SmartTractor

[jam]

A new toy

I also happened to obtain a SMARTstylus which is another useful tool made by Acoustical Systems.

Herr Brakemeier from Acoustical Systems is a genius when it comes to useful and accurate tools to align your cartridge.

I also regard this as a must have................you might wonder about the record clamp in the background, but that is a different story for a different thread.

Jam

P.S. Please note not to put the stylus down on a record mat like I have or you could lose a stylus, as David kindly pointed out. I had locked my platter and my mat is pretty smooth but still a bad idea.

 

[jam]

Teaser

Even the little guy approves...............

Jam

 

[pcosta]

Jam

I also bought a SME 3012R after being inspired by his setups. I only wish I had done it years ago.

I have a question about you set using a slotted headshell vrs the non adjustable SME headshell. What did you set the pivot to spindle distance at to use a slotted headshell.

 

[jam]

Yes David nailed it on that one, now I have a whole bunch of arms and protractors to get rid of.

I set the pivot to spindle distance at 295.6 mm and used a Sumiko slotted head shell , an Ortofon headshell (made by Jelco as well) will work just as well. I am not happy with the SME headshell unless you using a high compliance cartridge.

I did not use the SME head shell in this setup.

I will be trying a new head shell that is under development soon and I will report my findings. If you can swing it the Acoustical Systems head shell is good and gives you a rake angle adjustment.

If you want to try the Uni-Din alignment, Mr.Brakemeier suggest's 289.2 mm pivot to spindle (for the 3012-R) for optimum alignment. This alignment is only available with the SmarTractor.

Jam

 

[pcosta]

Thanks Jam

I have a friend that has the SmarTractor, so I can try it out the next time he visits. I still haven't tried different headshells.

I like the idea of the Acoustic Systems headshell, but I don't like the price.

 

[jn229]

I own a Wilson Benesch arm that has no markings to define the pivot point. If your arm has no pivot markings then I would use an arc style protractor. IMHO having your styli track a thin line arc would be more accurate then trying to guess a pivot point on an arm with no pivot point markings.

 

[jam]

jn229,

I beg to disagree, an arc style protractor only works if you have the exact pivot to spindle distance so if you can't measure the exact pivot to spindle distance or have you arm mounted in the exact position as required by the arc protractor it is useless. I find that I always get closer to the required setting with the SmarTractor, when it is used correctly.

Jam

 

[jn229]

Thank you Jam

I was thinking that there was room on the head shell to compensate for being off at the pivot. Your right of course about the spindle to pivot measurement needing to be spot on. An arc protractor only measure from the pivot to styli. Once my error was pointed out I must admit to being embarrassed that I did not realize this.

I spent the morning with some tape, calipers and dental floss, trying to accurately define the pivot point with a cross hair (er floss) marking to accurately mount my Benesch. The arm needed to be readjusted at the post. I am pleased enough with the results, that I placed a small touch of paint to define the pivot point.

Now there is this itch of realization in the back of my mind that even with this effort the arm could still be off by a mm or more )-:

 

[jam]

Hi jn229,

The best way I have found to check if you have the correct pivot point marked on the tone arm, as you have, is to use a protractor like a Feickert for example and place the pointer on the marked point, now rotate the arm and if the mark stays centered on the pointer you are on the pivot point. Now with the protractor check the spindle to pivot distance and that should be the same as that calculated for your protractor. If not move the arm or if not possible use the measured distance to generate a new arc protractor (there is a program avaiable on Vinyl Engine that will allow you to do this).

The bottom line is that you will need some form of protractor to do this correctly. I have corrected several friends and former customers (all who had paid for and used arc protractors like the Mint) because there were mounting distance errors.

The beauty of the SmarTractor is that you can compensate for these errors.

To avoid the pitfalls of an arc protractor something like a DB systems protractor can give you good results.

I don't mean to rain on anyone's parade but like using test equipment in the lab, the equipment needs to be calibrated for accurate results, in our case the pivot to spindle distance is of prime importance.

Jam

 

[jn229]

Hi jn229,

The best way I have found to check if you have the correct pivot point marked on the tone arm, as you have, is to use a protractor like a Feickert for example and place the pointer on the marked point, now rotate the arm and if the mark stays centered on the pointer you are on the pivot point. Now with the protractor check the stylus to pivot distance and that shod be the same as that calculated for your protractor. If not move the arm or if not possible use the measured distance to generate a new arc protractor (there is a program avaiable on Vinyl Engine that will allow you to do this).

The bottom line is that you will need some form of protractor to do this correctly. I have corrected several friends and former customers (all who had paid for and used arc protractors like the Mint) because there were mounting distance errors.

The beauty of the SmarTractor is that you can compensate for these errors.

To avoid the pitfalls of an arc protractor something like a DB systems protractor can give you good results.

I don't mean to rain on anyone's parade but like using test equipment in the lab, the equipment needs to be calibrated for accurate results, in our case the pivot to spindle distance is of prime importance.

Jam

Thanks for this tip. I immediately tried this and the new 'defined pivot point' remains very stable through out the arm's arc (surprisingly so).

I have a home made spindle to pivot measuring tool. My brother in law and I share a Feickert protractor, unfortunately it is at his home some 3hrs. away, will double check in future.

 

[jam]

What I do normally after I have set up my tone arm with the SmarTractor and I know the exact pivot to spindle distance, I generate a curve protractor and and compare the results. If anything, just to confirm nothing got bumped and moved after alignment. The SmartStylus is a great tool to get into the ballpark and the rest can be done ear or instrumentation. You might be surprised how far off you can be by just eyeballing it, especially when you are trying to get arm parallel to the record surface.

