How hard is epoxy wood filler?

I've asked quite a few questions regarding prop building, as to try and get back to my project. Major issue is the VOC of body filler and fiberglass resin. However, I think I found a soultion to it.

I was curious as to how hard epoxy wood filler is once cured. Is it something that (god forbid) if coated onto something, and said something is dropped, will the epoxy be damaged? How hard is it work with (ie, can I heat it up to make it 'thinner')?

Thanks in advance! 

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Burf3 years ago

Epoxy wood putty has, as designed by the manufacturer, about the same resistance to damage as does the wood its applied to. Because it is made to be worked with regular carpenter tools, it will scratch or dent just like wood.

I've never tried to use it in applications other than as wood filler but in the process of cleaning up dollops dropped and cured on concrete, it sort of crumbles from a hard hammer blow but only the area directly impacted by the hammer. It will crack and break if severely flexed but overall, I'd say its pretty tough and durable.

I wouldn't try to change its consistency by any method not suggested by the


DoctorWoo (author)  Burf3 years ago

I kinda figured that [it would be close to wood once cured]. If you were to probably paint it (if it can be painted) would that assist a bit in the resisting of being dented?

As for a hard hammer blow: do you think that if I were to drop a helmet coated in the epoxy from a height of about 5 feet, would that be enough to cause a spiderweb crack? Or would it only crack on the impact point?

Burf DoctorWoo3 years ago

Actually, I doubt a 5 foot drop on a hard, smooth surface would cause little more than a few small scuff marks. if at all. On a hard, rough surface (like gravelled asphalt) you might get a few small dents from the gravel. I don't think it would crack at all unless the helmet shell flexes underneath.

Paint will probably do very little to protect the putty.

DoctorWoo (author)  Burf3 years ago

Fantastic! Thank you very much.

iceng3 years ago

GOD does not forbid epoxy wood filler !

The devil tries to make makes filler epoxy to expand at a different rate then the wood you are filling as ambient temperature changes.

DoctorWoo (author)  iceng3 years ago

Just to make God or the Devil wining? That is, does wood filler epoxy shrink/expand while curing?

iceng DoctorWoo3 years ago

I seem to remember the amount of hardener added could alter the curing to match the wood expansion properties

( so trial and error experience was necessary ) .

Then a great many epoxies have a wee bit curl and shrinkage after 30 years.


Free will being taken way too literally by uneducated barbarians seems to be helping hell a lot lately.

caarntedd3 years ago

It is very tough and should resist being dropped. It is quite thin and workable before it starts to set (which is quite a short length of time). It seems to set more quickly in warmer weather so heat probably won't help. Mix small amounts to build up large areas to prevent a large batch setting before you can use it.

rickharris3 years ago

Epoxy wood filler is relativly cheap - Buy some and experiment.