Help me build a Sniper 45"

[kevinpratt823]

First of all, thank you all for the valuable input that has greatly accelerated my brief learning curve with boats, I hope some of the seasoned vets will help me along with my first attempt at building from a bare hull. It has been 4 mos, and I have 6 boats now, what have I gotten myself into...........
Before anybody says it, I DO use the search feature, in fact I've spent hours using it to get where I am already. That being said, I still have many questions and not enough time weed through and answer them all, and if I'm asking here, then I'm already searching as well.

I am lucky enough to be local to OSE, and since I've been going in there, there has been a DF Sniper 45" hull on the top rack, collecting dust(literally). It has some very minor cosmetic damage, so Steven said he'd let it go cheap($100) I thought it was a shame to let it just sit there, so today it finally came home with me Also have a Castle 2028 and Hydra Ice 200HV on the way from a member, and I have a spare 1/4 scale steering servo from my Losi 5ive-T.

I am starting this thread, hoping some of you will help me along on the build, and it will be more questions/advice for me than a build thread. If mods want to move it to Q and A forum that's fine.

First up, I intend to lay in some carbon Kevlar from Kintec, I think I've got enough info from searching to do that. The hull did not have stringers installed, though, and that is where I'm a bit undecided.

***If I go with wood stringers, does it need to be a certain type, or just standard Home Depot stuff? Should I do the complete carbon lay-in before stringers or anything else? How shall I go about installing them, it appears I would rough cut the shape, assemble with a motor mount, then fit to the hull befor finally epoxying/glassing, sound right?

Also thinking of carbon fiber stringers, but the sheets from Kintec only come in 300mm lengths I believe. Any advice on doing my stringers is welcome, ordering the carbon weave now..... SAM_0144.jpgSAM_0143.jpg

[dana]

Laying the carbon in first will make putting stringers in a heck of ALOT easier

[dana]

You can get thin plywood at craft stores like a.c. Moore. You can also laminate carbon to it to add strenth

[kevinpratt823]

You can get thin plywood at craft stores like a.c. Moore. You can also laminate carbon to it to add strenth

Didn't even think of that, thanks.

[dana]

Not sure if they will have pieces long enough for what you need, been a while since I've rummaged thru their stock.

[kevinpratt823]

Is it safe to say that a hull this size, with this big motor and 4 big lipos, NEEDS to have stringers/rails?(for rigidity/support) Or could it be built another way? All the pics of builds on this hull have rails, then there's the issue of a mount that fits this motor, most of the ones I have researched use rails.

[srislash]

Is it safe to say that a hull this size, with this big motor and 4 big lipos, NEEDS to have stringers/rails?(for rigidity/support) Or could it be built another way? All the pics of builds on this hull have rails, then there's the issue of a mount that fits this motor, most of the ones I have researched use rails.

I have a DF 35" and have found that the deck and hull flex quite a bit.Actually to the point of cracking my hatch.Granted this was when I was first setting it up and it was bouncing all over the place. BUT,With this motor/battery combo you may want to do some additional bracing,maybe like an AC Lazer(which I happen to have here). Pics in a moment.

[lenny]

Hey check with Peter aka Punisher 67,
He has 2 of them that he built so far that I know of.
https://forums.offshoreelectrics.com/...uot&highlight=
https://forums.offshoreelectrics.com/...ild&highlight=
https://forums.offshoreelectrics.com/...un-10S-2230-1Y

Make sure you get some good videos of it when done.

[Doug Smock]

Is it safe to say that a hull this size, with this big motor and 4 big lipos, NEEDS to have stringers/rails?

Absolutely.

[srislash]

Sorry about the mess of a hull there but it was a freebee

[kevinpratt823]

Hopefully my red carbon weave will be here tomorrow and I can lay it in this weekend. Can I use 3/16" birch plywood for stringers and bracing? And is 5" rail spacing the standard on a hull this size, or does it really matter? I wouldn't mind getting the rails built and installed this weekend as well......

[srislash]

Hopefully my red carbon weave will be here tomorrow and I can lay it in this weekend. Can I use 3/16" birch plywood for stringers and bracing? And is 5" rail spacing the standard on a hull this size, or does it really matter? I wouldn't mind getting the rails built and installed this weekend as well......

I think birch ply is good,I know that is what Andy(AC Boats) uses.I believe 5" is standard.I have two motor mounts coming for my Dumas and they are both for 5" rails.

[RaceMechaniX]

Take a look at the build thread I had a year ago: https://forums.offshoreelectrics.com/...100+mph+sniper

[kevinpratt823]

Take a look at the build thread I had a year ago: https://forums.offshoreelectrics.com/...100+mph+sniper

Thanks, I have come across that thread before, nice build! Would you recomend the flooded tube/strut over a stinger?, how about the front motor mount?
I have also considered a flooded tube with a stinger, if it is even reasonable........

[RaceMechaniX]

I prefer the flooded stuffing tube and strut, but if you slotted the stinger to allow for up and down movement on the transom then you can use it with a flodded stuffing tube. Steve Seebold is machining 1/4" stingers with slotted holes.

TG

[kevinpratt823]

I prefer the flooded stuffing tube and strut, but if you slotted the stinger to allow for up and down movement on the transom then you can use it with a flodded stuffing tube. Steve Seebold is machining 1/4" stingers with slotted holes.

