schottel drive help?

[Reckless]

hey I'm thinking about coverting my springer .. and my bashed Bankert to Schottel drives... single on the springer and twins on the bankert (one on the bow and one in the stern)

now the bankert will be a bit of a strange build up as I'll have to do fairly extensive mods to the bow of the hull .. and I don't plan on normally running both except for 'working' aka full power pulls.. side pushes .. extreme course manouvering .. but anyways

anything specific to mounting setting up these drives I need to know about before I order and start hacking my hulls? :D

[toesup]

anything specific to mounting setting up these drives I need to know about before I order and start hacking my hulls? :D

I have 2 of the Graupner Schottle drives in WW (Springer)
http://www.rcgroups.com/forums/attachment.php?attachmentid=1696030

You need to make sure the input drive mounts are WELL supported as they are a known weak point on these drives.
You WILL need a high torque servo to operate the Schottle.
As they come, the drives are very rough in their finishing (plastic flashings etc) so spend a few hours cleaning up the nozzle and prop to increase the performance

[toesup]

... also...

Go for the Graupner 700 or 900 motors...

[bigford]

reckless

your going to have to beef up the floor of the banckert as the plastic is
real flimsey. unless you have the wooded hull version.

[Reckless]

toes -

the schottels I am looking at are only rated up to the 600? (little schottels.. not the bigger Z drives) ... but thank you ;) I'm thinking 600's on 12V for the bankert.. and 600 on 6V for the springer

bigford -

I was kinda counting on that... mine is the plastic hull but it is partially fiberglassed at the moment as it was lengthened about 2.5-3inchs near the stern by the previous owner. the previous glass work inside is chipping off around the edges now .. and it was mixed too hot.. as there are heat dimples/imperfections around where the glass/resin were laided.. so I'm thinking a clean out asmuch as possible and then redo it but this time the whole inside of the hull... and well I'll have to hack up part of the bow anways to make a 'slot' for the schottel to sit in

[Umi_Ryuzuki]

For the small graupner drives, I was told to use the 400 series motors with the
2.33:1 gear drive. And, run the whole shaboo on 12volts...

Has worked fine in my SDM tug.

Can't imagine it could go wrong if Ron Burchett recommends the set up. :)

[Reckless]

umi...

are you talking of the speed 400? or equiv?... I'm NOT going to say someone is wrong (especially with all the more experienced people here) ... but the stats for the speed 400 say it's only good to 8.4 volts ... maybe with the 2.33:1 and the Schottels already built in gear ratio (anyone know what it is?) 12V doesn't burn up the graup 400?

I do have a pretty good grasp of electronics so I can understand how it would survive... but given I've gotta order everything ... I really dun wanna break/burn something up :( :O

[Umi_Ryuzuki]

This is what I have been running for the last two years...

GR170323 Graupner 2.33:1 Gear Drive with 7.2V SPEED 400 (http://www.hobby-lobby.com/gear400.htm)

The drives are already geared 3:1 ratio.

The only thing changed from the image below, is that I am using
two Mtroniks ESC, rather than the blue Proboat... Much better control.

[Reckless]

yeah your drives look a little different then the ones I am looking at .. but I get the jist

I'm looking at the GR1761 drives from harbor models

as much as I would love to have my tugs redone with the schottel's by the big regatta I am planning to attend in Aug it just won't be done.. I have a choice buy all the drives and such or buy the RX's I need to convert all my boats over to the 2.4 I just received :D

I'll prolly see Ron in person in Aug so I'll see if I can still a little of his time then about powering it

but another question about mounting .. how does one mount these wonderous little drives is there a mount that gets perm mounted in the boat and then they bolt down at their "flange"?

also... is the flange/shaft really sealed .. or are they ment to be mounted above the water line?

