Looking for someone to finish set up of my MHZ Mystic 114

[pberzins76]

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[vvviivvv]

Update on my Mystic, MHZ got back to me the other day and they said the easy option eould be to trim my motor shafts down to allow room for my couplers and I should be fine. So I just have to wait until the couplers come.
In the mesn time, I went ahead and enlarged the holes on the motor mounts and mounted the motors. The port side wasn't too bad, as I just used a thin round ratail file, and didn't need to make too big of cut. The starboard side a differant story. Found out in addition to enlarging the hole, I had to notch the holes downward because the motor sat too high and would not line up with the driveline. I used my dremel, and took quite some time to get it where iI think it should be. I used SS flatwashers to back the bolts.

Easy option for them. Personally I'd be asking for them to rebuild the boat so the components work or get a motor with a shorter shaft.

Don't want to put a damper on your brand new boat as I know it's a sizeable investment in one of the better hulls on the market but I also don't want you to get mugged off by MHZ

[vvviivvv]

For example, I'm running lehner 2250's, you could get a smaller motor for sure as 2250's are power beasts for serious speed.. but the shaft is 1cm shorter than the 4035

see here

[vvviivvv]

Also find it strange a 5kw motor comes with 4mm plugs? I guess 8s equates to 160 amps to get 5kw but id still like some high quality 6mm...

[pberzins76]

Well one of my collets arrived during the week. The reverse thread coupler is on BO according to MarineFe. I took my motors to a machine shop around the corner from where I work on Friday, and had 1/2" of the shafts cut down, deburred and also ground in a flat for the collet grub screws. Took about an hour and he did a great job, and the guy didn't want any money when I offered to pay him! Don't find that too often!!!
Anyways, so I reinstalled the one motor with the collet attached. I slid the flex cable up, and it went straight into the coupling, so looks like I did alright with alignment. The tolerance is very close regarding spacing between the coupler and the stuffing tube bearing/flex saver, as the flex saver has about a 1/16" gap between the end of the coupler and the stuffing tube bearing. Just have enough room to loosen the collet enough to pull the flex cable. I turn the motor by hand and everything turns nice and freely from what I can feel. I know about leaving 4mm-5mm gap at the drive dog end to allow for flex shrinkage during high speed, but anyone think there are any concerns at the motor end because everything is up close? Pic below of the drivetrain.

[pberzins76]

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[pberzins76]

I still can grind a tad more off the motor shaft if it is necessary to increase the spacing between the coupling and stuffing tube. Or worst case scenario, I can just forgo using the flex savers and run without them...Just make sure my collets are thoroughly tight, which I do always anyways.....Or find something thinner for a flex saver?

[fweasel]

If it were my boat, I'd get rid of the the cable savers in favor of more room. I never use them anyway. I prefer more exposed flex cable in front of the collet so that I have room to wipe off grease before the cable slips into the collet. If I "had" to run the cable savers, I'd look into cutting the stuffing tubes back about 5mm, then remounting the bearing and oiler assembly.

[1coopgt]

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What's the Black piece next to the cable saver? Guessing your planning on using oil instead of grease on the flex cables?

[pberzins76]

Fweasel,I may just omit using the cable savers altogether to allow room for wiping off any grease before inserting the flex shaft into the couplers, as you suggested. I already had to do enough modifications (which I didn't expect I was going to have to do) to get the motors to fit, and I really don't want to do anymore cutting of things regarding cutting down stuffing tubes, etc.
1coopgt, the black piece is a stuffing tube bearing assembly with a built in oiler. I always just grease up my cables, so I'm not sure if I'll ever use the oiler. But its there as an option, I guess.
I still have to cut my flex cables to length, but I probably won't do that until the other coupler comes. I am looking at ESC's now, and open to any input/recommendations. Considering the ZTW ESCs. MHZ recommends 200-240 amp ESCs for these motors, and I been trying to figure if I should go with a 200 amp unit, which handles up to 8S. Or should I go with the 300 amp unit? Steven couldn't really tell me, as he hasn't had any experience with these motors. I asked RCBoatBitz, and they said the 200 amp would be more than enough for these motors. Any advice would be greatly appreciated! MHZ only lists the extremely pricy MGM Controllers, which look quite nice...But I would be looking at $800.00+ per unit, so that would most likely be overkill for my setup...But I could be wrong.

[1coopgt]

If you are going to use grease I would take the oiler and bearing off if they aren't needed. Which will also give you a little room between the end of the stuffing tube and the collet.

[rscheffer]

Rather big motors for a 115 mystic i have the 2x 4035-800 on 10 s in my 138 mystic ( also a nother 135 cm cat and in a 115 mono for that mather ) total running x457 props 5 min at 120 kmh .
https://youtu.be/qj3uZmAsyr8 ps 5514 103 kmh 6 min

[vvviivvv]

Fweasel,I may just omit using the cable savers altogether to allow room for wiping off any grease before inserting the flex shaft into the couplers, as you suggested. I already had to do enough modifications (which I didn't expect I was going to have to do) to get the motors to fit, and I really don't want to do anymore cutting of things regarding cutting down stuffing tubes, etc.
1coopgt, the black piece is a stuffing tube bearing assembly with a built in oiler. I always just grease up my cables, so I'm not sure if I'll ever use the oiler. But its there as an option, I guess.
I still have to cut my flex cables to length, but I probably won't do that until the other coupler comes. I am looking at ESC's now, and open to any input/recommendations. Considering the ZTW ESCs. MHZ recommends 200-240 amp ESCs for these motors, and I been trying to figure if I should go with a 200 amp unit, which handles up to 8S. Or should I go with the 300 amp unit? Steven couldn't really tell me, as he hasn't had any experience with these motors. I asked RCBoatBitz, and they said the 200 amp would be more than enough for these motors. Any advice would be greatly appreciated! MHZ only lists the extremely pricy MGM Controllers, which look quite nice...But I would be looking at $800.00+ per unit, so that would most likely be overkill for my setup...But I could be wrong.

nobody will tell you what esc to use too many factors and easy to get something wrong. you could get a set of the smaller MGM's but again probably not necessary

[pberzins76]

Just a brief update. Per the recommendations from RCBoatBitz and MHZ, I went ahead and placed an order for the ZTW 200 amp ESCs, as they are rated for using the max cell count recommended for these motors per MHZ's site. Having Steven's crew install the gold plated bullet connectors and will ship them once finished. Also ordered the programming box for the ESC's. Still waiting on the backordered reverse thread coupler from MarineFe to arrive before I do any more work on the boat itself. I can then cut the flex cables to the correct length, and hopefully I should be all squared away regarding the drivetrain/powerplants. Rest of the build, I imagine, should be pretty straight forward...Install the ESC's, steering servo, receiver, plum the cooling lines, and tidy up wiring.

[fweasel]

No need for a reverse thread collet. If they're properly tightened down, it won't matter what direction they're spinning.