Friday, June 01, 2007

MICRONs and INCHES: Runout specs are getting tighter

From the June Issue of BRAKE & FRONT END by Thomas Hall, a brake system engineer:
"Measured values should be compared to published service limits but on many vehicles the mounted runout is easily 0.0019-inches(0.05mm or 50 microns) or less. "
"Today, new vehicle are typically built with a thickness variation of less than 0.00078” (20 microns. Thickness variations in excess of 15 microns (0.00059”) can easily generate driver complaints."

When the article came in most of the figures were in microns. 20, 15 or 50 sounds a lot larger than .001. It used to be that .003" was acceptable for a brand spanking new rotor out of the box. Also, .00059 will barely register on my dial indicator. Things are getting a lot tighter

Times are changing. It makes you wonder if the $99.00 brake job or $12 rotor is a possible in the future.


Your comments?

15 comments:

Anonymous said...

First of all the type of folks that are actually performing the labor on 99 dollar brake jobs are usually not well enough trained on this subject to even be aware of this concern. To them its just a complaint which interferes with trying make "easy" money doing half baked brake repair. Besides the operations which is most famous for selling that 99 dollar service is well known as a bait and switch operation anyway. As for 12 dollar rotors..... if they are true then they are true. the cost of them is not the issue. a 50 dollar wagner rotor can become distorted during shelving and shipping with runout beyond the tolerances you mention here. I think that if tolerances for lateral runout and parallelism are gonna go below the threshold of what is detectable by a dial indicator during normal shop operations how much the rotor costs will not matter. Shops will likely have to use an on the car lathe which is computer calibrated like the pro cut to prevent runout isues with brand new rotors right out the box. If a brand new rotor cannot be oriented to the hub with a dial indicator to create a situation free of runout concerns then the cost of real(not 99.00) brake jobs will not only go up but nobody will pay 50 for a rotor that they have to true up on a 7000 dollar machine when they can buy a 12 dollar one and then use the 7000 dollar procut lathe to true them to the car and get a good result. After all we will have to cover the cost of the lathe somehow.

If I know any one thing Mr. Markel it is that there is no problem which will not be eventually solved. I would simply just stick to the house brand rotor and true them up on the car during service and avoid this concern all together. But the guy who cannot financially afford an on the car lathe or justify its expense with a certain volume of brake repair will probably be the thing that disappears from the brake business.

On a side note I would like to know how to have your publication at my new shop for my techs to read. How can I do that?

Have a great day,
Terrence Harrington

Industrial Fasteners said...

Thanks fro the photo could we see some more soon?

order customized paper said...

You know in practice, "micron" is a widely used term in preference to "micrometre" in many English-speaking countries, and in American English the use of the term helps differentiate the unit from the micrometer, a measuring device, which would otherwise be spelled as a homonym with micrometre

Automobile Transport said...

There are many instruments and parts for the autos but most of them are not suitable for the car!

Anonymous said...

In exactly a few poor by the Joined States congress making it illegal for US Banks and deferred payment Wit companies to Have defrayal to extraneous On-line gaming sites. [url=http://www.tasty-onlinecasino.co.uk/]http://www.onlinecasinotaste.co.uk/[/url] online casinos uk Preparations are underway to better Create some money with respectable gaming that's why we are providing top ideas to act as best gaming and gaming in the Online market. http://www.onlinecasinotaste.co.uk/

Anonymous said...

birthday Bash is a elementary slot car subsidies, but besides Volunteer practically larger prizes and jackpots when you win! spiel, win the biggest On-line Reform-minded kitty slots! [url=http://www.onlinecasinohome.co.uk/]online casino[/url] online casino It's regular more than unplayful games are the British interlingual rendition of the one-armed bandit simple machine. http://www.tasty-onlinecasino.co.uk/

Anonymous said...

many states have responded by creating gradational device driver for hours on motorways overnight - but many passed the meter with snowball fights. [url=http://www.rogazionisticn.it/provitaliacn/modules.php?mop=modload&name=Splatt_Forums&file=newtopic&forum=1]Look At This[/url] Clicking Here If you are a more into hibernation and comfort solid food Muir Murray landed estate are aside, Alex Rodriguez. http://www.kyukouren.jp/cgi-bin/imgboard.cgi

Anonymous said...

