How much should this cost? And how much time should it take?

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Hey all I have a pair of rotors where I need the hub bore opened up from 67.8mm to 70.6mm. I was originally going to do it myself by making a jig using old rotors and bolting the rotor down and using a 70mm hole saw or possibly a cylinder hone. Everyone I talked to said they wouldnt mess with it and just to bring it to a machine shop. I was hesitant at first because I like doing things myself but after thinking about it for a while I said screw it that would be the better way. I called 12 local machine shops today, 10 of which said they didnt want to do it. One of them said they would do it but they charge a $75 flat fee plus whatever time it takes and said he would need them for an entire day. The other said he would have to set it up on the machine and see how long it takes him but he couldnt get me a price until he does so and also said it would "probably be time consuming". So basically the guy has me over a barrel at that point and could charge me whatever he wants once he has the rotor on the machine.I was all willing to spend $50 (people that have gotten it done on my forums have stated 20-50 bucks) on it but all of these well equipped shops are making a big deal out of it by flat out denying it or scaring me into thinking its some kind of big deal. I understand precision costs money but theres a point where it just seems like a rip off to me. So I figured I would post on here to get some opinions of people that actually do this for a living or mess around with it as a hobby. Does it really take "a long time" to put the rotor in a machine and dial it in and machine out 3mm? At this point im back to doing it myself in a drill press bolted to my jig using either a hole saw or cylinder hone.
Reply:The reason shops are turning it down is because modifying safety components is a major liability.I won't do it for a road use vehicle, but if I was going to do it on a go-kart or something, I'd expect to spend about half an hour per rotor to dial it in and cut it.  Could be as quick as 5 minutes per rotor if ya get lucky during the set up.My name's not Jim....
Reply:Exactly.  It's not that they can't do it. It's more that the $100 is not worth you coming back and suing them when the rotor fails.  It's an easy job.
Reply:It's all about liability.   Sad state that America is in...  Read the Case against Lawyer by Christine Crier.  it will really open your eyes to how furked up America has become.....  its lawyers, politicians and big business trio that is killing usTiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:Originally Posted by BoostinjdmThe reason shops are turning it down is because modifying safety components is a major liability.I won't do it for a road use vehicle, but if I was going to do it on a go-kart or something, I'd expect to spend about half an hour per rotor to dial it in and cut it.  Could be as quick as 5 minutes per rotor if ya get lucky during the set up.
Reply:I'm curious, why do you need this done?Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:I assume to mount bigger rotors on his car. There shouldn't be a problem with this. Rotors and redrilled and bored every day all over the country by all kinds of shops.What size are the rotors over all? This might be part of the problem why some shops are turning you down. The rotors may be bigger than they can swing.
Reply:Originally Posted by MinnesotaDaveI'm curious, why do you need this done?Dave J.
Reply:14" isn't so bad, I would figure most real machine shops should be able to swing that. However like mentioned I would guess many shops hear brakes and that is enough for them to say no. Just keep looking, you'll find a shop that will do them. Are the ctsv rotors two piece or one?I have seen people go as far as using a die grinder and burr tool to open up wheels and rotors.
Reply:Originally Posted by VPT14" isn't so bad, I would figure most real machine shops should be able to swing that. However like mentioned I would guess many shops hear brakes and that is enough for them to say no. Just keep looking, you'll find a shop that will do them. Are the ctsv rotors two piece or one?I have seen people go as far as using a die grinder and burr tool to open up wheels and rotors.
Reply:Did you explain to the machine shop that it is not the bearing surfaces that you want larger, but the rough cast material between the bearings?  It may make a difference in the cost and their desire to take on the job.
Reply:If you were close, I would just let you come over and help you do it yourself for free.  It really is an easy enough setup.  Any shop should be able to swing 14".  I can do 11" on my little lathe.  But you could do it on a mill with a rotary table as well.  It is definitely the liability/hassle per $ they don't want.I would definitely consider shaving the axles though, then you could use off the shelf rotors.
