For interest see this Article from 1984 May - June Freesail issue on "Choosing the Right Mast". I had the Windsurfer flexible "fishing rod" blue mast 1982, then the Gaastra Blue glass mast 1983 (snapped it about a year and a half later) then went in about 1985 to the Kilwell 4.50 recreational surf mast made in New Zealand. Things have changed , technology, quality, reliability, materials, durability and design has improved and masts cost a lot more today. Also we no longer have one piece masts which was the only choice in 1984, now 2 piece is the standard. Aluminium masts no longer exist. No longer do we have local mast manufacturers in Australia except for specialised companies like Slake.
Ampro grays were strong, heavy, one piece, and stayed cool.
When Killwell came out, the top didn't fit the camber sails of those years.
We all craved the Rotho Duo, no idea where they were made only ever got them secondhand from the UK.
Select to expand quotepeterowensbabs said..
We all craved the Rotho Duo, no idea where they were made only ever got them secondhand from the UK.
Had one and it was terrible. Didn't really matter what way round you put it 20mins 8n and it would of rotated itself back to soft flex.
Select to expand quotepeterowensbabs said..
We all craved the Rotho Duo, no idea where they were made only ever got them secondhand from the UK.
I think they were a German or Dutch company. They were imported by Barlow Marine as I recall. (who also imported F2 and TC) The Duo was certainly an interesting mast. I still have one hanging in a shed somewhere. I think it is a 4.9m or 5m mast and it is amazing to me now that I rigged a 4.7m RAF wave on it!. They usually stayed the way they were rigged for me, but I think doing the boom up tight helped, and this was pre clamp boom heads so that was not a simple matter. 
The best of the pre clamp boom heads I used were the REEF, but you could also crush your mast with them. 
There was also another contempory mast model (Exel?) that had Unidirectional Carbon tapes up on opposite sides of the mast that would change the stiffness depending on if you had them oriented to the side or front and back when rigged.
The early Kilwell masts did have quite a large diameter tip, but the later Carbon ones (Decrepit still uses in his modern sails - designed by Bugs?) were more tapered and close to the tip diameter of most others (but 46mm base diameter). Kilwell also made some of the early Gaastra masts.
The aluminium masts main issue was corrosion. They ate away from the inside. Once they had a weakness or a pinhole from this, they would break. I still have a couple of these (Serfiac) in the rafters of the shed too, but no way would I try to use them as they are full of pin holes. 
Select to expand quotesailquik said.. >>>
The early Kilwell masts did have quite a large diameter tip, but the later Carbon ones (Decrepit still uses in his modern sails - designed by Bugs?) were more tapered and close to the tip diameter of most others (but 46mm base diameter).
Yes Andrew, When Bugs (Phil Smith) was designing slalom sails for Hot Sails, back in the early 90s, he figured you couldn't win a race with a snapped mast, so he went back to the earlier, smaller, 46mm dia and increased wall thickness.
Kilwell sold them as Matrix 5s, Stuart Bell sold them as Carbon 70/90s?
These worked incredibly well, even as wave masts. I've had mine pole vaulted into the reef, standing vertical with the board hanging down, and broken waves washing over them. Snapped booms, harness hooks and torn harness webbing in crashes, but the mid 90s masts are still going strong.
Oh yes, they are 1 piece
Unfortunately for the windsurfing world in general, Bugs couldn't convince the makers of mast extenders and boom front ends, to accommodate the slightly narrower diameter masts. So they never caught on.
The medium diameter masts (MDM) might be making a come back. ??
my new 560 and 550 masts rig with an rdm extension with a shim. Happy so far with my first couple of sessions.
Hmmm.... I might have to talk to Kilwell about getting a sample made from their old mandrels! 
On second thoughts, shipping a one piece would be a buga'! 
I still have a Kilwell in my shed, it got mangled heaps of times in the Trigg shore break but proved indestructible. I wrapped some extra fiberglass around the bottom few centimeters because I had seen some crack there.
In my collection I've a 460 kilwell 46mm mast. Used it when I started back sailing. Also have a North aluminium blue anodised thing, its 3 piece with carbon top. Got the whole rig actually sail mast boom. Compared to todays gear its a hideous looking setup.
Sailed yesterday with 1995 Gaastra CS Pro 6.0. Rigged right next to a Duotone team rider on his '19 6.2 4 cam.
He was on Tillo and foil, me on X-cite 105. Both worked fine.
I do have 2018 Retro 6.0 in the van.
Those Kilwell Gasstra Cabon Pro masts were rubbish, they had no memory. After coming in from a day of sailing you would derig and the mast would retain the sails luff curve. 
Select to expand quotedecrepit said..sailquik said.. >>>
The early Kilwell masts did have quite a large diameter tip, but the later Carbon ones (Decrepit still uses in his modern sails - designed by Bugs?) were more tapered and close to the tip diameter of most others (but 46mm base diameter).
Yes Andrew, When Bugs (Phil Smith) was designing slalom sails for Hot Sails, back in the early 90s, he figured you couldn't win a race with a snapped mast, so he went back to the earlier, smaller, 46mm dia and increased wall thickness.
Kilwell sold them as Matrix 5s, Stuart Bell sold them as Carbon 70/90s?
These worked incredibly well, even as wave masts. I've had mine pole vaulted into the reef, standing vertical with the board hanging down, and broken waves washing over them. Snapped booms, harness hooks and torn harness webbing in crashes, but the mid 90s masts are still going strong.
Oh yes, they are 1 piece
Unfortunately for the windsurfing world in general, Bugs couldn't convince the makers of mast extenders and boom front ends, to accommodate the slightly narrower diameter masts. So they never caught on.
