Mazda Rotary Club

General => General Technical => Topic started by: Arnie_O on November 29, 2011, 06:30:25 PM

Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:30:25 PM
Well this is now posted everywhare else so i guess some of you guys may find this usefull.

Well somone hit my car the other night and left some nice work for me to do.
here is the damage i was greated by in the morning.

(http://a4.sphotos.ak.fbcdn.net/hphotos-ak-ash4/380312_2796106741333_1218398916_33301653_897224140_n.jpg)

(http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/s720x720/379714_2796106261321_1218398916_33301652_1547319738_n.jpg)

(http://a8.sphotos.ak.fbcdn.net/hphotos-ak-ash4/s720x720/390163_2796105821310_1218398916_33301651_2037111024_n.jpg)

So  after having to repair my bumper less than 6 months ago i find i am  having to do it again... this time with the knowledge that i know what i  am doing.

Well till it comes to painting it that it.

So this is more of a rough guide than a full on step by step DIY... it should give you the right idea though.

Remember  when working with Fiberglass, cover up, wear a mask and goggles and  some latex gloves are a good idea too. spceially when it comes to mixing  up the resin.
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:31:01 PM
Right bit of an update while i am waiting for the fiberglass to go off.

I removed the bumper to be greated by some nice damage to the rear though the back does not look as bad as the front

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-1.jpg)
There  seems to be another small crack towards the centre however this is not  visable from the front so i plan to just clean the back up and lay fomr  fiberglass in there, to strengthen it up.


I then stripped the bumper of all its grills and brackets in the area i am going to repair.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-2.jpg)


The  next thing your going to need to do it drill some holes at the end of  all the cracks to stop them going any further, this is where is starts  to look worst before it looks better.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-3.jpg)


Once  thats done your going to need to start cutting out all the broken and  damaged fibers. i prefer to use a small dremel drinding wheel for this  part and start by "dishing" the front out along where all the cracks  are. It does not show it in the picture but look close enough and you  can trace the lines where the cracks are going.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-4.jpg)


After  this your going to need to get heavy with it and cut some gaping holes  in the material to get fid of any left over material thats broken.  
As  you can see i have started "dishing" out the the inside of the mouth  area too in this picture, this will eventually be done on all of the  cuts and holes.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-5.jpg)


This  picture shows where i have started to clean up the back of the other  bit of the damage. What you may sometimes find is that the fibre will  delaminate from itself and while you think you have cut it all out there  is areas where the fibers have split in parallel with the surface of  the bumper. These really do need to be cut out dont be shy with that  dremel
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-6.jpg)

Another Image of the front being cleaned up.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-7.jpg)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:31:49 PM
The Next strp is to start prepping it for fiberglassing and resin... so  stop all the resin dripping out the gaps when i apply it I have covered  all the holes with "Velocity Red" Gaffa tape.
this also helps keep  everything in line and you will see in some later pictures that I use  some metal bar with some carpet tape to line everything back up again.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-8.jpg)


some  scrap ally clamped along the back edge of the mouth helps keep  everything in line. I have alsy masked off most of the bumper with take  and plastic to prevent unwanted resin dripping on parts that wont need  painting again.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-9.jpg)


This  image shows where i have keyed the surface up with an angle grinder,  this gets rid of loose dirt and fibers it also helps remove the paint  from the inside arounf the area we are going to be repairing.
Once i  have cleaned the surface i also added some shallow scoring in a criss  cross manner to help the new resin and glass to adhere better.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-10.jpg)

I had to skip the various stages of glassing it out due to having fingers covered in rapidly hardening resin.
Your  going to want some throw away tin trays for this stage as your going to  need to soak your matting in the resin before applying it to the  damaged area.
Cut your fiberglass matting to the sizes your going to need before you start mixing the resin and hardner.
Mix your resin to the correct ratios on the packaging, I have used plastic padding here as its what i have used before.
Once  your resin is mixed start by brushing on some resin with some of the  resin with a sheap paint brush, your going to need to work fast so plan  in advance where your going to place your matting.
You want to start  with some large pieces over the damaged area, then work out from there  overlapping then where you can to help build strength. once you have  laid your wet matting on to the area your doing to need to add more  resin to the back to stick it in plate.

DO NOT USE A BRUSHING ACTION
This  will just pull your fibers apart... add resin to the back with a  stippeling action making sure you push the wet matting in to any corners  and cracks.

