AWGB Woodturning Forum
General Category => General Discussion => Topic started by: Vestas on April 27, 2019, 01:42:32 PM
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Hi see the attached pic piece of lime.
It has a large crack issue - advice please - I’ve tried filling it with superglue - anything else? In the bin ??
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colored resin fill then turn to finish?
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Thanks for reply a ive not used resin yet but have seen a few videos etc of it being used - can amyone recommend a brand ?
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First and foremost, superglue is not a filler.
It's not easy to see from the picture, just how wide the crack is, but try using resin, as Lazarus mentioned, in the following way....
- ...clean out the crack, especially near to the surface
- mix up some 2-part epoxy (Araldite, or better still, a cheaper alternative like 151)
- use a filler to give body to the resin...this could be small shavings and dust from your piece of work, dried coffee grounds, metal powders such as copper or bronze, or any other filler you can think of, but work quickly because that resin's going to harden soon
- pack the crack with the resin and body filler mix until it stands proud of the surface
- set aside to dry....the resin may well go off in 10 minutes, but it's not fully hard for some time longer. Experiment with how long your particular brand of epoxy needs
- using sharp tools, cut the excess resin back, top up the filled crack if any surface voids are visible, repeat the cutting back
- abrade to a finish
The list of fillers is endless...be imaginative!
Les
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What Les said...
that looks like a bark inclusion to me, but hard to tell scale. They add interest to the finished piece, but can be unstable and hard to work with.
As you know I use a bean to cup coffee machine, and that makes a great filler for this colouration, if it is smaller than it looks then something finer e.g. metal powder or sawdust, next time you are around or remind me before the club night and I will give you a bag out of the bottom of the bandsaw, it is the perfect grain size!
as a general rule, but not always followed
- Very small hairline cracks I use CA glue with metal powder or fine sawdust
- medium cracks around 2 or 3mm I use epoxy with appropriate filler
- larger and I really want to turn it, I may use fiberglass resin instead of epoxy
- I have not done it but have seen great stuff done with coloured crystic resin
Epoxy needs at least 8 hours probably 24 before you attempt to turn it, I am told Crystic may need a month.
Some caution needs to be applied, if the split is looking like it will reach your chuck, expansion or contraction it will at some point leave the lathe and aim for your head! I am not saying never turn it, but make sure it is worth the risk, keep the speed reasonable, and be certain your face shield is on properly!
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Vestas the previous commtes are worth followingas both give good advice. Looking at the picture I can see screw holes that appear to be from a faceplate so I assume (assume makes an ass of U and me so I need to be careful)I assume that the face side has already been turned. If that is the case you may tru hot glueing the face side to a plywood faceplate and gently turning the split side down, the split or crack may well disappear but if not finish it anyway and then lace the crack up with wire or leather or even a nice piece of ribbon.
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Thanks all
I initially put the face plate on the visible side but decided to change after the cracks appeared - I hedged my bets as to the best area to hollow out - resin it is ! I will order some - any suggestions to make and where from would be appreciated
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Thanks all
I initially put the face plate on the visible side but decided to change after the cracks appeared - I hedged my bets as to the best area to hollow out - resin it is ! I will order some - any suggestions to make and where from would be appreciated
I've been buying a make called 151 for a few years and have been very pleased with it. Once mixed, it stays open for about 5 minutes, which is plenty of time to add a filler and pack it into a crack. It dries fairly quickly, but the time is governed by environmental conditions, so you will need to do a test fill on something, but once dried it goes hard and cuts/sands back very well.
https://www.ebay.co.uk/itm/2-PART-EPOXY-GLUE-ADHESIVE-TWIN-SYRINGE-CLEAR-STRONG-RESIN-PLASTIC-GLASS-METAL-/113680829141?var=&hash=item1a77e7cad5, Here's where I buy it, 6 tubes at a time, which gets the price right down.
Les
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Although all previous replies provide good advice on the subject of filling cracks and voids, on this occasion, and considering the timber is lime, I'd say put it in the bin.
Lime is a very soft wood, and almost all of your fillers will give you a much harder material in the crack. You will end up with a serious bouncing problem. In addition, the filler will create a weight distribution problem, which means you can't turn the speed up, and that'll probably make the bouncing worse. And as soon as you start to sand the stuff, the lime will sand a lot faster than the filler. Unless you have a seriously big lathe, and some very good turning skills, you are very unlikely to end up with a satisfactory result.
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I do agree with Fuzzy. If you are not confident, don't turn it.
Not saying you should throw or burn it though.
It can be put to one side for even quite a long period of time and you can come back to it when you feel you have the experience to deal with it.
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Thanks guys
It went in the bin!
I had a multi pack of blanks from home of wood but unfortunately two of them (the two biggest pieces) were unusable. One had a full crack and it fell in half. I contacted them and they were really good and said they would replace them in next order