Reply:I would do it for laffs..Me no scared....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Bring it to PEP BOYS and ask for Julio with the gold teeth and a tattoo on his neck that says Mariella. He's a trained brake technician and will give you a legit answer. Don't listen to the guys here, espescially ZAP he's only a hobby machinest  I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:Stop by your local Napa (or equivalent) auto parts store and they should be able to steer you to an automotive machine shop. Most other machine shops avoid automotive work because it isn't profitable like aerospace. You need an old school job shop. I'd do it if I was closer... although I don't normally work on Chevy's. If you'd like to do it yourself I'd recommend you read the awesome post by fabn4fun. He made a line bore for his drill press pulled off some wonderful results.http://weldingweb.com/vbb/showthread.php?t=187741Another option would be a flycutter... I did some experiments with a craftsman version on my drill press. http://weldingweb.com/showpost.php?p...41&postcount=8The correct way would be on a lathe of course. Not sure how anyone gets by without a lathe.
Reply:lol on the Chevy comment. Thank you for the reply forhire. You dont think a bi metal hole saw will cut it? No pun intended. I was thinking either the hole saw or cylinder hone.
Reply:Originally Posted by Threadkillerlol on the Chevy comment. Thank you for the reply forhire. You dont think a bi metal hole saw will cut it? No pun intended. I was thinking either the hole saw or cylinder hone.
Reply:I would opt for turning the hub down as well, keeps you from having this problem every time you need to do the brakes.
Reply:Originally Posted by weldermikeBring it to PEP BOYS and ask for Julio with the gold teeth and a tattoo on his neck that says Mariella. He's a trained brake technician and will give you a legit answer. Don't listen to the guys here, espescially ZAP he's only a hobby machinest
Reply:I think you will get very different answers on the phone than you will if you walk into a place with the part in your hand saying "I need this bored out to x.x"on the phone you're just an interruption, asking about a little nothing job, probably calling a bunch of different places and it's easy and no skin of anyones back to just blow you off... in person they can see the thing and realize that they can chuck this up and bore it in no time, you're not just some unknown caller asking about an unknown thing. walk into  place that has the capability and I think you'll get a much different answer is my advice...miller 330a bp TIGmiller dynasty 200DX TIGmillermatic 185 MIGthermal dynamics cutmaster 101 plasma cuttersnap-on YA5550 plasma cutterhypertherm powermax 30 plasma cutterbaileigh CS225 cold sawetc....
Reply:That is good advice. Put a part in someone's hand and I bet they do it.Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:That is great advise!
Reply:This is an easy job for someone that has a lathe with 14" swing.... most any machine shop should be able to do this in an hour or less...Lincoln pro mig 180Lincoln Square Wave Tig 300/wp 20/home built water cooler Victor, Purox, Harris, O/A welding/cutting setupsVintage Craftsman drill pressVintage Craftsman/Atlas 12"x 36'' lathe7''x 12'' w/c band saw Everlast 140 st
Reply:To answer the question on liability. While you are right, it isn't a major deal you are looking at it from an intelligent perspective. The legal perspective is this.. Who was the person who last worked on that part? Did they modify the part from original design? Do they have engineering plans proving this wouldn't weaken the part and contribute to it's failure?I'm a gunsmith by trade. I have people all the time ask me to modify trigger mechanisms to shorten the pull. To truly shorten the pull on many modern guns would require changing the geometry of parts. I CAN do it, I have done it to some of my own guns. My insurance company who issues my liability insurance policy has flat told me, "Don't make your own parts for a fire control group. We will drop you." They allow me to adjust, stone, and polish triggers to improve their function as designed, not redesign  the original system. Just my experiences in a different field, but still very similar.
Reply:Originally Posted by turbocad6I think you will get very different answers on the phone than you will if you walk into a place with the part in your hand saying "I need this bored out to x.x"on the phone you're just an interruption, asking about a little nothing job, probably calling a bunch of different places and it's easy and no skin of anyones back to just blow you off... in person they can see the thing and realize that they can chuck this up and bore it in no time, you're not just some unknown caller asking about an unknown thing. walk into  place that has the capability and I think you'll get a much different answer is my advice...$50 bucks is too cheap. That would cover setup only. Then another $40 per rotor. And then it would be a cash job, no paper trail.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Honestly what would be the setup for turning the bore of some rotors? Throw them on the 3 jaw and put the boring bar in the QCTP. Thats less work than pouring coffee in the morning.