[offshore1987]

In a true heart to heart dont use the schottels they are truly shite :D

never again will i be puttin such crap into any of my models

But this is my opinion :)

good luck with it though :D

[Reckless]

can you say specifically what's 'shite' about them? .. machining... build.. materials.. forming?... I've heard it mentioned that they need to smoothed of flashing and such from them....

I'll have to make some measurements to see if the bigger Z drives would work too (which is what I would perfer ;) atleast on the bankert) I beleive it's the Z drives that Umi has lookin at his picture

[toesup]

can you say specifically what's 'shite' about them? .. machining... build.. materials.. forming?... I've heard it mentioned that they need to smoothed of flashing and such from them....

I'll have to make some measurements to see if the bigger Z drives would work too (which is what I would perfer ;) atleast on the bankert) I beleive it's the Z drives that Umi has lookin at his picture

Yes...
All of those things are wrong with the Graupner drives... at least the bigger version. (2335's)

The ones Umi is using (shown in the picture) are the smaller Graupner 1761 drives, but with a different method of 'steering' them than Graupner shows in their advertising.

[offshore1987]

imo everything you just said is wronge with them, for the price they are/where its shockin, they say to use these with the 900bb motors yet the 900bb motors can destroy them :confused: so well done graupner lol

So far everytime i have used my tito at the lake the schottles have gone wronge some how, the only thing they havnt done is leak

the plastic thing around the prop is naff and weak too, nothing lines up as it should, my left one is totally out and the cap dosnt even fit on it, il post some pics later

but yeah never again, sharfts all the way from now on

i say it as i see it :) all the best

[Umi_Ryuzuki]

Iteresting, The drives in the Tito Neri had a bit of water come up the steering shafts, but
there were not any issues as Offshore describes.
Others have recommended reinforcing the bearing support at the drive input shaft.
Up till now that was the only issue I have consistently heard.
As for steering throw, Billy's Tito was given 180 degree throw(90 degree ES) using
the standard steering set up, and adjusting the servo throw via the transmitter.

The smaller drives that I am using developed a crack due to a high speed dry run caused by the Proboat ESC prior to putting it in the water. I repaired them, but, Subsequently, the rear drive casing failed and cracked open when I sucked a tow
line into the rear drive and stalled the propeller. The vertical drive shaft threw the
propeller shaft to the side, and thoroughly cracked the housing. It has been replaced.
I may use the housing as a bow thuster in a future build.

The steering on my small drives was giving a higher gear ratio. I have a 3:1 drive gear
on the servo, so I get 270 degrees of throw. It has been adequate up till I did that
crab walk with the barge. Now I feel like It needs the full 360 degree throw so that I
can crab walk the barge the opposite direction. Reverse is not as powerful with these drives.

:)

[Reckless]

yeah I only want 180 deg of throw

how about mounting? does the main mount need to be above waterline? or it is okay lower?

[Huntsman]

:) It is my opinion that too great an expectation is put on these units; apart from an initial glitch in the installation of the schottles, my fault, ( see the Tito comes to life thread) I have had no problems with them.

They are not intended to drive a tug along like a fast electric yet folk try.
Giving full opposite rudder at full speed ahead is not a normal procedure yet it is done.

I have not seen any pictorial evidence of the bearing support failing yet it is a "fault" that is rolled out time and time again.

I have seen build pics with the drive line 1/2" out of true, cheapo servos fitted against advice then these same folk blame the gear.

If fitted correctly they do what "it says on the tin"

If you stick them on any old hull then you will not get the real deal.

[Reckless]

heh... I've had a really stupid moment... all this time I've been thinking "yeah I'll talk to Ron next time I'm in Burnaby about this (aka the Aug Regatta) .. but I was somehow mentally confused with Gary *oops*

heh I see Ron quite regularly.. infact I was working on his Daughters Car today ;)

I talked to him briefly about some up comming events and about the schottels .. he said one I had the drives he would help me with placement and what's needed to convert my hulls.. the springer should be pretty straight forward.. the modifications and coversion of the stretched bankert hull should be the interesting one!