Topic: Fairey Huntsman Power (Read 36784 times)

Stavros · « **Reply #50 on:** May 20, 2008, 10:14:45 PM »

Allright just for you I will put my hand up the MTB in question was mine it ran 2x Mfa850's a 12 7amp lead acid and yes it went a lot faster on the 12v 5amp batt.Run time for the 7amper was around 15 mins flat out, the 5amper around 10mins.
I have got a Hunts,am 49ins fiberglass and when I get around to it be fitting a pair of 700bb turbos both running 18v with 4x9.6 buggy packs it should fly running time wise havnt got a clue till I do it.

Stavros

Shipmate60 · « **Reply #51 on:** May 21, 2008, 09:00:14 AM »

The Gell Cell is still a good battery as long as you dont expect it to produce heavy current for long.
The 700 BB Turbos are well within the fast electric set up.
But motors such as MFA 850's only rev max 9000, but besause of their physical size are able to produce quite a lot of torque so a larger prop is well within their capability.
It is horses for courses really, stunning performance has a cost, the compromise is for acceptable performance/run times against cost.

Bob

Philipsparker · « **Reply #52 on:** May 28, 2008, 08:57:40 AM »

Update:

Now I'm back from holiday I have replaced the punny 2 blade plastic prob with an 80mm diameter four blade brass one. If nothing else it looks a lot better.

Tests on our 15ft garden pool indicate that the boat shifts a lot faster - but I need to get it on some proper water to judge. I doubt we are on the plane yet but it might be fast enough for me. If not then a faster motor is the next stop.

Phil

Philipsparker · « **Reply #53 on:** May 29, 2008, 10:31:56 PM »

We've now had a sail on the boating lake and the boat is a lot faster but still not quick enough. I've posted a video on my blog:

http://philsworkbench.blogspot.com/2008/05/not-quite-so-slow-huntsman.html

Next stop will be the motor shop to get something without that annoying, whinny, gearbox !

Phil

Martin [Admin] · « **Reply #54 on:** May 29, 2008, 10:59:13 PM »

OK, daft question time here:
The real Huntsman's, how fast are they?
( Not the racing ones, the run of the mill ones. )
What should the ride angle be?

Have a look at this video - the man talks an awful lot of sense!
http://www.youtube.com/watch?v=-jDJ9oKPrP8&feature=related

HS93 (RIP) · « **Reply #55 on:** May 29, 2008, 11:14:46 PM »

This sort of angle

peter

Shipmate60 · « **Reply #56 on:** May 29, 2008, 11:24:49 PM »

Phil,
That is running on about 2750 rpm, and yes what a whine!!
MFA 800's run about 4000 rpm so not much improvement.
MFA 850's run about 9000 rpm on 12 volts.
850's will give about 3 times the revs, but I am unsure about turning that big prop.
Might be worth trying to borrow 1 and try it.

Bob

Philipsparker · « **Reply #57 on:** May 30, 2008, 09:59:21 AM »

The good news is that Howes have an MFA 850 in stock and I've found at the bottom of the boat bits box a Sea Rover 15A speed controller.

So I'll be taking the shaft to Howes later today to see what they can do. According to the guy on the 'phone they have the moter & coupling bits in so I'll see what I can do. I have the two blade prop as well but it never seemed to "bite" on the water. However I will try it with the new motor once fitted. The existing motor can go in a tugboat or coaster some day where it won't be required to spin the prop so fast - it's never worth throwing anything away !

Thanks

Phil

Stavros · « **Reply #58 on:** May 30, 2008, 10:04:50 AM »

Phil woah the 850 WILL NOT throw an 80mm prop,max55mm 2 blader,and sorry but a 15amp speed controller is a big no no 20 amp minimum

Stavros

DickyD · « **Reply #59 on:** May 30, 2008, 10:46:42 AM »

From Howes web site.

Product Name Torpedo 850 Motor
Manufacturer MFA
Full Description
Torpedo 850 Motor
Large 12V motor ideal for the President Perkasa and Huntsman.
Speed 9778 RPM.
Size: 70mm long 50mm diameter.

Shipmate60 · « **Reply #60 on:** May 30, 2008, 01:19:27 PM »

Phil,
Sell the Deccaperm on here, always a good market for them, dont know why.

Bob

Shipmate60 · « **Reply #61 on:** May 30, 2008, 01:58:16 PM »

MFA 850 on eBay now:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=150251100333&ssPageName=STRK:MEWA:IT&ih=005

Bob

Shipmate60 · « **Reply #62 on:** May 30, 2008, 02:24:49 PM »

Or bite the bullet and go brushless like LifeboatPaul has on his.
A bit more expensive but good performance.

Bob

Philipsparker · « **Reply #63 on:** May 30, 2008, 06:05:51 PM »

Too late - I have an MFA 850 from Howes. And a battery. And the bits to watercool it (can anyone give any instructions on this, where the inlet & outlet go for example). And a coupling. And some other bits. And a broken R/C surfer for another project.

And a swollen tum from a stop at the Harvester on the way back to the M40. I'm too full to any modelling at present. Good meal though...

Phil

DickyD · « **Reply #64 on:** May 30, 2008, 06:25:45 PM »

Hope the photo might help with the water cooling. The inlet is about 12mm from prop and slightly off centre in front of the prop.

