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View Full Version : A few newbie questions re Miss Geico v2



doogledee
07-31-2013, 11:49 AM
Hey all,
have been lurking on the forums for a while waiting for my account to be activated, but now all is well :)
I have zero experience with RC boating and recently fell for the temptation and got myself a MG.

Having spent some time on the forums reading I also picked up from my LHS the rudder bracket and rudder parts for the Impulse 31, because when I looked at the two boats side by side it looked as though I could use the Impulse rudder parts to offset the rudder on the MG, which I understand is a good idea for keeping up the speed in turns.
It was mostly a bolt on fit except for the two holes in the original bracket that needed opening out to 4 mm to fit the screws from the impulse that where the only ones I had to hand for fitting. One of the screw holes had to be enlarged slightly for everything to bolt up nicely. Pictures are attached of the result.
Here come the questions :)

1. Does this rudder config look ok?

2. I currently only have a pair of hard case 2s 4000 Mah batteries (35c), since these can deliver 140 amps I am assuming the should be fine for the boat, at least to start with? Is it normal to use hard or soft case pack for boats? I assumed hard case would be better as the casing is more robust in the event of a crash so this is what I got.

3. I am also aware that the stock plastic prop is not great and got an alloy prop with the same dimensions as the orig plastic one (1.6 x 2.5) 40.6 mm diameter. On the bag for the prop is a lot of information that I don't understand:
30%PH___50%PH___70%PH____90%PH
30.55_____47.34____62.58_____77.02

average PH___propeller hub___dog drive
54.38_________8.00_________3 mm

What does all this mean? could someone explain this to me a bit more?

4. is there a good guide to sharpening and balancing a boat prop online that someone can give me a link to?

5. I see a lot of different recommendations for props, but the number don't mean anything to me. is there a convention for how the numbers relate to the props diameter and pitch? If so would someone mind explaining it to me?

Here are the photos of the rudder mod:
103145103146

Sorry about the crappy quality, but only had my phone handy....

Look forward to hearing from you all, and hope my questions are not too dumb....


Leif

doogledee
07-31-2013, 02:33 PM
Had a quick trip out to the local lake today while waiting for replies :) Runing 4s and stock plastic prop, to test the rudder mod and get a baseline for the boat. Great fun :) batteries were placed with their back edge level with the cross brace in the plywood frame behind the motor mount (towards the back of the boat).
this seemed to work very well, but I would guess the boat is a little rear heavy.
Anyone have any suggestions as to where the cog should be?
The boat bounced a little at top speed (used the prog card to make the throttle curve linear), but other than that all was great.
Next up will be a few more runs with the stock set-up before I start modding the hull to make it level etc.
So far I am happy with the speed but I can deffinatly get used to this, and will want to go faster in the future :)

Leif

doogledee
08-01-2013, 11:55 AM
still waiting for some input from the forums, but I have found a lot of info on props from searching the forums. Feel much more informed, but still confused :) However I have ordered a few different Graupner props from my local dealer and a couple of CNC props from this site, so looking forward to getting them so I can start some testing...

SloHD
08-01-2013, 12:27 PM
Some good props would be octura x642, m445, Prather s220. Look at the specs for those props. That'll tell you the general vicinity you want to stay in with pitch, diameter, ect...

Im sure you can tell by now the impulse hardware wasn't made to match up with the geico hardware. It does look good but the old geico rudder mount sticking out like that would drive me nuts. Also I would try to reconfigure that linkage rod at the rudder. That dramatic bend can not be good...

I suggest searching the forum a little more. Kintecracing.com makes a geico offset mount that would of been better. Also have a look at the last post in the following link. Should help you with some ideas to clean up the hardware back there.

http://forums.offshoreelectrics.com/showthread.php?41469-Just-bought-a-MG-29

SloHD
08-01-2013, 01:50 PM
Obviously this is not on a geico but this is geico 29 hardware with a kintec offset rudder. Notice with a bigger prop, you might want to round off the bottom corner of the strut mount. Might want to do it anyway to get it out of the prop wash a little more.
http://i678.photobucket.com/albums/vv147/thewilsons888/0E8CFBC0-D641-4ACD-BD53-CB848E9391CA-1521-00000379DBB6F7FA.jpg
On another note, why delete your post iop65?

