Often after you resurface a platen, it slightly changes the configuration of the platen with respect to the typeface. As a result one usually may need to do three adjustments in a specific order to get things to align properly again. These can definitely be done at home with some patience.

Usually the order for tweaking is: * Ring and Cylinder adjustment (distance of platen from typeface; the type shouldn't touch the platen or you'll find you're imprinting on your paper, making holes in the paper and/or ribbon, which isn't good). Sometimes using a simple backing sheet can remedy a bit of this distance problem, especially on platens which have hardened or shrunk slightly over time. * On Feet adjustment (vertical adjustment so that letters are bright and clear and neither top or bottom of characters are too light/faint) Repair shops will often type /// or a variety of characters with longer ascenders/descenders to make sure that the type is clear from top to bottom. * Motion adjustment (the lower and upper case letters are at the same level with respect to each other) The best way to test this is to type a center character like HHHhhhHHH to see if they line up on the bottom (the last three Hs are usually done with the Shift Lock on to make sure that's properly set).

You can search YouTube videos for your model (or related models) and these words which may uncover someone doing a similar repair, so you have a better idea of what you're doing and where to make the adjustments.

Here's Joe Van Cleave describing some of it in one of his early videos: https://www.youtube.com/watch?v=C0AozF2Jfo0

The general principles for most typewriters are roughly the same with slight variations depending on whether your machine is a segment shift or a carriage shift. You should roughly be able to puzzle out which screws to adjust on your particular model to get the general outcome you want.

Related blogposts: * https://munk.org/typecast/2022/01/23/adjusting-ring-cylinder-on-a-brother-jp-1/<br /> * https://munk.org/typecast/2013/07/30/typewriter-repair-101-adjusting-vertical-typeface-alignment-segmentbasket-shift-typewriters/

You might find a related repair manual for your machine with more detail and diagrams for these adjustments via the Typewriter Database or on Richard Polt's typewriter site.

For those not mechanically inclined you may be better off taking it onto a repair shop for a quick adjustment. https://site.xavier.edu/polt/typewriters/tw-repair.html 

Reply to u/Acethease at https://www.reddit.com/r/typewriters/comments/1d76ygx/got_a_as_a_gift_corona_3_recentlyish_and_i_need/

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I'm seeing this issue on my 1949 Royal QDL. I figured it'd be an easy fix.

Turns out, it was exactly my issue and the pieces had "frozen up". A quick clean out and we're back in business in under 20 minutes.