Tag Archives: marblehead blog

Calibrate Your Backstays, Anyone??!!

When HS and I raced our International Dragon over at Medway Yacht Club, we were forever adjusting our backstay tension… just like radio sailing. Calibrating the rig so you could see and record what you were doing was just as vital – on backstays, …not as easy as it sounds!!

So for the same reasons, we constantly adjust backstays in radio sailing. What is a way to know “where you are” with your adjustment?

I was lucky enough to get a new IOM from SailboatRC last October. I’m only just getting to use it really. I bought the version of their package where the factory sets up all the rigs for you too. (Not that you’d notice in my results – ha ha !). On the three rigs (A,B,C) when they have the backstays set up correctly in the factory they run a fine black pen over the lines leaving you with a black dot on both sides of the loop. So line up the two dots, and you are back to where the standard factory setting – “voila”, I thought !!

The thing is that inevitably the owner, and at Datchet all the experts who come to help(!)… all have a tweak of the backstay. It’s quite difficult to see it clearly whether it’s your own hand on the bowsie in the way, or someone else’s.

So I went down to the stationers and bought a very fine permanent red pen plus the same thing in black. Now look at the photo above :-

On the bowsie side of the adjustment loop, I marked the factory dot in red colour. It is on the right hand side of this photo. Then I took the black pen and a ruler and placed, for now, a black dot 1cm above the factory mark and a second dot 1cm below the factory mark. It’s a 2:1 adjustment of course, but now I can see half a cm above and below the (centre) factory mark. I suspect I might have to add a further two dots, making five in total, but let’s see how we go.

Can You Cut Dyneema Line with Kevlar Scissors??

Just recently we published a couple of items on both dyneema line sizes and cutting them with dyneema scissors.

In my experimenting here, I happily got my dyneema lines out to find if there is any need for fuss about cutting it… there is!! My Stanley knife and scissor collection was useless.

I immediately googled “dyneema scissors” on Amazon and got the fright of my life … £40-£60 for a pair of scissors!! Tut tut NO!!! I noticed that kevlar scissors were about half the price, and so googled “can you cut dyneema with kevlar scissors?” and this interesting little video came up:-

You can never tell if these videos are genuine or not, can you? Anyway, I found on Amazon the exact Kevlar shears they use in this video – £20 !! Ordered a pair and they are great!! £20 sounds a lot, but at local coffee prices that’s only about 6 flat whites, and they’ll probably last a lifetime. I’m happy!!

It seems that a reason there may be so many kevlar shears out there to choose from is that this is the method of choice for cutting fibre optic cable. Who’d have known the big need for that ten years ago!

I’m less happy about sealing the rope-ends though. I’m using a keelboat rope burner from my toolbox at the minute – very quick, but leaves a bit of a blob. Might be OK. Sailboat RC recommend a quick swipe of THIN superglue along the line, cut it with your wife’s favourite ceramic kitchen knife, and then you can thread it through holes. I have a battery sealing knife in my toolbox – I must have dropped int once too often as it refuses to deal with dyneema or anything else at the moment. SailboatRC list a natty little USB plasma cutter – only 15 euros… but postage is 49 euros!! More research to do!

Cord Sizes – What to Carry in Your Tool Kit !!

Rather impulsively, in 2023, I decided to make a move into Radio Sailing. Practically nothing worked in my big boat toolbox for this part of the sport. Evidently none of my (huge) string and cord collection was going to work . In the flash of the moment I acquired a reel of dyneema to be ready for anything, or so I thought.

That’s it in the photo above. The experienced amongst you will spot my error straight away. It’s a 300m reel – that’s enough for a whole club fleet to use for a hundred years.

It is also 4 braid which gives it a slightly lumpy appearance – I know now that SailsEtc recommend 8-braid lines.

If you have come to radio sailing from another branch of sailing, you’ll realise that you use different size and strength lines for different jobs on the boat. In your first encounter, you may think that all the lines we use are the same size (small).

Not so – explore SailsEtc and try looking at the Sailboat RC website. Sailboat RC carry a stock of four grades of lines – if you buy from them, they come on different colour spools about the same diameter as 5p piece or smaller. In a crowded tool box that’s a good idea, but I’m also thinking is using different colour lines to indicate diameter or strength is a good way to go – see SailsEtc.

This is what Sailboat RC says:-

GREEN spool   0.25mm 18.5kg Topping Lifts

BLUE spool 0.30mm 36kg   Main&Jib Sheets

LIGHT GREY spool 0.70mm 60KG  Drum Sheets 

                                                                        &Jib Foot to magnet    

TRANSPARENT Spool 0.70mm 30kg Rigging all round

The diameter is interesting, but not half as interesting in the line loads indicated for each job.

Generally speaking they only put around 5-10metres on a spool, and frankly that would last a club sailor a lifetime. At that size, you can tuck them anywhere in the toolbox.

If anyone needs 300m of dyneema, give me a call!!