Cartridge Alignment Protractor - DIY?

[mozcho]

In my country these things (hifi related) are rare and expensive. I chanced upon the following page, where we can download free cartridge alignment protractors:

https://www.vinylengine.com/cartridge-alignment-protractors.shtml

Would this work? Or, are these general or cartridge-specific, say, a Rega RB300 arm would need one designed for it?

 

[savatage1973]

The alignment protractors available on Vinyl Engine will work for you and are available for free--you have to register to have access to them, but that is also free. Just make sure that when you download and print them that your printer is set to 100% (not "fit to page") or they may get "scaled" and not be accurate. Most of them have some sort of reference scale on them that you can measure with a ruler to make sure they are printed at the proper size.

 

[tnsilver]

Use @ConradH TemplateGen software (3rd link from the top) to print your own protractor. I think many of the other free protractors are based on Conrad Hoffman's work anyway.

 

[gadget73]

I've used the ones from VE, they work fine. Just make sure you measure the "scale" line and verify that the printed line matches the measurement it says it should. If it does not, then you get to fiddle with settings on the printer to get it right.

 

[kirk57]

Would this work?

Yes.

 

[bang4buck]

Yes, they work, but the problem is making sure that your printout is accurate. Check it with several rulers. I have two 30cm rulers right here on my desk and they disagree by over 0.5mm over the 30cm length. One is from a Las Vegas souvenir shop while the other is from a drafting supply store so guess which one I go by...

By the way, if you get frustrated with trying to adjust the printer scale just right, you can also draw your own protractor. Just mark, as accurately as you can, the spindle and your chosen null points on a piece of ruled paper. You'll end up with something resembling the Heybrook and Linn protractors on VE. This, again, calls for a reliable ruler. You'll also need to accurately cut or punch the spindle hole, but the same is true if you print the protractor from a file.

 

[gadget73]

One is from a Las Vegas souvenir shop

Does it read bigger numbers than reality? If so its either for measuring fish or *ahem* other things.

 

[WaynerN]

Our own ConradH has a nice program that prints out an alignment........Just enter in the pivot to spindle distance and pick an alignment.

http://conradhoffman.com/chsw.htm 3rd one down.

Piss on the VE.

 

[neevo]

A handy tip for cutting the spindle hole is to cut a triangle. Much easier to cut and perfectly centres the spindle.

 

[MRL_Audio]

+1 on Conrad’s work. Very flexible and functional.

 

[mozcho]

Thank you all, I have registered at VE and also found Hoffman's site. Will find time to print it out.

 

[revox-b77]

Our own ConradH has a nice program that prints out an alignment........Just enter in the pivot to spindle distance and pick an alignment.

Is pivot to spindle distance = to effective length - overhang?

 

[WaynerN]

Is pivot to spindle distance = to effective length - overhang?

Yes, that is correct. My Technics has an overall spec of 230mm. Its overhang is 15mm, therefore the tonearm pivot to spindle distance is 215mm. All geometry of every known alignment is based on the pivot to spindle distance. The overhang figures make it easy to use an inexpensive tool to align, like the Technics overhang gauge.

 

[EngineerNate]

A handy tip for cutting the spindle hole is to cut a triangle. Much easier to cut and perfectly centres the spindle.

I cut four "slashes" in a star pattern through the center of the hole. Centers nice and it's easy to start/terminate the cuts on the line with a razor blade.

 

[revox-b77]

My hole punch ( notebook flavor ) just happens to be the perfect size.

Thanks @WaynerN.
Are we using "Typical" or Din or Iec?

 

[DustyOldPile]

I cut four "slashes" in a star pattern through the center of the hole. Centers nice and it's easy to start/terminate the cuts on the line with a razor blade.

Same here. Back to using the paper one. My wonderful mirrored one from turntablebasics.com fell off the roof of my car, where I had temporarily set it. I'm afraid to try to order another from him after the horror stories I've heard of late.

 

[EngineerNate]

I like the mirror ones in theory, but I hate having to fiddle with both the fore-aft and angular adjustment of the cart to find the right spot. With the true arc protractors you can find the right fore-aft by aligning with the arc and then tweak the angle using the grids once you've got the cart the right distance from the pivot.

 

[WaynerN]

My hole punch ( notebook flavor ) just happens to be the perfect size.

Thanks @WaynerN.
Are we using "Typical" or Din or Iec?

I do the IEC, just because. The DIN is German, I believe.