OK, we didn’t solve the exhaust plating question but managed to put it on hold for now so, next problem, my cowling doesn’t fit !!
The 0-320, the cowling and the engine mount came from a flying AcroSport 1 purchased firewall forward by me. One would “assume” everything should fit ??
I don’t know what cowling I have, someone will recognize the design. I built my firewall to plans. All the sheetmetal, stainless firewall and formers are primed and nut plated,
I do not want to throw it all away and start over. That means I have to make the cowling fit what I have. I would guess the firewall on the previous AcroSport was built to fit this cowling which is why it isn’t fitting a plans built firewall.
This cowling is not in the best of shape. It has been modified with blisters and air intakes before so I am already going to eliminate a couple blisters and fabricate a new intake.
It also has a couple small cracks that need repair. The bottom half of the cowling fits the firewall quite well, it is the top that needs to be taller.
You can see this in the photo’s, the top lacks a good 3/4” on each side of center of being high enough.
Only as a last resort do I want to make a plug and layup a new cowling.
It seems to me that my easiest out is to modify the existing cowling.
I have come up with 3 separate ideas;
Idea #1) split the top down the centerline front to back, set it on the firewall and glass in the pie shaped piece that results
Idea #2) Install the cowling as best I can then fill in from the top of the firewall to the spinner and glass it then cut out the old cowling from the inside.
This will make the outside look good but the inside will be really bad
Idea #3) Fill in from firewall to spinner as per idea #2 then layup a complete new upper cowling using the old cowling as a mold. If I do that, I may as well make the modifications needed to the lower cowling and use it for a mold and layup a new lower cowling.
#3 may be my best bet even though I dread doing it. Thats why I am here - for some good advice or positive reinforcement as I know several of you guys have modified or built from scratch your own cowlings. Because of the cowling size I will need to learn something about vacuum forming
My plan for this winter was to get everything covered and ready to paint in the spring - - not gonna happen is it
So, questions I can think of - and please, bring up answers to the questions I haven’t thought of - -
1) If I use idea #3 will I have to make a female mold from the cowling then make a male from that to get it to fit my firewall ?
2) How many layers of glass will it take to be strong enough ?
3) Should there be any reinforcements / stiffeners (like 1/8” or 1/16” thick foam or ??? ) in the large areas ?
4) Should metal strips be imbedded in the glass where the fasteners will go. ?
What forum threads would help me through this, books to read, on-line info ? I've already read Chris Murley's threads until I have worn the print off the pages but there are a lot of basic unanswered questions this fiberglass newbie has
I have experience fiberglassing kayaks but I have never used carbon. Also, kayaks are one full piece of cloth, no joints, no overlaps, very little sanding except smoothing fill coats.
And, if I end up making a complete new cowling - - those two intake holes look absolutely gigantic to me. Can they be modified at all to look better and still cool the engine
I also don't like the bluntness of the nose but I may live with that. A guy can only solve so many problems at a time ya know.
And you guys thought you didn’t have much to talk about over the Holidays
I am looking forward to some enlightening conversation
Thank you and the best Holidays to y'all and your families.
P.S. My exhaust will not fit inside this cowling either, I will need a new one so the plating question will be getting revisited - - just trying to tie everything together here . . . . try to keep up
The 0-320, the cowling and the engine mount came from a flying AcroSport 1 purchased firewall forward by me. One would “assume” everything should fit ??
I don’t know what cowling I have, someone will recognize the design. I built my firewall to plans. All the sheetmetal, stainless firewall and formers are primed and nut plated,
I do not want to throw it all away and start over. That means I have to make the cowling fit what I have. I would guess the firewall on the previous AcroSport was built to fit this cowling which is why it isn’t fitting a plans built firewall.
This cowling is not in the best of shape. It has been modified with blisters and air intakes before so I am already going to eliminate a couple blisters and fabricate a new intake.
It also has a couple small cracks that need repair. The bottom half of the cowling fits the firewall quite well, it is the top that needs to be taller.
You can see this in the photo’s, the top lacks a good 3/4” on each side of center of being high enough.
Only as a last resort do I want to make a plug and layup a new cowling.
It seems to me that my easiest out is to modify the existing cowling.I have come up with 3 separate ideas;
Idea #1) split the top down the centerline front to back, set it on the firewall and glass in the pie shaped piece that results
Idea #2) Install the cowling as best I can then fill in from the top of the firewall to the spinner and glass it then cut out the old cowling from the inside.
This will make the outside look good but the inside will be really bad
Idea #3) Fill in from firewall to spinner as per idea #2 then layup a complete new upper cowling using the old cowling as a mold. If I do that, I may as well make the modifications needed to the lower cowling and use it for a mold and layup a new lower cowling.
#3 may be my best bet even though I dread doing it. Thats why I am here - for some good advice or positive reinforcement as I know several of you guys have modified or built from scratch your own cowlings. Because of the cowling size I will need to learn something about vacuum forming
My plan for this winter was to get everything covered and ready to paint in the spring - - not gonna happen is it
So, questions I can think of - and please, bring up answers to the questions I haven’t thought of - -
1) If I use idea #3 will I have to make a female mold from the cowling then make a male from that to get it to fit my firewall ?
2) How many layers of glass will it take to be strong enough ?
3) Should there be any reinforcements / stiffeners (like 1/8” or 1/16” thick foam or ??? ) in the large areas ?
4) Should metal strips be imbedded in the glass where the fasteners will go. ?
What forum threads would help me through this, books to read, on-line info ? I've already read Chris Murley's threads until I have worn the print off the pages but there are a lot of basic unanswered questions this fiberglass newbie has
I have experience fiberglassing kayaks but I have never used carbon. Also, kayaks are one full piece of cloth, no joints, no overlaps, very little sanding except smoothing fill coats.
And, if I end up making a complete new cowling - - those two intake holes look absolutely gigantic to me. Can they be modified at all to look better and still cool the engine
I also don't like the bluntness of the nose but I may live with that. A guy can only solve so many problems at a time ya know.
And you guys thought you didn’t have much to talk about over the Holidays
I am looking forward to some enlightening conversation
Thank you and the best Holidays to y'all and your families.
P.S. My exhaust will not fit inside this cowling either, I will need a new one so the plating question will be getting revisited - - just trying to tie everything together here . . . . try to keep up
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