DIY alignment equipment
#21
Now that I am not trying to post from my phone (It refreshes the page any time I try to upload a picture...)
This is my set up. Made from 2x10 and 2x12, along with decking screws, some hard board and grease for slip plates/leveling, pvc pipe, string, tape measure, and a Racer Parts Wholesale caster/camber gauge. Whole thing ended up being about $120 to set up.
This is my set up. Made from 2x10 and 2x12, along with decking screws, some hard board and grease for slip plates/leveling, pvc pipe, string, tape measure, and a Racer Parts Wholesale caster/camber gauge. Whole thing ended up being about $120 to set up.
#22
I have the SmartStrings rig that is similar to the PVC arrangement x_25 fabricated. It works pretty well but it takes about 5x time to set it up as it does to do the alignment adjustments. I did my own alignment had it checked my an actual expert and I was spot on.
Toe plates work nicely for minor adjustments but you have to be very careful to make the exact adjustments on both sides to avoid getting things off center thereby goofing up the thrust angle. That is the advantage of the string method. You do the alignment based on the true center of the car, assuming you get the strings right ;-)
The various camber gauges all work on the same principal and seem to work well as long as they reference the rim and not the tire.
I've been doing homebrew alignments on a C4 Corvette for the last few years. With the clamshell hood, I was able to access all the alignment adjusters with the car on the ground. With the Miata, I will need to fab some stands.
Toe plates work nicely for minor adjustments but you have to be very careful to make the exact adjustments on both sides to avoid getting things off center thereby goofing up the thrust angle. That is the advantage of the string method. You do the alignment based on the true center of the car, assuming you get the strings right ;-)
The various camber gauges all work on the same principal and seem to work well as long as they reference the rim and not the tire.
I've been doing homebrew alignments on a C4 Corvette for the last few years. With the clamshell hood, I was able to access all the alignment adjusters with the car on the ground. With the Miata, I will need to fab some stands.
#23
How do you make adjustments to get your car level? I want to get into doing my own alignments, but my garage floor slopes to a drain in the center, making leveling the car difficult. I like Hamerly's setup, but I don't have a welder. (or very much fabrication skill for that matter)
Now that I am not trying to post from my phone (It refreshes the page any time I try to upload a picture...)
This is my set up. Made from 2x10 and 2x12, along with decking screws, some hard board and grease for slip plates/leveling, pvc pipe, string, tape measure, and a Racer Parts Wholesale caster/camber gauge. Whole thing ended up being about $120 to set up.
This is my set up. Made from 2x10 and 2x12, along with decking screws, some hard board and grease for slip plates/leveling, pvc pipe, string, tape measure, and a Racer Parts Wholesale caster/camber gauge. Whole thing ended up being about $120 to set up.
#26
How do you make adjustments to get your car level? I want to get into doing my own alignments, but my garage floor slopes to a drain in the center, making leveling the car difficult. I like Hamerly's setup, but I don't have a welder. (or very much fabrication skill for that matter)
#27
this is a repost of an old thread I tried to start last fall. I was playing around with DIY alignments, and found an interesting shortcut:
I’ve been playing around with my alignment lately. As anyone who has fiddled with their alignment knows, you can use the Pythagorean theorem to calculate your toe or camber pretty easily by comparing your wheel to a straight reference. I’ve been using the string method and a carpenter's square as my references. I found it annoying to have to calculate the angle every time I made measurements, and it got me thinking: what is the optimal hypotenuse length (e.g., the diameter of your wheel, or length of your alignment stick) to get a 10:1 ratio between changes in distance between your reference & wheel, and changes to your alignment in degrees? It turns out the optimal length for an alignment stick is just about exactly 573mm, or 22 9/16”. With an alignment stick this length, you can move the top of your stick inboard 1mm from the reference, and it will lower your camber by .1°. Here’s where it gets funky: the OD’s of our more common wheel/tire combos are very close to this number:
195/50/15 on 15x7’s = 576mm
205/50/15 on 15x8 = 586mm
225/45/15 on 15x9 = 583mm
All three of these will get you within a gnat’s *** of .1° change in alignment for every 1mm of movement at the outside edge of the tire. Now obviously this doesn’t take into consideration sidewall deflection, tire inflation, tire wear, or any number of other factors.
I don’t know if this is common knowledge, but I thought it was worth sharing.
I’ve been playing around with my alignment lately. As anyone who has fiddled with their alignment knows, you can use the Pythagorean theorem to calculate your toe or camber pretty easily by comparing your wheel to a straight reference. I’ve been using the string method and a carpenter's square as my references. I found it annoying to have to calculate the angle every time I made measurements, and it got me thinking: what is the optimal hypotenuse length (e.g., the diameter of your wheel, or length of your alignment stick) to get a 10:1 ratio between changes in distance between your reference & wheel, and changes to your alignment in degrees? It turns out the optimal length for an alignment stick is just about exactly 573mm, or 22 9/16”. With an alignment stick this length, you can move the top of your stick inboard 1mm from the reference, and it will lower your camber by .1°. Here’s where it gets funky: the OD’s of our more common wheel/tire combos are very close to this number:
195/50/15 on 15x7’s = 576mm
205/50/15 on 15x8 = 586mm
225/45/15 on 15x9 = 583mm
All three of these will get you within a gnat’s *** of .1° change in alignment for every 1mm of movement at the outside edge of the tire. Now obviously this doesn’t take into consideration sidewall deflection, tire inflation, tire wear, or any number of other factors.
I don’t know if this is common knowledge, but I thought it was worth sharing.
#29
How do you make adjustments to get your car level? I want to get into doing my own alignments, but my garage floor slopes to a drain in the center, making leveling the car difficult. I like Hamerly's setup, but I don't have a welder. (or very much fabrication skill for that matter)