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Gluing CF Into X Braces and Cutting X Brace Joint
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Author:  Chris Paulick [ Mon Aug 31, 2009 6:16 am ]
Post subject:  Gluing CF Into X Braces and Cutting X Brace Joint
viewtopic.php?f=10117&t=23633&start=0
Author:  johno [ Mon Aug 31, 2009 7:48 am ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
Hi Chris,

Nice tutorial and video

A couple of comments/questions.

Remember the dust created from carbon fiber can be nasty. I know your dado cut was really small, but I assume there will be additional shaping of the brace that could cause a lot of carbon dust. Just be careful.

Are you building "true" flat-tops are will there be a radius on the bottom of the x-brace ... if so how do you add that in after the fact? If you are using a spinning sanding dish to add the radius, just remember to be careful with the carbon fiber dust.

All dust is bad, but I guess the carbon dust is extra bad
Author:  TonyKarol [ Mon Aug 31, 2009 12:23 pm ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
A couple things to add .. nice vid BTW ....

You need tpo make sure and mark where along the X brace you want the notch to be cut .. its usually NOT in the centre of the braces. Since I cut mine after the bottom has been radiused, you also need to make sure that one brace is radius up, the other is radius down (DAMHIK) .. from years back !!!!

The other thing to be aware of is that once the angle for the fingerjoint is cut into the X, depending on how you put the two pieces togther, you get one of the two angles with your long sides of the X .. you CAN set your mitre gauge to the smaller angle, and then put the X brace together and get the complimentary angle .... try it !!!
Author:  Chris Paulick [ Mon Aug 31, 2009 12:55 pm ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
Good point on the dust as I found out that if you get some on your hands it feels the same as fiber glass with the itching. So it's probably simular to fiberglass in that respect.
I ran by the fact that my sled stop at the end which is at the same angle of cut is set at the distance of my joint. It's something like 7-7/16" and is setup for my guitar and isn't centered. My braces are also cut in series from the billet and I arrange them when slotting to have the grain the same. And do flip one over for the cut so that the are the same when put together. So thanks for pointing that out Tony. It's hard to get everything in on a 10 minute video. That's why I welcome discussion on them.
Also it has been recommended to me by Mario Proulx that if using CF in your braces to use a 24 teeth 7 1/4" Diablo blade and nibble the joint out as the CF is hard on blades and this way you can save the Dado blades. Better to dull the $9 blade.
I'm not to clear on what you are saying about the angle? But I know if you measure off the wrong way it won't work. I guess you couldn't see the patch I made in the sled then. oops_sign :)
Author:  TonyKarol [ Mon Aug 31, 2009 3:47 pm ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
I too used to nibble away at a notch to get the joint to fit .. I have a better idea - use two blades, and add spacers (I use an old soundhole cutout and the LV spacer set) until the cut is right on. No guessing at all, perfect every time. Make a note of what spacers you use for a given X thickness.

the angle .. notice how when you cut one angle, say 98 degrees, the other one is right next to it when you hold up the X together which adds up to 180 .... so if you cut a 82 degree angle, you get a 98 anyway, its just that the lengths may not be right. Anytime you cut two angled notches, they can go together in two different ways .. only one is the one you want though.

In order to cut the desired angle, simply set your mitre gauge to the angle subtracting 90 from the total .. ie, for 98 degrees, set the gauge to 8 degrees off square (which is where your other 90 is). I made the mistake (once, a while back !!!!) assuming that well, I want 8 degrees, and I am cutting two pieces, so I need 4 degrees per piece .. wrong - doesnt work that way !!!! These things happen when you figure most of this out for yourself - no teacher !!!
Author:  Chris Paulick [ Mon Aug 31, 2009 4:48 pm ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
Interesting in that I pulled the braces apart and revolved the braces 90 degrees and when fitted back together it formed the other angle. So I guess I didn't need to re do the sled after all, just put the braces together the other way. oops_sign oops_sign :D
Live and learn. It hadn't dawned on me that it would go together two ways. If I were left handed I probably would have put it together the correct way at first. :lol:
Like you said about learning these things for yourself.
Author:  Chris Paulick [ Mon Aug 31, 2009 5:20 pm ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
I had someone suggest to me that I edit out any mistakes I make in my videos. I told a friend that I don't mind showing any mistakes I make as I think people learn by seeing them and then know why not to do whatever I did. I learned a lot about running rigid conduit from the first electrician I worked with by seeing all the screwups he made. :D
If there is anyone here who hasn't made a mistake then let me know who you are? I want to hear about how you can walk on water too. :P
Author:  Andy Birko [ Wed Sep 02, 2009 6:57 am ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
Chris Paulick wrote:
I had someone suggest to me that I edit out any mistakes I make in my videos. I told a friend that I don't mind showing any mistakes I make as I think people learn by seeing them and then know why not to do whatever I did.


I sort of agree that you should edit out the mistakes although even better would be to show the right way and then you could edit away to the mistake as it's probably common.

The reason I think so as these videos are posted as "tutorials" which usually means that this is a proven and vetted way of doing something. If no mention of the mistake is made in the video, how does one know it's a mistake until they do it and it ends up bad?
Author:  Chris Paulick [ Wed Sep 02, 2009 8:15 am ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
The mistakes are obvious and miner. There aren't any that effect that outcome. For instance, On bending a plexi side. I bent the side and it wasn't forward enough so I had to raise the waist press and pull the sandwich forward and then screw the vise down again. I could have edited that out but why? Although it was a plexi side it could have been a wood side. It shows how to correct the mistake if made.
Author:  Andy Birko [ Wed Sep 02, 2009 8:35 am ]
Post subject:  Re: Gluing CF Into X Braces and Cutting X Brace Joint
Chris Paulick wrote:
The mistakes are obvious and miner. There aren't any that effect that outcome. For instance, On bending a plexi side. I bent the side and it wasn't forward enough so I had to raise the waist press and pull the sandwich forward and then screw the vise down again. I could have edited that out but why? Although it was a plexi side it could have been a wood side. It shows how to correct the mistake if made.


That's totally cool. I thought you meant mistakes that you made that weren't fixed in the video. Showing a mistake and a correction in the same video is more helpful than just showing the right way.
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