Blogging Fatso!

[David L]

Here are the pictures of the final result. I'm quite satisfied with the results, The backplate has a nice contour to it, when I lay it back on the radius disc it has an almost vacuum effect.

[David L]

I would like to know where to store the completed backplate. when I did the glue-up, the RH was right at about 50%, I didn't have to do anything to achieve this RH factor, just some nice dry weather (dry for south Louisiana anyway) we're having right now. Humidity inside the house right now is at 54%. I don't have any kind of control of the RH in the shop and as the weather changes, so will the RH, more than likely it will be going up, way up, which is typical for my geogpaphic location. I haven't monitered the RH fluctuations inside the house but I'm quite sure that they will not be as drastic as out in the shop. I still have lots of things to do before I close the box, thus needing the backplate i.e. brace the top plate, radius the rim, glue in lining/kerfing, radius the rim again with kerfing installed, etc... It seems like storing inside the house would be the more logical choice, but my logic is sometimes, well, just downright illogical. Thoughts anyone?

Thanks a lot,
David L

[David L]

I can't remember if anyone has ever talked about whether or not they radius the rim prior to installing the lining. I just got done radiusing the back side of the rim with my new handy dandy KMG contour fixture. I worked the blocks down flush with the rest of the rim first and then started to contour the whole rim. I noticed that I had a low spot just above the waist on the upper bout (about 3/16" or maybe 1/4"). So round and round I went to work the rim down til even with the low spot. When I was done I realized that the blocks were now standing proud of the rest of the rim. Even though I was careful to continually work in half circles, the blocks sanded down at a lower rate than the rest of the rim, my best guess is because there is more surface area there. Due to my one track mind, focussing on that low spot, I was unable to see this happening at the time. Now when I look back, it was one of those "duh" things. This was definitely operator error and in no way equiptment failure! No big deal though, all I had to do was concentrate the sanding bar at those two locations, and since they are 180 degrees from each other, I was able to bring them both down level with no problem. I'm glad I radiused the rim without the lining because I would have removed the same amount of lining material as well to get the low spot out. I know it may not have been much, but 3/16" or more, I'm not comfortable with.

David L

[Kevin Sjostrand]

David,
You did okay. Normally you would contour the rims, glue in the kerfing, then radius. If they are pre-contoured for you, then just make sure you check the level plain across the two rims before you do this, and make corrections like you did before gluing in the kerfing.
Now with what you've done, make sure and re-radius after gluing in the kerfing about a 1/32" proud of the rims, and you will be good to go.

Kevin

[David L]

Thanks guys, yeah Tony, I've got the back inside the house right now and that is where the guitar is going to live if the finished project comes out decent, if not then it will find itself a nice cozy home in the fireplace, but it won't "live" there for very long (haha).

David L

[David L]

Alas, woe is me! Yes, I'm throwing myself a pitty party and all are invited. The old humidity bug-a-boos. We are having some high RH here right now, around 70%. I'm waiting for the next cool front to move down from up north with dry air to do the bracing on the top plate, so I figured that while I was waiting, I would go ahead and do something that I thought wouldn't be so RH sensitive, like slope the top side of the rim for the neck angle set, well, I was having problems leveling the rim in my contour fixture and after chasing a gap around and trying everything I could think of (without success), I finally broke down and emailed Ken for help and after consulting back and forth a couple of times we figured (well really Ken did) that the high RH has my contour fixture going wacko on me, the spindle base is skewed and the top plate of the fixture is warping some. After getting a proper diagnosis, I set out find the cure. I turned on the AC in the shop and the RH is at 62% after running AC for about 20 hrs. I was hoping for better results. The problem is the shop is not insulated and worse of all it has no ceiling, the heat and moisture constantly dump down into the shop. I do have some options, I can move these RH sensitive operations into the house, which has it's own set of problems but doable. I know I'm going to have to be more proactive with trying to "control" (more like minimize) the RH in the shop with de-humidifiers and other things, the problem is, that in the summer our RH consistently runs in the high 90's. I'm right down here on the Gulf of Mexico and our prevailing southerly winds constantly bathe us with warm, moist Gulf air. We will still get a few dry cool fronts through here before summer sets in, and I should be able to brace up the top and even get the box closed up when the RH window opens.
I just took a break and made another RH reading in the shop and it is actually down to about 55%. The RH seems to fluctuate through out day being at the lowest around mid-afternoon, However I'm not going to run out there and try to do something like brace up the top as I know the RH will be rising within an hour or so. I do think that I will try to see if I can do something with that rim. I'm going to scope it out, Maybe I will, Maybe not. I have decided that I'm not going to make a move if everything is not right and I'm not talking about only RH issues. I know (in the long run) I will be fighting this RH issue, but I'm not a quitter and I will prevail in the end as I have decided that I'm going to do watever it takes to do this right. Anyway, thanks for listening to me boo-hoo!

David L

[David L]

I actually found something that I could do that is not humidity critical (at least I don't think it is). I cut that goofy looking tongue thingie off of the neck block. I did it with the rim in the mold mounted to the contour fixture. I used a coping saw and cleaned it up with a file and sanding block.

[David L]

Almost done with the lining, one more half of the back side of the rim to go and then I will be ready to do a final radiusing of the rim. Still waiting on the humidity to break so I can brace the top, five day forecast doesn't show a front coming down, I'm impatiently waiting

David L

[David L]

I just sloped the top for the neck angle and it seems to me that I went too far. I don't really know as I have never done this before, but it just doesn't look right. with the level on the lower bout and waist the gap is about 3/16" pushing 1/4", however with the flat sanding stick set down the centerline on the spindle, the gap is only about 1/16". is the level somehow giving me a false reading or something to the effect that it's not a proper way to measure this angle?

David L

[johnnparchem]

What size radius did you use and what is the level on?