The bridge plate on the Kay K22 looks to be pretty chewed up. It appears to be spruce, which is a bit unusual for a bridge plate. Most makers use a hardwood such as maple or rosewood.
I'm applying the lessons learned in previous bridge plate removals. First, I cut a piece of sponge to fit the plate itself. It's a rectangle. Here I'm eyeballing it against where the plate actually is underneath the top. Or, at least where I can best guesstimate it.
I made the sponge not too wet - it's wet but not dripping. Then I sat it on the bridge plate with the body upside down. Then I went outside to shovel snow.
When I came back, the plate was wet. Not drenched - I didn't want to get the wood around it wet - but defintely wet. Since heat and water will loosen hide glue, this should be a good thing.
I was able to fit both of the irons onto the bridge plate. I heated them in a cast iron pan up to about 400 degrees F. You need to be careful when placing them - it's easy to get a minor burn if you touch them.
I did a couple rounds of heating with the irons - I let them sit on the plate for about 5 minutes at a time. I could feel the top getting fairly warm on the outside, so I knew they were transmitting heat.
This was of some use during the Martin removal, but it turned out to be gold for this one!
And finally you see the great Italian palette knife I used for the fingerboard removal.
I worked in from the ends with the thin knife, and when I got into into the joints, I went in with the bigger knives. You can see how I wedged the front edge of the plate up with the Italian knife (far right). About 2/3 of the plate is up off the top - you can see that if you study the picture.
With two of the knives levering the plate up, I got the chisel under the other end. I drove it into the seam, and then gently used it as a lever to pull the plate up off the top. That chisel is great, because it doesn't flex like the other knives. Because Kay used hide glue on it orignally, it all came up fairly easily. Definitely the easiest bridge plate removal I've done.
Note the outside screw holes for the old bridge in both the top and the plate. I'm going to plug those holes in the top.
Also, see how badly chewed-up the string holes are. This is a good example of why not to use spruce as a bridge plate.
Next up I'm going to make a new maple plate and glue it in. The maple has a much sharper tone than the spruce, so I'm hoping it will help the overall tone in terms of treble clarity and note definition. We shall see.