Cuts to help stop cracking

[gobbypunk]

Hi guys I have seen some people put cuts down the back of a piece of work to help stop it cracking I have never done this as none of my work so fay would allow for it however I have a castle tower to do next week its about 8ft tall and it is going to sit in a corner of a garden I intend to have a drainage hole so the crenelations can drain as the back of the tower will not be seen do you think a couple of cuts down the back would be a good idea I will work out how to put up pictures so you all can have a look ,I look forward to your views

cheers Mark

[dervishcarving]

Might work but no guarantees. cracks are likely to start from the heartwood at the top so a plunge cut there might help, but then you are risking letting water in which can add to the problem. I had similar worries with teh 19 foot (yes, 19 foot) tower i carved a couple of days ago. i added a few expansion cuts at the top (disguised as stonework) but its still likely to crack. especially as its so tall they are not going to be able to oil it!

[gobbypunk]

Hi dervish some pics would be good ,some cracks would help add age to the stone work how long did it take you did you detail windows and a door ,cant they use a ladder to oil it

Cheers Mark

[Goodpig]

I believe( don't quote me on this) a lot of old native totem poles were pretty much hollowed out, like a horseshoe profile(birds eye view) for this very reason. So the heartwood was virtually all removed. I reckon cuts down the length will help with cracking issues by relieving stresses/tension elsewhere. Not tried it personally, just theoretical but if I did a carve like that I'd be tempted to try it.

[dervishcarving]

pics are up Mark.

ladder yes, but 19 foot is a bit high for a ladder. hopefuly they will manage somehow. i use a plant sprayer to oil now. dilute the oil wit about 205 white spirit and it flows better. diesel also works according to Simon O'Rouke

[gobbypunk]

Hi dervish cant seem to find pics of tower I used to mix petrol with the oil when on the side of the road drys quick

[dervishcarving]

http://arbtalk.co.uk/forum/chainsaw-carving-forum/72780-radgast-browns-house.html

petrol is probably just as good, just avoid smoking too close

[rooster]

Interesting thread on the yellow forum right now on different carving wood and their properties.

 

Radial cracks can appear in the "sap wood layer" due to loss of moisture more quickly than the "heart wood" The outer wood is shrinking and the inner wood is not, causing stress on the outer layer.

 

Using a "sealer" to control the drying will reduce the "checking" but needs to be maintained. Old school rule of thumb is oil every day for a week, every week for a year and every year forever!

 

Relief cuts may reduce the stress in the outer layer at the back but does not eliminate stress in the front. Hollowing out will eliminate the stress between inner and outer but is a lot of work.

 

Some carvers use "half logs" and "quarter logs" to reduce and even eliminate the problem.