Alex
Nordschleife
- Joined
- 6 Mar 2014
- Messages
- 22,175
As some may know I went to the local Kwik Fit the other day to have my alignment done and check out the Hunter Hawkeye system. Thought I'd do a little write-up about my observations and also maybe have a discussion on the system. I'll maybe do a write-up on my actual car's tracking as it's for a different discussion to this.
So, once I drove my car up on the ramps and the Kwik fit fitter swiftly closed the doors behind me (as he believed leaving the doors open fluctuated the readings) and we were on to the computer to start the process. Within minutes I was presented with a screen with all the parameters the machine measures and the tolerance bands for each one. They went something like this:
Front
Camber - 0 to minus 30 minutes
Caster - 8 degrees +/- 30 minutes
Toe - 0 to 5 minutes
Rear
Camber - minus 55 minutes to minus 1 degree 25 minutes
Toe - plus 5 minutes to plus 15 minutes
These are for the Carrera 4 996 and obviously other models differ.
Now my initial observation before we even did anything was, the international general rule of thumb of any measuring system is it MUST be 10 times more accurate than the tolerance band being measured. Anyone who knows anything about measuring will dismiss any measuring system not capable of doing so. It wouldn't even get through the front door of a quality department. So, the tolerance band of the front Toe is 5 minutes (and rear 10 minutes). The incremental resolution of the Hunter Hawkeye is 1 minute (on the display). Obviously 10 times more accurate that a 5 minute tolerance band would be an accuracy of 30 seconds. Or to put it the other way, the smallest tolerance band the Hunter Hawkeye would be deemed acceptable to measure would be a 10 minute tolerance band. So not acceptable to measure the front Toe and only borderline to measure the rear Toe. I think we can accept it is acceptable to measure the Camber and Castor as their tolerance bands are much greater.
On to getting some measurements. The fitter fit the wheel target quick grip adaptors. Now these just hook on over the tyres holding the adaptors flat against the alloys. There didn't seem any need to ensure they were sat central against the wheel but the fitter did check they were flat up against the wheel and in my case sat against all 5 knuckles of each spoke. Once all 5 are fitted the fitter then has to do some sort of process where I can only presume the overhead camera that do the measuring are setting some form of Datums to work from as the fitter turns the steering lock to lock (without engine running so no power steering) and then roll the car forwards until the computer says stop.
Once this process has been done, the computer then goes through the process on measuring all the parameter of alignment. I don't know how the software is written so don't know whether the program can compensate the the wheel adaptors not being central or any slight run-out of a face of an alloy wheel. A quick bit of trigonometry tells us that over a distance of 200mm (say the diameter of where the adaptor sits on the alloy) 5 minutes equates to around 0.3mm - not much!
Once all measurement are taken, the fitter then goes through each corner turning the relevant nuts and bolts (shown on the computer) until the reading goes from the red (out of spec.) into the green. All very simple and interesting to watch as each adjustment is made. Once all adjustments are made, the fitter then hits 'print' and the printer churns out a nice diagram of 'before' and 'after' of all parameters measured. All very interesting and good visual graphics to explain to the greatest novice what's actually being measured and adjusted. Pay the bill and you're on your way.
The deal was free check. £50 for any front end adjustment, £25 for each rear wheel adjustment (So £100 if any front and both rears need a tickle). For £120 you have a 2 year warranty with as many checks in that time window you want and 8 checks where adjustments are made, however much adjusting needs on each check. This can be done by driving in to any UK Kwik Fit establishment with a Hunter with just your name and reg. plate.
Obviously I took this deal out, especially when we were unable to get every parameter in spec.
Now a few questions from me that aren't addressed by Kwik Fit, Porsche, Hunter's website or anywhere else I had a quick browse on the web:
1. How can a system not deemed acceptable to measure some of the parameters be acceptable?
2. Does tyre pressures influence the readings of the system?
3. Should the car have a full tank of fuel, or empty, or halfway - would this influence the readings?
4. How repeatable is the system?
5. Define accuracy as all that's stated by Hunter is it's accurate?
After the fitter had finished making adjustments and we were happy with the results, I asked him to reset the computer, re enter model, etc. and do the test again. The results were different - to the point that some in spec. were now out of spec. :dont know:
I'm talking differences of 7 minutes to 20 minutes on rear LH Toe. 1 minute to 7 minutes on rear RH Toe. Also 1 minute and 5 minute discrepancy on both rear Cambers.
In a couple of weeks I'll bob in again for a free check and see what results they give me then.....also I'm due some new back tyres soon so will bob in again once those are fitted.
Hunter's USP seems to be "Other wheel alignment machines don't come close to matching the productivity and profit enhancing power of the HawkEye Elite® wheel alignment machine." "Say goodbye to wasted shop time"
Most guff on their website seems to be about speed and profit and not much in terms of accuracy. :dont know:
Now I'm in no way saying this isn't the best system on the market, or even rubbish, but just want to get my head around the importance of the accuracy of this kit and also the tolerance bands Porsche specify that the car should be within. Is it all smoke and mirrors, is the equipment capable, are the specs. baloney?? :?
