Resin use

[Democritus]

I need some advice. I bought a couple of eucalyptus bowl blanks recently. Both of them are generally ok, but both have a few shallow splits across the faces, and what look like rows of tooling/milling marks about 2-3 mm deep on the edges.(see photo). I thought I might use resin to fill in these defects, but, never having used it before, I thought i’d consult YouTube.
I thought it would be fairly straight forward, but having looked at some videos, I’m even more confused about its use. It seems that there are two types of resin, casting, and another used as filler. Is that right? If so, which do I need?
Also, on the YouTube videos showing bowls and other stuff being turned with resin, there seems to be a need for some type of pressure vessel to cure the resin. Is that also right?
If that is the case, i’ll not bother.
D

 

[julianf]

You get different setting times for resin. The slow setting ones are tedious BUT they are all I use, as they creep so well, and penetrate down into the job over time. So I just accept the time element.

They all give off heat as they set. Another advantage of a slow setting one is that you can pour deeper in one hit without it going exothermic.

I use glass cast somthing or other.

The pressure things are not needed. People do one of two things -

They either put the whole job in a pressure vessel to compress the air bubbles so small that they don't show up, OR...

...they put the resin in a vacuum unit to suck out the air from the mix.

To me, the second one sounds like a nice idea, but it's not required. Especially if you use a slow setting resin, the air has more time to work its way out. It's not fool proof and you may need to do touch ups but it's not bad.


#1 tip for resin work (I'm on my phone and have put bold on by accident and can't get it off again now, but it's appropriate anyway!)
-

get the quantities spot on (use proper scales, with a decimal place, or places for tiny amounts) and mix well. When you think you have mixed well enough, mix for about 2/3 as long again. (Scientific, I know!)

 

[julianf]

Be aware that the slow setting resin will creep (as you want it to) and find cracks to leak out of that you didn't even know existed.

In the early days it wasn't uncommon for me to end up having to mix more resin as it had all ended up below the job without me realising...

 

[Ollie78]

The pressure vessel is not to cure the resin but force it into the places it should go, might actually be a vacuum chamber.
My mate does turning and uses cactus juice which is very thin and soaks into cracks.

 

[Democritus]

Cactus juice?

 

[Phil Pascoe]

Google is your friend.

 

[TRITON]

Cactus juice?

Google is your friend.

I still cant see the connection

 

[Democritus]

Thanks, Phil. I’d never heard of cactus juice resin.
Having watched a couple of YouTube videos about its use, I have discovered that it is fabulously expensive, needs a vacuum chamber, mixing equipment, and maybe a microwave oven.
I think i’ll convert my eucalyptus blanks into tooth picks or something.
D.

 

[Orraloon]

Those defects are gum veins and eucylipts usually have them. Normally you attend to those when the bowl is nearing its final shape and size. Normal 5min epoxy can be used mixed with sawdust, coffee grounds or even dyed for wider voids and for thin ones CA glue and sawdust, coffee grounds or whatever you think looks good. If using epoxy a warm up of the wood with a heat gun helps the glue flow in.
CA and coffee grounds repair – Wood Turning Basics
Regards
John

 

[Owd Jockey]

Depending on the size of the crack, you could use the 5 minute resin from Gorilla. I've used it a few times on my turned stuff.

 

[Richard_C]

For small cracks I often wait until the bowl is almost done, run in some CA and pick up some dust/shavings from the lathe bed and rub them in with a finger. 5 minutes later do a light final cut and sand.

 

[Democritus]

Thanks, guys. Some really helpful advice.
I’ll get some 5 minute resin and thin CA, and have a go at sorting the blanks out during turning them.
D.

 

[alex robinson]

Be aware that the slow setting resin will creep (as you want it to) and find cracks to leak out of that you didn't even know existed.

In the early days it wasn't uncommon for me to end up having to mix more resin as it had all ended up below the job without me realising...

I will second this! It does not matter how slow the leak is, if it takes days to set, everything will end up coming out. Filling bowl blanks is also surprisingly hard - because they are round you need to pour from loads of different angles so the whole thing takes ages.

Something else to be careful of is staining if you are using anything apart from clear resin. Resin will penetrate a long way into end grain, so any before pouring any colours onto end grain, you need to seal with a coat of clear.

 

[MARK.B.]

From the picture I would think that if turning a bowl/platter ,then you will most likely lose those defects in the turning of the piece anyway.

 

[julianf]

Something else to be careful of is staining if you are using anything apart from clear resin. Resin will penetrate a long way into end grain, so any before pouring any colours onto end grain, you need to seal with a coat of clear.

I use that "perl" colourant the bulk of the time. I think is more like a "dust" in the resin, rather than a smaller particle size "dye". Ive not found the staining as bad as the dye ones. But then i guess i dont really ever get it near much cut end grain, so i probably wouldnt know how well (or badly) it would stain here anyway!

I use it for this kind of stuff -

 

[alex robinson]

I use that "perl" colourant the bulk of the time. I think is more like a "dust" in the resin, rather than a smaller particle size "dye". Ive not found the staining as bad as the dye ones. But then i guess i dont really ever get it near much cut end grain, so i probably wouldnt know how well (or badly) it would stain here anyway!

I use it for this kind of stuff -

View attachment 139189View attachment 139191View attachment 139190View attachment 139188

Very nice! I have been filling some voids in a very punky piece of willow and the test piece without the sealing looked awful.

 

[Morag Jones]

Coffee grounds and resin is an interesting one. Does the grind size need to be small?

 

[Inspector]

You don't need to limit yourself to coffee grounds. Any powder with a shade or colour you like is fair game. Old spices like mustard, curry etc for example. Semi precious stone dust, brass fillings, just about anything you can think of have been played with.

Pete

 

[Morag Jones]

You don't need to limit yourself to coffee grounds. Any powder with a shade or colour you like is fair game. Old spices like mustard, curry etc for example. Semi precious stone dust, brass fillings, just about anything you can think of have been played with.

Pete

I shall have to experiment!

 

[alex robinson]

I shall have to experiment!

Most important thing is that it is completely dry.

Powders make it a lot thicker, but enough metal powder and it looks almost like a solid inlay. Heating the resin component before adding the second part can help.