MHZ Mystic 114 - my first proper build

[TiTu]

Hi everyone,

after a lengthy debate mostly with myself and by guiding from Manuel I made a choice between HPR C5009 and MHZ Mystic C5000 114 and picked up the later from MHZ christmas sale. The biggest reason behind was having a hull that can handle well in turns and that there was a topnotch thread covering the build process (thanks to Kent for that). I hope that Kent won't mind as this build will be quite similar as his was because it was the inspiration to build one of these cats. My goal is to have a cat that will have reasonable speed, good handling and as long runtime as possible. I've planned to start with octura x442l/r and 6s lipos as those are what I got and take it further from that.

The hardware I currently have:
Mystic 114 hull
2x 4082 1600kv leos (had one of these previously)
2x Seaking 180A escs (same as above)
drives from MHZ
carbon parts also from MHZ
custom made rudder from Manuel Wenny
hydraulic rudder steering from MBP-rc
+other bits and pieces

The build process won't be fast as I'm having quite a long to-do list and want to spend time with my wife and 5 months old son, but most importantly, waters are still frozen for 3 to 4 months here in Finland.

First problem came up today when I got the drives from backorder. The shafts were different lengths and one of them was a bit larger diameter at the flex end and was binding and not rotating freely. I hope this will clear out well with MHZ.

I was lucky to get the custom made rudder for the hull from Manuel (thanks again Manuel!) as that gave me the chance to use working hydraulic rudder steering rather than to just use a mockup besides push-pull system.

Wish me luck, chime in comments and suggestions as here I go!

[Chrisg81983]

You will be very pleased with the outcome as long as its built correctly. You cant go wrong asking kent and manuel for help either. Both of kents mhz's were top notch builds , and manuel is very very knowledgeable as we all know. There are also many other people who know a great deal about what it takes to build a great running cat. Good luck with her and if there is anything I can help with please ask. All I can say is take your time, read as much as possible, and ask questions. I have a hpr06 build that may help a little here on ose.

[Pwb201]

Goodluck!!
Have one of my own and my brother n law has kents 114 that you spoke of.they are both awesome cats and I run 2200kv leos and she rips!

[nata2run]

Hello, I feel all special now its an awesome hull!!! I have all templates for mounting drives if you need them?? this is definetly the right hull if you like a nice look. don't be afraid to ask as many questions as you need. the only thing I would change is the 1600kv motors to 2200kv on 5s or 6s. Today I got 80mph in my "OLD" HPR with that same setup. If thats enough then cool!!?? but you cant expect to go a lot faster, maybe with 450\3 props, I was running 448's and everything cold as!

@ Phil, Hows everything going???....long time no hear. How's "My Boat going" ?? I always wonder...

[iridebikes247]

Agreed with nata2run. It is cool to stay conservative when setting these boats up but come on man you've got an MHZ mystic 114 lol. I would go with the 2200kv leopards or maybe step down to the 2000kv if you're running 6s. The esc can take the 2200 but its pushing it. I have run the seaking 180/5s/1600kv leopard 4082/x447 in a 42" MHZ boat and it runs all day, its fool proof. Have some fun and try out the 2000kv motors, if you have the itch go for the 2200kv you won't regret it.

[Pwb201]

Yup 2200 is the ticket but if you've got the 1600 and wanna stay In a budget with motors that's fun too. You can always swap out if not fun enough.

@ Nata
Robs boat is great he ran it a few days ago. I still haven't seen it run. He's scared of her lol.
Wants me to drive says the steering is very touchy I'm thinking dial down the % on servo but ill have to try it first may just be him.

Mine hasn't seen water since it left the water at 87 mph on 5cell with 445 3 blades, took to air off a cross wind and I needed a pilots license for 2-3 seconds. The batteries broke loose and did some damage Inside but alls fixed and reinforced.

@titu if I can stress one item it's secure the trays more than you think, 6cells are bricks and will damage interior if loosened. Look into rail system.

[nata2run]

Phil, I manufacture lipo rails for that hull if interested...???

[Pwb201]

O no thanx maybe if they let go again I'll take a set

[kingwrench]

I will be following this build, looking good. Def do not skimp on keeping the batts in place!

