Making a duck tail spoiler
#1
Making a duck tail spoiler
I have had interest in a duck tail style spoiler for a long time but the cost of $300 plus shipping is too much for me, especially when I have read that several members have had "issues" with them. So I thought I would try to make a duck tail style spoiler. There are a few threads about spoiler making but many of them no longer have pictures (https://www.thirdgen.org/forums/auto...m-spoiler.html) or really go into detail so if I'm making a mistake help me out. The wood blocks that you see will be totally wrapped in fiberglass and their purpose is just to give me a skeleton for the fiberglass until it is strong enough by itself.
Since I wanted the front side of the spoiler to be flat it meant that it had to be taller in the middle and shorter on the sides because the trunk lid is curved backwards. I'm not sure if the size is too much, I do not want this looking like fast and furious. So speak up and let me know if there is a consensus that this is OK to continue or belongs more on a Honda....
Since I wanted the front side of the spoiler to be flat it meant that it had to be taller in the middle and shorter on the sides because the trunk lid is curved backwards. I'm not sure if the size is too much, I do not want this looking like fast and furious. So speak up and let me know if there is a consensus that this is OK to continue or belongs more on a Honda....
#2
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Re: Making a duck tail spoiler
Interesting and unique look...but my personal opinion is that it is too tall, especially in the center. I don't think it'd look very good when finished.
#4
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Re: Making a duck tail spoiler
I like it. little tall but. Snap a line from corner to corner, rip that off, blend it a bit and wall ah. Is there a belly/bevel to it. (side pic) I like it. Nothing on the rear quarters coming up to meet? IDK... I like it. I think you are on the right track.
-Dan
-Dan
#6
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Re: Making a duck tail spoiler
In the 3rd pic, from the right corner to the left on the back of the spoiler. make that flat and not curved. I see that your wood frame may make that a little difficult being its higher in the middle. snap a line, is a term that construction workers use, meaning hook a snap line (string with caulk) and snap a straight line and rip it off with a circle saw or what ever your liking.
Anyways, I think your on to something. Keep playing with it. what do you think the sides will look like?
-Dan
Anyways, I think your on to something. Keep playing with it. what do you think the sides will look like?
-Dan
#7
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Re: Making a duck tail spoiler
If it were me I might do some things differently, not that yours is bad, I just have a different thought process. My thoughts on the wood blocks is that it may eventually show through, especially if attached to the fiberglass. The sun will play a major factor in this especially if it's painted a dark color.
Wood expands and contracts differently than fiberglass and it may cause areas of stress/tension that may show through. To help with this I would not glue the center pieces and allow them to float (either to the fiberglass face or the dowels). One alternative if the spoiler is actually flat, is to buy some flat stock of fiberglass/composite (usually expensive). Could maybe even run 1/8” plywood instead and glass over the top of that.
Styrofoam is what I would try, but you may still need wood blocks along the bottom for stronger attachment points. Styrofoam is a lot easier to shape and make changes and/or scrap and start over again. Could even tape the foam down including the sides and then cut slots that match up with the opening between the deck lid and body. Making specially shaped sanding blocks may help as well, or hot-knifing while being careful of the fumes. The drawback with foam and the actual fiberglass is that dust from either can be very bad to breath in. Also with foam you are often stuck using epoxy resin which can be expensive Google “composite Styrofoam fiberglass” if you're not familiar with how composites get their strength and/or hard points. Many books on the subject as well.
I had thought about doing something similar and noticed the angle of the tail lights vs. the spoiler etc., and that might help you determine angle for the spoiler if you were to start over again. These cars have a lot of subtle curves that you wouldn't notice until you get into it.
Sorry to point those things out as you're pretty far along now. Just throwing ideas out there in case it helps. What you have built looks well crafted and thought out.
Wood expands and contracts differently than fiberglass and it may cause areas of stress/tension that may show through. To help with this I would not glue the center pieces and allow them to float (either to the fiberglass face or the dowels). One alternative if the spoiler is actually flat, is to buy some flat stock of fiberglass/composite (usually expensive). Could maybe even run 1/8” plywood instead and glass over the top of that.
