Kevlar
 

I need to make by myself the fuel tanks for a project I'm working...and wonder where can I order kevlar and the adequate epoxy for that?
Thanks,
MS

RE: Kevlar
 

In the states.Wicks aircraft supply.They have the kevlar and the west epoxy system. I have used it to build floats for full size aircraft and to patch holes that Skymaster put in the wrong place on my 1/6 f 16 fuel tanks worked well for me.
Joe

RE: Kevlar
 

In the states, there is also http://www.acp-composites.com/ Don't forget to get the special tool to cut it. Normal scissors won't work.

http://www.acp-composites.com/acp-sbwf.htm

http://www.acp-composites.com/acp-ta.htm


Arnaud

RE: Kevlar
 

Thanks for the data.
Learned something new today about the tool for the cutting...
Regards,
MS

PS. How many Ounces x Square Yard fabric should I choose?

RE: Kevlar
 

You need about the same weight of resin and fabric. ;)

RE: Kevlar
 

which tool are you guys using the ceramic scissors? you can use regular scissors just have to grind the edje 90deg to the cutting surface.

RE: Kevlar
 

Get a crow foot weave Kevlar, The plain weave can be hard to get around tight radius corners, Regular good quality scissors work fine for cutting Kevlar, in fact a cheap pair will work , you just need to run the blades on a grinder 90 degrees to the blade to give the blade some tooth so the kevlar won't slip out while cutting, do a search on google for Cutting Kevlar fabrics.

RE: Kevlar
 

Kevin Whitlow had a great suggestion on cutting Kevlar; go to the store and buy several pairs of really cheap scissors. They will not last very long, but a couple pairs might get you through a set of tanks.

I just did a set of tanks using 3.3 oz Kevlar. I used 3 layers, which was just barely enough, 4 or 5 layers would have been better (but I ran out of fabric).

RE: Kevlar
 

Ok...I guess I´ll buy a few cheap scissors.
Did you applied all layer at onces?...or each layer was a new epoxy mix?
How about using several layer of 1.7 oz intead of a few of 3.3?
Does this material remain well at the mold corners? ...I´m planning use the positive mold technique...
Tks,
MS

RE: Kevlar
 

Cheap grocery store scissors will work on 3.2oz Kevlar, but they have a lot of trouble with the 5.6oz stuff.
Ceramic coated scissors work best for the heavier stuff. Just be sure that you don't use your expensive ceramic scissors to cut anything except Kevlar, as soon as you do they will be useless. (guess how I found this out?)

Here is the thread I did on making tanks several years ago:
http://www.rcuniverse.com/forum/m_13.../tm.htm#132449

Steven, you might recognize the molds.

RE: Kevlar
 

Miguel - for holding material onto the tank ... I was going to spend the money on a vacuum system, but the guys at ACP told me to just use indutrial grade "Cling Film" and stretch that around the tank while waiting for the resin to set.

See http://www.rcuniverse.com/forum/fb.asp?m=3538375

RE: Kevlar
 

Wao...I was thinking on that Gordon.
My intention is to make the molds with foam...and wrap them with the same plastic film use for storage food. Then apply the layers of kevlar with epoxy, to finally use the steaching film to hold everything in place and tigh...
What do you think?

RE: Kevlar
 

If you use cling film on the inside, you may find that that sticks to the epoxy. I'd try a test piece first, and experiment with spray-on way on top of the inner film. For the outer film, apply peel-ply first.

RE: Kevlar
 

Kevin,
I saw your thread...nice work.
Can you give more details about the mixture of cabosil and resin for the corners...?
MS

RE: Kevlar
 

Miguel,
The stretchy film as a mold covering will probably work fine as long as your tanks don't have any concave surfaces. If there are concave surfaces you will have more luck covering the molds with a low temp iron on covering like Econokote. That is what I used to make the molds in the thread I posted below.

The nice thing about the Econokote covered molds is that they can be reusable. Those particular molds have now made three sets of tanks and are still in good condition.

The stretchy film for holding layers in place is a good idea too.

RE: Kevlar
 

You are right...
Can you tell me more about the carbosil?

RE: Kevlar
 

Hmmm,
I usually just guess at how much cabosil I will need for the job, pour it into a mixing cup, then add mixed resin until it is about the consistency of paste (the stuff pre-school kids use for art projects). I think the mixing cups I use are 3 ounces, and I usually fill them about 1/3 to 1/2 with cabosil then add resin.

You only want to use enough to make a small fillet in the inside corners where the cloth will not make contact with the mold. If you use too much it will only add weight/thickness, and weaken the part. If you use too little you will likely get air pockets.
Should be just enough to form a little "ramp" for the cloth to follow up the corner.

RE: Kevlar
 

Excellent....I think I have the general ideal to go for it.
I´ll keep you posted...
Rgds,
MS

RE: Kevlar
 

Miguel,

I buy kevlar cloth from this selles on Ebay.
http://cgi.ebay.com/1-7-OZ-KEVLAR-FA...QQcmdZViewItem

I make the kevlar tanks for my Vigilante.

I use balsa plugs and poliuterane primer to finish. Aply the orange gel mold and fiberglass with resin to get molds. The pics show better my process.

When ready I post pics here.





Regards,
Fabio

RE: Kevlar
 

Nice work Fabio and thanks for the contact info for the kevlar.
Best Regards,
MS

RE: Kevlar
 

Kevin how about hybrid carbon/kevlar weave, you say not to cut anything else with the ceramic scissors what would you use to cut through two diffrent kinds of fabric?

RE: Kevlar
 

Miguel,</p>

I finished my tanks months ago but only now i can post the pics.</p>

[img]C:\Users\Fábio\Desktop\Jets\Vigilante\Anuncio\dcs0 1232[/img][img]C:\Users\Fábio\Desktop\Jets\Vigilante\Anuncio\tank[/img][img]C:\Users\Fábio\Desktop\Jets\Vigilante\Anuncio\3[/img][img]C:\Users\Fábio\Desktop\Jets\Vigilante\Anuncio\5[/img]</p>

RE: Kevlar
 

the pics...</p>

http://img196.imageshack.us/my.php?image=molds.jpghttp://img51.imageshack.us/my.php?image=tankb.jpghttp://img195.imageshack.us/my.php?image=49251368.jpghttp://img194.imageshack.us/my.php?image=79135511.jpg</p>

flight video:</p>

http://www.youtube.com/watch?v=Asx3ybz_sOs</p>

</p>

RE: Kevlar