements.
Note: some of what I wrote in preceding posts is repeated here to make this a self-contained story of how a DIY owner can economically overcome the limitation of just one owner-accessible jack point per corner designed in the Model3 (and other models?) by Tesla. The normal DIY procedure of jacking up the car with a floor jack, then adding a conventional jack stand for safety, also typically found in floor jack instructions, is not approved.
While solutions exist to address this recurring safety concern, the goal here is to work out a low-cost, simple alternative using 2 standard or low profile hydraulic floor jacks on one side of the car at a time, e.g. for rotating front<-->rear, or to lift just the front or back axle. It will also work with one jack on one wheel. I agree with those who have concluded that there should be no problem with tweaking the battery, which is repeatedly tolerated during normal driving. While the idea could in theory be extended to all four corners, that would tie up 4 expensive floor jacks.
The key idea is to leave the jacks in place and achieve safety by inserting something within the floor jack so it cannot collapse, even if hydraulic pressure is released for whatever reason. Most jack stands are too big for most big jacks, but I found some 2-Ton steel ones at Walmart for only $10 each that measure 5-5/8"x 6-1/4" at the base and extend from 10" to 15" in steps of ~3/4" (see Figure 1).
These stands fit within the side rails of an old steel Larin 3.5 Ton jack and, in one orientation, in a new 2.5 Ton Aluminum low-profile “Racing” jack from Harbor Freight, which I selected because it has almost 6” spacing between the side rails. Jacks with ~> 6” x 6” of clear spacing are best for this application because they allow for a base the size of small jack stands, yet have enough clearance so the jack can roll a bit as it lifts. The original concept of use as a safety mechanism was to jack up the car, perhaps a bit higher than desired, then insert the small jack stand within the jack, then extend it as necessary to provide a back-up.
Figure 1. First Try With 2-Ton WallMartian Jacks. Too Tall.
In order to explore feasibility of this concept, the left front of my new M3P was jacked up using a hockey puck adaptor and the following measurements made:
Condition......Distance from plastic rocker cover to floor, just ahead of jack.
Jack barely touching lift point.......................6.3"
LF tire just above floor; turns freely..............9.1" (just 2.8“ rebound travel?)
LR tire down to small contact patch............11.6"
These heights are less than expected and reveal that the cute little WalMartian 2 Ton jack stands, the smallest evidently available for automotive use, are too tall and, in order to work as envisioned, would need extensive modifications that might weaken them and shrink the base. There needs to be a few inches for an adaptor that spreads the force over the saddle base mechanism. 2 or 4 Ton Bottle jacks are also too tall, yet have a small base. "Shorty" bottle jacks might work, but they are heavy and expensive.
The use of construction lumber cut to fit the space under the jack was next in line, but is wood strong enough? From; Wood Strength
Compressive Strength (with grain) of Southern Yellow Pine (SYP) is 8,470 psi, stronger than most hardwoods and readily available Pressure Treated (PTSYP), used for fences, decks, etc. So a square inch of SYP could support 2 M3s! Other construction lumber is not far behind: Douglas fir at 7230 psi, Hemlock at 7200 psi , and Spruce at 5610 psi. So wood is strong enough, easily worked, and economical, so it can be sized at many times the needed capacity for our safety jack application. In fact, there are many stories on line about jack stands made of wood.
But it cannot be all one piece because it must be easily and quickly insertable without excessive elevation of the jack, while reaching under the car and relying mainly on feel. The scheme evolved to a Saddle Base Adaptor at the top, 3-4 inches tall, that spreads the force over the floor jack’s saddle base mechanism to avoid bending or over-stressing anything. The design and building of these Saddle Base Adaptors was the most challenging part of this project andverydependent on the jack design. Two different designs resulted, one entirely made of wood and the other using wood and iron pipe.
NOTE to auto equipment manufacturers: This safety solution could be greatly simplified if jacks were designed with a load-bearing flat surface underneath their saddle base to begin with, avoiding the need for a complex custom Saddle Base Adaptor!
The bottom portion consists entirely of wooden blocks and is the same for both jacks and much easier to build.
The following tools were used:
· Band Saw
· Circular or Table or Radial Arm Saw
· Drill Press
· Belt Sander with coarse belt
· Files
· Hydraulic Press or Big Vise (to push the wooden dowel into the pipe)
· Calipers, Square, Rulers, Flat Feeler Gauge, Awl, etc.
· Extensive vocabulary of expletives.
The following paragraphs describe the designs.
Jack Point Adapters were made out of hockey pucks and rubber bumpers, which can be seen inFigure 1. above. At left is an old 3.5 Ton non-low-profile jack, which goes down to 5" high. If you first plug the adaptor into the lift point, it just clears the highest point of the jack saddle as you slide it underneath. The low profile jack goes down to ~3.4”.
Figure 2. is a bottom view of the new 2.5 Ton low profile Al "Racing" Jack. from Harbor Freight. Here in MA, they are open with COVID protection measures, but their 20% discount coupons don't work for floor jacks and other products listed in the fine print. But it was on sale.
Figure 2. Bottom view of new 2.5 Ton Low-Profile Aluminum "Racing" Jack from Harbor Freight.
The Saddle Base Adaptor for this jack, made from a scrap of 4”x4” PTSYP, is shown in Figure 3. It was a challenge to make. Caliper measurements of the locations of the two 16mm pins were used to drill two 5/8” holes, then access slots cut with a band saw. But to get it to fit so the top just touched the bottom of the saddle base took hours of fiddly work with rat tail files and the band saw. Carbon paper and a thin feeler gauge were used to measure clearances.
