revell VIIc

[redboat219]

No need to replace the skeg mounted rudder piece if the kit supplied plastic part is OK. I've had the kit parts (including the plastic stern plane and bow plane pieces) on my operational Type-7 and have been operating that model for nearly four years now without breakage. Don't find boogie-men where they are not.

always assumed they'll be too fragile like the deck railings.

s

[satlite440]

well mine was broke so i kinda had no choice.. but it is a war boat.. casting lead is easy and fun for me as i do have the resources of my shop.so it's a little easyer

[satlite440]

well try 1 epic fail. mould to deep makeing another tonight.heres what came out not so good.gonna keep trying.. ackkk just broke the log positivegoung to have to start from scrach tomarrow... such is life...the saga continues..

[satlite440]

not that i'm planning to give up.but my question about the lead shot and epoxy is i'm assumeing the boat must be together and you would add an amount of shot add subdriver fitted out with the saddle foam.and place it in the water.then once you have the right amount then you would mix the epoxy and add the desired amount of shot you found was ideal for your paticular boat at submerged trim? vital spark do you know about how much weight ball park you have total? thanks.. 3rd set of positives drying.. gotta slow down and enjoy this in stead of flaterateing it(for those who haven't heard that term,almost all auto tec's are paid whats called flat rate if a waterpump pays 2 hrs and you do it in 1/2hr you just made 1&1/2 hrs profit due to the fact you have done enough of them to be that fast.however if it takes you 6 hrs to do the same water pump you still only get paid for the 2 hrs and the other 4 are your free labor and unpaid. so we are paid by the job.. i know of no other trade where you go to work and don't know how much you will make a day.. might work all day for 2 hr pay,might make 12 hrs in an 8 hr day if the stars alighn just right..) so going to slow it down matter afact i just had an idea and will try it tomarrow

[Albion]

I got hold of some lead fishing weights, the ball type ones which were slightly smaller diameter than the keel 'trench'. I filled the trench with balls and then poured epoxy in to lock them in. Unfortunately it was too much, as im also using brass for my A frames and rudders supports. (Also my brass props and 5mm shafts are heavy) I was lucky that i was able to dig some of it out again. I would go easy on how much lead you put in, maybe fill the centre section first, then try for trim, and add some more as needed.

http://forum.sub-driver.com/showthread.php?1485-Type-VII-Build

I guess the plastic kit parts should be strong enough if you are careful, but i'm not! and more than once they have protected mine.

[vital.spark]

The cast birdshot and epoxy weights were supplied seperate and were removable. For the type VII I found pictures/text somewhere on the Forum of an installation that David did and used this as my starting point. I had to remove and cut off small amounts of the weight as I did my trimming. I also had to file a bit off the sides so the weights would just slide in.

Perhaps David can step in now and tell you if the keel void was covered with a form of mold release or what ever so the epoxy wouldn't stick to the inside of the hull and could them be removed?

For the amount I used, it was about the forward 3/4 of the keel void but this would depend on your battery weight and your exact location of your Subdriver in your hull. IF YOU WOULD SPEND THE TIME AND DO YOUR RESEARCH, YOU'LL FIND THE ANSWERS HAVE ALREADY BEEN COVERED ON PAST FORUM POSTINGS!!!

Regards,

Myron

[He Who Shall Not Be Named]

Myron, kick his newbee ass! (Myron's an old hand at this, listen to the man).

As he said, the bird-shot idea is a viable one. Here's how you do it so it's removable:

1. wax the entire inside keel cavity -- this constitutes a release agent that will keep the cast epoxy-lead ball slurry from sticking

2. mix up some slow cure epoxy or polyester resin and pour in lead shot, you want to achieve a high resin-to-shot ratio, i.e. more resin than shot.

3. pour this resin-lead ball slurry into the cavities and let cure hard

4. pry the hardened weights out -- but be careful, the shot greatly reduces the shear strength of the cast weights and they will crumble in your hands if you apply too much twisting or shear force on them -- flexing/twisting the hull will help to un-stick the resin encapsulated weights from the keel cavity.

