Model Boat Mayhem - Forum

Dry Dock / Shipyard: Builds & Questions => Sports Boats R&D: => Topic started by: aeronut on September 16, 2019, 10:22:07 AM

Title: Club 500 racer handling
Post by: aeronut on September 16, 2019, 10:22:07 AM
Does anyone have experience of modding the Club 500 boats to handle better?  Not using mine for racing, so not standard, but sometimes it will just not quite get up on the plane properly, then tip over at around 45 degrees and run along like that.  Current thinking is that it's down to the chine being not sharp enough because of the vac forming, but I'm not too sure what I can do to correct that - hoping someone here has some experience to share!


Gordon
Title: Re: Club 500 racer handling
Post by: chas on September 16, 2019, 11:03:33 AM
I've never had a club 500, but I did plenty of pairs racing years ago. As your boat is modified the first thing I would check is that the model has it's weight set low in the hull and the second is that the prop isn't too large giving a torque roll to the hull and preventing the revs picking up quickly.
Chas.


Title: Re: Club 500 racer handling
Post by: DaveM on September 16, 2019, 12:49:56 PM
What you're experiencing is called 'chine walking'. If you Google that phrase then there are plenty of descriptions and possible solutions, certainly for full-size boats. The Fairey Swordsman is prone to this, largely because it's a little too broad in the beam for its length. The solutions suggested are to decrease the power, trim the stern with wedges and/or add some weight in the bow.

DaveM
Title: Re: Club 500 racer handling
Post by: Martin [Admin] on September 16, 2019, 01:12:32 PM
 
You could also think about fitting some form or 'running strakes' along the bottom, to help keep it straight...

Or 'dagger plates' like a hydroplane.

https://www.google.com/search?q=running+strakes&safe=strict&client=firefox-b-d&channel=crow&sxsrf=ACYBGNQj97JFaMaURgwdAl4q893fX1_Qbw:1568635869507&tbm=isch&source=iu&ictx=1&fir=evfcBa-JJYUt_M%253A%252C9TwVkDO_TY-fnM%252C_&vet=1&usg=AI4_-kTIe7_SLa1l3JMWwKQi_AKzeQFyxg&sa=X&ved=2ahUKEwipuqL-p9XkAhX6URUIHRqpDUIQ9QEwA3oECAMQBg#imgrc=evfcBa-JJYUt_M:
Title: Re: Club 500 racer handling
Post by: Netleyned on September 16, 2019, 01:24:51 PM
The 500 was designed as a stock club racer.
540 motor on 7.2v to keep everyone equal.
No probs with it's handling as designed.
Upping the power or prop will give the effect
you are experiencing. As designed a good fun boat
and some great club racing.
If you want more speed, buy a faster Hull.
Ned
Title: Re: Club 500 racer handling
Post by: aeronut on September 16, 2019, 02:57:50 PM
Thanks for the suggestions chaps!


Chas - the weight is all as low as I can get it and it'll do this trick on either side, so fairly sure it's not torque related.


DaveM - I'll certainly not be decreasing the power - I already have it toned down a lot!  I'm currently fitting some trim tabs on the transom to see if they help.  Interesting about weight in the bow, as someone else has suggested it was too heavy at the bow!  Next time out, I'll move some lead around to see if that helps.


Martin - Yes, I could fit some running strakes if I have to, I'm keeping that option open for now.  I have some turn fins for it which I can fit, though not yet 100% certain of correct positioning for them.


Netleyned - what you say is mostly true about it being what it is, though a fellow club member has a stock one which also has some odd quirks.  Faster hulls being investigated.


Here's a bit of video showing what it does - as you'll see, it runs well like many similar boats, but watch what happens in the last two seconds!
https://vimeo.com/359114281 (https://vimeo.com/359114281)
Title: Re: Club 500 racer handling
Post by: Taranis on September 16, 2019, 08:06:43 PM
Looks like the battery moved.
Its not going any faster than a stock 500
Our boats fly and don't experience what you have
(https://photos.smugmug.com/Kirklees-MBC/i-7RLNbrg/0/63513787/X4/DSC_0141-X4.jpg)
Title: Re: Club 500 racer handling
Post by: Taranis on September 16, 2019, 08:31:31 PM


<iframe>frameborder="0" scrolling="no" width="720" height="1280" src="https://api.smugmug.com/services/embed/8731290670_3MsSxx8?width=720&height=1280&albumId=73392404&albumKey=6xcCrH (https://api.smugmug.com/services/embed/8731290670_3MsSxx8?width=720&height=1280&albumId=73392404&albumKey=6xcCrH)"></iframe>
Title: Re: Club 500 racer handling
Post by: Martin [Admin] on September 16, 2019, 09:50:25 PM
 
