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Windsurf Mast Bases and Extensions

When I went over the parts of a windsurf board/sailboard discussed on this blog, i figured i had covered ALL the parts of the kit.  NOT.  There is always something that eludes us. And so , I discovered that i wrote little or nothing on the subject of mast bases and extensions. I started writing down some ideas and came up with WAY more than expected ... AND in 2017 , this STILL appears to be the MOST popular post on my "blog" !!!!

OK, let's get rollin' ....

Way back when , mast bases and extensions were proprietary. UNFORTUNATELY. I have some old long boards that when the mast base breaks, the board is NO LONGER usable #$%^&*() BIC, Mistral, Fanatic and surely others ALL had their version of the mast base. Many of the early extensions did NOT have pulley systems either.

Here is an example of the original Windsurfer mast base:

from HitTheWave
When the portion on the right ,which inserts into the board, breaks, one can no longer go out on the water. Fortunately this one looks like it is made out of wood and as such, can be replaced by a handyman or workshop. This is NOT always the case, as you will see below ...

Now let me post the pics of my early stuff:

BIC Dufour Wing had two(2) "holes" in the board where the mast base could be inserted. My plastic clips broke and I replaced them with metal cauter pins.

On the right you can see the mast base, extension and how I added the pulleys: I actually figured that part out myself. Local shop used rivets, but that did NOT hold. I use small nuts n bolts instead as seen in the picture below:.

With old mast base proprietary parts it is important to plan for the worst - loss or breakage and often people try to use the old connector with a more modern top connection for a standard mast extension !!!

The Mistral Equipe had a specialized bolt that locked onto the carriage on the mast track, which is depicted on the left. The "bolt" locks by twisting the red TAB. The base and extension are ONE piece which is not practical. At least the idea of a pulley system was started ....

The Fanatic Ultra CAT had a completely different mast track and base.

Once again, I felt I needed standard mast base for standard extensions and made the following adjustments:

Unfortunately this mast base had a "hook" on only one side and as such broke. Naturally I was able to glue it, but confidence was low on durability. 

Here is a picture of my mast base from what i called my BIC Samba. When it broke, i threw it and the water logged board out. At that time it was the best board for newbies up at the lake :-(

And so, the good news was/is that eventually a standard mast track was used on short boards, long boards, etc which allowed for a standard mast base...

from StarBoard
Even as I write this, I realize there are exceptions ... The mast base for sliding or adjustable tracks on racing long boards have a new standard base bottom:
isthmus sailboards

So, you can see that already many different concepts have been discussed here and there are many more to go. The base is NOT a piece to be overlooked. It carries or holds the infamous universal joint - non, not marijuana !! It is the rubber piece that made the mobile sail possible and as such - windsurfing !!!

The mast base has three(3) major parts. The portion that connects to the board - more or less standard now, the universal joint or a variation there-of and the actual base that connects to the mast extension . We have discussed the portion that connects to the board... One thing I have not mentioned yet is that not only is there a single bolt attachment, but there is also a two(2) bolt plate system that is used to attach the base to the board. It is not as flexible in terms of adjusting while out on the water, but never breaks and if one has a plate on each board, the boards can be interchanged very quickly .... Actually I just discovered that the bottom of the top piece in a 2 bolt system can be used to loosen and tighten the hex bolts !! And so, CAN be adjusted when out on the water !!! Also, one puts a plate between the mast base and the board - some plates like Nautix say they act as a shock "absorber". Mostly I guess the plate acts to not scratch the board as one tightens the base to the track...

And now for the universal joint portion. For quite some time it was typically the hour glass solid rubber version:

Not sure when or how it happened, the next step up seemed to be the narrow rubber piece called a tendon. This one seems to need replacement more often than the original hour glass version. It is good for slalom since it is stiff, solid and very mobile. Here is what it looks like.

And then eventually there was a version called the mechanical joint:

Personally I use this one for very wide boards - mine is 93 cm wide. The board can lie flat on the water with the joint angled at 90 degrees. Since typically large sails are used with wide boards, the large sail can lie in the water while the extension is attached to the base. Some people feel these bases lose less energy and may actually be faster !!! I have no data to prove or disprove that..

In 2017 Starboard starting using mechanical joints on their WindSUPs as they put less stress on the board when the sail is lying down in the water ...

In the past the extension was often part n parcel of the mast base. Now we need to down-haul with some force and as such it is impractical to have the base attached permanently to the extension. Instead there are various ways of attaching the base to the extension. The two(2) most common are called U.S. and Euro pin connections. Currently it seems the Euro pin is gaining popularity. With cold hands the U.S. cup is often more difficult to remove. Remember , we do NOT want anything to come apart too easily since it MUST all remain together on the water !!!


