tried to build a light weight tub... and failed :(

[Marty Davis]

What about 1/8" Rhoacell foam with a layer of 6oz CF on each side? Weight the epoxy and lay it up with a bunch of weight and I guarantee it'll be lighter and stronger than any "natually occuring fibrous celluloid" product! :lol:

I do have some 2oz carbon fiber... are you vacuum bagging it or using peel ply? can you explain the process better?

joe is going to do an exparment.. his friend Dan Kramer sudjusted this to joe.. Get 1/64 ply,then coat one side with epoxy. Then put a layer of tissue thin fiblerglass cloth over the epoxy coated 1/64 ply side. then put that in between two pieces of glass add weight to it to help squeeze out any access epoxy. then out your pieces out for your rigger. was told it would be lighter and stronger then other rigger out there... ok I want to put this out here.. how light is to light??? we dont want to be blow over king like chip handover..At these races I see to many blow overs. We dont want to make them to light to the point where there no good to race them neighter.. then all that time and money was wasted for nothing :angry: another question you you guys? Do you think the 1/4"solid carbonfiber tube is to big and heavy for the.12?? Had acouple of guys told joe he should try 3/16 for the.12..

Don't worry about blow over. If you boat is setup correctly, you can't get it too light.

even if the boat is setup wright,,it will still blow over if its to light .. saw that in hobart and other races last year.

As I said, "If the boat is setup right"

 

[Tom Foley]

I guess there is a happy medium called " Racing Weight " which translates into being able to take some "Rubbin " and keep "Racing " . Light is one thing ..light and TOUGH is another .!

 

[julianconde]

Nessa Maybe you should talk to Marty Davis he builds light boats i never see them blowing off the water

 

[Bill Gibson]

Nessa Maybe you should talk to Marty Davis he builds light boats i never see them blowing off the water

YEP!!I learned this first hand by watching how Marty "fixes" an ill handling or flighty boat....a simple prop change per Marty on one of my boats transformed it from an ill handling airplane to a viable, competitve race boat...no strut changes, not an once of weight added...Martys statement is absolutly true....Tom does make a good point also...i think the challenge is to build the lightest boat possible that can stand up to the rigors of heat racing, but for sure the answer for making a race boat handle and stay on the water is not adding weight...Martys made a believer out of me in that department! SET UP IS EVERYTHING! Wish i knew half as much as he knows about it.......

 

[RickGlover]

I just completed my 12 jae. Without my strut in, it weighs about 12 onces. That includes my sponsons attached to brass 1\4 tubes, no epoxy or finish. 3\16 sides,1\4 transom, 1\16 bottom and deck. I built it out of spanish cedar it is very light and strong. We use it for exterior cabinets in the cabinet shop. I ripped down on the table saw and then ran it through the wide belt sander. It doesn,t cup up like maple does when you make it that thin. I built two 45 jae's out of it. Tub, sponsons, two coats of epoxy, stuffing tube installed 2 lbs. Thats 1\4 sides, 1\4 transom. and 1\16 bottom and deck. Its a good wood if you can find. Cabinet shops should have it or know where to get it.

 

[julianconde]

Marty is one of the best builders i have ever seen. i have held one of his riggers and WOW no weight at all he knows his stuff and hes a great guy..

julian

 

[TomMoorehouse]

I just completed my 12 jae. Without my strut in, it weighs about 12 onces. That includes my sponsons attached to brass 1\4 tubes, no epoxy or finish. 3\16 sides,1\4 transom, 1\16 bottom and deck. I built it out of spanish cedar it is very light and strong. We use it for exterior cabinets in the cabinet shop. I ripped down on the table saw and then ran it through the wide belt sander. It doesn,t cup up like maple does when you make it that thin. I built two 45 jae's out of it. Tub, sponsons, two coats of epoxy, stuffing tube installed 2 lbs. Thats 1\4 sides, 1\4 transom. and 1\16 bottom and deck. Its a good wood if you can find. Cabinet shops should have it or know where to get it.

Rick, please weigh us a 4" x 4" square of spanish cedar so we can compare it.

 

[Marty Davis]

Marty is one of the best builders i have ever seen. i have held one of his riggers and WOW no weight at all he knows his stuff and hes a great guy..

julian

You obviously haven't seen Keeley or Stu's boats....... I am a "HACKER" compared to them.

 

[Norm Doerr]

Nessa Maybe you should talk to Marty Davis he builds light boats i never see them blowing off the water

YEP!!I learned this first hand by watching how Marty "fixes" an ill handling or flighty boat....a simple prop change per Marty on one of my boats transformed it from an ill handling airplane to a viable, competitve race boat...no strut changes, not an once of weight added...Martys statement is absolutly true....Tom does make a good point also...i think the challenge is to build the lightest boat possible that can stand up to the rigors of heat racing, but for sure the answer for making a race boat handle and stay on the water is not adding weight...Martys made a believer out of me in that department! SET UP IS EVERYTHING! Wish i knew half as much as he knows about it.......

