I have always used boge joints and I have been watching it in motion lately and realised they sure do stretch and bend a lot under power and speed especially when using my larger sails and there's a bit of chop. My question is are tendon joints immune from this and can you feel the difference. I have been reluctant to get one as My understanding has always been the closer the sail is to the board the better, all the tendons seem to be 30 to40mm longer than boge joints does this tiny bit of extra height matter?
I have never seen any Boge joints when checking out the gear in the close-up photos here ...
www.pwaworldtour.com/
I prefer tendons. The best tendons in my experience are the tan tendons from Streamlined. If they start to develop cracks, you can see the cracks before they fail. That's when I change them. I have never had one fail completely.
The black tendons from xxxx have not lasted nearly as long, and they have failed without any warning.
Boge joints are glued to a metal piece that may corrode from below and detach without warning.
Tendon are more flexible which makes the sail feel lighter and more reactive. I've used a Chinese one for a few weeks with good results.
More details here under "mast base"
windsurfing.lepicture.com/tips-and-tricks/
I like the clear tendons with safety line running through them, North/Duotone I think?
I have also noticed that tendon bases can be significantly longer in general than Boge bases. I have both types. For my speed and slalom type sailing I prefer to keep the base short and the foot of the sail close to the board to gain advantge from 'c;osing the gap' between the sail and the board.
However, I recently got a slalom board with a 'sunken' deck for the mast track. On this board, I use the tendon base as the Boge types are almost too low when rigged almost pulley to pulley on the downhaul.
It is my experience that the Boge joints last a lot longer than tendons but are also more expensive to buy replacements. Some say it is easier to inspect the tendon type for cracks and the need to replace, but I have leaned to spot the signs of potential failure with the Boge and replace them when I see it. I have not had one break in use for many, many years and then the 'safety strap' saved the day just like the tether ropes on the tendon joints.
I do find the Boge type has a sligtly more 'shock absorber' feel than my particular brand of tendon base, but it's not that significant for me.
Select to expand quoteShifu said..
I use tendons because i can't pronounce "boge".
Isn't a boge something you pick out of your nose?
Well after watching a few company videos in German it seems it is pronounced Boa-gah - about as close as I can get.
47 seconds in:
I use both the Boge and the tendon and have found the following:
Boge. Never had a Boge fail either by rubber breakage or the internal steel parts corroding. Note: these are the genuine Boge with that name moulded into the rubber at one end, on its visible side. I've seen replacement joints available on-line and in shops where the joint is described as a Boge but they don't have the Boge name moulded in, so it's a copy.
Black tendon joints. Found most failures originate in the through-bolt holes, where you can't see it happening until it's too late. Second type of failure starts in the centre of the joint and can be identified because the centre starts to bulge. Third type of failure is also in the centre and it fails without warning.
Before fitting a tendon mast base to a board, I bend the tendon in my hand to see if any cracks open up (doesn't always work as I found out recently).
Clear tendon joints: replaced my remaining black tendon joints with the clear ones. No failures to date. Others could offer their experiences?
Agree with Imax1 that, if you're sailing a lot, replace the tendon on a yearly basis.
Hope this helps.
I have two joins mast bases in my quiver . I replace my main one every year and hand me down to my second older one . I sail a good medium amount . It costs me $ 25 a year to do this and never ever had a failure. .
When I returned to windsurfing after a 20 year holiday I bought a $50 dunger for a experiment .
In the back yard I pre rigged .
All good apart from the bogie joint . It didn't just break , it shattered in four pieces .
Still trying to smile , I bought a second hand tendon mast extension .
rest is history and still
Give yourself a $ 25 Christmas present
Select to expand quoteImax1 said..
When I returned to windsurfing after a 20 year holiday I bought a $50 dunger for a experiment .
In the back yard I pre rigged .
All good apart from the bogie joint . It didn't just break , it shattered in four pieces .
Still trying to smile , I bought a second hand tendon mast extension .
rest is history and still
Give yourself a $ 25 Christmas present
LOL! There was your problem! You got a Bodgie one. 
I started windsurfing about 6 years ago and given I am old-school..... I stuck with older/large boge joints for about 4 years.
My opinion, although I have not gone over 30 knots is:
1) easy to change New tendons
2) best new tendon is salmon coloured (Streamline) - as you can see cracks first as per previous quote, however the clear and black ones I have got from Simon have never broken---- ever.
3) tendons comes with different hole sizes (so I had to drill holes to make bigger, for Streamline and it was not easy)
4) I had to put small flat stainless-steel washer or two as tendon needs to "rest" in cup - not on pin
5) best large/Boge joints are 'chinook' brand. Boge do have an alloy moulded in rubber that corrodes much much faster than brass inset in the chinook old type. Sorry but it is true!
But here is the real fact.... I use sails from 4.2 till 10m. In Brisbane 10m and 9 m and 8.5m regularly. These do not feel as stable on tendon. I feel a small bad movement sometimes - but use to it now. Small sails - 5 - 6 metre feel looser at base with tendon which I like.
It is much harder to get old larger/Boge type ones.
By the way when they do break - the old large type (they break sometimes in middle) but sometimes at the end - then they can break above the thread to each end. On this occasion, the Boge corroded out of the rubber and corrosion weakened top of strap and it broke as material was soft from corrosion. This has means the safety strap does not work, as it is torn from corrosion. I got towed in by friends, Thus I still use older chinook make but not one marked Boge (sorry to those that make these).