You now have removable weights that can be cut up and placed inside when you get to the fixed weight and foam stage of final trim.

As Myron pointed out, you wont' need the entire length of cavity filled with fixed ballast weight.

Ta-Da! (the crowd goes wild!)

David

[satlite440]

had a better idea to day and will post pics tonight and will explain then..overengineered the plan that was the fail....

[satlite440]

ok 1st fail,didn't measure the amount of lead poured.2nd fail mould too deep..got a good idea of how much as 4 oz of lead is. working on a mould that is not as deep and has a removable bottom to allow weight to be pushed out if this attempt fails..tried crisco as a release agent will try car wax next if crisco fails. also need to scoop/bevel the upper edges to make a better release . i think this one will be in the ballpark as today used only 4oz per pour. now i think have a workable ft and rear keel mould but have been down this road before...



as a side note since i still have not joined the hull halfs together what kind of wax should i use?would car wax work or bee's wax? and what kind of epoxy or polyester resin should i use?do you have a preferance. i used a 24 hr loctite 2 part epoxy to fit in the bulkheads in the boat i have would that be ok?just have scary visions of my hulls being stuck together trying that since there are some small gaps with the hulls held together with clamps.. but i would give it a go....thanks shane

[Avera]

A one pound scuba diving weight bag contains lead shot and is cheap to buy. I used silicone adhesive to secure the lead shot to the void. A little tricky, but I did it in layers adding the adhesive first then adding a couple of ounces of shot more towards the bow. Let it dry and added a second layer (total 8 ounces of lead) and then a thin top coat of silicone to seal them in. This allows me to remove excess weight later on.

[redboat219]

i used a 24 hr loctite 2 part epoxy to fit in the bulkheads in the boat i have would that be ok?

i remember somebody here told me you don't need to install them, not much space anymore for the 2" SD.

[He Who Shall Not Be Named]

ok 1st fail,didn't measure the amount of lead poured.2nd fail mould too deep..got a good idea of how much as 4 oz of lead is. working on a mould that is not as deep and has a removable bottom to allow weight to be pushed out if this attempt fails..tried crisco as a release agent will try car wax next if crisco fails. also need to scoop/bevel the upper edges to make a better release . i think this one will be in the ballpark as today used only 4oz per pour. now i think have a workable ft and rear keel mould but have been down this road before...



as a side note since i still have not joined the hull halfs together what kind of wax should i use?would car wax work or bee's wax? and what kind of epoxy or polyester resin should i use?do you have a preferance. i used a 24 hr loctite 2 part epoxy to fit in the bulkheads in the boat i have would that be ok?just have scary visions of my hulls being stuck together trying that since there are some small gaps with the hulls held together with clamps.. but i would give it a go....thanks shane

Don't install the bulkheads in the hull! You have to spring the thing open to install/remove the SD! Rip them out if you put them in already.

I don't care what kind of wax you use or if it came from a Bee's butt or is synthetic. Any thin resin that can be catalyzed to polymerize to a solid will do. I use West System laminating epozy resin for encapsulation work.

David

[satlite440]

should have been more clear.. i used the loctite epoxy on the target boat

[redboat219]

Shouldn't ballasting and trimming be the last few thing you need to do, not in the start of your build?
There are still a lot things you need to put on that can affect how she'll sit in the water.

[satlite440]

yes your right redboat219.however since the weights&foam set is not available on the caswell website at this moment in time i am makeing my own..i read somewhere that fitting the foam was easyer when the hulls were apart as to fitting them into the saddle tank void nicely and i want to do that.. as far as the weights go. i was attempting to cast a mould for the keel weights that would be removable and sectionable for when i get to that stage. i was happy with the weights i cast to day but am going to try the epoxyslurry/fishing weights with wax now... i don't mind experementing.. also i got some foamular pink at the local hardwere store and will set the depron aside for something else. sorry about the confusion about the "boat" in the future i will call the surface runner i built the "targetboat" that one was the one i epoxyed in the bulkhead that holds the moter/drivetrain...and that that was the only experence i had with an epoxy.. as a side note is the qucikwood dave talks about made by loctite?


thanks for your patience with a beginner

shane