Acoustic Guitar Construction

Ok, this is one of the simplest of steps to concepts to some/most and just eludes me....

What is my reference point to know when the rim is flat? I clamp it in the mold and just sand the top of the rim, how do I know it's even all the way around? If the rim is not referenced to "something" I will just be sanding the same error or worse.

I need an ah-ha moment. I will settle for a Doh! as well.

This step is just a very light couple of passes, you're really not trying to remove a lot of material. You could run a white pencil mark around the rim and just sand enough to that the mark is removed and you would be fine. I just run a flat stick with sandpaper attached to it, forward and back a couple of times, not pressing down hard.

Thanks for the info...

This step could be called "truing the top edge of the rim" the most important part to take into consideration is that you what to start your sloping operation (next step) with this edge not only flat but also 90 degrees to the rim especially at the neck block This is why I have the Martin factory process video and the sanding machine pictures and explanations used as part of the instruction package. the KMG process is exactly the same in principle and subsequent end results.

Dave is correct it does not take much to clean up that edge. Remember when you assembled the blocks, the top edge was indeed a reference point -- level and flat against the work-board all you've done is flipped it over -- so yes it could be set at the same height above the mold and it would be level - but not yet smooth which is what you are trying to accomplish.

kencierp wrote:This step could be called "truing the top edge of the rim" the most important part to take into consideration is that you what to start your sloping operation (next step) with this edge not only flat but also 90 degrees to the rim especially at the neck block This is why I have the Martin factory process video and the sanding machine pictures and explanations used as part of the instruction package. the KMG process is exactly the same in principle and subsequent end results.

Dave is correct it does not take much to clean up that edge. Remember when you assembled the blocks, the top edge was indeed a reference point -- level and flat against the work-board all you've done is flipped it over -- so yes it could be set at the same height above the mold and it would be level - but not yet smooth which is what you are trying to accomplish.

Thanks Ken, I will be sure to pay attention to the 90 degree to rim angle as well as the point about the block.