Well this is what 4++months without a sail due to a broken foot does to you !!

I Decided to make a slightly longer fuselage for my RSX foil - to bringer it closer to the starboard race after a lot of reading ... original intent was to make a fuselage to replicate the race and I bought a piece of 33mm diameter aluminium .. but it was only 1m (not1.15m) so had to adapt!

Plan was to start with the round bar and machine a taper to the rear wing with two flats machined for wing mounting

My dad has promised to do the machining but wanted a drawing 1st...




Should get machined this week then anodised next week... hopefully by then I get the doctors ok to sail again !

Updates to follow

nice project, keep us updated with plenty of pics !!!

Interesting project mate, I'll be intrigued to read your results. I lengthened an F4 Fuselage 300mm (initially lengthened it 115mm), seen below next to a Starboard race foil. The stability difference is massive, foil gybes are way easier and it's more competitive with the Starboard race foils upwind.

What grade of Ali did you buy?

Cjw - awesome work ! Agreed Everything I've read suggests Longer fuselage gives better stability so good to hear your experience reinforces this.

Peter - Material i bought is 6061 T6 - might not be best material but ok is a trial.

Sean - hopefully a few pictures later this week !

Adam

Is it inappropriate for me to say I have fuselage envy?

(btw, having taken drafting in school, props. My drawing would have been on the back of a grocery receipt)

This is an excellent thread, some top work here. Well done !

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Adam555 said..
Well this is what 4++months without a sail due to a broken foot does to you !!

I Decided to make a slightly longer fuselage for my RSX foil - to bringer it closer to the starboard race after a lot of reading ... original intent was to make a fuselage to replicate the race and I bought a piece of 33mm diameter aluminium .. but it was only 1m (not1.15m) so had to adapt!

Plan was to start with the round bar and machine a taper to the rear wing with two flats machined for wing mounting

My dad has promised to do the machining but wanted a drawing 1st...




Should get machined this week then anodised next week... hopefully by then I get the doctors ok to sail again !

Updates to follow

Nice design drawings Adam, did you find your drafting pens?

Yes indeed ! But looking forward to getting my sailing shoes back on ... still another month according to the doctor

By way of an update - machining has started ! Dad wasn't that well last week so delayed kick off

Plan is to mill and drill the two flats for the wing mounts 1st in the milling machine, then the wedge slot for the RSX mast. After this we'll machine the tail taper in the lathe ie 33mm down to 20mm diameter over about 500mm of fuselage length

Pictures show Front wing mount area with multiple holes to allow some fore/aft wing positions


Ive also realised the vertical spacing between the front and rear wing now will be 17mm verses 27mm originally because were maxing to get sufficient flat surface from the round to mount the wings .... anyone have any thoughts in terms of effect of the flow from the front wing on the rear stabiliser if too close to parallel ? Is isn't a big deal as can space up with 10mm packer on rear wing but would like to avoid this ideally ..

Will hopefully get a few more pictures through later this week ...

Adam

Machining of the slot for the mast underway.

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Adam555 said..
Machining of the slot for the mast underway.

is this your shed or dads?

Looking good mate! I was fortunate enough to have a CNC at my disposal but the little mill is doing a solid job

On the wing spacing I think it will be fine. The stagger on the F4 is quite small due to the bayonet style rear wing mount...the Starboard race is also a similar distance.

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CJW said..
Looking good mate! I was fortunate enough to have a CNC at my disposal but the little mill is doing a solid job

On the wing spacing I think it will be fine. The stagger on the F4 is quite small due to the bayonet style rear wing mount...the Starboard race is also a similar distance.

CJW thanks good to know re wing spacing. Is going well but slot taper will be by hand most likely

Yes Dave is old mans shed - once he retired he's really set himself up most of the time he's been building his trains .. check this out .. about 2years work from scratch 100% scale working steam train ..bit over a metre long

I would just build up the area with weld that you need the extra material thickness.
then machine the spacing you need.

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RAL INN said..
I would just build up the area with weld that you need the extra material thickness.
then machine the spacing you need.

Thanks Ral Inn.

FYI few more snaps coming along nicely.

Mast mount slot

Machining tail area

What will it weigh?

Guesstimate 1.8-2kg

Great work Adam

im not a foiler (yet), but a question to those that are: is the natural progression to separate the wings onto 2 separate masts, enabling greater separation (same as lengthening fuselage)? Fuselage disappears altogether.
yes, more weight, but load will be spread better across 2 boxes

Edit: no, because rear wing is behind tail of board?

It's be tried before. the current twin foils finally "appears" to be the system which works best for our style of watercraft

To date most of the lengthening of fuselage has been in order to position front wing lift further forward while using the original Tuttle box location on existing boards.
most companies have just left the length of fuselage rear of mast as is.
maybe more to do with the simple way to change a cad drawing?

a longer fuselage gives better yaw stability and so does the effectiveness of the rear vertical stabilisers.
Also longer fuselage equals more drag as does more Vertical stab.

but the rate of increases in drag will vary along with the efficiency of the profiles.
I see this as a big area of future design by those companies that push forward foil design.

the mast is a necessary evil and besides something to push against when pumping, it is just drag.
So having more than one mast and more than one part breaking the water surface tension layer makes no sense to me.

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Stretchy said..
Great work Adam

im not a foiler (yet), but a question to those that are: is the natural progression to separate the wings onto 2 separate masts, enabling greater separation (same as lengthening fuselage)? Fuselage disappears altogether.
yes, more weight, but load will be spread better across 2 boxes

Edit: no, because rear wing is behind tail of board?

Remember, the force on the stab is down, not up in most cases. Only the front wing is supporting weight. Having two masts wouldn't help because you'd have all the drag of two masts but only one is really doing any work.

Thanks for the feedback and sorry for crashing your thread Adam. It is interesting to learn a bit about how these things work

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Stretchy said..
Thanks for the feedback and sorry for crashing your thread Adam. It is interesting to learn a bit about how these things work

No issues mate - looking forward to you and Dave getting foiling..

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Te Hau said..
What will it weigh?

Checked today - original fuselage 0.8kg new one currently at 1.85kg before tail matching, have tweaked design a little to pull a bit more weight out of tail section by making parallel rather than tapered- hopefully gets machined tomorrow.. pictures to follow

Latest pictures below

shows taper post mast wedge slot 33-23mm diameter for tail section

RSX Mast fit up ... was done by hand to make sure the wedge fit was tight

Tail section

Haven't weighed it get but given 60% has been reduced by 30% ... should be around 1.5kg
Inserts to make next (plus perhaps slighter pointier front) and off to anodisers when am back from current work trip

been away in Congo for work for last 10days hence no progress snaps - see below - trial fit up today








Note extra length verses original fuselage!

Off to the anodisers next for a jet black finish and will post completed fuselage late next week .... here's hoping I get ok to sail next week from Physio

Adam

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Adam555 said..
been away in Congo for work for last 10days hence no progress snaps - see below - trial fit up today








Note extra length verses original fuselage!

Off to the anodisers next for a jet black finish and will post completed fuselage late next week .... here's hoping I get ok to sail next week from Physio

Adam

Nice work hope you get out on this very soon.

Ok all finished & anodised 25micron. Installed the s/s inserts today with the loctite 243 hopefully limits the inevitable galvanic corrosion. Also put some short cap head screws in the unused threaded inserts

Nice one Adam it will be nice to see how it goes

Yes a lot more work than I 1st thought lying on the couch! but really happy with result - my old man did a great job machining it

absolutely hanging out to go for a sail...Physio thinks another few weeks though with the broken foot...as soon a I test I'll post something !