No tendons have failed on me - so I have no idea if string will hold.
I did see a tendon that had a string on the middle (yes - moulded into rubber!) - and one can then use strings on sides. DOUBLE safe! But apparently they are more expensive and I am not sure how to source them.
And the winner is... Mechanical tendon!
chinooksailing.com/products/2-bolt-pro-flex-mast-base-euro-pin-ex
Select to expand quoteFaff said..
And the winner is... Mechanical tendon!
chinooksailing.com/products/2-bolt-pro-flex-mast-base-euro-pin-ex
Not a bad design!
Much better than this one ....
chinooksailing.com/collections/mast-bases-pin-style/products/2-bolt-quick-release-upper-mast-base-universal-euro-pin-1
^ this one works perfectly well too !
especially for foiling where shock absorption is not really needed
Select to expand quoteJakeNN said..Faff said..
And the winner is... Mechanical tendon!
chinooksailing.com/products/2-bolt-pro-flex-mast-base-euro-pin-ex
Not a bad design!
Much better than this one ....
chinooksailing.com/collections/mast-bases-pin-style/products/2-bolt-quick-release-upper-mast-base-universal-euro-pin-1
One flaw. 2 bolts into the mast track reduces the usable length of the track by about 3-4cm at both ends.
Select to expand quoteMr Milk said..JakeNN said..Faff said..
And the winner is... Mechanical tendon!
chinooksailing.com/products/2-bolt-pro-flex-mast-base-euro-pin-ex
Not a bad design!
Much better than this one ....
chinooksailing.com/collections/mast-bases-pin-style/products/2-bolt-quick-release-upper-mast-base-universal-euro-pin-1
One flaw. 2 bolts into the mast track reduces the usable length of the track by about 3-4cm at both ends.
There's a single-bolt version:
chinooksailing.com/products/1-bolt-pro-flex-mast-base-euro-pin-ex
Boge joint every time for me, and a regular turnover of deckplates.
You do need to check it's a proper Bone joint - which is labelled as such.
I buy Duotone single bolt deckplates - and North ones before that.
The Chinook ones look shiny and reassuringly over-engineered but they are also heavy.
Select to expand quoteBasher said..
Boge joint every time for me, and a regular turnover of deckplates.
You do need to check it's a proper Bone joint - which is labelled as such.
I buy Duotone single bolt deckplates - and North ones before that.
The Chinook ones look shiny and reassuringly over-engineered but they are also heavy.
I guess you haven't had one of those threaded on euro pins break on you. Or do you use pinch pins?
Select to expand quoteNotWal said..Basher said..
Boge joint every time for me, and a regular turnover of deckplates.
You do need to check it's a proper Bone joint - which is labelled as such.
I buy Duotone single bolt deckplates - and North ones before that.
The Chinook ones look shiny and reassuringly over-engineered but they are also heavy.
I guess you haven't had one of those threaded on euro pins break on you. Or do you use pinch pins?
My post should have read 'Boje' joint.
I have two deckplates on the go at any one time, and I replace the one with the looser bearing each year with a new one.
One thing you watch out for is any signs of rust on any stainless steel components. But I have not had a pin go on me in recent years.
Select to expand quoteNotWal said..
I guess you haven't had one of those threaded on euro pins break on you. Or do you use pinch pins?
On that point, I have not had a Euro pin break since I started ordering the Boge joint and Pin separately and assembling them myself.
A couple that I bought pre-assembled about 5 years ago failed quite quickly. After the second one, I had a really good look at the remains of the pins and realised they had been overtightened to the point that they were badly fractured before I even used them.
Since assembling them myself, I have had no problems. I have 2 or 3 on the go all the time as well as 2 or 3 two bolt bases, and they get used randomly, unless I see the first signs of the Boge joint starting to split around the end rim. If I see that they get chucked, but that happens maybe only every 2 or 3 years. Apart from those two pre-fractured ones, I have never broken any others and I have been using them for at least a dozen years.
^^ I haven't broken euro-pin since I started using the Chinook one where the pin is not separate, its part of the top cup the tendon goes into. Bulletproof. Even then I didn't break europin anywhere near as much as the US cup wear annoyed me.
Got sick of shearing the double pins off the US cup system
Has anyone used the seemingly-the-same tendons from China that are about $5 not $30? Could be one of those same-factory type situations where it is great value - or a big China fail. I'm not game yet, but if anyone has tried them.....
I've looked at them and I'm not against 'made in China' stufff at all. Most the equipment I use for cycling and windsurfing is made there but where it comes to some like a tendon that is really easy for anyone to make out of pretty much anything it nice having a big brand name attached to it so you know it's not made from an old eraser.
Wow, I was sailing a 4.2 when wind skating and noticed that darn yes the boge flexes a lot side-to-side! Yet it feels stiffer than a tendon. One most point to add to my FAQ.
Mark, shearing us clip pins? How often? Oval shaped holes? Could you tighten the top nut? Added a washer if not? I keep mine tight. Broke 2-3 clips in 1300+ sessions.
I like mechanical for foiling, easier to attach the ext. in the water. I like tendons for windsurfing, smooths out the chop a bit. I've been stranded with tendons more than once, haven't had a issue with mechanicals ....yet.
Check these out, best of both worlds.
come in a US base and one bolt also.
chinooksailing.com/collections/mast-bases-pin-style/products/2-bolt-pro-flex-mast-base-euro-pin-ex
