Wood fillers are a quick fix for crevices and uneven wood surfaces. However, the question is this: can you screw into Bondo wood filler? Since wood fillers are intended to cling to wood, many newbie woodworkers wonder if the filler can also hold screws snugly. Technically, you can screw into wood fillers, but the success of this endeavor heavily relies on how well you applied the filler itself.
Below, I discussed how drilling to wood fillers work and how you can make it possible.
Is it possible to screw into Bondo wood filler?
To answer this question, it’s important to understand the characteristic of Bondo wood fillers. This product is marketed as ‘exceptionally strong’ and can rebuild damaged wood. It’s a 3M product, so it says a lot about the reliability and quality of the filler.
In terms of composition, Bondo wood filler is a mix of talc and resin. It’s more of putty than a filler since it doesn’t have wood fibers. Still, you can drill and attach a screw into it.
However, you should know that Bondo and other wood fillers don’t have the same strength as real wood. It’s tricky to drill a hole into since it cracks easily under high speeds.
Aside from that, the Bondo wood filler doesn’t have the structural strength needed to hold screws reliably, especially if it’s meant as an attachment to another wood piece. And if you subject the screw drilled into Bondo filler under force and stress, it will give in. Before you know it, you have a loose screw to repair.
Nevertheless, there’s a workaround to attach a screw into wood fillers. However, you shouldn’t expect a strong grip for long.
If you want a stronger hold, I suggest that you use epoxy wood fillers instead. Epoxy withstands harsher conditions, especially extreme weather and other outdoor elements. You can also try multipurpose fillers as these products are made to hold screws and nails tightly.
How to screw into wood fillers
As much as Bondo wood fillers have limitations when it comes to holding screws, you can still drill one into it. Here are some tips for successful drilling:
- Avoid air bubbles. During the application of the wood filler, make sure that it doesn’t have air pockets. These bubbles will compromise the hold of the screw.
- Let it dry. Once you’ve applied Bondo wood filler, you should let it dry and cure first. This would only take around 15 to 20 minutes, according to the label. However, I suggest waiting for an hour or two to ensure that the filler has hardened well.
- Prep the surface. Next, you should sand the surface and make sure that the filler blends well with the wood. You can also file any stubborn smears.
- Create a pilot hole. Even if you’re drilling self-tapping screws, you should still create a pilot hole. This will prevent the wood filler from cracking and crumbling.
Alternative to wood fillers
If you need to drill a screw on a gap or larger hole, you have the option to use dowels instead. Basically, you have to drill a hole large enough to fit a standard dowel tightly. Make sure that the drill bit matches the size of the dowel you’re using.
Once you’ve created a hole in the wood, slather the dowel with wood glue. Next, insert the dowel into the hole you created, then pound it in using a hammer. Finally, wipe the excess glue and let it dry.
After that, the patched hole is ready for drilling. Pre-drill a pilot hole on the dowel before putting the screw in. This will create a more reliable hold compared to drilling into a patch of wood filler alone.
Is wood filler as strong as real wood?
Many wood filler products are formulated with actual wood fibers. This allows the solution to adhere well to the wood material. Once dry, the wood filler will have a tough and strong consistency.
However, wood fillers don’t offer a ‘true’ structural support. After all, it’s just a dried goop of mixed ingredients. It’s not connected to the wood grain and, therefore, one of the weak spots of the wood material.
Are wood filler and wood putty the same?
Wood fillers and wood putties are two different products with unique uses.
Wood fillers are made to repair damaged wood from the inside. It also contains real wood fibers to mimic the texture and color of the wood material. This is also relatively stronger than putty since you can drill into it.
On the other hand, wood putty is used on the outside. It’s applied once the wood has been restored using wood fillers. You’re not supposed to apply wood putty inside the wood as some formulas have damaging ingredients.
Nevertheless, both wood fillers and putty are important woodworking supplies.
What can I use instead of wood fillers?
If wood fillers aren’t working for your project, you can substitute them with wood glue that’s mixed with sawdust. This has the same consistency but with a stronger hold since it’s mixed with an adhesive.
Epoxy also comes in handy whenever you need to fill wood holes, and fillers aren’t available. You can also color epoxy to match the hue of your wood material.
Does wood filler stain the same as wood?
The problem with wood fillers is it doesn’t take stain the same way as real wood. With this, the patched area of the wood material may stand out once you apply a stain coating. Also, some wood fillers will appear lighter or darker than the rest of the material once stained.
Nevertheless, you can use a pre-stain conditioner to reduce the uneven color on the filled areas. Still, this won’t produce a spotless result.
Can you use wood fillers on larger gaps?
Wood fillers will still work on large gaps. However, since you’re patching a larger area, it will be more challenging to achieve good results. You should also ensure equal application for proper curing and tough consistency.
Make sure that you choose multipurpose or exterior wood fillers as these have a more reliable hold. You should also avoid air pockets that will compromise the strength of the filler once dry.
Can you screw into Bondo wood filler? Yes, but you shouldn’t expect a topnotch hold, especially under stressful conditions. If you want to patch up and screw a specific spot in your wood piece, it’s best to use dowels and wood glue. This way, you’ll have a better ‘bite’ on the screw, and it will also last longer.
Do you have other wood filler hacks to share? Drop your secrets below in the comment section!