I have also shown you what type of inlet and outlet I have used.

Shipmate60 · « **Reply #65 on:** May 30, 2008, 09:11:15 PM »

Phil,
I would just try her first without water cooling.
From cold if you just slowly open the throttle full to see if she reaches the performance you want.
The water cooling will only be used for prolonged running, not a quick burst.
It saves cutting the hull in case you dont need to with your chosen motor.
Do you have any 7.2 batteries that you can connect in series making 14.4 volts?

Bob

Philipsparker · « **Reply #66 on:** May 30, 2008, 10:48:45 PM »

I'm going to start with 12V as that's the max the speed control can handle. I'll take the advice about the water cooling though for the minute. Tripling the RPM ought to make a bit of a difference.

Update as soon as I've stuck all the bits together.

Phil

Bradley · « **Reply #67 on:** May 31, 2008, 06:29:24 PM »

Phil,
If you go to eBay and put in Emax as a search it will come up with lots of these outrunners at different sizes. The ones on Paul's lifeboat are BL4030/10 and speed is quite impressive. I have just ordered two - BL2826 - which are slightly smaller but, I hope, powerful enough for a Mersey. The details given on eBay for each motor refer to their suitability for model aircraft but that gives you some idea of the power they put out.
Derek.

Philipsparker · « **Reply #68 on:** May 31, 2008, 07:00:47 PM »

As I said - too late - I have the 850 and it's now fitted. If the "found in the bottom of the boat bits box" speed control hadn't shown why I'd taken it out of another boat by failing then I'd be done. I'll wait for the parcel from Westborne to finish up.

Give 12V the 850 seems to turn the prop into a fan. If it shifts water as well as it shifts air I should be happy.

Oh, and if anyone wants a Rescue Launch - http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=260246479059&ssPageName=STRK:MESE:IT&ih=016

Thanks

Phil

grasshopper · « **Reply #69 on:** June 04, 2008, 12:21:49 AM »

The link to Ebay shows the Range Safety Launch from the MAP plans service in 1/12th scale - it's not an Aerokits model. I'm pretty sure it's the same as the model that Deans are doing in 1/24th scale.

Am I sad or what? still got the plans from when my brother made it late 60s ? paid 12/6 (shillings, came after groats) then passed them on to me - still on my list to make.

Shipmate60 · « **Reply #70 on:** June 04, 2008, 01:13:34 AM »

Phil,
This is half the fun getting her running as you want to.
Too simple to just bung a 700 BB Turbo in.

Bob

Philipsparker · « **Reply #71 on:** June 04, 2008, 08:01:04 PM »

Well, the boat has been up on the plane ! 850 motor, big prop and the biggest Electronize speed control did the job.

The only problem was I had smoke coming off the motor afer 10 minutes ! I suspect the prop is too big as replacement with the original 2 blade version seemed to make things better. Anyone want to explain why a 2 blade give me as much speed as a 4 blade ?

More on my blog: philsworkbench.blogspot.com/2008/06/fairey-planes.html - and you might enjoy the Bouncing Betty stuff as well (don't worry, it's safe for work)

Phil

Shipmate60 · « **Reply #72 on:** June 04, 2008, 08:46:37 PM »

Phil,
The larger prop on the 850 motor supplies such a load that it slows the motor down.
This loading increases the power consumption, as the amps rise it generates heat.
When the heat generated exceeds the heat available to be dissipated from the motor the temperature rises in the motor.

Bob

Philipsparker · « **Reply #73 on:** June 04, 2008, 10:45:00 PM »

Right - so a smaller prop means more revs which generates the same thrust as a bigger prop running slowly. BUT the smaller prop means less current draw which should mean a cooler motor AND longer battery life.

Presumably there is an optimum prop size which I'll have to work out through experimentation. My gut instinct is that a slightly bigger two blade prop would be better. The one under the boat at present looks too small but I don't want to go too big - 50mm perhaps.

Phil

Alastair_I · « **Reply #74 on:** June 05, 2008, 10:05:29 AM »

I acquired a secondhand Hunstman 31 with the 46" glassfibre hull a few weeks ago.

For the first time in my ownership it got it's hull wet yesterday and had a good run around the lake. As supplied it had a Torpedo 850 with an X55 2-bladed prop powered by a 12V 7A lead acid battery. The speed controller is a Sonik M3 (?? programmable I found the instructions on this forum posted quite recently).

Due to some TX problems I don't had the ESC set-up quite right.. but on full throttle it rose onto the plane quite nicely, and cruised on 3/4 throttle looking very smart. The battery lost oomph quite quickly, but I was able to cruise for 20-30 mins before I had any concerns about retrieval. I put that at part down to it being a possibly elderly battery with limited use in recent months (heavy dust on the boat when I acquired it).

Al

PS, has anyone ever commissioned brass or nickel-silver etched window frames for the Hunstman?

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Author Topic: Fairey Huntsman Power (Read 36784 times)

Stavros

Philipsparker

Philipsparker

Philipsparker

Stavros

Philipsparker

Philipsparker

Bradley

Philipsparker

Philipsparker

Philipsparker

Alastair_I