Yes. whenever we have had a perfect boat and all of a sudden it starts doing things like blowing off, darting.. etc. Out comes the digital angle finder and or a close look at the prop. Funny how things move around sometimes.

 

[Terry Keeley]

Marty is one of the best builders i have ever seen. i have held one of his riggers and WOW no weight at all he knows his stuff and hes a great guy..

julian

You obviously haven't seen Keeley or Stu's boats....... I am a "HACKER" compared to them.

Thanks for the nice compliment but in no way are you a "hacker", you've had some of the best RUNNING chit I've ever seen.

Never forget that near record run with your 60 hydro at the '96 Nats in Ft. Wayne, that thing was on a rail!

 

[RickGlover]

Tom, researched a little on Spanish Cedar. Its right at your finger tips with the internet. Its hard to find a piece of 4X4 Spanish Cedar laying aroud the cabinet shop. These are the weights i found on the internet. These weights are for a cubic ft. Spanish cedar 26 lbs,balsa 10.5, honderan

mahogany 34 lbs, maple 47lbs. shearing strength of spanish cedar 1200 lbs. It is related to mahogany and is considered a hardwood.

 

[dschigoda]

I looked up spanish cedar on the web - It is popular for use in making cigar boxes - because it absorbs and holds moisture so well.

I'm not sure this would be a desirable quality for boat building material? Since moisture = added weight, likely not.

 

[JRXHydros]

I looked up spanish cedar on the web - It is popular for use in making cigar boxes - because it absorbs and holds moisture so well.

I'm not sure this would be a desirable quality for boat building material? Since moisture = added weight, likely not.

NO..NO....you can use this wood...it is made to build real boats & skins for boat racing....seal your boat & play or go racing.

Joel

 

[moparbarn]

I looked up spanish cedar on the web - It is popular for use in making cigar boxes - because it absorbs and holds moisture so well.

I'm not sure this would be a desirable quality for boat building material? Since moisture = added weight, likely not.

NO..NO....you can use this wood...it is made to build real boats & skins for boat racing....seal your boat & play or go racing.

Joel

i agree spanish cedar & phillipine mahogany have been some of the woods of choice for boat building for years. before fiberglass became popular (yeah, been around boats that long), mahogany was becoming scarce due to the marine industry. with a properly sealed hull, water absorption a non-issue .

 

[dschigoda]

Aaahhhh. Thanks!

 

[Roger Hooks Jr.]

I really never paid "THAT" much attention to keeping a boat light. How much of a difference does it make in heat racing... I mean... I put driving above all else even if two drivers are evenly matched in skill and horsepower then it comes down to the luck at the start and who was in lane one right at 0 going full speed. Would a lighter (and I'm guessing it makes for a faster) boat give a guy that much of an edge to pull to the lead if he was unlucky enough to be at the line right at 0 going full speed if he was the boat on the outside?

Just asking...

I discussed with Andy I forget about how much heavier he said my paint work made my boat compared to a hull sealed with only resin. He said about 2/10ths of a second per turn. We run 6 laps so that's 1.2 seconds in a race. My thought was that is about a half a straith-way and half a turn behind. So I was thinking, that as fast as Andy could make a boat go if I was only a 1/4 of a lap slower than that. I'd still be faster than a whole lotta other people. And even a lap faster than a few more.

For 2 lap and straight-line I can see the concern. Every 10th of a second counts. But in heat racing seems like putting that thought and effort in stick time would produce a greater margin of success.

...But I could be wrong.

 

[dwilfong]

the total weight I think will make a difference in the amount of HP need to run a certain set up. Every thing will change with the weight. Prop choice and set up will show the true results.

Where you change the weight will also matter. less tail weight will change the set up.

When I built my swiss cheese tub it made it hard for me to nail down the set up. With a ski on the back it would pull a lot of prop but it was real picky on the sponson setting. the shingle air trap on the sponsons made the front real lite on the water. with a high AOA 4 deg and 3.8 deg it was real picky on the settings.

Had to take a break from it and regroup. :blink:

Will go back to rear sponsons and see how it sets up. Also will change the shingle air gap set up AOA lower.

But I think light is right on any boat.

David

 

[julianconde]

whats about trying to use really light wood and the put G10 to reenforce ???

julian

 

[TomMoorehouse]

G-10 is really heavy. I have i believe .015 G10 and it is heavier than 1/32 ply. I need to get to my workshop and weigh stuff up like I planned on doing..... to much OT right now.

 

[Chris Wood]

heres my 2 cents on the weight.. i try to build it as light as possible.. but i don't think that the weight isn't as important as other spects. i have had a 5lb OLD eagle sg run high 70's before

so prop's pipes and boat set up is WAY more important than weight.

get the boat right. the prop's right.. then nit pick the weight

chris