Figure 3. Saddle Base Adaptor made from Southern Yellow Pine Pressure Treated (SYPPT) 4x4
Figure 4 .shows it from a different angle, where you can see the ball detent intended to hold it place while rolling the jack under the car. It seems touchy, so will likely be replaced or supplemented with strong neodymium magnets.
Figure 4. Saddle Base Adaptor Showing ball detent intended to hold it place. I will likely add magnets.
Switching to the older non-low profile Larin 3.5 Ton jack, Figure 5. Is a bottom View. Note that the saddle base design is very different from the Aluminum Racing jack. There is no pin crossing through the center and the 30mm ID collar that receives the saddle pin is entirely accessible from below. The bottom of the steel saddle pin was squared and smoothed, thus appears shiny.
Figure 5. Bottom View of Old Larin 3.5 Ton jack. Not low profile.
The main objective for design of the resulting Saddle Base Adaptor, shown in Figure 6., is that the force is shared between the saddle pin and its surrounding collar. It was made from a 1.25" pipe flange and pipe with a ~31 mm Diam. PTSYP dowel, made from 2x4 scrap, pressed in. The 1/8" x 1.25” roll pin was intended to hold it in place by twisting CCW (like Nikon Lenses), resting against a fortuitously-angled cross member. The aluminum disk at top is ~30mm in diameter and fits within the saddle collar, with thickness such that the load is balanced.
Figure 6. Saddle Base Adaptor made from 1.25" pipe flange and pipe with SYPPT pressed in. 1/8" roll pin was intended to hold it in place by twisting, I may add magnets.
Figure 7. shows a bottom view of the Saddle Base Adaptor in place, with the end of the PTSYP dowel flush with the flange that will rest on a PTSYP block. The tip of the roll pin is visible above and resting upon the angled cross member. I may supplement that holding method with neodymium magnets.
Figure 7. Bottom view of Saddle Base Adaptor in place. Tip of roll pin is visible above angled cross member
In Figure 8., both Jacks are shown at ~ 11.5" height, enough to lift the left side front and (almost) rear tires off of the floor. At greater heights, minor refinements are needed. With the Larin jack at left, the upper blocks interfere with the lower bars of the jack, which is why the top 1” block is at an angle. That can easily be solved by notching some of the blocks. With the Aluminum Racing Jack at right, the aluminum cross piece between the upper bars begins to hit the Saddle Base Adaptor. So more fiddly work with the band saw, belt sander, and file could be done. But there is a trade off with weakening the Saddle Base Adaptor, so I will leave it alone until a need for greater height emerges.
Figure 8.Jacks shown at ~ 11.5" height, enough to lift left side front and almost rear tires off floor. At greater heights, minor refinements are needed.
In Figure 9., both Jacks are shown at ~ 9" height, enough to just lift left the front tire off the floor. Using combinations of 0 (as shown), 1" and 1.5" blocks, heights of 9, 10, 10.5, 11, 11.5, and with a little more work as mentioned above; 12, 12.5, 13, and 13.5 inches can be had. 0.5” is finer resolution than most jack stands and one could make even thinner blocks. The big bottom blocks were made from scraps of 4x6 PTSYP and are 3.5” high, but could also have been implemented by sticking together two- 1” and one 1.5” thick blocks., or some other combination of scrap lumber.
Figure9. Jacks shown at ~ 9" height, enough to lift a front tire.
The whole kit appears in Figure10., in a former swimming pool bleach tablet bucket. Only the hockey puck lift point pads need to travel in the car.
Figure 10. The Whole Kit.
USE INSTRUCTIONS
Chock wheel(s) other that those you plan to work on. Insert the Saddle Base Adaptor(s) and lower the jack(s). Insert the Jack Point Adaptor(s), e.g. Hockey puck(s), into the jack point(s)under the rocker panel. Roll the Jack(s) under and center the hockey puck(s) in the Saddle(s). Jack up the car high enough to slide the big (3.5” tall) block into the jack. Jack up the car higher and insert thinner block(s) as needed. Lower the jack(s) so that both the safety back-up and the jack(s) themselves are loaded. Reverse this process to lower the car.
Please comment and especially let me know if you are going to try this with your jack(s). If you have the same jacks as mine, I could provide more details and dimensions.
I will actually need these jacks when my new Martian MW3 wheels arrive and will post how that works along with any refinements.
Last edited:
My car was lowered with KW, with suitable height setting without scrapping (P+ height), I am not able to use the jack pads with lowered jack. Maybe 1/4" under the car.
I need to order some thin jack pads from China without any metal substance inside to clear the way.
I need to order some thin jack pads from China without any metal substance inside to clear the way.
To be fair, you don't need jack pads as has been said before. But since I'm using Jackpoint jack stands, like you I need the extra clearance.
I just use 2 jacks. I got this one, which is only 2.75" tall when lowered, and nice and small so it's easy to maneuver:
https://smile.amazon.com/gp/product/B00OCIBPIM
I use it to lift the car enough to fit my jack with Jackpoint adapter plate at the other jack point.
I just use 2 jacks. I got this one, which is only 2.75" tall when lowered, and nice and small so it's easy to maneuver:
https://smile.amazon.com/gp/product/B00OCIBPIM
I use it to lift the car enough to fit my jack with Jackpoint adapter plate at the other jack point.
TonyJag
Member
Interesting jack. As you noted, it is extremely low profile. It also has a safety pin to eliminate the need for a jack stand, but that only works when fully extended to 15".
You have to buy them if you want them. (And Tesla doesn't sell them.)
Similar threads