[TiTu]

Hi again,

thanks to everyone for the tips, suggestions and advice. Regarding the motors, most of the builds I've seen have 2200kv leos (if using leos at all), but as I got already one 1600kv, thought to start with those. Hadn't planned yet how the batteries will be mounted, but I'll take heed of the advice when the build comes to that.

@Kent: and I thought I'd be happy to get 60mph with long runtimes based on my previous boat , so if the 80mph is achievable with the hardware, that suits me perfect for now . Thanks also for offering the templates for the drives, but it seems that I have to do my own template as MHZ have changed the drives a bit from the image on their webpage. As for now, it's fastened only with two bolts to the transom instead of three and it's shape is a bit different too.

Managed to make some progress with the project during the holidays. Nothing much though, but got the rudder mounted along with the steering equipment. The rudder's build quality was excellent and it was a direct fit to the hull. Mounted three brass tubes through the hull and epoxied them with some fiberclass to the hull, should be sturdy enough for my needs. Only thing I modified in the rudder was a little cap to cover the top end of the rudder's shaft. The hydraulic steering was easier to install than I thought and seems like it will work like a charm. I'd think I'll got around 30-35 degrees of turn to each side. Time will tell if that's enough.

[Chrisg81983]

Looking good man !!!! I think you should have more than enough travel for the rudder movement. I use less than that on my hpr 06 I am assuming it should might be the same for your MHZ, but kent or manuel would answer this better than me. Keep up the nice work

[TiTu]

Quick question before I drill the holes for drives: should I reinforce the transoms with some cf-plate? I'd rather do that before (if necessary) any drilling. Tried to loof for it, but I think Kent didn't do that on his build though I might be wrong.

[nata2run]

Do it before if you want to install it. You don't want to risk gluing in on an angle, so best is to mount then then glue in all together with some thickened epoxy, and grease on the drive/screws so it don't stick to that part.

[Chrisg81983]

Yup grease or vaseline works great to keep epoxy off of things you don't want to get glued in.

[silver]

Titu, nice built I bought a Christmas pack from MHZ in 2011 and did today my first little run.
The boat is very cool and nice in the corners.
Still some trim work to do but it was a good run.
Good luck with your building

[ManuelW]

Will also follow the build. If I ever decide to make a few of these rudders again, can I use your pictures for advertisement. I don't know which camera you have but the photos look awesome!

regards,
Manuel

[TiTu]

Will also follow the build. If I ever decide to make a few of these rudders again, can I use your pictures for advertisement. I don't know which camera you have but the photos look awesome!

regards,
Manuel

Feel free to use them if you want, I don't mind that at all! Camera which I'm using is an older Canon EOS 450D/EOS Digital Rebel XSi.

Thanks for the tip of using grease/vaseline for the screws while gluing things together, saved me from one headache.

Made some progress again. Wasn't too happy with the motor mounts that came with the set as they were made from 2mm cf-plate so made another set of mounts. Made them with smaller shaft hole so I'm able to use thrust bearings without putting more stress to screws that hold motor in place. Making those motor mounts required a little more work than I thought as I don't have any cnc milling machine but they turned up pretty nicely imo.

Got also done the transom reinforcements and templates for drilling the transoms.

[nata2run]

That looks good, but very close to the bottom!! also make sure you can fit the water pick up tube between the tunnel and the drive. you may have to move it out a little. clear about 7mm from the sharp point of the sponson.

[nata2run]

Also, I have gone away from the idea of using thrust bearings....more stuff to go wrong!!!

[drwayne]

Also, I have gone away from the idea of using thrust bearings....more stuff to go wrong!!!

burn and learn

[nata2run]

burn and learn

oh yes, I forgot you been there done that.

[TiTu]

That looks good, but very close to the bottom!! also make sure you can fit the water pick up tube between the tunnel and the drive. you may have to move it out a little. clear about 7mm from the sharp point of the sponson.

And I thought it was better to get the drives lower than higher, and also close to the tunnel. But thanks again for pointing things out to me, I raise them up from the ride pad few mm as well as move them a little away from the tunnel towards the center of the transom.

And seems like I'll ditch also the idea of using thrust bearings if the experience hasn't been that good lol.

[nata2run]

No not a millimetre only half

[nata2run]

You can go close, just make sure the drive don't overhang the sponson, the drive could be a little more outward, so it allow you to drill a hole and install the water pickup.

