Epoxy thickener

[alex robinson]

I think if you're leaving the walls reasonably thick I'd just turn and finish that as is, the cracks are part of its charm. If you're really worried about it exploding I'd run thin CA into the cracks (but don't fill them fully) and a quick spray of accelerator. That'll be enough to stabilise the cracks and stop them propagating while you finish turning.

The cracks are definitely part of the charm, but I would like to emphasise them with black epoxy. Not as look for every project, but can look quite striking. Definitely agree about the super glue + accelerator for stopping cracks spreading

 

[alex robinson]

Hi Alex, I have tried a number of different methods to fill cracks/voids on my turned pieces over the years, including CA glue, PVA Glue, Milliput, epoxy resin resins etc, each with a measure of success. I have recently changed to simple wood filler, which I sometimes colour. The problem with 'pourable' resins is you are reliant on gravity doing its bit,however, like others have mentioned curvature of the 'piece' may require damming and or gentle heat to release air bubbles (Ok you could use a Pressure Pot to do the same thing).

With the wood filler method, I use Ronseal Hi-Perf Filler, you can work the paste into the voids, BUT you have to be quick as especially in summer it goes off quick, so little and often.

Of the options you have tried, how would you rate the levels of shine you can get in them? Something that was a paste that could be polished to a low gloss would be perfect!

 

[Paul Hannaby]

If you don't care what colour, why not just mix the epoxy with some wood dust, it makes a great filler and is kinder to the environment than all that artificial stuff! You can also mix wood glue with wood dust to do the same.

 

[pat from Marck]

I agree that low viscosity is good where the cracks are narrow and it is important to stop the piece from splitting. It is still a pain using something runny when they are lots round the diameter of a piece - each needs to be filled and left to set before the item can be turned and the next one tackled, leading to a lot of waste. Also, if you are filling a curved surface, the caulk has to be built up to the level of the highest bit of the curve.

I am not particularly worried about the strength aspect - it is more the aesthetics. This is an irritating cherry root ball I am working on:
View attachment 189497
The grain is all over the place (and full of stones it has grown round so perhaps the most tedious / least fun thing I have ever turned) and I am not planning on making the walls very thin, so I don't worry about the cracks spreading. The wood is also soft in places, so I couldn't use a thin black epoxy first as it would mean too much staining (would need sealing with clear). Something that could be spread on and worked into the cracks as a paste would nicely highlight them.

Hi alex currently working on a cherry burl and have had success with coffee granules and ca glue the colour match for me is fantastic as for the rest epoxy resins sealents etc cant comment as I'm just a beginner and still learning

 

[alex robinson]

Hi alex currently working on a cherry burl and have had success with coffee granules and ca glue the colour match for me is fantastic as for the rest epoxy resins sealents etc cant comment as I'm just a beginner and still learning

I have seen your cherry burl family and it is beautiful. Sometimes hiding cracks is nice, but I wanted to see about highlighting them this time.

I think I am also having the opposite problem with turning it. No need so far for hardener, but endless grit and stones in there wrecking my gouges.

Seems a good excuse to try making a carbide hollowing tool!

 

[Owd Jockey]

Of the options you have tried, how would you rate the levels of shine you can get in them? Something that was a paste that could be polished to a low gloss would be perfect!

Hi Alex, a good question and one that is quite difficult to answer, as I very rarely ever let a 'crack' develop over 2mm wide. I always aim for a very high gloss finish with various waxes, attempting to emulate the sensation of touching glass. Before doing so I must first remove any 'step' or ridge across the crack. Because the crack is so thin, it is virtually impossible to spot any difference with the surrounding wood.

For a much larger crack, or void or inlay. Probably the best finish (IMHO) would be Epoxy Resin, whether that is the pourable stuff or the instant Gorilla resin you get in a tube. Virtually all of the infill glue or fillers I have used will take wax and it is that what gives the finish.