Metal detection.

[Peasgood]

There are two types of detectors (excluding the pi ones which I would ignore) they are motion and non motion. The motion detectors work by passing the detector over the metal, they are silent if held stationary over the target.

If you are trying to find the cheapest way of detecting metal I would suggest a high quality non motion (or "all metal") detector and sweep over the wood before each pass of the saw.

I have experience of various "treasure hunting" detectors and they might work, I wouldn't be surprised if the "security" metal detectors might be better as they are a bit more wand like.

It will take a bit of experience to figure out what the detector is telling you as there are usually different sounds and signals depending on the depth, material and size of the target/object.

 

I think the post above that says forget about it and use your best judgement and indicators such as stains to tell you is the best advice.

[Macpherson]

I thought standard practice to mitigate damage when the detector indicates metal is to mark the position, mill from one end as close as you dare and then come from opposite end to a similar safe point, split board off with wedges and test if it contains the metal usw.

 

yep again, that makes sense,and I`ve seen that,and that`s what I`ll do. But I ain`t done it yet ,so that`s why it`s great to be able to learn from the experience of all you guys. Thanks, I Feel that I`ve been at college every time I come on here, great stuff.

[agg221]

If the nail is 5 or 6 inches inside the tree i might not see it but i check teh whole log at the start and then now-and-then as i progress (as i assume you would). a cheep one is better than nothing and if you give the log a swipe after a couple of passes of the mill wouldnt you then be detecting any metal deeper in the wood?

 

Yes, you would run a swipe each time you've removed a few inches and it would tell you if there is something coming up. This works completely when through and through sawing, but when you're quartersawing, the first two cuts are going so deep that you won't get a detector to tell you what's there.

 

Re. the technique of milling close from each end and splitting the board off - that's quite cunning - if I ever get a detector I'll have to remember it.

 

Alec