.... only seems to work for Utube Andy.  {:-{
Title: Re: Club 500 racer handling
Post by: Taranis on September 16, 2019, 09:55:05 PM
OK thank you I'll try remember  :-))
Title: Re: Club 500 racer handling
Post by: Netleyned on September 17, 2019, 07:51:44 AM
Smugmug vid working in Grimsby OK Andy :-))
Ned
Title: Re: Club 500 racer handling
Post by: aeronut on September 17, 2019, 09:03:56 AM
Taranis - Thanks for your reply.  You're right that my boat is no faster than those in your video (which works OK here), so I can only think that my boat's oddities are down to either weight or CG.  Mine has a watercooled brushless motor and ESC, running on a 2S Lipo battery, so whilst battery weight is certainly lower than standard, motor/ESC weight is probably more.  This leads me to think that my boat's CG is probably further forward than a standard boat.  Anyway, as previously stated, next running session will see the CG moved by the addition of lead, to see if that makes a difference.


For the benefit of others, I do have a faster hull of similar construction on order, but it'll be a while before that arrives and is built.  When that happens, I may well restore the Club 500 boat to standard and try some informal racing with fellow club members.
Title: Re: Club 500 racer handling
Post by: ChrisF on October 07, 2019, 09:28:08 PM
I recently bought one off a fellow club member, it's pretty much standard (7.2v NiMh and brushed motor) and it handles a treat. I can't use full throttle though, as even on calm water, it starts to hop, just like those racing in the video, so I think it will be very difficult if not impossible to get much more usable speed out of it.

Funnily enough one of the other members was experiencing handling difficulties with his boat. It turned one way fine but when going the other way was very twitchy and would sometimes dig in and even spin. I'll ask him if he's sorted it and whether the motor etc. is standard.

Chris
Title: Re: Club 500 racer handling
Post by: aeronut on October 08, 2019, 08:45:22 AM
Chris - good to hear of the experiences of others.


Yes, there's a limit above which porpoising will occur but, in a non-racing boat, trim tabs should help with that.  What they shouldn't be doing is getting twitchy and digging in, so I'll be interested to hear your clubmate's thoughts and experiences.
Title: Re: Club 500 racer handling
Post by: red181 on October 16, 2019, 10:05:44 PM

I raced for a number of seasons a club 500, and we raced to the original idea, stock. As mentioned, these are not fast hulls. This might sound off track, but some of the issues you are facing is due to the rudder blade that's comes as stock being too wide, that's what your pal is suffering with, one way is better than the other due to torque roll. If you experiment, keep the length the same, but slowly make the blade narrower, this will improve turning.


They do porpoise, and moving the battery tray slight movements forward, from the most rear position will help. I recall, on choppy days I moved it forward up to an inch, on calm days had it back. People running heavy boats didn't suffer this, as they sat lower in the water, and obv went slower!


My boat was dead light, no excess weight, and won the season champs a few years running, however, it did suffer with porpoising at speed, which you can cure as above.


If you look at this video (crappy quality!) the boats are hopping around, my boat is later in the video, the gulf blue and orange colours, number 40, it was the fastest boat, and you can see its hardly porpoising, just due to battery placement moving the cog



https://www.youtube.com/watch?v=dXYyD3xjGn4&feature=youtu.be (https://www.youtube.com/watch?v=dXYyD3xjGn4&feature=youtu.be)


I had forgotten how slow they where! stock Johnson 500 motor, and nimhs batts!
Title: Re: Club 500 racer handling
Post by: ChrisF on October 16, 2019, 10:38:37 PM

Thanks Red, that's interesting. I have wondered whether altering the CG would help reduce porpoising.


I can't move the battery easily in mine though as I had to rebuild the supporting structure for the rudder servo, ESC and Rx not long after I bought it, which I did in ply and fixed it securely to the battery box. I don't know what the motor is but I reckon it goes faster (well it looks like it does!) than the stock racers, as I said I can't use full throttle. Obviously if the motor is more powerful it won't meet the rules (and maybe the replacement servo mounting etc. would fall foul of them as well) but I bought it to get used to piloting a powered boat and at higher speeds and to take part in the informal club racing for which it has been great and not having to worry about damage too much.


I'll mention about the rudder when I'm down the club again.


Chris