For what it's worth, don't get fooled by the whole adjuster hype, personally i believe they were and are a bit of a gimmick, and have little to do with a good plane. I often get really frustrated when people talk about backlash and the quality of an adjuster in a Norris type plane as if it mattered.
Any reasonably experienced lathe user will tell you that backlash is made irrelevant by someone who compensates for it. In the case of lathes, all you need do note the direction in which you are adjusting the tool(is the thread pushing or pulling) and then keep to a reference mark on the handwheel. It is similar with a plane adjuster. If you advance the knurled adjuster to point A, take note of where it is. Then turn it counterclockwise, firstly taking up the backlash, until it starts to back off the iron, and then continue to back off by enough so that you are well back from your point A. When you change back to clockwise, it will firstly rotate through however much backlash you've got , but then you just advance the blade to the exact point A which you started with. If you make sure you know which way your moving the blade and know the rotational position of the adjuster, then backlash could be twenty turns, it doesn't matter, you still advance +/- in relation to point A. On a shoulder plane iron, the snecked cutouts allow you to tap the iron backwards, to lessen the cut.
To be honest, most people who spend some time using both types, find that a wooden adjusterless plane, is far more precise and subtle than even the best Holtey adjuster. I would recommend getting an old timer to show you how to advance a blade with taps from a small hammer or mallet. Personally, like many people, i didn't get just how light a tap they mean when they say light. When i was learning with 19th C. moulding planes, an old carpenter from Northampton advised me that to adjust correctly, when you are approaching the blade taking a cut, if it is too hard for a pint glass, then it's too hard for a fine set on a plane iron. Funny example, but it got me to appreciate how sensitively you can tweak the cut. Lateral adjusting is as simple as tapping on one side of the iron or the other. It takes a while, but when you pick it up, it'll become automatic and you'll do it as easy as driving. I still use an old 4oz crosspein for most work, but a bench dog or even a bit of scrap steel will give you the ability to advance the iron by fractions of a thou.
Re the shoulder plane dovetail cutter, 60 works fine for me, as does 70. I did a couple of planes early on using 45, but the corners can become a bit accute and therefore difficult to fill during peening. Sorry for the long message, but i thought that i'd offer a couple of friendly tips that i would of loved when i did my first.
Get the tails to fit as closely as possible and you'll minimise the risk of those dreaded voids which ruin so many amateur D/T planes.
Use a light 8oz or 12oz ballpein, don't hit hard, very light, frequent taps helps you adapt quickly to the flowing metal.
Buy a good quality ball end punch to drive the metal into the corner and when you think you've done enough, take an extra 5-10 minutes, making sure you spread as much material toward and into the meeting lines.
A poorly clamped plane will move immediately when hit. If you can, make a peening block that holds the sides captive in recesses and bolts through the sideplate. You can add and take off extra clamps as you work, to make doubly sure that everything stays where you want it. Aluminium blocks, drilled and tapped for manifold studs work brilliantly.
Make a small protective guard from a small bit of scrap sheet metal or even cardboard and place this near where your peening to absorb the inevitable stray hammer blows. sounds trivial, but every maker learns that these marks take ages to remove if you're lucky and if you're not, then you might end up with voids from removing too much metal during clean up.
When you do clean up, a coarse file or belt can fatigue the brass or steel at the meeting edges of the pins/tails, resulting in tearout voids appearing. Switching to a finer grit in good time, when you've done the coarse tidying up, will take longer, but equally spending a nervous time, getting out deep scratches that didn't need to happen is no fun either.
Don't do the final lap of the sole without fitting the iron in, slightly backed off. The clamp or wedge on a shoulder plane will visually deflect the blade ramp when set for a cut, meaning that you'll have a humped sole if you lap without the blade fitted and tensioned.
Hope that helps and look forward to seeing some pics of the finished plane.
all the best, Nick.
