wood can be treated by Oil or not

[doyenofcastle]

I have read some specification and I just want to share
to determine the wood you choose can be treated with teak oil or need seal like epoxy u need to look for 3 elements : if wood grain is straight ,the wood in data sheet doesn't required any preservative treatment in humid environment and if it stable dimension wood , 3 should be together , for ex. Teak ,Padauk ,merbau ,Kapur have all of that so u can use oil for finishing but mahogany or iroko will have moderate stability and also interlock grain that's why u need to seal by paint .

 

[foxfish]

Do you think that applies to spearguns that spend hours under water?
Do you think that oil will offer enough water resistance or offer any form of protection from rocks etc. ?

 

[doyenofcastle]

this question difficult to answer if the gun I have built survive for 5 yrs I ll know but just built them for 1.5 years only and they do fine till now ,it will be water resistance if the gun is proper coated by teak oil ,protection from rocks of course not similar to hard coat of epoxy ,but if a teak gun sealed by epoxy have small pin holes or hidden coat cracked from services and it allow water to penetrate inside the stock what will happen ?anyway i am going to use linseed oil for my new padauk/bilinga gun and give it a try .

 

[Bill McIntyre]

As far as I know, even oil isn't necessary for teak. I know two different guys who owned Riffe Islands that looked as white as driftwood. When one of them was visiting me I offered to put a coat of teak oil on the gun and he almost punched me. He took pride in the fact that he never put any coating on the gun. When I owned a Riffe Island, I put a coat of tung oil on it about every 6 months to a year, but I considered it to be more of a cosmetic thing. I presently have four guns with epoxy finishes, but sometimes I think I'd prefer that they were just oiled. Its hard to repair a chip in an epoxy finish, but its easy to rub on some oil.

I have two mahogany guns, and I suppose the epoxy finish is necessary for them. Or at least I've been told that.

 

[doyenofcastle]

when u visit shipyard u find them using either oil ,varnish ,PU or epoxy to protect the wood ,for Oil they usually do for specific species ,I checked through database and all of that wood shared same character straight grain ,very stable and famous of doesn't affected by wet environment and when we look at RIFFE and other famous gun builders they won't use oil for teak or padauk unless they already study and do experiment otherwise their reputation will be affected

 

[doyenofcastle]

if you choose oil finish one problem here ,how to balance the spear gun without protection?u need to apply oil after fixing your weight otherwise the glue won't work in case of oily surfaces ,I was searching for some solutions for this and I think best getting sample from your stock and check how much lead will ballast it then get the ratio after that drill some holes in your stock and keep it ready after applying your oil using a stainless cap to cover it ,Ex. stock of padauk 160 cm long cut your specimen at one end like 3 cm 5cm by 6 cm and bring seawater in small jar check your stock in gram then add lead till it submerse under water line ,take the lead and weigh it let say wood was 100 gram and need 30 gram of lead so ratio is 30/100 ,when you have 1.6 kg wood speagun you will nedd a 1600*30/100 = 480 gram approx. more or less spear with trigger is ??? usually trigger with accessories is 200 gram so 280 gram is needed which can be the spear weight in padauk case you don't need holes in your stock but if mahogany diffidently u will need some .

 

[sharkey]

Just coat the gun in two pack PU. This stuff is super tough. Finish the gun in this, then take it out in the water to play with the ballast. Its easy to recoat where you have added the lead. I have resisted using oil on timber guns for decades (including good Burmese teak) & am not likely to change my opinion now. I remember when we just had marine varnish & that IMO was still better than oil, then in the 80's we started to get two pack PU's which was a major improvement over varnish, now these latest two pack PU's are fantastic. Oiled guns still require maintenance & the best "oily" timbers will still absorb moisture, a two pack coated gun doesnt require maintenance as often & absorbs less moisture (particularly if it us used daily & for extended periods), a good sand back & a few new coats every year or two will keep them working for decades.

 

[Giorkos]

Hi all.just to state my experience with wood, especially mahogany and teak oil. Please visit this link
http://thespeargunshed.blogspot.co.uk/2014/09/some-speargun-tlc.html

You can see a gun I built and never looked after it. You can see the part of wood exposed to rocks etc and also parts that are bit protected from it, like the trigger slot and weight ballast slots.

Needless to say that I made some simple experiments with submerged pieces of mahogany , both treated ans untreated and I can say that oil provides very good protection. Heck,even u treated wood was perfectly fine . Just to tiny water ingress from the endgrain but none along the length of the wood.... Never used epoxy as sealant so cannot compare the 2.

Thanks,
George

 

[doyenofcastle]

I just want to know how you ballast your gun ,mahogany have high buoyancy ,did you bring your raw gun without any preservation to see and fix your lead ? how was the effect of seawater on raw mahogany ?do u know how deep the oil will penetrate the wood ?