Styrofoam is what I would try, but you may still need wood blocks along the bottom for stronger attachment points. Styrofoam is a lot easier to shape and make changes and/or scrap and start over again. Could even tape the foam down including the sides and then cut slots that match up with the opening between the deck lid and body. Making specially shaped sanding blocks may help as well, or hot-knifing while being careful of the fumes. The drawback with foam and the actual fiberglass is that dust from either can be very bad to breath in. Also with foam you are often stuck using epoxy resin which can be expensive Google “composite Styrofoam fiberglass” if you're not familiar with how composites get their strength and/or hard points. Many books on the subject as well.
I had thought about doing something similar and noticed the angle of the tail lights vs. the spoiler etc., and that might help you determine angle for the spoiler if you were to start over again. These cars have a lot of subtle curves that you wouldn't notice until you get into it.
Sorry to point those things out as you're pretty far along now. Just throwing ideas out there in case it helps. What you have built looks well crafted and thought out.
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#8
Re: Making a duck tail spoiler
In the 3rd pic, from the right corner to the left on the back of the spoiler. make that flat and not curved. I see that your wood frame may make that a little difficult being its higher in the middle. snap a line, is a term that construction workers use, meaning hook a snap line (string with caulk) and snap a straight line and rip it off with a circle saw or what ever your liking.
Anyways, I think your on to something. Keep playing with it. what do you think the sides will look like?
-Dan
Anyways, I think your on to something. Keep playing with it. what do you think the sides will look like?
-Dan
#9
Re: Making a duck tail spoiler
If it were me I might do some things differently, not that yours is bad, I just have a different thought process. My thoughts on the wood blocks is that it may eventually show through, especially if attached to the fiberglass. The sun will play a major factor in this especially if it's painted a dark color.
Wood expands and contracts differently than fiberglass and it may cause areas of stress/tension that may show through. To help with this I would not glue the center pieces and allow them to float (either to the fiberglass face or the dowels). One alternative if the spoiler is actually flat, is to buy some flat stock of fiberglass/composite (usually expensive). Could maybe even run 1/8” plywood instead and glass over the top of that.
Styrofoam is what I would try, but you may still need wood blocks along the bottom for stronger attachment points. Styrofoam is a lot easier to shape and make changes and/or scrap and start over again. Could even tape the foam down including the sides and then cut slots that match up with the opening between the deck lid and body. Making specially shaped sanding blocks may help as well, or hot-knifing while being careful of the fumes. The drawback with foam and the actual fiberglass is that dust from either can be very bad to breath in. Also with foam you are often stuck using epoxy resin which can be expensive Google “composite Styrofoam fiberglass” if you're not familiar with how composites get their strength and/or hard points. Many books on the subject as well.
I had thought about doing something similar and noticed the angle of the tail lights vs. the spoiler etc., and that might help you determine angle for the spoiler if you were to start over again. These cars have a lot of subtle curves that you wouldn't notice until you get into it.
Sorry to point those things out as you're pretty far along now. Just throwing ideas out there in case it helps. What you have built looks well crafted and thought out.
Wood expands and contracts differently than fiberglass and it may cause areas of stress/tension that may show through. To help with this I would not glue the center pieces and allow them to float (either to the fiberglass face or the dowels). One alternative if the spoiler is actually flat, is to buy some flat stock of fiberglass/composite (usually expensive). Could maybe even run 1/8” plywood instead and glass over the top of that.
Styrofoam is what I would try, but you may still need wood blocks along the bottom for stronger attachment points. Styrofoam is a lot easier to shape and make changes and/or scrap and start over again. Could even tape the foam down including the sides and then cut slots that match up with the opening between the deck lid and body. Making specially shaped sanding blocks may help as well, or hot-knifing while being careful of the fumes. The drawback with foam and the actual fiberglass is that dust from either can be very bad to breath in. Also with foam you are often stuck using epoxy resin which can be expensive Google “composite Styrofoam fiberglass” if you're not familiar with how composites get their strength and/or hard points. Many books on the subject as well.
