Fixing Large bird boxes

[Paul Smith]

I have been asked to fix a lot of owl boxes, they are large about 40Lbs! I have been told they are going to screw them to the trees! Not rally happy with this so I have been racking my brains to come up with a non invasive mounting method. Maybe a couple of ratchets with offsets under the straps to try prevent strangling the cambium? These would need adjusting as the tree grows though. Another idea was to girth hitch a sling and suspend. This in theory would allow for expansion.

 

Any body got any better ideas?

[coppiceer]

A very worhtwhile project that deserves to be done right.

 

You could try asking the Hawk and Owl Trust for their advice. They have a page to contact their local groups:

 

Hawk and Owl Trust | Groups | Local groups

[Daniël Bos]

Stainless decking screws.

They'd not do that much damage going in and then they'll just stay. If you can use them with washers and a spring like the tree-tags, they'll leave room for growth.

Straps will need re-adjusting, and perhaps resetting every so often. I reckon they'll end up being worse.

[HCR]

I've used nylon coach screws for owl boxes in the past. Can't remember the size but M10 ish.

[Goaty]

Nails in trees:thumbdown: unless aluminium saws handle that no problem.. Someday somebody is going to ruin a chain or a tct circular blade. I know how I feel when that happens:cursing:

With these sort of things they only tend to last around 7 years tops, likewise I'd make your fixings degradable as no one ever takes these things down.

Maybe ait will fall whilst occupied but any roost or nest can.

How abouts some old seatbelt webbing nailed into side of box, wrap around tree all the way round then half way again to reach the other side attach wide a diy buckle. Im sure a scrapyard aint going to sting you for nonmetal.

[delabodge]

Ist choice =galvinised index screw(easy to take back out with impact driver)

2nd choice =/stainless steel screws (although can be soft,and difficult to remove)

the box will rot after 5-7 yrs and you can rpelace fixing,,,,I put a rubber washer on to allow for growth.

[agg221]

With these sort of things they only tend to last around 7 years tops, likewise I'd make your fixings degradable as no one ever takes these things down.

 

That's an interesting thought. Can you dowel them on, like peg joints in timber framing? If you make oak (or robinia) pegs, say 6" buried in the tree, the rest of the length needed to drive through an oak block (say 3"x4") fixed top and bottom of the box, you will have enormous loadbearing capacity and it won't leave metal in the tree. It would be a bit like a residual knot. I'd probably go for 25mm if you can get four pegs in, 30mm if it's only 2.

 

If you've never made dowels, it's very easy. You want a bit of straight grained oak of the right length plus a bit, then shave it round-ish and drive it with a mallet through a hole the right size drilled in a bit of steel plate. taper the tip to a bit of a lead and away you go. If you make them this way, you want to do it just before fitting as they slightly compress when you drive them through the plate and then gradually swell up again in the hole, forming an even more secure fit.

 

Actually, having seen where you are relative to me, if you do decide to do it this way and need a few dowels give me a shout if you like.

 

Alec

[Sussex Groundie]

I use Plastic bolts and nuts M10 or M12

[Paul Smith]

That's an interesting thought. Can you dowel them on, like peg joints in timber framing? If you make oak (or robinia) pegs, say 6" buried in the tree, the rest of the length needed to drive through an oak block (say 3"x4") fixed top and bottom of the box, you will have enormous loadbearing capacity and it won't leave metal in the tree. It would be a bit like a residual knot. I'd probably go for 25mm if you can get four pegs in, 30mm if it's only 2.

 

If you've never made dowels, it's very easy. You want a bit of straight grained oak of the right length plus a bit, then shave it round-ish and drive it with a mallet through a hole the right size drilled in a bit of steel plate. taper the tip to a bit of a lead and away you go. If you make them this way, you want to do it just before fitting as they slightly compress when you drive them through the plate and then gradually swell up again in the hole, forming an even more secure fit.

 

Actually, having seen where you are relative to me, if you do decide to do it this way and need a few dowels give me a shout if you like.

 

Alec

 

Alec, where are you, sounds like a good idea. Still not sure about drilling though!

[Paul Smith]

I use Plastic bolts and nuts M10 or M12

 

Are plastic bolts readily available?