MAC.84\CF Rigger

[MikeP]

I decided not to restore the old Crapshooter, going to build a big brother for the 3.5 CF rigger. I enjoyed posting pictures as I built the last one and would like to do it again.

First picture, this is the mold for the hull in pieces.

http://69.27.9.16/mikep/cf90/pieces.jpg

The mold was Hammerheads idea and is very easy to build and use. It has mylar glued to the mold surfaces this will give a nice glossy finish.

This how I made the mold for the hull

The wood is particle board. It's cheap comes in smaller pieces for shelves and is really flat. Other wood I have used is always warped. I cut the pieces the size I want the hull to be. Drill holes and screw on the sides. Make a block for the angle of the bow. It should be 50% of the height of the hull side walls. For the bottom former of the hull I used fiber board, cut it to fit inside the hull. The fiber board will collapse in the vacume bag so I used some foam to support the fiberboard where it angles up. Use 3m 77 spray adheasive to glue mylar to the mold. disasemble the mold, glue on the mylar drill out the screw holes sand the mylar flush with the edges and reasemble.Take extra time making this mold, make sure it is straight and has no gaps. It can be used many times. This can be either the top or bottom. For the other half you will need to shim it out thickness of the hull sides or cut it smaller. Hammer made two molds one a little wider than the other.

-MikeP

 

[MikeP]

Here is the mold all screwed together. It just needs some mold release wax and it's ready to use.

www.ad.kengarff.com/mikep/cf90/mold1.jpg

-MikeP

 

[TomMoorehouse]

test reply

 

[Mike Bontoft]

Hi Everyone (first time posting here)Thats great news mike, A few days ago I ordered the vacuum bagging equipment and plan on building a gas CF rigger For my new Zenoah 260 , Your 3.5 got me interested. Can you show as much detail as possible. After running the 3.5 I spose you have a few improvements you want to include on the new one.

 

[MikeP]

Mike,

I was planning on a little more detail, If I miss something you need let me know.

Be sure to share your ideas as well.

I made a 10x21 sheet last night, instead of a nice glossy finish on both sides I used peelply on one side. I should be able to glue it to the foam without sanding.

It was 20 deg. F here last night garage temp was 55-60F, I wrapped the plate and vacume bag in an electric blanket and it worked really well. I think I will always use the electric blanket.

-MikeP

 

[Mike Bontoft]

Mike

The hydro I plan on building is for SAW events only, The design of the centre tub is more like a wing shape. I am going to take the design from the one jourge used to break the 100mph electric hydro record. The design has the front sponsons extended way in front of the tub. A very neat design.I am sure the tub can be made in the same fashion as yours, just more shallow. Although I have been racing for a few years this SAW stuff is very new to me, so any help from anyone would be much appreciated. Thanks

 

[MikeP]

The big brown truck came yesterday. I got Carbon cloth from Carbcom.com. I also got the 1/2 inch carbon booms, breather cloth, peelply from Aerospace Composites.

Here is a picture of some tools I use.

http://69.27.9.16/mikep/cf90/olfa.jpg

The olfa mat and rotory cutting tool is the only way to go. You get them from the fabric store.

-MikeP

 

[MikeP]

This is a picture of the mold tool I use to make angle stock for mounting stuff in the radio box.

http://69.27.9.16/mikep/cf90/angle.jpg

Here is how I make the angle stock.

I have a piece of foam notched to hold the alu mold while in the vacume bag. Wax the alu. mold with mold release. Pour on some epoxy and then the layers of cloth I use 3. Spread out the epoxy saturating the cloth. Cover it with wax paper then put either a piece of alu. angle to force the molding into a sharp inner edge or use a dowell to get a radius. Put it in the bag. Suck over night

-MikeP

 

[MikeP]

This is the finished 10x21 plate. The peel ply side will save alot of time sanding. I am going to use it alot more this time on the surfaces the are going to get joined or glued.

http://69.27.9.16/mikep/cf90/plate.jpg

Here is step by step how I make plates. The plates will be cut and glued to foam core front sponsons and the foam core bulkheads.

I use a piece of glass, wax it good with mold release. cut 3 pieces of CF to the size just smaller than the glass. Mix 4 pumps of West System epoxy with slow cure hardner for a 10x21 plate. Spread some epoxy right on the glass and spread it around. Lay the first layer of CF and rub it down good with a body filler spreader. Make sure the CF is saturated completely. Pour more epoxy and then the 2nd CF layer rub it down good again make sure it is completely saturated do the same for the 3rd layer. Now apply peelply and rub it down. Leave the peelply off if you want both sides glossy. Last lay down a piece of mylar to protect the bag from epoxy and help flatten out the cloth evenly. In the bag lay a piece of breather cloth this helps the vacume reach the far end of the mold and soaks up epoxy. Set the glass on top of the breather cloth. I leave the vacume on over nite. Clean up tools with Rubbing Alcohol.

-MikeP

 

[TomMoorehouse]

peel ply makes the parts stronger/lighter as well right???

I'm glad to see you can still post pictures. you could also have them show up on the forum by using the (img)URL

(/img) tags..... but replace( & ) with [ & ]

 

[Twin_k90]

The big brown truck came yesterday. I got Carbon cloth from Carbcom.com. I also got the 1/2 inch carbon booms, breather cloth, peelply from Aerospace Composites.

Here is a picture of some tools I use.

www.ad.kengarff.com/mikep/cf90/olfa.jpg

The olfa mat and rotory cutting tool is the only way to go. You get them from the fabric store.

