perfect MG

[iop65]

finaly achieved the perfect running MG!

bought a used MG 29 v2 a few weeks ago for a really good price, i'm more into mono's but for that price i could not resist

the guy only ran it for a few times and put it on the shelf
tried it bone stock and understood immiadiately why it was sitting on the shelf -:)


blueprinted the sponsons ,raised the strut : bottom 2 mm above sponsons 0° angle: in chopy water boat ran great , the flatter the water the worst the bouncing was and the bow came up


blueprinted it again but now made the angle of the last sponson 90° ,was about 100-110°
lowered the strut :front 1.5 mm and back of strut 1 mm above sponson ( slight negative angle)

ran it today and this was what i was aming for , the bow only slightly above the water ,running full on the last to steps
water was not glas , slight chop ( like the lake is most of the time),so can not tell what it is doing in flat conditions but in looks just perfect ( boat is running almost flat) in conditions that i usely encounter

1500Kv stock motor
90A seaking esc
2 and 3s 4000mah (5s)
40 mm 1.4 p carbon graupner k-prop

it was a lot af work but it paid off !

[iop65]

some pictures

mg1.JPG

mg5.JPGmg2.JPGmg3.JPGmg4.JPG

[iop65]

as you can see i changed the inner layout because i hated the way the lipo's had to be attached with velcro


used 4-7 mm cooling tube to compensate for the longer distance to esc ( just in front of motor) ,has to shorten it still a bit but is a big improvement over the 3 mm tubes and cooles good

glued a 2 mm PS piece on the last sponson in a 90° angle and filled the gap (2.5MM!!!)

blueprinting looks rather messy ( the black /yellow/white/filler/PS) but is smooth as silk and corners are razorsharp

changed the stand , boat sits much more stable like this but i'm going to make something different this winter


first time out i hit a buoy ,boat was all over the place very hard to run it , and off course i hit something
that is why the tip off the sponsons are black

[iop65]

tested it on flat water this morning (the few times the lake is flat ) ; bouncing is still there but lower frequency and the bow doesn't come up as high as before but still not what i want
i want it to run flat in all conditions to have a save non-blow over hull to test out higher speeds ( now 64 km/h with the small 40 mm 1.4 p)



thinking of glueing 1.5- 2mm ride pats
this will give more ways to get a negative angle and adjust the hight prop-water , it is just impossible to bend the stuffing tube to the desired angle and hight(prop-water) now!

[BHChieftain]

You need to grind a space in the strut adjustment slot so you can adjust the negative angle correctly. See this thread. At the end is a video of the boat with the correct strut adjustment plus blueprint result (90degree edge). I am really happy with this result.

https://forums.offshoreelectrics.com/...t-modification

Chief

[iop65]

i did that Chief

the problem is the stuffing tube comes out off the hull in the wrong angle and it is impossible to bend it without damaging something (stopped trying that)
it needs to get higher and more angeld downwards and it can not be done like it is now , when i set it to the desired height i can only bend it to -1° angle

[BHChieftain]

You do need to bend the stuffing tube gently by hand. Someone else suggested using a drill bit to help hold the shape.
Chief

Sent from my XT890 using Tapatalk 2

[lenny]

I just leave the flex shaft in it when trying to bend and mod it to help with keeping it's shape.

[iop65]

i also leave the flex in to atchieve smooth bends , but in this case it's just not bending
even if it would bend it woud need a S-shape because it comes out of the hull to low ,needs to go up ( to get the correct dept of strut)and then bend it downwards again (to get a negative angle in the strut )

really don't like that!

but thanks for the suggestions guys

[iop65]

started this weekend
extra 2mm added

work in progress.JPG

[BHChieftain]

Hi,
Are you going to do the middle section of the sponsons or just the last section?
Chief

[iop65]

Hello Chief,

no i'm also doing the middle section and about half the first section ( so 2 X 3 sections total)
put them on this morning and the second coat of putty is curing ,need to get some abrasive paper,takes a lot of work to get i like i want

hope that al the work is going to pay off !

[BHChieftain]

This is a great idea-- I can't wait to see how it works!

Chief

Sent from my XT890 using Tapatalk 2

[iop65]

me to Chief!

i will let you guys know even if it was just a useless work without results

[iop65]

finished
finished.JPG

[BHChieftain]

Had a chance to run her yet?
Chief

[iop65]

No Chief , will run her this week
very hot the last few days/weeks, a lot of people swimming/playing/sailing/surfing in the lake where i "test-drive" just to dangerous
don't want troubles

[iop65]

sad to say things didn't get better ,bouncing was just the same
can not get the bouncing stopped on flat water , no fear off blow over but still bouncing
must say it was faster and riding on just a few cm hull and the prop !

changed the cog to the rear because i thought that more neg angle was the solution but it wasn't
will change the cog back to what it was at 24/07 and try again this weekend

perhaps the boat needs extra weight?
just using 2 and 3 s 4000mah and a 90a seaking
maybe some extra weight will keep it flat?

[SloHD]

Are you talking about center of gravity/balance when you say pog? Does 24/07 mean the cog is 7 inches from the transom?

[iop65]

no when i was testing on 24/07/2013 my lipo's were about 5 cm (2 inches) more to the front
going to do that again

the only way that the bouncing stopped yesterday was by moving the strut up so far (about 3-3.5mm above sponsons) that the speed was going down big time
then it runs flat but speed is gone

found out yesterday that to much neg angle made the boat "fishtailing ?" badly but doesn't stop the bouncing at all

[iop65]

ran her yesterday ,little chop
front lipo's at the back of motor
0° angle strut
strut 2,5 mm above sponsons

runs flat ,cuts through the corners like a knife ,seems it doen't mind the chop at all (no risk at blow over), seems it needs the chop to get flat

[ray schrauwen]

Squaring off the rear of the sponsons after blueprinting works well for me. Never bounces...

AQ 1800kv, AS/SF120 esc, Zippy 30C 2 x 4S 3000's, M445 for 4 min race and D/T 447 for 6 lap sprint. Strut is level with sponson bottoms and 0* flat. No wood inside with OSE CNC motor mount. Home made rudder offset + aftermarket FG cowling for weight.

[iop65]

tried something yesterday


glued (thin dubble sided tape) a 1mm plastic sheet on the end of the last step to create some lifting force

boat drives completely flat ,but speed came down a lot

did the same this morning ,but now 0.5mm plastic sheet and only 20 mm wide:still nose down but much more speed!


think i'm putting on trimtabs

i never had the need for trimtabs on my mono's ,other that adding bling-bling for the kids but i see no other way to keep this hull from bouncing on flat water

[kfxguy]

Did you ever get around to putting trim tabs on and if so what was the result?

[iop65]

yes i did
it helps but costs a lot of speed ,removed them
it just doesn't seem rigth : a cat with trimtabs