I had thought about doing something similar and noticed the angle of the tail lights vs. the spoiler etc., and that might help you determine angle for the spoiler if you were to start over again. These cars have a lot of subtle curves that you wouldn't notice until you get into it.
Sorry to point those things out as you're pretty far along now. Just throwing ideas out there in case it helps. What you have built looks well crafted and thought out.
#10
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Re: Making a duck tail spoiler
Oh, because of the compound curves? Yes I guess that could be difficult.
I can think of 2-3 ways offhand but it would probably be more intensive than what you're doing now.
I can think of 2-3 ways offhand but it would probably be more intensive than what you're doing now.
#12
Re: Making a duck tail spoiler
Took some of your advice and cut a bit off the top, it is now shorter and fairly flat at 7" tall. I had to remake the back contour pieces. Now how does it look?
I think that the Hawks spoiler is 5" or 6" tall, can't recall.
I think that the Hawks spoiler is 5" or 6" tall, can't recall.
#13
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Re: Making a duck tail spoiler
I commend you on your efforts. I think that looks better than the rounded whale tail you initially envisioned. This car has so many Edges that rounded parts generally don't flow with the rest of the vehicle. Is it straight ? I cannot tell from this pic if its straight or not. Maybe I didn't see it in the post, but are you going to make the matching pieces that attach to the body on the rear Panel left/right (like hawks) ?
#15
Re: Making a duck tail spoiler
This project has taken a back seat to all the engine bay work lately. The spoiler is straight on the top and not curved. I will make the side pieces. I have considered making it out of steel. Always an option. Really wanting a duck bill I stead of the 91-92 wing. Those wings are decorational and these are at least arguably effective.
#16
Re: Making a duck tail spoiler
Actually, the better way to do this is, use drill rod to make a wire frame. Drill rod is easily formed to make the contour of your choice and is able to be welded. Then use flat bar stock to create the mounts and place a through bolt welded in place to mount to hatch. Wrap with fleece and coat with resin. A couple of coats of fleece/resin will give plenty of material to make fine adjustments, then do usual body prep and paint.
#17
Re: Making a duck tail spoiler
I found with the long pieces that when the fleece is stretched and taught it will still sag once resin is applied unless you use lots of supports or start with thin coats on the front and then once hardened soak the back. For flat pieces I prefer the way I did it by making the flat section on the floor or table so one side is perfectly flat and smooth with no sanding required.
#19
Re: Making a duck tail spoiler
I found with the long pieces that when the fleece is stretched and taught it will still sag once resin is applied unless you use lots of supports or start with thin coats on the front and then once hardened soak the back. For flat pieces I prefer the way I did it by making the flat section on the floor or table so one side is perfectly flat and smooth with no sanding required.
If you're concerned about it sagging, place a layer of chicken wire over the wire frame. It is easily contoured also, and can add support between the frame.
#20
Re: Making a duck tail spoiler
You have a lot of supports now. Replacing what you have with drill rod, will not only make it stronger, and lighter, but also not have any expansion from moisture wicking in. If the wire frame is constructed properly, it won't sag when the fleece is applied.
If you're concerned about it sagging, place a layer of chicken wire over the wire frame. It is easily contoured also, and can add support between the frame.
If you're concerned about it sagging, place a layer of chicken wire over the wire frame. It is easily contoured also, and can add support between the frame.
#21
Re: Making a duck tail spoiler
Nothing really new here. Just wanted to add that the materials and your time (depending how much of it you have) quickly add up. At this point I have a little less than $100 in materials and lots of time.
I may try buying a stock 3 piece spoiler from a junk yard and elongating it with some similar material. I'm not sure if it's a urethane, abs or regular plastic.
I may try buying a stock 3 piece spoiler from a junk yard and elongating it with some similar material. I'm not sure if it's a urethane, abs or regular plastic.
