View Full Version : How to mold in your Danko spoiler

07-26-2008, 02:17 AM
Things you will need:
Danko spoiler- I went for the inverted shaved 1.25"
Neoprene Gloves
Air DA sander
3/4" masking tape (yellow kind)
4 Tubes of SEM Problem Plastic Repair
Adhesive caulking gun air or manual
80 grit DA sand paper
24 Roloc grinder wheel
Air Grinder to fit roloc wheel
40 grit DA sand paper
Fiberglass cloth 6 1/2" wide strips
Eye protection
Bondo spreader
Sem plastic cleaner or windex
Paint stick to place sand paper on to sand edges and body lines
SEM no swell plastic body repair glaze

I started with mine already srewed in place in the middle, get the grill where you want it and place four screws with washers underneath the lip to hold in place.

I also recommend molding in the middle first to ensure the correct fit. You can always sand down the edges on both sides if they over hang a little.

Here is a picture of mine already molded into place but I will show you how to do the sides. You will be an expert after reading this... I hope!!


First make sure when you are starting to mount the spoiler it is sanded on the inside lip, the area on the fascia it will adhere to (allow about 2 inches of area to be completely sanded) make sure no paint is present and you are seeing the black of the bumper. Use the 24 grit roloc with an air grinder to scuff these areas.

Scuff the inside lip of the spoiler, the outside lip about 1 inch from crease of spoiler with the 24 grit roloc. It is very important to ensure the fiberglass and plastic have been completely scuffed..

Here is a picture of the sanded fascia and spoiler lip.


Once you have the spoiler ready and know where you want to mount it use the SEM Problem plastic repair adhesive.


Hold the spoiler in place and make sure the gap between the spoiler is as minimal as possible. You will want to make sure the SEM problem plastic repair adhesive gets into the gap and covers both sides of the spoiler.

You will have about 4 minutes working time with this stuff, and it gets very hot to the touch after a few minutes until it dries. Please use gloves.

After you have spread the SEM problem plastic repair adhesive onto the spoiler squeeze the spoiler into place, you will not need to clamp it just hold it steady until it dries. You have about 3-4 minutes to get it where you want it. You will also want to spread out the SEM problem plastic repair adhesive with your fingers to try and fill the gap where the spoiler meets the fascia body line.

Here is a picture of the first coat after it has been spread.

After you have spread the SEM problem plastic repair adhesive and it has dried wait about 10 minutes and sand down the big chunks that you did not smooth out with the 24 grit roloc, once you have knocked the plastic repair down you can sand it down further with a DA and 80 grit. Try just to smooth it out and not take off everything you just put down.


Once sanded smooth and all of the shiny look is gone on the problem plastic repair. Get your Fiberglass strips ready (1/2" strips) You will want to straddle the line of where the spoiler and fascia meet up.

Lay a large amount of the SEM problem plastic repair adhesive, enough to cover the fiberglass strips when you lay them on the problem plastic repair adhesive. The object is to lay the bead starting at the top of the edge of the where the spoiler meets the fascia and let it drip down.


Once you have layed the bead down, quickly place the fiberglass cloth strips down and push them into the bead to secure them. You will want to straddle half of the spoiler and half of the fascia. Make sure the fiberglass cloth is as flat as possible and the SEM problem plastic repair adhesive covers as much as the cloth as you can.

Sand between each coat of the SEM problem plastic repair adhesive. You only will have to lay one strip of the fiberglass cloth down. The rest of the coats will be the SEM problem plastic repair adhesive. You will want to keep applying coats until the fiberglass is completely covered up. Remember to always sand between each coat.


Keep sanding and applying the SEM problem plastic repair until you get this effect. You will still need to use the paint stick with stick on 80 grit to get your lines crisp.

Here are a few pictures of how it should look like when sanded correctly, I still need to do some detail sanding and smoothing the body lines of the spoiler but you get the idea. Also there is no SEM no swell body panel plastic repair on this part yet.


Once you have achieved the desired lines, apply the SEM no swell plastic body panel repair glaze. Do not use Bondo because it will not flex like the SEM product is designed to.


Spread this on after you have sanded the spoiler area down with 80 grit and a DA.

You will need to apply a few coats, it spreads just like bondo.
Sand inbetween coats of this stuff and final sand with 600 wet sand paper then prime.

11-23-2009, 01:12 AM
nice writeup!!

11-23-2009, 09:03 AM
nice and informative

11-23-2009, 09:49 AM
about how long does this process take, from start to ready-to-paint?

11-23-2009, 09:07 PM
Green beans!

11-23-2009, 09:24 PM
I would assume that it depends on what type of material you get, how heavy you put it on, and how good you are at sanding/prep work. I purchased some stuff today to finish my front bumper cover and it comes in 1, 5, 20, or 90 min. forms........it usually says how long you have to let it sit before you paint it. To be safe I always give stuff at least 24hrs before I paint over it.

this one says you have 5 mins of open time, 7 min of work time, 15 min clamp time and 45 sanding time.

11-23-2009, 09:51 PM
Are you leaving the fog lights off?

11-23-2009, 09:55 PM

11-25-2009, 02:05 AM
daaaaaaaahm!! Anyone got extra pics of the fabricated body parts on this?? seams in roofline?? what he does for brakelights??

11-25-2009, 02:06 AM
daaaaaaaahm!! Anyone got extra pics of the fabricated body parts on this?? seams in roofline?? what he does for brakelights??

Isn't it for the Chin Spoiler ????

02-06-2010, 03:19 PM

09-03-2011, 11:33 PM
omg u r a monster!