As you can see in the image on the left, the U.S. system is with two(2) pins that are compressed at the same time in order to release. This connection is solid and has no issues with sand or dirt. What does seem to happen over time is: the "holes" on the extension seem to enlarge over time and allow for some movement. As already mentioned, this connection is sometimes difficult to remove with cold hands. If the two(2) bolt system is used, there is an alternative way to remove the base ...


This one is the Euro or European pin. It snaps onto the mast extension and releases easily with one push on a button. For cold hands some people swear by them. Some people warn about getting sand and/or dirt in the connection. People suggest that the uni MUST be machined from one piece of stainless steel. Names like Chinook, Streamlined and Severne are batted around as being the BEST and most ROBUST. As mentioned earlier - this is NOT a piece of equipment you want to have issues with on the water $%^&*()

Now that we have discussed the "standard" mast bases with some minor exceptions, let's look at the other exceptions !!! Some companies have begun to incorporate more serious shock absorption in their mast extensions!!  The North base is called North SHOX XTR and has been around since about 2009. Naturally it requires its own proprietary base !!!..

North Sails seem to have a few other different connections as well !!!

2013 NorthSails Extensions from mpora

Extension Pins from Boardseeker
The one on the left is the Neil Pryde/NP Power MXT (Mono Button Mast Base System). Again proprietary !!

Why are these companies making so many different options. Once you lock yourself in on one, you are stuck. They better NOT change it afterwards #$%^&*()_

In terms of materials ...  the nut at the base of the mast base is typically made of brass. My understanding is that this is to reduce rust and corrosion potential - especially from salt water... On one of my mast bases the portions that attach to the tendon are made of metal. This should NEVER crack or break. Somewhere in this discussion i mention that the Euro pin should be made from one solid piece of stainless steel. Tendons and parts need to be verified to ensure NO cracks or issues and replace as necessary !!! In case of issues, mast bases have safety lines !!

One company that seems to have very solid mast bases {and extensions} is "Streamlined". Unfortunately they are NOT available in Canada...

So , let us review the modern mast base options before discussing the mast extensions...

Summary: Modern windsurf or sail boards have standard mast tracks with a different standard on the race long boards with sliding mast track. For the standard mast track there are the single bolt and two bolt plate options. With the two bolt plate you lose just a little bit of mast base placement on both ends of the track - about 2 cm. The universal standard is the hourglass, the tendon and the mechanical joint. For an average joe windsurfer like myself,  I feel NO difference on these options. At the top of the mast base the standards are U.S. cup/2 pin and Euro pin. The exceptions in the middle of the mast base and at the top are NP and NorthSails/NS.

...And now on to the mast extension discussion...

Once you have chosen your mast base for your board, you obviously have already made your choice in terms of mast extension connection, as they MUST obviously fit WELL together !!! We have already seen that today NP has their own MXT system and North has their SHOX system. The rest are U.S. cup or Euro pin...

In case you did not know, there are SDM and RDM masts. SDM is standard diameter and RDM is reduced diameter. Luckily the same mast base can be used for either SDM or RDM mast extensions.

Extensions are made of aluminium alloy or carbon. Carbon is obviously more money and actually more fragile. Personally i have rarely seen people use carbon mast extensions !!!

Mast extensions come in various lengths and few are available with zero downhaul. Typical lengths are 12, 28 and 42 cm. Some people say one should use the shortest extension needed and not more. Others like myself, simply purchase the 40 cm extensions and know we are good to go !!! There are some extensions available as long as 48 cm. There are also 40 cm carbon mast extenders. Some people like myself are NOT so sure about such beasts. It changes the mast curve and may place stress on the mast for boom, cambers, etc on areas that were not designed for that !!!

Mpora or boardseeker did a mast extension analysis recently and i will put a link here and use the article as a base for this discussion ... The article has good comparison criteria, butt the link to the test results does NOT work #$%^&*(

The parts of a mast extension are as follows: rope, pulley, extension itself with different length settings, clip or pin to change length, and cap at the top. At the right is a Chinook extension which seems to come with no rope/string. I use the Spectra down-haul rope that costs about $1 per foot and put about 6 feet on each extension. 

Where it says base is where one connects the mast base. One extension i had - the plastic base cracked.I believe the reason for that was the pulleys were incorporated into the plastic base. I put electrical tape around it and keep it as a spare ...

There are variations of the adjustable collar and there used to be versions with a pin. Even if the pin comes attached to a string, it feels impracticable. Now it seems all the companies are going with variations of the clamp-on collar - all in plastic from what i have seen.