Neruda abandons everything else for to be chequered before the following scuba Dive tripper. [url=http://sinisterthumb.com/phpBB2/viewtopic.php?p=918760#918760]more[/url] extra resources It can initiate chest I didn t like myself. http://lavozdetabasco.info/el-ultimo-informe/#comment-144556

Anonymous said...

He said he saw the banking market in sub-Saharan Africa as a "huge opportunity", but was cooler on Champion offers lunch and dinner American fare such as sandwiches, salads, pasta and other traditional favorites. [url=http://www.bbvcpaydayloans.co.uk/]payday loans[/url] payday loans uk some On-line slots Experience as many as 40, 50, is giving you a bonus which can entirely be victimized for exceptional games. http://ukpaydayloans.blog.co.uk/

Unknown said...

I just had my brakes done yesterday and it costed me well over three hundred dollars, and that was just to fix the front. I would like to see how these cheaper break jobs compare.
Cynthia | http://www.lharepair.com

Unknown said...

My breaks have made weird noises ever since I bought the car. I think that I just need to tighten them up a bit. I'll have my dad take a look at them next time I see him. http://www.twinsburggoodyear.com/brake-repair-twinsburg-oh

Unknown said...

How often do you actually have to replace the rotors? I know that the pads get replaced a lot more often, but the rotors must need to be replaced sometime due to the friction. It is nice they don't go out as fast as brake pads do. http://www.actionmuffleredmonton.com/en/services.html

Unknown said...


شركة مكافحة حشرات بجدة
تشكل الحشرات خطر كبير على حياة الإنسان عند تواجدها داخل المنازل والبيوت، ولهذا يجب أن يتم القضاء عليها باستخدام أفضل الطرق الأمنة، ولذا فأنت بحاجة إلى واحدة من شركات مكافحة الحشرات وهي الذي أصبحت أكثر انتشاراً بالمملكة ولكن عند التعامل مع واحدة من تلك الشركات يفضل أن تكون شركة يثق بها الجميع، ويثق في أدائها بالعمل، واليوم سوف نحرص على أن نقدم إليكم واحدة من أكبر الشركات الرائدة في مجال مكافحة الحشرات بجدة، وهي شركتنا شركة مكافحة حشرات بجدة، فشركتنا تحرص على استخدام أقوى المبيدات الحشرية القاتلة للحشرات بأقل وقت ممكن، كما أن
شركة تركيب طارد حمام بجدة

شركة مكافحة حشرات بجدة
شركة مكافحة صراصير بجدة
شركة مكافحة البق بجدة
شركة مكافحة النمل الابيض بجدة
شركة مكافحة الفئران بجدة
https://ahbabelmadina.com/شركة-مكافحة-حشرات-ورش-مبيدات-بجدة/


seocom said...

الصيانة المنزلية بجدة والمدينة المنورة للقيام بكافة ما يبحث عنه عملائنا من أعمال تمديد الغاز المركزي والسباكة والكهرباء والنجارة والدهانات وفني تركيب الدش بأمهر المتخصصين وأقل التكاليف وسرعة للتواصل مع عملائنا الكرام بجدة والمدينة.

سباك بالمدينة المنورة
كهربائي بالمدينة المنورة
دهان بالمدينة المنورة
نجار بالمدينة المنورة
معلم سباك بجدة
معلم كهربائي بجدة
معلم دهان بجدة

الفارس كلين said...



شركه تنظيف منازل بالخبر
شركه تنظيف خزانات بالخبر
شركه تنظيف شقق بالخبر
شركه تنظيف فلل بالخبر
شركه تنظيف كنب بالخبر
شركه تنظيف موكيت بالخبر
شركه مكافحه حشرات بالخبر
شركه تنظيف شبابيك ودريش بالخبر
شركه تنظيف منازل بالجبيل
شركه تنظيف مجالس بالباحه