3in tube for male mould

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#1

Hey all.
Im waiting on tooling materials to come in for a different mould so I wanted to ask some questions in preparation for a new mould I would like to try.

I have a 3" straight steel tube, I think if i read some instructions on this site I can figure out how to make the part from regular cloth.

My question is this: I have this piece. Pictures. It has a slight raidus in it. What I want to know is: can this be used as a mould to make a part from? How would you make this part?

Im assuming wet layup is the only way for these items. Or prepreg…

Is there a carbon fiber supplier for 3" and 3.5" diameter filament wound or another winding that would work for my tube?
I don’t really even need the carbon fiber for this, do they have a supplier for colored kevalr? or even color fiebrglass? that is cheaper than fiberglast.com
Can a dye be added to regular resin and used to color the kevalr?–> based on the wet layup technique…



thankx

#2

I would make that pipe joint ( pipe pictured ) a two piece mold. You can use fiberglass cloth style 3733 or 7533; and style 7500 would work well. www.fiberglassupply.com sells them. Carbon fiber twill would be real easy to work with. kevlar has no strength on it’s own.

If it’s colored fiberglass you want you can try www.sollercomposites.com … they are in the US.

#3

I would suggest using a bladder/smart mold for something with a radius. A 2 part might work as well since it’s a short radius.
The layup can be pre-preg, wet layup, VARTM, braided sock, or filament wound. All depends on what you want.
What is it for? That will determine what material you need to use. Glass, CF, and kevlar are all different animals, all with their own purpose in life.

#4

This piece I am simply experimenting with is part of an intake tube for a automobile. I am just experimenting with this, I dont plan on producing the part.
I want to practice with tubes and such.

No real strength is needed here. Carbon fiber looks best, but some color fiberglass or kevlar may look even better.

What type of two piece mould is being referred to here? Are we talking a female mould that is split down the center of the tube? That seems like alot of work…

Can I make my own bladder mould? or have a bladder mould made?
Couldn’t I use some filament wound material and wrap a mould with the radius in it?

#5

the best way in my opinion, for a more complex pipe than this, is to use aquapour. In that case, you would make a two piece mold of the pipe, with one end closed, open it, remove the plug, close it again, fill it up with aquapour. then, when it has cured, take the cured aquapour and cover it with carbon and vacuum bag it. then wash away the aquapour, it dissolves with tap water. if you want to experiment, there was a tutorial (on this forum? or another?) that described a nice (however complex) method to make carbon piping using a two piece mold. it all depends on whether you care to keep the absolutely same diameter on the product. if it’s just an intake pipe that connects with hoses, 1-2mm won’t be a bother.

#6

Ok, I understand the part.
You can make a silicone rubber mold with a hole in the middle. This way, you can have room to wiggle the part off the mold. (Mostly everything does NOT stick to silicone), and the hole in the middle will let you collapse the mold to wiggle it out. (Think a REALLY thick walled pipe.)
For that, you can add some extra length to your part with tape/plastic sheeting, and just pour in the silicone rubber. THen insert a dowl in the middle. After it cures, you can pull it all out.

Aquacore also works, but that will need a 2 part mold. ie: femalemold split in half with flanges to clamp. Then you just pour/pack in the aquacore. (then bake it to dry it, wrap it in release film, wrap with your composite material, cure, dissolve aquacore, etc etc)

As for layup, you can still use anything. Filament winding can be done by hand, but is NOT easy, and doesn’t look that good when done. You really need a winding machine to do it. Otherwise, check out the Sticky thread about making CF tubes. The idea is the same.

I have used Dunstone heat-shrink tape to compress all my tubes I’ve made. Some people also wrap electrical tape (backwards!!!) around the wet part, and then poke holes in the tape to let excess resin escape.

#7

i just got a stupid idea. how about carbon fiber tape, winded around the tube like electrical tape… ? would look ugly i guess, but it makes fitment easy!

#8

That works too, instead of full sheets of fabric.

#9

It seems like braided sleeve would be the ticket.

#10

this is what I have been thinking myself. I was hoping someone would know a company that sells something like this.

I have used aquacore b4. it is not ideal for production use.

I was interested in a bladder mould but it seems like not too many people have much to say about the bladder moulds.

#11

http://www.solarcomposites.com/composites/carbon%20fiber%20sleeves.html

#12

many people make sleeves. Bally RIbbon mills, 3xtex, fabric development, etc

Bladder molds in production runs are easy to use, since you have all the right systems and setup. But sometimes it’s the only way to go. If you do the silicone bladder (or air bag bladder), and a female mold, it’s great. You just need a way to keep it inflated (or as I mentioned above, just a dowl of sorts.
Smart bladder molds are complicated. You heat and form the bladder in a mold, wrap/wind your composite to the shape, cure, and heat up the mold to pull it out. Something like that, but requires lots of molds just for one part…but if the part is complicated, it’s the way to go I think.

#13

For a simple air intake, wouldn’t using the 2-piece mold be best? The idea of a bladder set-up is nice but i feel is excessively complex for the part. Since there is no real pressure flowig through the part, the structural integrity that a 2-piece mold will provide should be enough…

#14

Well yes, IF the tube is big enough that one can get a vac bag sucked down into it, or do some weird bagging setup.
Hmm…2 tubes…one on the outside, and one on the inside…that might work. (i’m talking soft bag tubes obviously, not a hard tube like pvc!)
That way, the inner tube will provide a flexible pressure source to the inside of the tube, and the outside bag around the mold will provide the complete vacuum bag seal, and pressure against the outside of the mold. I like that idea!

But if you plan on doing a wet layup with no bag inside a tube, that would be hard, even for a non-structural part.

#15

Very Nice Find. Thank you sir for your comtribution.
Now, only if they had a 3.5" Diameter tube.

#16

Very Nice Find. Thank you sir for your comtribution.
Now, only if they had a 3.5" Diameter tube.

#17

Can you post some links for me, possibly the direct link to the page with the sizes?

#18

Just heard back from Solar and heres some interesting info.

There 4" diameter sleeve can shrink down to 2", so in order to hit my 3.5" desired size, I would need the 4" hybrid sleeve.

Im excited to try his out. It is a very interesting material and procedure to perform. Almost seems too easy! Ill update once i get the material and give it a try…