doogledee
08-01-2013, 04:13 PM
Hi,
thanks for the tips :) mc appreciated. The original bracket was put back in to act as a spacer, I did not cut it at the time I took the photos, just in case I had made a mess and the offset rudder solution didn't work well for me.
Now that I am happy with the offset rudder I have marked and cut the original bracket so there is nothing sticking out back there any more, a bit like the last photo you posted.
My main reason for using the Impulse parts was that they are readily available for me from my LHS, as I live in Norway mail order sites in the US are 10-12 business days away :) Also these parts should hopefully be available from most LHS that stock ProBoat, so for others in my situation, this might be a viable option, at least that was my thought :)
A more specialised mount would have been better, with less metalwork involved, but it was a matter of convenience for me as I have a junior hacksaw and a drill.
I will be rounding off the strut as suggested , great point that I missed when doing my mod, thanks.

On the prop side I have ordered:
OSE CNC prop 42 and 43 mm
Graupner 40, 42 and 48 mm props (these from my local Graupner dealer).

So I should have some room for experimenting.
The Prather s220 prop is 43 and a bit mm in diameter and has a pitch of 2.6" this seems to be a lot more than the stock prop. Will the stock ESC and motor be ok with this? I know I have already ordered a few bigger props than this but I kinda went a bit overboard when I decided to place my order... these things happen :)

Thanks again for the reply. Look forward to getting back out on the lake, going to replace the bullets between esc and motor with Kontronik 6mm version tomorrow, and I will be swapping to EC5 connectors on the battery side as well as I thought the plugs got a bit to warm with the stock configuration.


Leif

doogledee
08-01-2013, 04:21 PM
I will be cleaning up the pushrod configuration as well in the near future, just need to make time.

SloHD
08-01-2013, 05:03 PM
I kinda figured you were just using what your lhs has. Just figured I give you more ideas on how most offset the rudder. If you like it and it works, that's all that matters. :)... To be honest I kinda like the looks and the configuration of the impulse hardware over the geico hardware.

An s220 prop would be fine with the stock electronics. Just try not to go too much bigger than that. As far as the hard/soft case packs: it really doesn't matter. If youre looking at 2s hardcase packs, just try and get direct wired.

doogledee
08-01-2013, 06:21 PM
I am happy with the looks now :) getting rid of the overhanging remains of the old strut cleaned things up a lot.
It should be nice and easy to add a second bracket and rudder if I want to make a dual rudder set-up later.

On the batteries I have been looking at some racing packs for cars with no wires, just 4mm jacks on the ends. Theese might make a nice set up for keeping the battery wiring simple and easily getting rid of the series harness on the esc.

Hopefully the props wont take to long to arrive, in the mean time i can get started on smoothing out and cleaning up the underside of the boat :)

Leif

SloHD
08-02-2013, 02:16 PM
Yea that's what I was saying. Try and stay away from the "roar" 2s bullet packs. Of coarse they'll work, but it creates more bullets/connection's, which in return adds resistance. You want to cut down the resistance with the least amount of connections. I use a set in my mystic only because that's what I had before I got into FE boats. But since then I've purchased direct wired packs only.

doogledee
08-02-2013, 02:43 PM
Ok get you :) i picked up a pair of hard ase bullet packs today, but i can use them in my racing buggy :) will look for some direct wired packs this next week.

hydro_pyro
08-03-2013, 08:29 PM
If you switch out the stock connectors for bullets, there won't be any extra connectors. Just bend the wire next to the bullet end before you solder it, so they have good clearance.

I use hard packs in my BJ29... Works great this way.

doogledee
08-15-2013, 04:04 PM
I have been looking for some extra batteries and have found som 7500 MaH, 2s Hard Case (75c) packs that are direct wired and the right price. Will pick some up tomorrow and get them soldered up with the right connectors etc.
Looking forward to it, as I will have an extra set of batteries so I can get two runs in :) Will let you all know how I get on.
Loving this boat now that I have it dialed in and the bounce is gone :)