Hi Guys.

 

Looking to infuse this part. Please have a look at diagrams attached.
I had an unsuccessful first infusion other day. My setup was the standard easycomp spec of resin feed spiral wrap all along length (but not the 2 ends) vac connection opposite with the 2 layers mesh for airflow. Part covered in infusion mesh. Main issues were resin barely making it to far ends (not surprising) and resin getting to vac line way before far ends had infused (again unsurprising)

 

So my thoughts were:

 

Option 1 (Fig. A): Abit of the first method , plus the standard centre feed infusion method. I would run spiral wrap wrapped in peelply, rather than double mesh along the length and also 2 ends.

Resin feed along length but maybe stopping short (x dims?)To try keep resin away from the vac spiral and possibly into the vac line before all part is completely infused, maybe not an issue tho!

 

Option 2 (Fig.B): Same standard set up but resin feed along length and also the 2 ends, plus maybe even taping up the the wrap partially along length to ensure plenty resin gets to the far end. Plus also stopping mesh short around the vac inlet to slow down the resin feed to remedy the problems i had.

Does the spiral wrap around outside work better for drawing resin away from the main vac line better than double infusion mesh? Is peel ply necessary wrapped round the spiral?

Ideally id like to work this with one vac inlet and one resin feed line.

 

I know there has been a lot of good feedback regarding MTI hose but its not really cost effective to put £25 worth of hose around perimeter on this job!

Plus its good to learn the core fundamentals and if there is a real tricky part to infuse then id get the MTI hose

 

Any feedback or ideas welcome, maybe a method with vac and resin feeds at the far ends better??

Cheers

Brett

 

 

I am not an expert as I have only done one CF project so far.
The neck of my harp is about 1.8m long and down to about 50mm wide in places. I infused this by putting a double layer of infusion mesh across the middle (The bit that is top left in the first picture of the link.) with spiral wrap resin feed over this. I had vacuum lines at both ends so that I could clamp them off individually when the resin got there.
I know everyone says that you should infuse across the shortest direction but infusing this from the middle out worked for me.

http://www.talkcomposites.com/8522/Harp

Brian.

What about this set up instead? Please look at fig c.

Main queries are:

How far shall i run resin feed down the part? Halfway likeshown, more, or less?

Spiral wrap on flange for even vacuum as shown? Wrap in peelply?

Mesh the entire part, not needed on flange right as i don’t wantresin being sucked into the vaccum spiral around periphery, possibly the vacline,

so a gap between mesh and spiral wrap vaccuum  is good??

Best set up for the job????

Thanks Brian! Harp looks amazing

i cant view the pictures on this computer, but one option if your ever unsure of how something will infuse is to test it with inexpensive materials like woven glass and polyester resin

I have made a picture like yours in case my description did not make sense.



I used a medium speed catalyst. It only took about 10 or 15 mins to pull the resin this far.
On your piece I would put 200mm of spiral vertically across the middle for the feed and 2 200mm to vacuum off of each end.

Thank you for the compliment about the harp. I am very pleased. It sounds great as well.

Brian.

You can limit your vac outlets to a minimum as the resin will flow in all directions from your inlet at approximately the same rate as long as you have a full vacuum applied for a decent length of time so if you put the inlet in the middle about 1/3rd along and the outlet on the other side, 2/3rds away from the inlet, it should infuse relatively evenly. If you're not using MTI then put a brake (or dam) in the infusion mesh just before the outlet using just peelply and this should slow it down enough.

As mentioned already, try it with a cheaper material first (glass) to see how it goes then do it again with carbon

Thanks guys, appreciate the input.

 

I will run the next one with budget materials, like most weonly learn by doing and seeing how materials behave. 

But be nice to limit thestuff that goes in the bin!

 

Brian, is Figure D like how you described?  Do i needspiral wrap around perimeter like shown to ensure a good even vacuum?

 

Chris. Is Figure E like how you described?  Only query is about the resin feed. Do i needSpiralwrap to help deliver to the left/right or will the resin find its wayjust through the inlet?

 

General query to all. I suppose the resin break with peelply before the vac outlet is generally good practice as you may need to stemthe flow where sometimes the rest of the part has not infused? If the resin starts creeping up the vacinlet before the whole part is infused we have big problems?! 

 

Last query. With the resin feed in centre/or third way alongis spiralwrap all around perimeter like i illustrated the right thing to do foreven vaccum?

Does it need wrapping in peel ply?

 

Im looking to try another infusion tonight.

Cheers 

"Brian, is Figure D like how you described?  Do I need spiral wrap around perimeter like shown to ensure a good even vacuum?"

No. I just used spiral where I have marked. About 200mm across the corner and 100mm at each end. The infusion mesh and fabric will make the vacuum equal.

Brian.