Table of Contents
How long does Bondo take to fully cure?
Bondo mixed to the color swatch will begin to cure in less than 10 minutes at room temperature. Too much hardener in a warm environment will reduce working time, but too little in a cool environment can result in maddeningly long curing times. A heat lamp can speed curing in colder weather.
How long do you wait to sand Bondo?
Generally, in a matter if a few minutes it will start to harden and get rubbery. At that point, you can carve it up with a utility knife, a hand planer or a bondo rasp. Just make sure you leave enough to do a final sanding, usually within 10 to 15 minutes you can start sanding it.
Do you have to sand Bondo right away?
Once the Bondo cures, it’s time to sand. Power sanders are OK to break the surface and knock down any high spots, but hand sanding with the body contour is the best way forward.
How long before you can sand body filler?
There are two schools of thought on when to sand filler. If you are doing general bodywork, leveling wavy panels, fixing small dings, etc, then wait until the filler is fully cured, about 20-30 minutes.
How long can you leave Bondo unpainted?
Between life and work, the longest time period the bondo would go Unpainted would be about 2-3 weeks.
Can you sand Bondo the next day?
Choose between Bondo Fiberglass Resins, Bondo Fiberglass Repair Kits or Bondo Body Fillers. Bondo Fiberglass Resins and Repair Kits are 100 percent waterproof. Bondo Ultimate can be applied directly over sanded and cured primer and paint. This filler remains easy to sand for days after the application.
Why is my Bondo still tacky?
It could just be the skim on the top that stays sticky. Some lower quality fillers don’t have the additives required to stop that from happening. Try sanding it, if it remains soft and clogs your paper after that first top coat has been removed then you need to take all off.
What grit sandpaper do I use for Bondo?
Directions for Use If grinding is needed use a 3M™ 36 or 40 grinding disc followed by 3M™ 80 grit sandpaper if no grinding is required, sand the surface with 3M™ 80 grit sandpaper to remove all primer, paint and rust 1 to 2 inches beyond the outer edges of damaged area. Remove all dust created from sanding.
Do you prime before Bondo?
Read the thread “Metal to Metal”. Bondo over time absorbs water causing rust to form underneath. It can also shrink over time causing paint to bubble or peel off. If used..the metal must be primed first.
Can Bondo go over primer?
A Bondo type of filler, is used for thicker applications, shaping and the like, all the rest is more like primer, the trick for all fillers is to be completely DRY before any type of paint or even primer is put over it, as then it may never dry completely and it then will draw moisture, when it is completely DRY, it Jan 13, 2009.
When should I use Bondo?
Bondo is an automotive body filler, often used for car and household repairs. You can use Bondo to fill in small dings and smooth out warped panels in a car body. Before you begin applying Bondo, make sure to sand down the paint, replace any rusted metal, and mask off any areas that don’t need filler.
Should you primer before body filler?
Do not proceed to Primer Filler stage until filled area is even. Adding body filler AFTER primer filler should be avoided to prevent possible adhesion, staining and shrinkage concerns.
What is the best surface to mix Bondo on?
Cut a thick piece of cardboard about 6 by 6 inches (15.24 cm by 15.24 cm). Alternatively, you can mix it on particle board or buy an inexpensive pad of disposable plastic sheets to mix the Bondo. Open the can and mix the Bondo with a stir stick if there is a layer of liquid on top.
What primer do I use over body filler?
Urethane primer (2K) Urethane primer is the most common primer used in auto body and restoration by far. It has good solids and fills well. It is easy to sand and can provide you with a perfect body when blocked properly. Care should be taken when applying it as to not use too much.
Can you paint over body filler?
Fillers and putties will normally work OK over properly sanded (80-180 grit) cured OEM paint. However, with so many different types of aftermarket paint available (lacquer, enamel, urethane, water-based). We recommend that all paint be removed where filler is to be applied.”Nov 3, 2012.
Can I wet sand Bondo?
Don’t wet sand filler. Filler is too absorbant and you can have problems getting it dry plus you could cause moisture to wick through to the metal or weaken the bond between the filler and the substrate.
Do I need to paint over bondo?
You should use a “direct to metal” (DTM) primer to help top coats stick to the metal but it’s not needed under body filler most of the time. Once the metal is primed then you can apply a “filler primer” (2K) to help hide scratches and minor surface irregularities.
Do you have to paint over bondo?
NO PRIMER! It SUCKS IN WATER, and will cause RUST and let moisture get into the bondo! Paint it with krylon, or some surplus TOPCOAT, but NEVER primer.
Can you add color to bondo?
You can tint BONDO with paint tint. Use small amount to start, just a few drops, mixed in before you add the hardener, to get the color you want. I have used this for years, long before it hit the stores for damaged wood repair!Oct 20, 2015.