TG

Any contact info on aquiring those stingers?
Also, do you think it is possible to use a slotted stinger WITHOUT having a flooded tube? Perhaps ovaling out the transom slightly just enough that the stinger plate still covers the whole area, allowing just a touch of adjustment? Hopefully I'll get started on something today. I have ordered a mount for 5" rails, can I ASSume that the 5" is exactly 5", so I could install the rails today, or should I just wait for the mount to show up to be sure?
This is the mount I ordered http://southriverrcboats.com/shop/ar...WRP-5-30F-0%26

[srislash]

I've got 5" to the inside of the rails on the AC and the Dumas Kevin.

[jcald2000]

http://www.intlwaters.com/index.php?...51#entry423002

Contact info

[kevinpratt823]

http://www.intlwaters.com/index.php?...51#entry423002

Contact info

I created an account, but it says I do not have permission to view that info, I'll try again later......

Thanks Slash. I mocked up a set of rails that should work, and put a layer of FG mat in the hatch with (Z-Poxy)finishing resin. I will definitely not be using the finishing resin the rest of the way, as it is pretty thick and tougher to work with. My father and brother are both commercial fisherman, and have been doing fiberglass work for many years, so I am going with some of thier help and guidance as well.

[dana]

You can thin epoxy with rubbing alcohol

[jcald2000]

Don't use RUBBING alcohol!!!, It has water in it and will destroy the strength of the epoxy.
If you have to use alcohol instead use CAMP STOVE alcohol, no water!, but still weakens the epoxy some.
Better to use the right epoxy, West or MAS from boating store.
MAT only has about 25% of the strength/weight of cloth at the same weight.

[RaceMechaniX]

You can thin epoxy with rubbing alcohol

You can thin epoxy with Acetone, but I would strongly suggest against using alcohol.

[RaceMechaniX]

I would not suggest using a slotted stinger without a flooded stuffing tube. The only way I have done this was by siliconing the tube exiting the transom to death. It worked, but required regooping every time you changed the height. The Stinger plate does not seal well so do rely on this for sealing water.

You can contact Steve Seebold at steveseebold@cox.net

[Punisher 67]

Tyler has a wealth of info ( RaceMechaniX ) You will like the Sniper it runs and corners like its on rails - I have two of them - What motor are you using

[RandyatBBY]

You can thin epoxy with Acetone, but I would strongly suggest against using alcohol.

I use isopropyl alcohol to thin my epoxy. It was recommend by one of my supplier tech adviser as a good way to thin epoxy for a thinner viscosity.

[kevinpratt823]

Tyler has a wealth of info ( RaceMechaniX ) You will like the Sniper it runs and corners like its on rails - I have two of them - What motor are you using

Power is a Castle 2028/Hydra Ice 200HV, on 10s paralell(consisting of a 4s and 6s in series on each side, all 5000mah/65c thunder power)
Thank you all for your input, I appreciate it greatly. Hopefully today I will get a run of fg cloth strip down each side at the seam, and see where I go from there. I am thinking of mounting the rails at 5-1/4" apart and glassing all the way up both sides. Tha glass will take up most of the extra 1/4", and I may be shimming the mount from there. I feel that this will also allow me a touch of leeway to get the motor where I want it(center). I already bought a quart of epoxy resin from west marine, that was the only thing my brother didn't have in his bin, which is why we used the finishing resin to start on the hatch, now I know better. Also will prob stick with cloth for the rest of the build.....

Should I consider offsetting the prop for torque roll on this build?

[RaceMechaniX]

A 1/4" of extra clearance seems very excessive. I only had an extra 1/16" for the carbon build up on the inside of the rails. I do suggest offsetting the prop between 3/16" to a 1/4" to the right for roll compensation.

[kevinpratt823]

A 1/4" of extra clearance seems very excessive. I only had an extra 1/16" for the carbon build up on the inside of the rails. I do suggest offsetting the prop between 3/16" to a 1/4" to the right for roll compensation.

Thanks, will do, I'll bring the rails in a bit, and plan to offset the shaft, so you don't think widening the rails to allow the option of shimming the motor a touch to the right is a good idea?

[RaceMechaniX]

I used 1/32" shim stock on each side of the motor mount and rails when mocking everyhting up. I glassed in the outside of the rails first, removed the motor and shims and then glassed the inside of the rails in. The shims accounted for the single layer of carbon cloth buildup. I set mine up with the motor centered. The stuffing tube was bent ever to slighlty to accomodate the offset strut.

I would not start in till you have all the pieces mocked up in place including steering servo, battery trays, etc.

[kevinpratt823]

I used 1/32" shim stock on each side of the motor mount and rails when mocking everyhting up. I glassed in the outside of the rails first, removed the motor and shims and then glassed the inside of the rails in. The shims accounted for the single layer of carbon cloth buildup. I set mine up with the motor centered. The stuffing tube was bent ever to slighlty to accomodate the offset strut.

I would not start in till you have all the pieces mocked up in place including steering servo, battery trays, etc.

Were your rails installed from the factory? Mine has none at all, so I'm making them myself. I will definitely mock up as much as I can before doing anything permanent. Tonight I reinforced the transom with a layer of combo, which has mat on one side and a heavy cloth on the other. Cut it to shape, laid it up/wet with resin on a peice of cardboard, laid it in and added resin, while patching in the edges with scraps of mat. I keep forgetting to bring my camera to my father's house, which is where I am doing this so far. Tomorrow I intend to lay in the carbon kevlar weave through the whole hull and up the sides, unless you(guys) advise another step first.............

Oh, any suggestions on the length of setback for a dual pickup speedmaster rudder?.........
edit, just saw that Tyler ran 6", maybe I'll start with that........