How would you guys deal with this mould?

General Composites Discussions Composites Talk
#1

Ok here’s the first mould I made, its for a motorcycle dash unit, I know its not pretty :smiley:

I made the plug from wood then to make the mould coated the plug with RM2000 tooling resin then FG mat to back it up.

I tried laying up some carbon mat into it but I just couldn’t get it to conform to the curves if it was in one piece without it bunching up in the corners. I tried vacuum bagging but left the vacuum on for too long and sucked most of the resin out of the fabric. I then tried to lay the mat in, in several sections but came across the fraying edge problems.

After that I tried laying in a piece of carbon/kevlar mat and it seemed to conform much better, I also used the previous failed carbon piece (from the vacuum bagging) on the inside to push it into the corners. The only problem I had was a few dry spots on the resin which I suspect was caused by not soaking it enough, I flatted it off with sandpaper and wet sanded it and next is to give it a few coats of auto laquer.

How would you guys have dealt with this mould? I don’t have a powerfull enough vacuum pump for resin infusion so thats not an option. I thought the angles might have been too tight but I’ve seen plenty of other similar parts people have made.

Thanks in advance
Andy

Mould 1

Mould 2

Part

#2

Honestly I dont see why you are having such a problem.

Perhaps you could brush some resin in the mold and let it start to B stage and it will be tacky enough to hold the cloth. Let it kinda cure and the cloth is locked in and resin in from the back side. Its not a structural piece so what do you have to lose?

Try working with Texallium…that shit is unbearable for most parts. It looks cool but sucks when it comes to making anything other than a clip board panel.

#3

Clipboards…I resemble that comment! :smiley:

On the mold, it doesn’t look like you used any surfacing tooling gel coat as you can plainly see the mat (Fiberglass mat is the strand stuff) reinforcements. In my classroom, any black gel coat is tooling gel coat as most parts are colored gel coated…that way you can tell what is covered and what has not been covered.

I doubt if Carbon Fiber has ever been made into a “mat” unless you are using that term as for Material?

I doubt it you will get a single, uncut piece part from this shape and it is something to think of the next time in the planning stage before making the plug / master.

For the fraying, try using a high quality painting masking tape on the back side and cutting thru the center of the tape to get fray proof cuts? Practice on scrap pieces first.

Hybrid has the right idea of using a clear gel coat (or lamination resin with Cabosil or a thickener in it) and letting it “B” stage before laying the first reinforcement into it. One layer of CF and at lest one or more of thin Fiberglass should be fine for this item.

Are you using PER (Polyester resin) or Epoxy resins?

#4

Thanks for the replies guys.

It seems like I’ve completely misunderstood how this RM2000 tooling resin is meant to be used. I thought it could be used in the place of gelcoat to make up the outer layer of the mould. However it looks like its supposed to be used on the subsequent layers with the fibreglass mat. If anyone is interested there are some details here and I have about 4.5litres for sale!!! http://www.nida-core.com/pdfs/nord_applications.pdf

Sorry, yes I meant carbon material rather than mat.

I’m using epoxy resins, I think I’m going to scrap this mould, I’ve bought some gelcoat now so I’ll take some more time and build a better one.