Discuss.
So, once I drove my car up on the ramps and the Kwik fit fitter swiftly closed the doors behind me (as he believed leaving the doors open fluctuated the readings) and we were on to the computer to start the process. Within minutes I was presented with a screen with all the parameters the machine measures and the tolerance bands for each one. They went something like this:
Front
Camber - 0 to minus 30 minutes
Caster - 8 degrees +/- 30 minutes
Toe - 0 to 5 minutes
Rear
Camber - minus 55 minutes to minus 1 degree 25 minutes
Toe - plus 5 minutes to plus 15 minutes
These are for the Carrera 4 996 and obviously other models differ.
Now my initial observation before we even did anything was, the international general rule of thumb of any measuring system is it MUST be 10 times more accurate than the tolerance band being measured. Anyone who knows anything about measuring will dismiss any measuring system not capable of doing so. It wouldn't even get through the front door of a quality department. So, the tolerance band of the front Toe is 5 minutes (and rear 10 minutes). The incremental resolution of the Hunter Hawkeye is 1 minute (on the display). Obviously 10 times more accurate that a 5 minute tolerance band would be an accuracy of 30 seconds. Or to put it the other way, the smallest tolerance band the Hunter Hawkeye would be deemed acceptable to measure would be a 10 minute tolerance band. So not acceptable to measure the front Toe and only borderline to measure the rear Toe. I think we can accept it is acceptable to measure the Camber and Castor as their tolerance bands are much greater.
On to getting some measurements. The fitter fit the wheel target quick grip adaptors. Now these just hook on over the tyres holding the adaptors flat against the alloys. There didn't seem any need to ensure they were sat central against the wheel but the fitter did check they were flat up against the wheel and in my case sat against all 5 knuckles of each spoke. Once all 5 are fitted the fitter then has to do some sort of process where I can only presume the overhead camera that do the measuring are setting some form of Datums to work from as the fitter turns the steering lock to lock (without engine running so no power steering) and then roll the car forwards until the computer says stop.
Once this process has been done, the computer then goes through the process on measuring all the parameter of alignment. I don't know how the software is written so don't know whether the program can compensate the the wheel adaptors not being central or any slight run-out of a face of an alloy wheel. A quick bit of trigonometry tells us that over a distance of 200mm (say the diameter of where the adaptor sits on the alloy) 5 minutes equates to around 0.3mm - not much!
Once all measurement are taken, the fitter then goes through each corner turning the relevant nuts and bolts (shown on the computer) until the reading goes from the red (out of spec.) into the green. All very simple and interesting to watch as each adjustment is made. Once all adjustments are made, the fitter then hits 'print' and the printer churns out a nice diagram of 'before' and 'after' of all parameters measured. All very interesting and good visual graphics to explain to the greatest novice what's actually being measured and adjusted. Pay the bill and you're on your way.
The deal was free check. £50 for any front end adjustment, £25 for each rear wheel adjustment (So £100 if any front and both rears need a tickle). For £120 you have a 2 year warranty with as many checks in that time window you want and 8 checks where adjustments are made, however much adjusting needs on each check. This can be done by driving in to any UK Kwik Fit establishment with a Hunter with just your name and reg. plate.
Obviously I took this deal out, especially when we were unable to get every parameter in spec.
Now a few questions from me that aren't addressed by Kwik Fit, Porsche, Hunter's website or anywhere else I had a quick browse on the web:
1. How can a system not deemed acceptable to measure some of the parameters be acceptable?
2. Does tyre pressures influence the readings of the system?
3. Should the car have a full tank of fuel, or empty, or halfway - would this influence the readings?
4. How repeatable is the system?
5. Define accuracy as all that's stated by Hunter is it's accurate?
After the fitter had finished making adjustments and we were happy with the results, I asked him to reset the computer, re enter model, etc. and do the test again. The results were different - to the point that some in spec. were now out of spec. :dont know:
I'm talking differences of 7 minutes to 20 minutes on rear LH Toe. 1 minute to 7 minutes on rear RH Toe. Also 1 minute and 5 minute discrepancy on both rear Cambers.
In a couple of weeks I'll bob in again for a free check and see what results they give me then.....also I'm due some new back tyres soon so will bob in again once those are fitted.
Hunter's USP seems to be "Other wheel alignment machines don't come close to matching the productivity and profit enhancing power of the HawkEye Elite® wheel alignment machine." "Say goodbye to wasted shop time"
Most guff on their website seems to be about speed and profit and not much in terms of accuracy. :dont know:
Now I'm in no way saying this isn't the best system on the market, or even rubbish, but just want to get my head around the importance of the accuracy of this kit and also the tolerance bands Porsche specify that the car should be within. Is it all smoke and mirrors, is the equipment capable, are the specs. baloney?? :?
Discuss.