There is an old thread awhile back that touches on the Adams machine.
They are very easy to use, with any film that has the "tooth" incorporated into the base of the film. Most of your retouching will be done on the base, not the emulsion side of the film. Film without the "Tooth" will require something to get the lead to adhere to the slick base. In the old days we used "Retouching Varnish" as none of the films available had the tooth necessary to hold it to the negative. Retouching can be done on the emulsion side of the film, but was seldom done during the 50's through
the 90's, because it is very difficult to make your retouching blend in without ever touch of the pencil showing in the final print. So the retouch work should be done on the base side so that when the negative is printed the emulsion grain is focused sharp. However the base where the retouching has been done will be (due to the thickness of the film and emulsion) slightly above the actual point of focus and thus be rendered somewhat diffused and out of focus. This helps to blend the retouch pencil marks to nearly invisible. If you can see the retouching in the final print you didn't do it correctly, usually to much pressure (Heavy hand) or to high a speed on the vibrator. Dyes can be applied to either side, but it is still best to use them on the base or non emulsion side. Good retouching can not be seen by a viewer of the print.
Your Pencil should be sharpened to a sharp taper approximately 1 1/2 to two
inches long. I am talking about drafting leads being held in an adjustable
collet type lead holder. I know of no professional retoucher ever using wood pencils etc. A good lead to practice with on a negative that prints well on a 2 grade of paper is an HB. To sharpen properly simply fold a piece of 220 grit sand paper in an envelope at least two inches deep the tape the sides with masking tape. Also make one with 400 to 600 grit for your finish sharpening. Take the blunt end of the lead into the 220 grit envelope and pump it up and down while rotating it in the envelope. Use the fine grit the same way to finish your pencil tip. The lead when done this way will be as fine as a hair you wish to eliminate. The extremely fine tip will break very easily, this is your insurance policy from too much pressure. Go slow, let the machine create the stroke. It will take practice and experimentation to
find your favorite leads for your negatives. My description here is how we did it in the dark ages. Truly wish I could have bought my machine at todays prices rather the major bucks I paid years ago.