This 6 meter 6 element SSB yagi was designed and optimized for best feed match using 50.125MHz as the center frequency which is in the SSB portion of the 6 meter band. The older "Quick Yagi" program was used in its design.

According to the program, it has a gain of 11.06dBi with a front to back (F/B) ratio of 30.12dB on a boom length of 17 3/4 feet with 1/2 inch elements using a standard direct feed dipole driven element insulated from the boom.
The QY4 design program indicated that the VSWR is flat at the design frequency of 50.125 (1:1), and at 49.49mhz, 1.47 : 1 and 2.22 : 1 at 50.752mhz.
It should be noted that the numbers quoted above came from within the perfect world of the computer program and not from the real world that an antenna exists in.

No matching device should be required as it was designed to be direct fed with 50 ohm coax, but due to variations in your construction practices, some adjustment of the driven element may be needed or us a gamma match with non-split (not insulated from boom) solid dipole driven element and tune for best SWR.
When checking SWR, place antenna with reflector on the ground and prop yagi straight up at a ninety degree angle to earth....use low power to check SRW.....adjust match or length of driven element as required and recheck. Repeat procedure until lowest SWR is obtained and mount yagi on your mast, pole, tower, etc in a horizontal position relative to the ground for 6 meter SSB operation.
The SWR in the final operating position may vary slightly but not enough to worry about.
The measurements on the picture below may be very hard to obtain perfectly, but don't worry too much about them! Try to get them as close as possible using whatever construction practices and genius you can find. Round them off to next highest or lowest number and forget about them.

Total boom length = 17 3/4 feet (1 inch metal boom)
(Refer to Drawing Above)
Get your lengths as close as possible


Perfection is best......... but hard to get in the homebrew environment!

The driven element (dipole) shown in the inset in the drawing is insulated from the boom which is metal, by the homemade non-conducting bracket which you must fabricate. Heavy Plexiglass works fine as long as it is thick enough to support the driven elements (one on each side). Other materials may be used to construct the insulator as long as they insulate both halfs of the dirven element from the boom.

The two halves of the total driven element length can be attached to the insulator using muffler type clamps, u bolts, several large wire ties or what ever your gray matter can come up with as long as the elements can not move by outside forces and do not touch the boom after final installation.

The other elements of the antenna should be installed thru the boom but if this is not possible for you, just mount them at the required spacing using your genius. The final pattern may be slightly off center from the boom by a degree or two but us it anyway.
The idea is to have FUN and experiment!
The conductors from the feedline (50 ohm coax) are attached as you would any dipole. Center to one side, shield to the other using whatever arrangement of nuts and bolts you may have. Seal all connections, coax end and antenna elements from mother nature!
If you decide to use a gamma match instead of this type of mounting arrangement for the dipole, you won't have to worry about the mounting bracket for the dipole but then you will have to decide on a way to mount the gamma match.
You can design your own gamma match for this antenna by using a separate program that comes with the Quick Yagi antenna design software. Get the free complete download here!  Note!!!!This is a zip file!  "Quick Yagi" will only operate on Windows XP or some earlier versions of windows. Download and unzip the program into a folder of your choice if using Windows XP or earlier versions then unzip it and use "Set Up" file to get started. You can try it on other versions later than XP but it may not work! Make sure you read the help files and documentation within the program.

This project was designed to give you a starting point in getting on the air on 6 meter SSB fun with a respectible signal using just a stock radio and it should increase your effective radiated power near 9 times (plus or minus a few % for construction errorrrrrrssssss!

It is also a good idea to use an "Ugly Balun" or other 1:1 balun capable of 6 meter operation near the feed point to help eliminate rf on the outside of the coax!

EXPERIMENT! EXPERIMENT! EXPERIMENT!
This editor once built a 6 element yagi for the middle of the 2 meter band using discarded aluminum sections for the elements that were "U" shaped from old junk flouresant light fixtures and attached them to a 1 inch square boom, 16 inches apart for each and the standard dipole formula 468/freqmhz was used for the driven element fed with a homebrew gamma match. 5% was added for the reflector length and each director was shortened 5% shorter each, progressing to the end of the boom!
SWR was checked as above and was less than 2 to1 to start but was lowered a bit, down to about 1.5 to 1 and put up on a 16 foot mast with rotor and it worked great!

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