Hi,

I am looking at a new sail that recommends a 400 rdm mast and a 166 boom.

I have sdm gear so far and don't really want to also buy rdm mast and extension etc.

Also my boom is minimum of 170cm.

Would appreciate any advice/ thoughts on rigging the sail on an sdm mast and my current boom, which is 4 cm longer than the recommended boom size.

Here is the sail - www.naishsails.com/product/sprint
I am looking at the 5.2

Thanks.

Select to expand quote

Bluefusionman said..
Hi,

I am looking at a new sail that recommends a 400 rdm mast and a 166 boom.

I have sdm gear so far and don't really want to also buy rdm mast and extension etc.

Also my boom is minimum of 170cm.

Would appreciate any advice/ thoughts on rigging the sail on an sdm mast and my current boom, which is 4 cm longer than the recommended boom size.

Here is the sail - www.naishsails.com/product/sprint
I am looking at the 5.2

Thanks.

make sure the sail is SDM compatible, some norths and Ezzy sails are. A lot of sails out there are only rdm so they have a narrow sleeve.

Perfect - I didn't know that one thanks

I wouldn't think so when the web link above shows 5.2 is RDM and all the others are SDM. Sounds like they designed the 5.2 differently
Ask the dealer, they will know. Boom would be fine

Thanks Mark

Select to expand quote

Bluefusionman said..
Hi,

I am looking at a new sail that recommends a 400 rdm mast and a 166 boom.

I have sdm gear so far and don't really want to also buy rdm mast and extension etc.

Also my boom is minimum of 170cm.

Would appreciate any advice/ thoughts on rigging the sail on an sdm mast and my current boom, which is 4 cm longer than the recommended boom size.

Here is the sail - www.naishsails.com/product/sprint
I am looking at the 5.2

Thanks.

Just another perspective.... Why choose the Sprint if it doesn't fit your gear? The SDM mast may work but what mast is it? Naish lean towards the Hard top side of constant curve so that will be important. Also, if the Naish boom length is 166 that may be the max setting so when you put some draft in it could be 160? That would leave a 10cm gap & that gets pretty wobbly. So unless you have a very compelling reason to choose the Sprint & depending on your existing mast bend curve, I would look elswhere. Surely there are plenty of other sails which would fit your equipment. On the other hand if you are really sold on the Naish - bite the bullet & get another boom at least to rig it properly.

Thanks gorgesailor. All good points.

I have the 7.2 Sprint and it's great. Not sold on the 5.2 just that it is going for a good price and I know it's a great sail.

I will probably let it go and keep looking for something else that fits better as you have suggested.

I'm new to the sport what's an rdm and sdm mean

Hello, dreamsailing,

RDM and SDM refer to the mast diameter. SDM stands for Standard Diameter Mast, whilst RDM stands for Reduced Diameter Mast. Originally, all masts were SDM but RDM's have taken over in the smaller sizes mainly for durability.

My SDM 430 mast, at its base, has an outside diameter of about 52mm and an inside diameter of about 48mm. My RDM 430 mast, at its base, has an OD of about 38mm and and ID of about 33mm. You can see that each mast will need a different diameter mast extension (never fit an RDM extension inside an SDM mast because the mast will break due to the loose fit of the RDM extension). Also, sails specifically designed for RDM's have a smaller luff sleeve and cannot be fitted with an SDM mast. Some sails have a luff sleeve designed for both SDM and RDM masts, so will take either mast.

Hope this helps.