BillL
Well Known Member
I have been preparing for the cowl installation. I have the sky bolt installation and have looked at many builders sites. I plan on using the sky bolts on the cowl halves. To make the installation look good from the outside, I wanted to have line of fasteners on the cowl split line up with one fastener on the firewall.
I made an assumption (BAD) and confirmed it with two sources. I assumed that the cowl split line was parallel to the longeron along the side of the cabin. Further, that line would intersect the center of the engine crank. Will James confirmed, and a view on dwg 45 also indicates, but does not state the same. So I proceeded to finish the spinner and then located that point on the fuse along the firewall. See picture below. The plan was to locate the tabs in the lower cowl half.
The firewall Skybolt tabs have been installed. (Pict below) I began today to proceed with the upper cowl fitting. SHOCK - - the upper half does not extend down to the "centerline" . I also have the stock Vans cowl but it is only 1/2 " lower.
Oh- BTW - I called Vans - spoke to Ken this AM. In spite of the Vans drawing #45 "showing" the cowl split parallel to the longeron, it is not. Apparently it may have been but in the build of the prototype, the cowl was cast in place and then removed and sent to the supplier. Not Vans problem, but it is what it is.
It seems I have three options:
1. Respace all the tabs on the firewall.
Result, cost, delay of tabs, and issues with reaching some rivets.
2. Extend the upper cowl or have Will James make me a new one that has a longer side skirt.
Result: Issues with with a smooth extension of the side or $ of ordering and shipping a new half, IFF Will James will/can do it.
3. Locate the tabs on the upper cowl instead of the lower cowl so that the fasteners appear below the cowl split rather than above.
Result: Possible PITA in every time the cowl gets reassembled.
4. Proceed with cowl fitting, see how it goes when it gets to cutting the cowl split.
Last thought - if I do #1, or #3 then the line of fasteners will not be parallel to the longeron, it probably won't be noticeable. I checked the engine - it with in .3 degrees of being parallel to the longeron.
I made an assumption (BAD) and confirmed it with two sources. I assumed that the cowl split line was parallel to the longeron along the side of the cabin. Further, that line would intersect the center of the engine crank. Will James confirmed, and a view on dwg 45 also indicates, but does not state the same. So I proceeded to finish the spinner and then located that point on the fuse along the firewall. See picture below. The plan was to locate the tabs in the lower cowl half.
The firewall Skybolt tabs have been installed. (Pict below) I began today to proceed with the upper cowl fitting. SHOCK - - the upper half does not extend down to the "centerline" . I also have the stock Vans cowl but it is only 1/2 " lower.
Oh- BTW - I called Vans - spoke to Ken this AM. In spite of the Vans drawing #45 "showing" the cowl split parallel to the longeron, it is not. Apparently it may have been but in the build of the prototype, the cowl was cast in place and then removed and sent to the supplier. Not Vans problem, but it is what it is.
It seems I have three options:
1. Respace all the tabs on the firewall.
Result, cost, delay of tabs, and issues with reaching some rivets.
2. Extend the upper cowl or have Will James make me a new one that has a longer side skirt.
Result: Issues with with a smooth extension of the side or $ of ordering and shipping a new half, IFF Will James will/can do it.
3. Locate the tabs on the upper cowl instead of the lower cowl so that the fasteners appear below the cowl split rather than above.
Result: Possible PITA in every time the cowl gets reassembled.
4. Proceed with cowl fitting, see how it goes when it gets to cutting the cowl split.
Last thought - if I do #1, or #3 then the line of fasteners will not be parallel to the longeron, it probably won't be noticeable. I checked the engine - it with in .3 degrees of being parallel to the longeron.
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