IH Hood Video

Several other posts have documented the work I performed on my 1993 International Truck Hood. I also took some video and recently got it all put together and posted on Youtube. Hopefully you can learn a couple of things.

The SMC hood was ground in preparation of work, and then I used epoxy and fiberglass to complete the work and restore the structure and shape back to original for this truck hood.

Repairing the Inner Fender

One of my recent projects involved the repair of a 1993 International Medium-Duty truck hood made from SMC. There were several areas needing attention, and one of them was the driver’s side inner fender. This piece had formerly been attached with button-head pop rivets. This design is common to composites, and allows for easy replacement of the separate fiberglass pieces. The pop rivets had come loose over time, allowed to move around, and cause severe damage to the extent that the riveting flange was broken off. My only solution was to bond the two pieces together.

Material Fatigue in the corner

Material Fatigue in the corner

The loose panel flexed so much and for so long that it fatigued the material and failed in the corner of the inner fender next to the attachment to the rest of the hood. To repair this, I removed the area with the rivets, ground down the surfaces of both pieces on both sides, and reattached them with fiberglass and epoxy resin.

Prepared glass and resin

Prepared glass and resin

I wanted to place epoxy and fiberglass on both sides of the repair area to ensure a good, solid bond that would hold very well.

Epoxy Resin and Fiberglass applied

Epoxy Resin and Fiberglass applied

After the area was prepared, I applied epoxy resin to the surface to ensure good adhesion. I had a low spot that was a gap, so I mixed some microfiber and epoxy to make a paste and fill this gap. A stronger bond is produced when the fiberglass is not spanning an open gap between the two pieces. I placed two layers of 3oz Chopped Strand Mat over the paste and worked the air out to make a nice consistent repair. I then ground down the surface to make a nice-looking, consistent repair.

Rear inner fender

The rear of the inner fender had similar problems. A hole had emerged in the black SMC piece. I ground down both surfaces and placed some fiberglass across the area to bond it together.

IH Hood Repair– Passenger Corner

One of the repairs on my International Hood was for the passenger corner. This portion of the hood was damaged before I got it, and was COMPLETELY MISSING!

Time, effort, epoxy, and fiberglass, allowed me to successfully completed the repair. This SMC hood will be repaired as good as new!

Damaged area to be repaired

Damaged area to be repaired

The hood was placed upside to allow for work

access. The repair area had several cracks and breakage areas. The repair began with surface preparation.

Surface Preparation on the repair area

Surface Preparation on the repair area

I used a grinding disc to remove material on the front and back side of the repair to scarf the repair into the large area. Good surface preparation gives us a clean area that can hold a bond and create a transition area. I also drilled some holes in the end of the cracks to stop their propagation.

The back side was prepared too

The back side was prepared too

The back side was prepared for repair by grinding the surface to allow for good bonding by the epoxy resin and glass reinforcement.

Beginning to add material

Beginning to add material

I started to add epoxy and fiberglass back onto the fender. I had to gradually move back out to where the existing fender used to be. I worked both sides bit by bit and allowed it to start curing before adding more.

Getting the shape back

Getting the shape back

I actually went a bit beyond the shape I needed. This allowed me to get the surface planes in the right spot, and later return and trim back the proper hood edge.

Back side getting rebuilt

Back side getting rebuilt

The back side of the repair also got transitioned into the hood and out to meet the front repair area.

Grinding the repair

Grinding the repair

After most of the rebuilding was complete, some grinding got it back into shape to allow an evaluation of the repair progress.

Grinding on the back

Grinding on the back

The back side was cleaned up as well, getting the appropriate part thickness back to where it was originally intended. A nice transitioned surface was created, and all sharp edges were removed.

Bodyfiller for cosmetics

Bodyfiller for cosmetics

I used some bodyfiller to smooth the repair and restore the cosmetics of the hood. I could also have used epoxy, and it would have bonded better. Polyester bodyfiller is less expensive, easier to apply, and easier to sand. I smoothed the surface and feathered it back into the surrounding area to allow for a consistant surface.

Application of Primer-Surfacer

Application of Primer-Surfacer

Urethane Primer-Surfacer is applied to the whole area to allow for removing the sanding/grinding scratches and preparing the surface for paint application.

The repair is complete, and the hood looks back like it was original. This repair, and many others, can be detected with some investigation of the back side of the repair area. This will be a very durable repair and will last as long as the rest of the composite body panel.

Working with Bondo

Commonly referred to by the trade name of “Bondo,” polyester body filler is used by autobody shops to achieve cosmetic repairs on automobiles.  It is relatively inexpensive, easy to work with, and achieves good results when used properly.  It is basically polyester resin that is highly filled to create a thick paste which can be turned into a solid with the addtion of a hardener.

I have been using autobody filler since age 14, and am finally getting good at it!  Just kidding.  It is more art than science, and practice makes perfect.  Basically, a surface needs to be properly prepared to achieve good adhesion.  Then the filler is applied after being mixed with hardener, and allowed to cure afterwords.  Some fillers can be sanded as soon as 20 minutes after application.

Basic setup and tools

Basic setup and tools

The basic setup is a working board surface to mix the bondo and hardener.  The mixed material is applied with a squeegee or putty knife to fill in low areas.  They also aid in cleanup, along with some paint thinner to clean the tools.

Hardener added

Hardener added

Mixing the read moreThe Ups And Downs Of Fruit Machine Games Slots are often considered to be the easiest casino games to play. hardener starts the application window from where the material goes from liquid to solid.  The hardener is a peroxide paste that directly affects cure time along with temperature.  Too little hardener can also cause poor physical strength characteristics along with difficult sanding properties.

Uniformly mixed

Uniformly mixed

The hardener must be uniformly mixed before it is applied.  This prevents lots of problems down the road.

Applied to surface

Applied to surface

The body filler can be applied generic cialis from india bying with putty knives or squeegees to achieve the desired affect.  This polyester bodyfiller will shrink during cure, so filling high is typical.  The flip side is that all of the high spots must be sanded back down, which is wasting filler and time, so it is a fine line to walk.

Working with body filler can be frustrating for the beginner who must practice lots of patience.  There are many important aspects that must be followed, just like all composites materials processes.  Autobody filler requires proper surface preparation, mixing and metering of materials, and attention to details in order to avoid future problems.

A couple of other practices I recommend is to always wear a dust mask, keep the body filler dry, and only apply bondo over sanded bondo.  Some like to just build layers without sanding the lows, and this can lead to adhesion problems.

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