#22
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Re: Making a duck tail spoiler
I have had interest in a duck tail style spoiler for a long time but the cost of $300 plus shipping is too much for me, especially when I have read that several members have had "issues" with them. So I thought I would try to make a duck tail style spoiler. There are a few threads about spoiler making but many of them no longer have pictures (https://www.thirdgen.org/forums/auto...m-spoiler.html) or really go into detail so if I'm making a mistake help me out. The wood blocks that you see will be totally wrapped in fiberglass and their purpose is just to give me a skeleton for the fiberglass until it is strong enough by itself.
Since I wanted the front side of the spoiler to be flat it meant that it had to be taller in the middle and shorter on the sides because the trunk lid is curved backwards. I'm not sure if the size is too much, I do not want this looking like fast and furious. So speak up and let me know if there is a consensus that this is OK to continue or belongs more on a Honda....
Since I wanted the front side of the spoiler to be flat it meant that it had to be taller in the middle and shorter on the sides because the trunk lid is curved backwards. I'm not sure if the size is too much, I do not want this looking like fast and furious. So speak up and let me know if there is a consensus that this is OK to continue or belongs more on a Honda....
#25
Re: Making a duck tail spoiler
That looks great, I would be interested in knowing how you did it. I haven't worked on the spoiler for a while. I want to get the body and panel in paint before the heat of desert summer arrives so I put all other projects on hold. Again though, I couldn't get the leading surface flat when I used foam and tried to shape it. Only thing I could think of was a table saw...
#26
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Re: Making a duck tail spoiler
Tibo,
JohnyIROC (TGO MOD - Ontario section) has a similiar 5" duck spoiler on his dark red IROC.
Perhaps you could PM him to see how he made his
Profile link
\https://www.thirdgen.org/forums/member.php?u=3911
JohnyIROC (TGO MOD - Ontario section) has a similiar 5" duck spoiler on his dark red IROC.
Perhaps you could PM him to see how he made his
Profile link
\https://www.thirdgen.org/forums/member.php?u=3911
#27
Re: Making a duck tail spoiler
I had seen his spoiler before but hadn't contacted him. There is also another member that used a second gen spoiler and just cut and glued the center/trunk/hatch section for the appropriate width that also looked good. I might try buying a stock junkyard spoiler and lengthening it also.
#30
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Re: Making a duck tail spoiler
Could try making it in wood then taking a mold from it in glass, and using that to make a glass spoiler. Shapers that build surfboards use the foam and epoxy resin process, probably lots of board making vids on youtube if you want to go that route. Aircraft back before 1935 mostly used fabric over wood frame construction, light and strong, the fabric was doped, which meant coated with a early form of epoxy resin to make it air tight and stiff.
I did work for Glastron boats for a while and I can tell you that in fiberglass boat construction plywood and wood blocks are commonly used to reinforce glass hulls without any problems.
I did work for Glastron boats for a while and I can tell you that in fiberglass boat construction plywood and wood blocks are commonly used to reinforce glass hulls without any problems.
Last edited by mmadden55; 02-14-2016 at 08:08 AM.
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Re: Making a duck tail spoiler
If you aren't using a mold , you will never get it flat and smooth by building up alone. You have to build up beyond what you want , then sand down to flat and smooth.
If you make a mold, you build the blank with foam , wood, whatever, it doesn't matter, then sand and fill smooth, then cast a mold from that. Then you cast the part from the mold and the outside is the shape you want.
If you make a mold, you build the blank with foam , wood, whatever, it doesn't matter, then sand and fill smooth, then cast a mold from that. Then you cast the part from the mold and the outside is the shape you want.
#32
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Re: Making a duck tail spoiler
Could look into rigid shaped hotwiring the foam along the length. Might be able to get the compound curves that way. Be careful of the type of foam used and toxic fumes.
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Re: Making a duck tail spoiler
I like that it's tall in the center. Looks very Nascar-ish, which I love
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