My past is catching up with me. I'm getting ready to finish my Skerry, and I'm sanding. Some of the fillets are way too thick, and I'm having a hard time sanding them down. Because it's the interior of the boat, the orbital sander and a sanding block are both kind of useless. I'm sanding by hand, using 60-grit sandpaper, and there is some progress but it's very, very slow. And corners (where three surfaces come together) are basically impossible. I tried a heat gun at 700, but that doesn't help.
What do I do about this? Is there some way to either eliminate the excess fillet material? Maybe cover it somehow, with enough epoxy? Or do I just live with the problem?
For some reason, posting images inline no longer works for me, but here is a link to an image showing the problem.
http://geophile.com/boat/clc/IMG_2738.jpg
Whoops! Posted the wrong photo.
The bit I used is on the bottom rank
No doubt about it, it's a lot easier to shape the fillets before they cure!
But once cured if they are really rough, before you start laying more down you should at least knock the high spots down. On my early fillets, or one that got away from me, I have used a Dremel tool to do this:
https://www.amazon.com/Grinding-Engraving-Universal-Accessories-Woodworking/dp/B08YJN3NCC/ref=asc_df_B08YJN3NCC/?tag=hyprod-20&linkCode=df0&hvadid=693614504112&hvpos=&hvnetw=g&hvrand=2907938838248531375&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9053011&hvtargid=pla-1216035977452&psc=1&mcid=1904831c2a5a357a829c552c74500478&gad_source=1
I used the rounded cone on the left. Finished up with sandpaper wrapped around a dowel
>> I'm looking into the System Three products. They sand more easily than the fillets I have now?
No. They sand exactly the same as other companies' versions. The S3 literature simply mentioned cosmetic fillets in a way that validated your idea of covering over the lumps and gave some guidance on what fillers to add. The main way that cosmetic fillets reduce sanding is by filling in the depressions and making a uniform surface that has no big bumps that need to be sanded down.
>>Brushing with unthickened epoxy has been problematic for me, it always drips and forms runs which I then have to sand off. How do I avoid this while brushing in enough epoxy to create a smooth surface?
The same way you avoid all epoxy drips - use less epoxy. Put less epoxy on your brush and it won't run off the fillet and make a mess. If it's not enough to smooth the fillet brush it again; if that's still not enough put a little more epoxy on the brush and brush the fillet again. Don't try to do the whole fillet with one brushful of epoxy.
If it refuses to work for you, then try the gloved finger dippped in denatured alcohol. The alcohol will evaporate instead of run off. I won't use that technique, but others have with great success. If it works for you then go with it if that's the only way to avoid sanding hell.
Laszlo
ggray, I was wondering about something like a Dremel.
- I'm guessing that the bits will wear out, and I'll need a few of them, is that right?
- What kind of texture do you get? Why is that last sanding step required?
Also, which Dremel? There is quite a range of models of the rotary tool.
Thanks Laszlo, I'm looking into the System Three products. They sand more easily than the fillets I have now?
Brushing with unthickened epoxy has been problematic for me, it always drips and forms runs which I then have to sand off. How do I avoid this while brushing in enough epoxy to create a smooth surface?
I eventually got a set of the "riffler" rasps to take care of stuff like this. I see that CLC no longer sells these. Hmmmm. Maybe a curved chisel, honed good'n sharp, might answer for you. Easy does it!
A search for "riffler rasp" on Amazon or just in general will turn up some options, maybe even the same set CLC sold if you look hard enough. Came in a red velvet roll up.
I feel...or felt...your pain, and wished I'd been more careful in smoothing things before the epoxy cured.
System Three's literature refers to cosmetic fillets. For painted finishes they're epoxy/phenolic microballoon mix; for varnished it's epoxy/woodflour. You simply apply enough material over the bumpy fillets to fill in the holes to the level of the bumps. When they've cured, just sand them with paper wrapped around a dowel. The grit size depends on just how smoothly you put on the cosmetic fillets.
For any fillet, cosmetic or otherwise, brushing it with a chip brush dipped into unthickened epoxy will let you "paint" them smooth. Once you get the hang of it your fillets will need almost no sanding at all. Some folks do this with a gloved finger dipped into denatured alcohol, but if you use the same epoxy that you mixed the fillet with you will never have any contamination issues.
Laszlo
PS - I can see your picture in your first post just fine.