-MikeP

Mike,

do you have a picture of the booms you got from aerospace?? i got some they are black but they are glass not carbo, they broke in a very spectactular way at about 90mph down the front straight!! my twin is probably harder on the booms than you boat will be tho!

also what is peel ply?? i dont have a clue what that is! also when you made the servo mounts out of carbon, how many layers did you use? what resin etc??

Dale

 

[Ian Inverarity]

Mike,

A word of caution about using the peel ply and not sanding: when most epoxies cure a waxy film forms at the surface, irrespective of the finish. I have read elsewhere that this film can be removed by scrubbing with hot soapy water and a scourer, which might be easier and cleaner than sanding.

I once epoxied tank mounts into a hull that was made with epoxy resin. The sections I glued to were fiberglass and had the weave pattern which I thought would bond well. The first time I flipped the boat the tank mounts broke away and I had to dig the tank out from the bow of the boat! I had not sanded or scrubbed the area where I glued the mounts and they broke away cleanly despite the surface texture! :

Good luck with the carbon boats! They look super cool!

Dale: see if you can find someone to make you kevlar and glass booms, they should be pretty tough.

Ian.

 

[Twin_k90]

Ian,

i have had that problem when not sanding as well,

also the place in QLD will make carbon/kevlar booms for about $80 now

i have 2 sets of solid 6061 ones at the moment, so when they bend i will get some carbon/kevlar ones done.

Mike.

have you thought of making a plug and pulling a mould off the boats and doing them carbon like that??

 

[MikeP]

Just happened to have a picture of the booms. The large tube is .60 O.D. The small one fits inside it. I also wrapped the outer tubes with 4 layers of kevlar 1.4oz wt. on the 3.5 and will again on this one. I don't on the inner boom tube so they will break first and not destroy the hull or sponsons.

http://69.27.9.16/mikep/cf90/tubes.jpg

Peelply is a porous nylon fabric you lay it up with the cloth and all the excess resin is pulled off, making it lighter. You pull it off after it cures, it leaves a rough texture.

I use three layers of 5.7 oz fabric with West Systems Epoxy. The hull sides will be doubled when joined ending up with 6 layers. 2 layers is useless, 4 would be good for extra strength. 3 layers is about .034 thick.

Thanks for the warning about the waxy film

 

[Ian Inverarity]

Mike,

Does the vacuum bagging help the carbon go into tight corners? Where did you get the vacuum bagging equipment?

Ian.

 

[Twin_k90]

Just happened to have a picture of the booms. The large tube is .60 O.D. The small one fits inside it. I also wrapped the outer tubes with 4 layers of kevlar 1.4oz wt. on the 3.5 and will again on this one. I don't on the inner boom tube so they will break first and not destroy the hull or sponsons.

www.ad.kengarff.com/mikep/cf90/tubes.jpg

Peelply is a porous nylon fabric you lay it up with the cloth and all the excess resin is pulled off, making it lighter. You pull it off after it cures, it leaves a rough texture.

I use three layers of 5.7 oz fabric with West Systems Epoxy. The hull sides will be doubled when joined ending up with 6 layers. 2 layers is useless, 4 would be good for extra strength. 3 layers is about .034 thick.

Thanks for the warning about the waxy film

Mike those booms are the same as mine they are glass not carbon! they lasted about 4 days at the pond on my twin, they seemed to break where the holes were drilled for the bolts to hold them into the boat, i have enought to make 8 more booms so im going to try them with using some AL tube cut in half so they are supported the whole length in the tub. with your boat being lighter you shouldnt need to do all this to them!!

so you lay the cloth and resin on top of the peelply?? and it allows the resin to drain out? sounds like i need to get some to try,

also have you thought of sandwitching some hard foam or ply in the side of the tub?? we sandwitch the sides of our twins with ply the layup is like this for the sides

1 layer of glass

1 1/4" ply

1 kevlar.

the bottom of the tub is only 1 layer glass and 1 layer kevlar, i put some carbon/kevlar weave in some spots to stifen up

Dale

 

[MikeP]

I got my vacume bagging supplies from Aerospace composites. They also sell a video that shows you how to vacume bag. I have to vacume bag I am not skilled enough to lay the fabric without the bag holding it all together. Here is the URL for aerospace composites.

http://www.acp-composites.com/ACP-CAT.HTM

The tubes I have are carbon.

I have had them break on my .15 rigger where I drilled the holes to mount them. I dont drill holes in the booms any more. Hammer showed me how they do it in Japan.

-MikeP

 

[MikeP]

I have had several requests for step by step details. I have added them to the first posts.

Thanks for your interest.

-MikeP

 

[Twin_k90]

http://www.acp-composites.com/ACP-CAT.HTM

The tubes I have are carbon.

I have had them break on my .15 rigger where I drilled the holes to mount them. I dont drill holes in the booms any more. Hammer showed me how they do it in Japan.

-MikeP

Hmm they look identical to mine, mine may be carbon as well, who knows!!

ill ask hammer how he does it !

 

[Mike Bontoft]

Hi Mike

Looks like your moving right along , I'm still working on my new(large) workbench. However I did receive my vacuum bagging kit today, I did not order the pump because I have one for evacuating A/C systems that seems to match the requirements, I have orderd a vacuum switch from McMaster carr and I am going to use a portable air tank so the pump does not have to run continuously. Ready to start construction soon though.