Jam

 

[jn229]

Thanks to Jam, I believe I have accurately aligned my arm. I own a Wilson Benesch arm and it has no pivot centre marking. Jam suggested rotating the arm through its arc and observe if a Feickert's indicator pin stayed above a centre mark. I did this with the arm cued up and marked a pivot point with a small drop of paint. Then, I discovered the arm's azimuth changed when the arm was lifted by its cue. If you own a unipivot arm, you can visually see the styli settle into a record's groove and align its azimuth. Also around this time I discovered that with the Benesch's egg shape bearing housing, the centre marking moved away from the Feickert's indicator when the arm was cued down.

Therefore I remarked a pivot centre on this Wilson Benesch, when the arm was cued down and in a record's groove.

I am posting this now because I just mounted a new cartridge and all the above once again became fresh in my mind. Hope this helps others with unipivots without pivot centre markings.

 

[Brian Walsh]

Thanks to Jam, I believe I have accurately aligned my arm. I own a Wilson Benesch arm and it has no pivot centre marking. Jam suggested rotating the arm through its arc and observe if a Feickert's indicator pin stayed above a centre mark. I did this with the arm cued up and marked a pivot point with a small drop of paint. Then, I discovered the arm's azimuth changed when the arm was lifted by its cue. If you own a unipivot arm, you can visually see the styli settle into a record's groove and align its azimuth. Also around this time I discovered that with the Benesch's egg shape bearing housing, the centre marking moved away from the Feickert's indicator when the arm was cued down.

Therefore I remarked a pivot centre on this Wilson Benesch, when the arm was cued down and in a record's groove.

I am posting this now because I just mounted a new cartridge and all the above once again became fresh in my mind.

Another option for measuring P2S distance on a unipivot is to measure from the bearing point or cup with the arm wand removed, which is more precise than swinging the arm around and trusting that it's level.

 

[jn229]

Another option for measuring P2S distance on a unipivot is to measure from the bearing point or cup with the arm wand removed, which is more precise than swinging the arm around and trusting that it's level.

Totally agree Brain, unfortunately have yet to discover how to remove the wand on a Benesch (just another aggregation why I would not recommend this arm). The manual says there is a locking collar but I could not decipher where this collar existed. An exposed bearing point would have made life easy.

 

[Kcin]

I can't recommend the SmartTractor more highly. I have had both Fiekerts ( the old one is more resolving IMO), numerous others including custom Mint Tractors ( very nice but maddening to use), DB systems, and many others in a box somewhere. The SmartTractor is so easy to use with its laser indentation and accurate Vernier scale.

I set up my two new cartridges in an hour spot on and I double and triple checked. I wish I would have purchased the more expensive model- forget the name now- but for the average vinylphile this set will get you there quickly and accurately... highly recommended.

 

[jam]

I can't stress the importance of getting the spindle to pivot distance correct especially with a curve protractor. The beauty of using the Smart tractor is that it can compensate for small errors in spindle to pivot distance which is impossible with a curve protractor. Unless you have a moveable arm board to correct errors usually errors creep in when drilling holes for arms and the slop in fitting of the arm. That is why I do not recommend the Mint protractor l, it only useful as a final check if you have the correct distances. Too many times I see turntables which have been set up with the Mint and have measured errors up to 5mm in the pivot to spindle distance. Which in my assumption makes the whole excersise pointless.

 

[PeterA]

I can't stress the importance of getting the spindle to pivot distance correct especially with a curve protractor. The beauty of using the Smart tractor is that it can compensate for small errors in spindle to pivot distance which is impossible with a curve protractor. Unless you have a moveable arm board to correct errors usually errors creep in when drilling holes for arms and the slop in fitting of the arm. That is why I do not recommend the Mint protractor l, it only useful as a final check if you have the correct distances. Too many times I see turntables which have been set up with the Mint and have measured errors up to 5mm in the pivot to spindle distance. Which in my assumption makes the whole excersise pointless.

Yes, there are benefits to having a moveable armboard. I have an SME sled mount and do use a MINT protractor. I find that it is very accurate, but I went to great pains to calculate the pivot to stylus distance from which my MINT was made. I would love to also have a SmartTractor or the UNI Pro, particularly for ease of use.

 

[jam]

One of the many reasons I like the Micro Seiki turntables and now the Air Force III is the arm mounting arrangement allows you two axis of rotation to get the stylus where it needs to be. The SME allows you some degree of freedom for adjustment which Peter mentions, but most other arms don't.
Which brings us back to problem of using a fixed arm board and a tonearm with no adjustment range, which is most of the arms out there.
I wish more manufacturers would mark the pivot point on their tonearms, which would help simplify matters to some degree. I have been amazed to find that most protractors provided by tonearm manufacturers are wrong.............just some food for thought.

 

[Marcus]

A word of caution. With the SMARTractor you can measure S2P distance only up to 315mm. So it's useless in this regard for 14' and longer tonearms such as Kuzma 4Point 14 inch which requires 342mm of S2P distance. On the other hand, this will not be a problem in 9,9 out of 10 cases.

 

[Marcus]

The Feickert protractor (at least the older version that I have) can handle even 16' tonearms. Also, there is some controversy about the (only) one null point adjustment. Kuzma for instance is very reserved about this and recommends two null point adjustment which is not so critical if you're not absolutely precise.