Epoxy For Filling Gaps

[Woodworking_Hobby]

Has anyone used epoxy to fill gaps on a project where aesthetic is not critical and just want to fill the void?  There are no structural issues with the joint it is just not fully flush. I was looking at using West Systems G/Flex 650, 650 with 403 fillers, or just using the pre-thickened 665.  I was looking at the thickened and fillers as I did not want the epoxy to run down the face or out of the joint.  Epoxy is a new world for me and just wondering if anyone had done something similar.  

 

[Just Bob]

I use thickeners all the time.  It just depends on what I am doing, and how I am going to use it,  that determines which thickener I a going to use'  If I am going have exposed joints, but not worried about strength, I will used very  fine saw dust from the project that I am working one.  This is the most common use for me.  If I need a thickener that wont weaken the bond I use the West System 404.  It is a silica based thickener that allows you to adjust the thickness without affecting the bond.  but it is pure white I will very much show on an imperfect joint.   Over the years I have use, used coffee grounds, saw dust,  one of my kids even wanted me to use egg shells for her project, that even worked.

[Woodworking_Hobby]

1 hour ago, Just Bob said:

I use thickeners all the time.  It just depends on what I am doing, and how I am going to use it,  that determines which thickener I a going to use'  If I am going have exposed joints, but not worried about strength, I will used very  fine saw dust from the project that I am working one.  This is the most common use for me.  If I need a thickener that wont weaken the bond I use the West System 404.  It is a silica based thickener that allows you to adjust the thickness without affecting the bond.  but it is pure white I will very much show on an imperfect joint.   Over the years I have use, used coffee grounds, saw dust,  one of my kids even wanted me to use egg shells for her project, that even worked.

Thanks for the info!  When you use saw dust does that “dry out” the epoxy?  I was just not sure how the epoxy would react and if it would look “lumpy” or still dry flat. 

[Tom King]

I use a number of different epoxies, for all sorts of purposes, including West Systems.

I used the silica filler for decades, but always respect it enough not to breathe any of the very fine dust.  You Don't want silica in your lungs.

My current favorite is the High Density filler, mainly because it doesn't hang in the air like the very lightweight stuff does.  It's harder to sand, but not really that much harder.

Working with epoxy carries its own skill set.  I use thicker than the thin disposable gloves, and put something down on the floor to catch the inevitable spills.  Have Acetone on hand for cleanup of wet stuff.

Babysit it, and catch it before it sets up hard, but after it's past the sticky stage, and you can clean up excess, and close to finish shape it easily with sharp chisels.

Don't do any sanding of it without Really Good breathing protection.  I use Supplied Air.

[wtnhighlander]

I've always used wood dust or the like as epoxy filler. Takes a LOT to even make the epoxy close to dry. You can mix it to the consistency of modeling clay, and epoxy may still leak out, especially the slow set varieties. Like Tom said, baby sit.

[Just Bob]

22 hours ago, Woodworking_Hobby said:

hanks for the info!  When you use saw dust does that “dry out” the epoxy?  I was just not sure how the epoxy would react and if it would look “lumpy” or still dry flat. 

I have never had an issue with drying or weakening a joint.  I suppose it could  happen, but let common sense drive and it shouldnt.

[Woodworking_Hobby]

On 9/29/2021 at 12:05 PM, Just Bob said:

I use thickeners all the time.  It just depends on what I am doing, and how I am going to use it,  that determines which thickener I a going to use'  If I am going have exposed joints, but not worried about strength, I will used very  fine saw dust from the project that I am working one.  This is the most common use for me.  If I need a thickener that wont weaken the bond I use the West System 404.  It is a silica based thickener that allows you to adjust the thickness without affecting the bond.  but it is pure white I will very much show on an imperfect joint.   Over the years I have use, used coffee grounds, saw dust,  one of my kids even wanted me to use egg shells for her project, that even worked.

Thanks for the info!  When you use saw dust does that “dry out” the epoxy?  I was just not sure how the epoxy would react and if it would look “lumpy” or still dry flat. 

[Woodworking_Hobby]

Thanks for all of the suggestions.  I ended up using the pre-thickened 665 that comes in the squeeze tubes and it worked great for my needs on this one. It dried pretty clear and was kind of like the consistency of silicone caulk when it was applied so it stayed pretty well in the joints I was trying to fill. I used so blue painters tape to keep the lines crips and off the wood and that seemed to work well in this application.