Jalvis said:
I'm no expert on Timber frame construction but my guess is that Arunda has certification for loads and strength using there jigs. Perhaps thats what the additional cost is getting you.
Should say comes with a book with all the spec for load bearing etc.
Their are brackets, screws you can buy which are structural they have had to go trough tests to get a certification but you don't pay £400 for one structural screw do ya.
I can't see them being able to give you a garantee that the joint used would be fine.
There are to many different factors which could cause the joint not to be as strong as it should be. So if anything faild it would never be their fault anyway. So the certificate would be worthless to the user.
The one I linked Lagina to me seems a far better jig than the Arunda jig not sure but I think its cheaper aswell.
Jmb