One of the issues with extensions is the measurements.The distance from pulley to sail pulley is NOT the same extension to extension. Just as not all 490 cm masts are 490 cm !! It is important to double check the measurements. They used to go in 5 cm increments, but i believe they are practically all in 2 cm increments now.

The biggest differences between extensions seems to be in the pulleys. Streamlined actually offers bearings inside the pulleys - for an extra fee of course. The pulleys vary in alignment , size, etc. Personally there are two(2) extensions i would like to try - the NP UXT and the Streamlined extension with bearings. Both of these are NOT readily available in Montreal, Canada. Since i do not have many videos in this post, I will put one here of Rik with a NP UXT (universal extension)... And now videos are disappearing on the web $%^&*( I download fotos to avoid this issue - now will do the same with videos !!!

Neil Pryde UXT Evo Mast Base System from RiksWS on Vimeo.

Well, here is a photo:
Those pulleys are aligned so as to be as close to the sail pulley alignment as possible. Some pulleys are at 90 degrees to the extension and others are parallel, making it necessary to follow a certain methodology so as NOT to overlap the lines.. They also say bigger pulleys allow more force ...

One thing that is ODD is that most sails rig with the mast on the right. This means the pulley system is set up to rig to this sail. However, there are once again exceptions. I have not yet discussed Severne. Not only do they rig with the mast on the left, butt they also have more pulleys on their race sails. This obliges you to purchase their masts and extensions to match the sail. Personally I find this inconvenient and a deterrent for people to switch to Severne !! Let's try to be consistent brand to brand and universal !!!

This video looks like it describes the above mast extension:

In Sept 2014 I managed to take my old Mistral extension apart and this is what it looked like ...

North has about the only system which can be considered adjustable downhaul on the water. You still need to stop and get off, but it is do-able. Also, there is NO muscle or major pulling required whilst cranking the downhaul... Since this is from North-Sails, i anticipate this video will NOT go away !! Personally find all these cranks a bit expensive. Even a manual crank is about $40 +

and here is the North Sails SHOX system which is to be like a shock absorber ...

In terms of threading a mast extension with the sail ....
The post on masts contains my explanation

and here is another:

Have discovered that there is NO RDM 48 cm extension UNLESS one purchases the carbon version. People are saying non-carbon version  is available, but NONE in my town ...

There are plenty of downhaul tools or people loop the rope around an object and pull from there. People have hurt themselves with screwdrivers and hammers doing this.The worst I have heard is twelve stitches from using this plastic downhaul tool ^&*()

Here are some acceptable downhaul tools. I have had issues with one where the clamp clew was only on one side - suggest always using one with them on both sides ..

David Ezzy shows us how to safely loop the rope in order to downhaul with what we have about:

In 2019 StarBorg is releasing a mast extension that will work with SDM and RDM ...
what if very little extension is required - like 5 cm or less ??

In 2018 I tried a Reix Competition D2/DIV2 , but the mast base separated from the board and I the board $%^&*() Also spent two(2) damn hours in the cold water before being rescued. Afterwards people told me that one should attach the mast base to the board so they would NEVER come completely apart .

Oh well - no more D2/DIV2 for me unless it has a track ...

Did find a Lechner 390 missing its mast base and so asked on facebook what the mast base looks like - looks like NOTHING I have seem before - so, unless one has the base a DIV2 is useless ??

SAD and THAT is why i HATE proprietary mast bases #$%^&*()_

In 2018 I also a Tiga Fun Cup for sale/sail, but when i look up how the mast base looks = NO WAY.
This one is busted, but even the base looks like it needs some TLC !!

OLD proprietary CRAP $%^&*()

Well, here we are in December 2021 and I am still learning about the mast base parts ...
This here is an adapter which allows you to have a Euro pin mast base and US type extensions !! Makes the conversion from US cup to Euro pin so much less painful in $$$
However, as we are in COVID times and windsurfing is dying in North America - they are nowhere to be found except perhaps loopee !!
Please accept my apologies for NOT answering all the questions in the comments

Parts are definitely getting more n more difficult to find
and you may have noticed I do HATE proprietary connection pieces $%^&*(

Summary of 2013 Summer Windsurfing

In the title I include the word Summer since I do windsurf in the winter on the ice as well. Snow has NOT been as successful, butt ok in less than 3 inches of snow - especially if snow is on the ice...