[TiTu]

Yeah, I was hoping to get the drives at the same level as the bottom of the hull and avoiding any overhang.

[nata2run]

you need to be able to fit your pick-up roughly like this. Aslong as you have enough room you'll be fine
Transom Template_03.jpgTransom Template_02.jpg

[cyprus31]

Hi and good luck with your building proccess.
I also own a MHZ Mystic 114 and used to run it with Leos 4082 2200kv on 6s with x445 props. The boat with this setup was very unstable in water because I am under the impression that on 6s these motors could not hold stable turns and the hull was bamping on sides all the way. I then upgraded to x447 props. Besides it was a bit more stable with the new props, I could not trust it on high speeds.
I then decited to buy 2 new Leos of 1600kv but the same x447 props. Motors now more smoothly without any stability problems and I realy enjoy it also on full speed runs with max speeds of 132klm

I think the 1600kv motors are the best for this hull size.

[Chrisg81983]

Cyprus 31 I myself and many others had run the leo 2200 kv on 6s in single and twin setups. They run/ran very very well in my opinion. Was your cg and trim setup correctly for thoes speeds. That is a pretty fast setup and takes tone work to get running 100 %. I am currently running 2950kv n 2114 kv lehners in a twin hpr for very high rpms with no problems at all. She runs very stable, but took some work to get it that way. Whike it was very easy to get it to run rite with the same motors on a lower cell count spinning less rpms. I am prettu sure if you ran your 2200kv leos on 5s and not 6s you would of have the same outcome as when you went to the 1600kv.

[TiTu]

Hi all!

Had to take a break from the project due personal reasons, but I was at last able to sort a bit time for this.

Nice to hear from your experiences Cyprus, I'll definetly plan on trying those 1600kv motors as the speed is not an issue for me (mark my words )

I'll agree Chris, building and running a boat isn't the whole job, as tuning can require a lot of work too.

I made water pickups from 2 brass tubes, soldered them together and grinded the other ends to fit the hull. The holes in the hull are far from perfect, but I'm not too worried as glue will fill most of the holes and filler spray will take care of the rest during sanding.

Got the reinforcements for transom made as well from 2mm cf and the most dreaded part for me, drilling and installing the drives. Thanks Kent to point out that I'd need to install them a bit further away from the tunnel. The 7mm you suggested was just enough to have few mm's extra so there a bit more room to work inside the boat.
They came out pretty good, got them aligned so that the differences are about 1/4mm at most. However, as the drives and hull are, it was just impossible to get the drive angle to zero, as the drivesupport lifts the propend of the drive (as seen in pic). I bet that this will give me trouble when figuring out where the CoG should be. Afaik in normal situations it's supposed to be around 32-34% forward from the sponson transoms, but with this much of angle, I'll take it that it needs to be closer the transom than that 32-34%.

I'm thinking of where to put the water outlets and come up an idea that I'd put them to transom next to drives. Is there other con in this that I can't see if the water is actually flowing through motor and esc.

Another thing I'm thinking is should I use teflon liners with flexes or not. The teflon liners and aluminum tubes that came with the boat are a bit tight for my taste and the flex (3/16) will not rotate freely at all. I got a spare teflon liner with inner diameter of 6mm so I thinking to go with that if I end up using teflon liner at all. If I leave the teflon liner out of picture, what should the inner dia of the tube be?

[Chrisg81983]

Looks nice A few things though. Definitely run Teflon with this setup. Two put the water exits wherever the shortest amount of tubing is needed. It looks nice if you just take 4-5mm brass or aluminum tubing and just drill a hole n sidewall the exact size then epoxy in. Keep the tube flush with the outside of hull. When the boat is painted or vinyl applied the water outlet becomes invisible. I might put my next exits in the tunnel underneath hull, but this will make it hard to tell if cooling correctly. Third make sure the water pickups are free of burs where you soldered them together. Usually I try to make that inlet as straight as possible at the bottom while gently curving towards the top making it easier t put cooling line on. The less of a bend you have the more efficient the cooling system will be. Third I think the drives might have too much pitch to them. Are they set a high up as possible. I never had your hardware so I can't answer that question for you. She is otherwise looking great keep up the nice work.