Consultation on head tilt in EMBOSSING method

[WANCHO]

Query with "embossing" mode. I wanted to ask a question, I am following David Nelson's project and I have a doubt, in embossing, the stylet has to be at an 18º inclination on the perpendicular of the torque, but in Nelso's design there is a union piece between the cutting head and the rest of the assembly that tilts the head even more (photo attached).
Can someone explain to me why the head is tilted so downward? I ask this because in my design this gives me the problem that part of the coil support collides with the surface of the disc as can be seen in the image. By lowering the stylet further this should not be a problem since you would gain elevation. Can someone with experience in "embossing" tell me why this inclination?

thank you!

[farmersplow]

Unfortunately, I am not familiar with the David Nelson project in detail. But you write about embedding, and what you present here is cutting. When cutting, you work with a rake angle greater than (or equal to) zero.
In embedding, the rake angle is negative.
In your illustration, the rake angle is about +35°. This means cutting, although you don't even cut steel with this high angle!
I cannot see what the 18° angle is supposed to be.

VTA 01.png

Different rake angle

Maybe you have installed the torsion bar upside down? If you install it the other way around, then you have a negative "rake angle" (embedding angle), a greater distance to the plate and a lower angle at the cutting head connection. This could solve your problems.

photo_2023-09-20_18-49-36c.png

A modification of your image

Greetings from Austria
Thomas

[pentlandsound]

Hi both,

It looks, from the first picture above, as though the torque tube is upside down; in my recording head design, the torque tube has its stylus hole bored at 18º off vertical (trailing angle). I designed it this way because, in my earlier heads, this had proven to be an optimal angle for embossing (with the styli then available to me). I designed two different brackets for attaching the head to the bearing plate. One has a right-angled back, so that when the head is bolted to it, the torque tube is parallel to the disc surface and the stylus meets the disc at 18º trailing. The other, as seen in the images above, has an acute-angled back, so that the whole head is tilted by 18º, and the stylus ends up vertical. The purpose of doing this was so that the same head might be used - after switching brackets and styli, and altering down-force - for both embossing and cutting. (For the latter, there is also the potential side-benefit of a closer alliance with vertical tracking angle - although opinion is divided as to whether this does add any value. It doesn't apply for embossed recordings.)

As things would happen, during testing of this new head I had by far the best results embossing with PIAPTK/Presto sapphires. These styli should be presented to the disc almost vertical, and so the acute-angled bracket is used in conjunction with my recording head, with its compensating angle.

Hope this clears things up!
David

[WANCHO]

You are right, the angle of my model is 18° and I have most certainly put it upside down and I could be wrong, but I am glad that you answered me to clarify my doubts, I wanted to do embossing with tungsten in David Nelson's project on Embossing has a specific inclination and its design is like that, but I didn't know that it could be cut and not embossed with tungsten. Those illustrations that you have given me make me decide to cut with tungsten, in fact there is a thread in this forum on how to do homemade sharpening with TIC welding rods. I am going to place my Torque the other way so that the angle is 35 as it says, but I think it would be better and easier to set it to 90° since it can be cut with tungsten. Thank you very much friend, it has helped me a lot.

[WANCHO]

Thanks David, I based it on your project but since I am completely new in this field I am stumbling, I am already taking advantage of this thread because what I would really like is to CUT and not emboss and I want to do it with TIC tungsten welding rods which is the closest What can I do now? I have seen the images that the colleague farmersplow has uploaded and the truth is that it has clarified many doubts for me. But if you recommend the best option for cutting with tungsten with illustrations, I would appreciate it, although I already said that with the images uploaded by my colleague my calculations work out better. Your recommendation is appreciated.

[WANCHO]

this is a 3D sketch of my head

[WANCHO]

Thank you very much for your clarifications

[WANCHO]

Would the 90° tungsten cutting method as seen in the images give a stereo engraving sample? or in mono.