It is now November and it is starting to feel like we are between seasons. Unfortunately that also usually means I become aware that i gained weight and the jogging needs to start #$%^&*()

My limit for wind speed is still somewhere just over 20 knots. I do NOT have enough opportunity to practice with my smallest sail , HotSailsMaui 6.3 Fire, on my smallest board, Fanatic BEE LTD 124. On the other hand, I was getting VERY comfortable with the long board, Fanatic Ultra CAT of 210 liters. In fact, I was SO comfortable with that board, that i did NOT use the BIC Techno Formula of 94 cm width. That may also have something to do with the fact that the MauiSails TR-6 10-oh sail needs a repair at the top. I have a work-around, butt never tested it on the water. May actually have found a better fix. Barry Spanier of MauiSails feels this other fix is viable.

A TR-6 8.4 race sail was purchased to replace the defunct MauiSails MS-2 8-oh. This is a GREAT sail, but i have a difficult time uphauling it and so I put the MS-2 back in commission. It has monofilm repairs and no more cambers. When there is a bit too much chop I use the MS-2. I made a good film with the TR-6 and posted it on youtube. Was filmed with the GoPro 1.0 that i purchased end of 2012...

The CAT was so much my favourite GO TO board, that i was extremely disappointed as it got scragglier and scragglier... The mast base was glued and i catapaulted resulting in a hole in the nose. And so , I looked for a replacement and ended up with a Mistral Equipe I LCS-XR. This board has NOT disappointed and so far I almost like it more than the CAT !!!

The AHD FF 160 is still a GREAT board and LOVE it with any 8.x sail in about 16 knots wind !!! Feel like i will never sell it !!!

I now wear shorts over my wetsuit - like a kiter. This holds my van key securely.

My booties for the summer are dead and i use my winter booties... My winter boots are NOT warm enough. Windspirit has some boots that interest me ...

Took four (4) newbies out for sessions this year. Mostly with the BIC Techno Formula. They did NOT like the long weed fin that stuck out the back. Told them they could buy me a shorter one for about 30 bucks since i did not need one :-) Some of them also preferred my North Sails Zeta 4.x over the HSM Fire 6.3. One fellow is stoked for sure and will be back !!! He is planning to practice in Morocco - lucky dog !!

Somehow managed to spend $1100 this year - with the 8.4 race sail, Mistral Equipe, harness lines, mast bases, OKA pass, etc. Was also looking at a Kona ONE in great shape... At $1400 i offered 1200 and was refused. Purchased the Equipe instead. When the KONA was at $850 {even with the Equipe in my quiver}  i tried to sell my BTF , butt fell through. A fellow on iwindsurf has Equipe carbon, BTF and Kona One Carbon !!!

So far this year {will try to go out ONE more time !! } I have windsurfed approximately 68 times. Over 85% of my sessions were with my 8.x square meter sails. From the board perspective, over 65 % of my sessions were on a good longboard - Fanatic Ultra CAT or Mistral Equipe. In terms of sites, 44% of my outings were at OKA Parc where the vast majority were at La CrĂȘtre - which was closed last Sunday %$^&*(

Next year: good life jacket to learn water starts once and for all. Will make NO promises for foot straps. Someday will get a used 8-oh with NO cambers OR learn to deal with the TR-6 8.4 properly !!

Quiver Analysis: If I bring the Mistral Equipe I LCS of 210 liters, the AHD FF 160 liters, Gaastra Flow 3X 7.0 & MauiSails TR-6 8.4, I will cover 99.99% of the sessions I had in 2013. That is a two(2) board and two(2) sail quiver. However, did NOT use the BTF/BIC Techno Formula with the 10m sail myself. Hope to remedy that situation in 2014. Even with those two(2), it would be three(3) board and three(3) sail quiver ... Problem: The van is getting older :-(

Summary: NO issues in equipment coverage for the year. Just need to improve the technique !!!

01NOV2013 too much wind ?? 30 to 50 knots !!!

When I saw that there was going to be a rise in temperature on Friday and more wind i became exited. And then I SAW !! They were announcing OVER 30 knot winds ... One of our windsurf buddies said we needed extreme sport diapers to sail in those conditions ...

Naturally power was lost in over 50,000 homes within one hour of the winds starting.

Some of the pros went to SBX/sandbanks and some stayed local at OKA. I stayed home !!

Here are some photos people referred us to from quebec wind...

On one of the forums I felt a fellow windsurfer said it well," Too much wind for us is as bad as not enough!" However, for some, these winds just put a smile on their faces !!!

Naturally there are big waves, and all kinds of antics NOT usually seen in our neck of the woods... People were OVER with sails in the 3.0 to 4.0 range !! FREEWAVE sounds like the name of the game !!!

Photo sources: