dots on surface of records

[jason]

hi mates,

I have one question regarding with the 'dots' on the surface of our record pressings.

Recently we found these marks appear randomly, sometime many, sometime few or not. This is one of the worst (see the pic). I took a look with a microscope, it seem these are broken lines or filled insufficiently. What can cause it? Or do you probably know what to be adjusted? thank you so much.

[THD]

I'm not sure, but this looks like it is the advanced ball, It seems to appear when there is some heavy vertical amplitude( a lot of bass out of phase, use EE filter) and the advanced ball stops the cutterhead from moving to far this direction and then dig into the lacquer, I had some signs of this earlier with my Westrex 3DII cutterhead on a Scully LS-76, but when I changed the advanced ball to a new one it stopped doing that, ask the one who cut this to take a close look on the advanced ball, if that's what this is? Another thing is that the advanced ball should be set to go where the groove is (so that the next groove that comes hides this), not next to the it....

[Aussie0zborn]

This is called “stitching” and it appears randomly. It has been discussed here many times. Use the search function in the forum and search for “stitching”.

[jason]

thank you so much, I will check it out.

This is called “stitching” and it appears randomly. It has been discussed here many times. Use the search function in the forum and search for “stitching”.

[jason]

thank you, I think it is the 'stitching'.

I'm not sure, but this looks like it is the advanced ball, It seems to appear when there is some heavy vertical amplitude( a lot of bass out of phase, use EE filter) and the advanced ball stops the cutterhead from moving to far this direction and then dig into the lacquer, I had some signs of this earlier with my Westrex 3DII cutterhead on a Scully LS-76, but when I changed the advanced ball to a new one it stopped doing that, ask the one who cut this to take a close look on the advanced ball, if that's what this is? Another thing is that the advanced ball should be set to go where the groove is (so that the next groove that comes hides this), not next to the it....