Comment

Comment by Marcel S. Mikulec on June 9, 2012 at 6:14pm

Thanks Jerry.  With your help, and the other posts I now feel confident with my rivet locations.  J

Comment by Jerry Latimer on June 8, 2012 at 7:02pm

The technique I used building my HDS was to layout where the end rivets would be.  I would then measure this distance (X).  I would then divide X by the pitch the plans called out.  In your case the pitch was 20, so I would divide X by 20.  This would give a number such as 6.3.  It was never a whole number.  I would then round the 6.3 up to 7 and divide X by 7.  This would give me the pitch I would use.  It was always slightly less than than what the plans called. 

     The fan is much easier and I probably should have purchase one, but I got good at this and it didn't take long to calculate.

     Most of my 40 pitch rivets were actually 38.5.  During the rudder workshop Roger was the person that showed me the technique.  You always want your actual pitch to be less than the specified pitch, never bigger.

    Hope this isn't too confusing.  (the XL/650 builders miss out on a lot of fun)

    Jerry Latimer

    175 hours and no rivet problems.

Comment by Marcel S. Mikulec on June 8, 2012 at 7:12am

Yes, I like the fan. I wish I would of bought a bigger one. Acquiring tools is my second hobby. :)

Comment by Ronald Steele on June 7, 2012 at 2:05pm

If you view the stated pitch as the maximum spacing, and as a guideline, the width of the finished rivet as the minimum, you should be OK.  The great thing about the rivet fan is that you set to the specified pitch, then squeeze it down till the ends are where you want, and you are at a good working pitch.  If the run is longer than your fan, you can usually just set use the fan on the some of the last rivets and set the first ones at the nominal pitch.  Your eye will have a very hard time telling the difference between a 40mm and 35mm pitch all set in a nice straight line.  I lost my fan for a few weeks and had to use a calculator and ruler and it was no fun at all.

Comment by Marcel S. Mikulec on June 6, 2012 at 8:10pm

Thank you guys.  Your advice was really helpful.

Comment by Jerry VanNuil on June 6, 2012 at 5:26pm

Marcel, I took a piece of .025 aluminum that is 36" x 1" and marked with a sharpie 40mm increments all the way across the 1" dimension and them marked in between the 40mm marks half way across which is 20mm spacing. I mark the first rivet hole 10mm from the edge on both ends of the row, then I place this make shift scale between the first holes and split the difference if the spacing doesn't work out exactly. This asures all the rivets are the same distance except the first two on each end of the row. If the first two are a little closer together it doesn't matter. It's simple, cheep and can be made in a few minutes. Also it lays flat on curves surfaces making it easier to mark.

Comment by Dave Gardea on June 6, 2012 at 6:46am

Hello Marcel,

That is unfortunate you did not receive the help needed when you called Zenith. I would not hesitate to call them again in the future, though, if you need support. In the meantime, you may want to refer to page 7 of the Zenair construction standards at the link below:

http://www.zenithair.com/pdf-doc/zenair%20construction%20standards%...

It's important to adher to the recommended minimum edge distance of 10mm for holes near the edge of a part. Beyond that do your best to maintain the rivet pitch specified, but it's OK to finish a row with less than the specified pitch when the final hole is on an edge with the required minimum 10mm edge distance. I also highly recommend purchasing a rivet fan for laying out and marking your holes along a line per the specified pitch. It's a great investment and saves time.

Regards,

Dave