Hi
I am wondering if anyone knows how to remove bottom section from pictured single bolt mast base. The top pin screws out no problem with a 10mm spanner but I am at a loss as to how to remove the bottom section to enable me to replace the boge joint. There is nowhere to fit a spanner or pliers etc.

Has that got a stud in the joint?
That you are trying to remove?

If so they are normally lock-tighted in. you need to heat the stud to release the lock-tight, then use two nuts on the stud, tightened against each other, with the spanner on the one closest to the joint to undo it.

Short answer, buy a complete new Uni, i tried a few weeks ago with almost the same uni, it's now in the bin.

Buy a tendon uni, they are much better to use and easy to replace the tendon.

The stud is set in the large plastic tightening nut so independent from the stud that is into the boge joint. I think ill just get a new one there $70 and the boge joint is $40 anyway

If you look under the base you will find the way it has been connected. Some are screwed in place with screws others need to be twisted. this will then give you access to the pin screwed into the boge which then can be unscrewed from the boge if you can overcome the lock tight.

forgot to mention some have two small holes in the side of the plastic tightening base they require a small allen key to unscrew the the 2 studs holding the pin screwed into the boge in place. once unscrewed the pin can be removed and it can then be unscrewed from the boge.

Something like this.
Does anybody now where you can get the boge joint with an M8 at one end and an M10 at the other?

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tbwonder said..
Something like this.
Does anybody now where you can get the boge joint with an M8 at one end and an M10 at the other?

Not sure you can get one with odd size threads.
You could always get one with 10mm threads & put a 100mm x 8mm Helicoil in one end.
I know I've previously bought both 8mm & 10mm Boges.

Boge Unis will outlast Tendons x 5.

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Paul Kelf said..

tbwonder said..
Something like this.
Does anybody now where you can get the boge joint with an M8 at one end and an M10 at the other?

Not sure you can get one with odd size threads.
You could always get one with 10mm threads & put a 100mm x 8mm Helicoil in one end.
I know I've previously bought both 8mm & 10mm Boges.

Boge Unis will outlast Tendons x 5.

You should be able to get them with m10 on one side & m8 on other. I don't know of any mfg that uses m10 on the bottom side, but most good Europin hourglass bases use m10 on the top - would not trust an m8 Europin.... Me I use tendons easy to replace & tend to last me 2-3 seasons, which is fine...

Yes I have four bases and they are all M10 Euro pin at the top and an M8 Stud at the bottom. I can't find replacement Boge joints anywhere. I am starting to wonder if they have stopped making them.

I considered buying M10 both ends and fitting an M8 Helicoil but M8 helicoils do not fit in M10 holes

This is the closest I have seen although it is a mechanical uni not a boge.
www.24-7boardsports.com/radz-knuckle-joint-for-windsurf-uj-m8-to-m10/

As PC says , buy a new tendon uni , or a second hand chinook . Replace tendon every Xmas.

^^ agreed

I know I sound like a broken record but the Chinook europin is it. The solution. Period.

It one has the europin as part of the cup (all machined in one piece) so no snapping pins off like before like gorgesailor was mentioning
Plus it has big head allen bolts thru the tendon, so no farking around with corroded phillips head tiny little dinky screws like years ago.
The spin on base enables more adjustment than others, but whatever floats ya windsurfer.

OK maybe Boge lasts longer - but I'd rather spend 5min removing two bolts once a year, than heating, stripping, EZ-outs, swearing, no skin left on knuckles .......every two or three years.
If anyone wants to do that in the sand at a desert campsite with no vice and blowtorch good luck to them.

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tbwonder said..
Yes I have four bases and they are all M10 Euro pin at the top and an M8 Stud at the bottom. I can't find replacement Boge joints anywhere. I am starting to wonder if they have stopped making them.

I considered buying M10 both ends and fitting an M8 Helicoil but M8 helicoils do not fit in M10 holes

.... like I said never seen m10 both ends. Speaking from experience Boge requires large minimum order so maybe not many mfg willing to order 10,000 joints at once... Also Chinook had a supply issue with the their hourglass - the Kinetic Power Joint which was available with M10 one side M8 the other but they are not available anymore due to environmental regulations with the old process. They have since resourced with a European mfg but they are unavailable with M10 on M8 which will rule out the Europin version.

M8 and M10 Boge joints are available from Duotone dealers, they can easily be ordered.

Sunshine Coast Boardsports has the M8 versions:

www.scboardsports.com.au/products/uni-joint-boge?_pos=1&_sid=9c68552b2&_ss=r

As a side question , do tendons have a use by date ? I know rubber hardens over time .
I was just looking at a new one that I have in my garage , to change at Xmas as I do . It is still in its plastic bag and been stored in the dark . However it has jun17 moulded into the end of it .
Any rubber experts ? , should I spend another $25 on a newer one ?

^^ My only rubber tendon is on my Phantom 380 standard uni.. Thought most tendons were urethane? Boge hourglass style is rubber. Urethane Tendons do seem to have a useby date. Newer stuff not as good as the old gear.

I have e a brand new , never used , in original packaging 2017 tendon . Willing to trade with a 2019 model.

Imax1 Chuck a couple of bolts in it n crank it around. Load it up. If you see any cracks or odd bulging dont use it. Ive heard of a few n had one urethane type break when never been used. Rubber needs to be worked regularly to stay flexible.

Skip two meals at McDonalds and buy a new complete base. They are kinda important for your safety and cost nothing (eg $60 to $100).

Took me a while but eventually I found a company selling M10 one end and M8 the other end BOGE Joints.
Arrived in about a week from the UK.
They have an impressive range of spare parts.

www.wsurf.eu/power-joint-boge-type-10-m8/