nywoodwizard

I Built a mantle a few months ago and used some i think elmers wood fill it actually expanded out of the screw holes,i only used a few screws,thank god,its all biscuts and finish nails. i can kick myself in the ass for using this crap,i'll have to dig it out and use something else.just to think i'm the one always telling people not to get cheap,i don't meet my own standards,i hang my head in shame

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Scott Young

for what you are going to use it for i use dap plastic wood. it is acetone based and cures very fast.

Richard

mh readypatch

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Rich

Paul B

I plug screw holes.

ibsocal

automotive type spot putty two component dries quick sands smooth.

nywoodwizard

I considered that but it was only a few holes and it was being painted,i think it had something to do with the heat of the fireplace.

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Workaholic

I use crawfords putty. Was this mdf that you used?

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Sean

Workaholic

Automotive bondo is not a great thing to use if you are using it in new construction. Had a trim guy swear by how great it is, he applied it, sanded it. And we primed it and painted it. Then when we go to do final, it was all cracked out. Causing us a lot of extra work. IMO the only place for it in residential construction is for metal doors.

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Sean

ibsocal

you might could have experinced seperation with the bondage stuff if not allowed propper cure time prior to sanding,i have not yet and have gone through over 20 gal of the stuff on manny types of substrates .again i use automotive "spot putty" two component type with excellent results for small fill jobs like the kind you had issues with.

Teetorbilt

Wood expands and contracts depending upon humidity and temperature. Polyester products (Bondo) are ridgid and shrink over their lifetime (undetermined).

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ibsocal

good point.just about every thing on this earth expands and contracts including you, even steel.polyester has plastic in it so it bonds and expands and contracts with any given substrate.3" steel plate on a aircraft carrier flight deck expands 1"-3" in length during flight opps coated with epoxy non skid coatings which are more rigid than polyesters and i have never seen a coating failure due to expansion contraction.have you ever seen a part of a fender fall off where it had bondo,me never.even tiajuana bondo holds up.so i thinks it could have been improperly applied over dust dirt oils debris which could have caused a adhesion/coating failure

nywoodwizard

It was MDF , But using mdf isn't uncommon for fireplace mantles,and a relativly stable wood once acclamated,it only happened on the screw holes though,not the finish nail holes ,the mystery deepens .So i may have to blame it on a number of things,the heat caused wood expansion and forced the filler out,pretty consistently too, there all up about a 1/6,the screw itself absorbs heat also, and may have also contributed,or just crappy filler.Live and learn i suppose.

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