+1 ^ on Decrepit. I have destroyed countless booms, two-piece carbon masts and harnesses, but I still use my Kilwells one piece Matrix5's .... so over 20 years later, in my experience, they are waaay stronger, lighter and are by far the best masts I have ever owned. Every sail seems to rig better on them than on the manufacturer's two-piece mast. I am not sure if this is down to having no thick/stiff section at the join, ( there is a debate in itself right there!) but If Kilwell ever break out the mandrels to make another batch, I will be first in the queue.
^ Fangman,after reading your top rap on the ol Kilwell mast. You've got me thinking I might get that ol mast out for a test run. Only problem is I don't have the original spacer which was much thinner than the current model. If I remember correctly it was lucky if its 1mm thick. What's the solution?
Select to expand quoteolskool said..
^ Fangman,after reading your top rap on the ol Kilwell mast. You've got me thinking I might get that ol mast out for a test run. Only problem is I don't have the original spacer which was much thinner than the current model. If I remember correctly it was lucky if its 1mm thick. What's the solution?
olskool, I am not sure I know what all the bits all called - where/what does the spacer do? Is it on the mast foot extension or on the boom head or something else? 
Select to expand quoteolskool said..
^ Fangman,after reading your top rap on the ol Kilwell mast. You've got me thinking I might get that ol mast out for a test run. Only problem is I don't have the original spacer which was much thinner than the current model. If I remember correctly it was lucky if its 1mm thick. What's the solution?
It has to be a "matrix 5" to be what we are talking about. There were plenty of other kilwell masts that were OK, but not special like these.
And like Fangy, I don't know what spacer you're talking about.
I use a chinnok mast extender with the shims removed, that then fits inside the 46mm mast OK, and modern booms have no trouble clamping on the mast without any shims. Unlike older boom heads that were just too big.
Decrepit, agree our mate Bug's was spot on with the Kilwell M5 and being able to use a carbon race mast
to continue . to be able to use a carbon race mast in the waves was awesome.
I did break some early masts and went to the Killwell factory and got shown the mandrel and layups (interesting for board laminator at the time). I still use a M5 430 one piece and the fun of getting through an airport without hitting anyone or anything
The thinner wall 48mm carbon race masts were fragile and then using a fibreglass wave mast
I still have an old streamline extension which had the removable plastic shim so you could use both.
Some extensions won't fit into the Killwell masts.
I remember the aluminium masts and broke one in the shorebreak
Some broke when sailing and looked dangerous with a sharp jaggered edge.
When I lived in Canberra I remembered the Duo mast that would give more shape for the light winds.
Just order a new Slake mast. Comes complete with a shim for an rdm extension. Standard boom head fits ok.
They feel a bit heavier than an sdm but look bulletproof and rig sweet.
Easy and cheap shims made with PVC pipe. 
I cant see any reason why it should not be possible to make a two piece "Matrix5" with the right layup/materials that has absolutely minimal affect on the bend curve. Of course, with any join, it is possible to create a weaker point, but current two piece masts very rarely break at the join. 99% of mast breaks are around the boom area in my experience (on SDM's. I have never broken an RDM).
There actually may be advantages for slalom and speed sails by using a mid diameter mast. I think I need to investigate.
Fangy n Decrepit, mine is definately MATRIX 5 C70 1.9kg! made in NZ.
None of my Chinook sdm extensions fit inside it. The plastic cap at top of extension too large a diameter. Shim / collar which locates on pin on extension is also too big. Id send a pic but cannot do so with this Precambrian phone machine I currently use.
The original collar was much thinner where it slid inside the mast. Its long gone. Crushed it in the tailgate of my cruiser.
If I take the top cap off the extension to suit Matrix5 will it damage my normal sdm, due to it being loose?
Select to expand quote515 said..
I remember the aluminium masts and broke one in the shorebreak
Some broke when sailing and looked dangerous with a sharp jaggered edge.
When I lived in Canberra I remembered the Duo mast that would give more shape for the light winds.
The old aluminium masts are still useful. But first you have to break them, and then you can use those jagged edges as a scalpel.
There were also Seakite masts from New Zealand. Never had one but they were around in 1984 or so maybe they became Kilwell.
Kilwell has made top quality fishing rod blanks for a long long time. Hence the name????
Yes they are big in fishing rods.
Hey Olskool you been catching any fish?
cheers
Greg
Select to expand quoteolskool said..
Fangy n Decrepit, mine is definately MATRIX 5 C70 1.9kg! made in NZ.
None of my Chinook sdm extensions fit inside it. The plastic cap at top of extension too large a diameter. Shim / collar which locates on pin on extension is also too big. Id send a pic but cannot do so with this Precambrian phone machine I currently use.
The original collar was much thinner where it slid inside the mast. Its long gone. Crushed it in the tailgate of my cruiser.
If I take the top cap off the extension to suit Matrix5 will it damage my normal sdm, due to it being loose?
Well, you are stuffed!
I guess you dont have an RDM extension, but if you did, that would be the best option with a shim of PVC Pipe, and perhaps a base collar from a thicker piece of tubeSelect to expand quoteolskool said..
Kilwell has made top quality fishing rod blanks for a long long time. Hence the name????
And still do. Some of the biggest and best brands. 
Kilwell is very large in NZ in lots of other sporting goods.
Select to expand quoteRichardG said..
There were also Seakite masts from New Zealand. Never had one but they were around in 1984 or so maybe they became Kilwell.
Hmmmm? Does anyone have any more info on seakite?