Keep building up layers as long as your previous  layers are still wet, make sure you do not lift any of the fibers up and  breate air pockets in your repair. if you do and it sets hard then you  will need to sand these out and add more resin and matting once  everything is hard (this takes more time)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-11.jpg)

All is left to do then is allow your repair to set.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-12.jpg)

Heat heps the mixture of resin and hardner set quicker so here i am using a halogen heater.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-13.jpg)

Once  its all set hard next Ill remove all the coverings from the front and  start work on clraning it up ready for bodyfiller and eventually  painting.

Watch this space
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:32:39 PM
More Updates

So while the first lot of Body Filler is setting under the halogen heater its update time.

After  the Fiberglass had set hard i removed all of the masking and Gaffa tape  from the front of the bumper, The heat has left some of the glue stuck  to the paintwork and some of the tape has also been grabbed by the Resin  as it set, this it no big problem as the stuff stuck to the resin will  be removes in the next step.

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-14.jpg)

You  can see from the pictures that there are areas that the Matting has not  gotten right down in to, These could leave air pockets when we wpply  the body filler if left as is.
These will need to be ground out with the dremel and a grinding wheel, leaving a smooth surface to apply the filler in to.
There are several areas like this on the repair.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-15.jpg)


the  next picture shows what it looks like once we start cleaning up the  area ready for siller. this will help smooth out any highs and wharp  edges or "caves" between the damaged area and the new matting applied to  the repair.
You can also see from the pictures the cracking of the surface paint caused by the fool that couldnt drive
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-16.jpg)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-17.jpg)

These are most of the tools we are gonna need to finish this part of the job.
>Some form of Body Filler (preferably easy to sand)
>Hardner (usually comes with the filler but a good idea to get extra)
>Random Orbital Sander
>80grit, 120grit and 240grit Sanding discs
>Body Filler Applicators (these ones where silverline and made from springy steal so follow the contours better)
>Somthing flat to mix your bodyfiller on (I use a bit of cut up posterborad)
>Air Duster (attached to compressor)
>Brake Cleaner (not pictures)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-18.jpg)

I  started to Sand out the areas to be filled using the orbital sander and  some 80grit discs, this cuts through the paint and srein quite easily,  you need to smooth any really high ridges out that are not in line with  your finished surface

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-19.jpg)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-20.jpg)

Just working it out a little more
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-21.jpg)

Next your going to want to clean the area up of all the dust and old glue this is where the Brake cleaner comes it.
Start  by blowing as much of the dust ect away with the air duster attachment  then give the area a good dose of brake cleaner, then sipe clean with a  dlean Lint free cloth.
the brake cleaner should help remove any glue thats stuck to the paint in places.
Once its clean give it one more blast of brake cleaner then dry it all off with the compressed air from the air duster.

TIME FOR BODYFILLER (THE SNOT)

This  is never a one step process annoyingly, start by mixing a small amount  of the body filler putty with the correct ratio of hardner mis well as  per the instructions.
Now as with the resin earlier your going to need to work fast but have a plan of attack.

Start  by applying a small amount to the deep areas and making sure its pushed  well in. then you can add extra to smooth the surface, your probably  going to get a fed low spots but this can be sorted with another  application of filler later on.

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-22.jpg)

Just keep working with whatever size applicator card suite the area.
when  finishing the surface work in slot smooth motions in one direction  making sure your applicatior is wide enough to bridge the gaps your  filling and can also follow the contours of the undamaged body.

When  it some to corners this is where it takes come time, its generally a  case of applying some to fill the area than danding it back once hard  then applying more till you can build up enough filler to then shape  yourcorner of curve with sand paper ect.

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-23.jpg)
The  above picture shows the first application of filler fo the leading edge  of the mouth ill nees to sand this back then build up more to achive  the desired shape.

More to come
Watch this space
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:34:00 PM
Yes Folks Its Update Time Again.

While the second dose of body filler sets lets fill you in on what your missing.

Well  now that the Filler has set, it dont take long, maybe 20 minutes. its  just a matter of hitting it with the orbital sander, i am still using  the 80grit discs will it comes to finishing, at this stage its just  about filling the dips in the repair then danding everything back flat  and smooth again.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-24.jpg)



The  lower secton is a little more tricky as its a far more complex shape  however its much the same, its just all about sanding away all the  ridges and excess filler till its getting towards the shape you need.
As  you can see from the picture there where a few ait pickets that got  trapped in the first layer, however i am quite lucky as they where  mostly trapped in excess filler that requires removing anyway.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-25.jpg)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-30.jpg)



And  a little more work this time with some 320grit paper on a block of  wood. just taking as much of the excess off as possible, and returning  the body back in to its correct shape.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-26.jpg)

I  had a few sharp ridges of filler in places these I had to gently sand  doen with 320grit by hand (finger) no block, I also used the Orbital  sander in plaved that needed feathering out to a smooth edge to meet  with the original surface.

Clean off the excess dust from sanding ready for more filler.

Next  up its time to mix up a little more filler, for the second skim coat,  The idea now is to start filling in the gaps left by sanding the first  coat and try to build up any edges so you can shape them later on.

With  the plastic padding your mixing ration is roughly a gold ball size blob  of putty to a pea size blob of hardner (the more hardner you add the  quicker it will go off)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-27.jpg)


Again  with the applicators start to fill the low spots, with this coar your  going to try and build up a little extra thickness so hopefully you can  sand it back to a nice smooth finish, dont worry if you need to add  further body filler, just keep doing it till your happy with the finish.

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-28.jpg)

When  the filer starts to pull like in this picture ist starting to set, so  you have not got to leave it to go off sand it back and add some more if  needed

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-29.jpg)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:34:59 PM
Ok Last Update of the day

So the second skim coats set and i have started sanding it down.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-31.jpg)


Not far off the right shape for the bottom edge nowm just a couple of small low spots to fill again
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-32.jpg)


Flatting  the top part of the damage out with the orbital sander here... and now  feeling with my finders for any small high or low spots that will need  sanding smooth
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-33.jpg)

Not far away now.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-34.jpg)

now  its time to clean everything up again, for a third and hopefully last  coat of filler. there is a small low spot i missed with the second coar  at the top point of the high damaged ares this is quite deep to needs  filler for sure.
(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-35.jpg)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-36.jpg)

I  am going to leave this to go off overnight... not realy because it  needs to but because its late and i have been on this for the best poart  of the day.

Stay tuned for more updates Kids


Third Coat of Filler gone on now after rubbing the second one down
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on November 29, 2011, 06:36:53 PM
Final Mini Update for now as its too dark to get any pictures of the "finished article"

Well this morning I got to rubbing the last layer of body filler down and smoothing things out ready for *cough* Paint *cough* I have decided that with brands just round the corner than ill just wrap it in some Vinyl to protect it and possibly make it look a little more respectable. Once i am ready for paint ill remove the Vinyl and key everything up ready for painting.

anyway here are a couple of pictures of the final job.

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-37.jpg)

(http://www.arnie_o.talktalk.net/CarPictures/Tutorials/BumperRapairMk2/BumperRepairMk2-38.jpg)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: grinder on November 29, 2011, 06:58:28 PM
nice write up - very informative :D

Shame it happened in the first place though
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Lacey on November 29, 2011, 06:59:40 PM
Awesome job you\'ve done! Love the process pics, very informative on proper techniques if you\'re new to it :)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Erdin on November 30, 2011, 12:47:13 AM
Nice job iv always wanted to see a step by step of this.

thanks for that.
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: goldk28611 on November 30, 2011, 11:09:41 AM
good work on the write up and work done - bookmarked as am sure this will happen to me sometime soon!
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: L18M on November 30, 2011, 12:36:19 PM
really good info! can this be made a sticky pls :)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on December 01, 2011, 11:42:41 AM
Well Thanks for the comments but i must say i was amazed that no one had done anything similer on here before.. considering how modified most FD\'s are and the age of the club.

Glad i could add some original content to a forum that i have taken so much from.
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: Arnie_O on December 05, 2011, 05:17:23 PM
And finally the result before painting is this


(http://a5.sphotos.ak.fbcdn.net/hphotos-ak-snc7/390050_2853884025729_1218398916_33322350_2015553698_n.jpg)
Title: How to Repair your Fiberglass bumper when some anus drives in to it!!!
Post by: samfc3s on December 07, 2011, 01:46:55 PM
wowww......nice write up as everyone said, may be handy for my plastic car.....