Mixing Ve resin.

[Tungsten]

I've picked up some Ve resin to try out,Derakane 411-350.Supplier told me 5 drops of catalyst per fl/oz(29.5ml). a search on the net has a range from 5 to 13 drops per oz.
I'm experimenting with infusion so an open time of 30-40 minutes would be good,shop temp at 60F.

Drops work well for some of my tests as I'm mixing only 2 oz batches at a time.

What say you?

 

[gonzo]

It depends on the formulation, but usually it takes about 1.2 to 1.8% hardener.

 

[Tungsten]

Well did some tests,5 drops did nothing to an ounce of resin.24hrs and still runny.13 drops seamed just right, 45 min open time it took about 5 minutes for the foaming to settle down after mixing.

 

[groper]

You can use different catalysts to get rid of the foaming... The Norox 50 catalyst is what I used for this reason...

 

[Tungsten]

Thanks I'll look for it,i wasn't aware of the foaming so I thought this was a bust but after 5 min it degased and ended up very clear.

 

[Herman]

Peroxides containing H2O2 give a foaming effect. Ask your supplier for a suitable peroxide.

Also, counting drops for me is not the way to go. Invest in a decent scale. Can be an old or pre owned one, but make sure it has a fine scale.

 

[Tungsten]

Well I have a triple beam scale,never thought it would be sensitive enough to decipher drops.Ill have to give it a try.

 

[ondarvr]

2 oz batch sizes are very difficult to catalyze accurately, you need a rather sensitive digital scale for acceptable accuracy. In the lab we use 100 gram batches for QC purposes, this amount can more easily be measured for better consistency. In the field I use 100cc calibrated cups and pipettes (looks like an eyedropper and marked with CC's)

United Initiators sells 925H, it works well in VE resin, and gel coat too.

 

[ondarvr]

This resin has a rather high viscosity for infusion, but will work for small projects.

Are you adding the promoters, or did your supplier? The gel times of VE's tend to drift rather quickly, so depending on when the promoters were added your gel times may vary from what you think it may be. If you are adding the promoters, then the data sheet will get you in the right range.


http://www.ashland.com/Ashland/Static/Documents/APM/Derakane 411 350 tds.pdf

 

[Tungsten]

Yes my supplier added the promoter,and yes gel times are difficult to get consistent.

If I add a little heat to the resin it thins down nicely,looking at some charts in the 80-90F range its showing 1% in some cases.I understood not to go below 1%.

I am getting good results infusing thick laminates but I'm only getting a travel distance of 12" before it kicks at around 30- 45 minutes.

 

[ondarvr]

This is a generic estimate, every resin will be slightly different. The resin is tested at 77F, and about every 15 degrees above that will cut the gel time in half, 15 lower and it will about double it.

So heating will lower the visc, but shorten the time allowed to fill it. A trade off. If more time is needed add the inhibitor or use a blended catalyst.

Use the data sheet I linked to make the adjustments if needed.

A resin with a lower starting visc is desired for infusion.

 

[Tungsten]

Thanks for the link,its all blurry to me as I don't understand what it all means.I'll have to go back and talk with my supplier and see what is needed to extend gel time.Which by the sounds of it is possible.

 

[groper]

The resin can be retarded with some inhibitor. However, flowing 12" in 30-45mins is very slow, you should find a faster flow media first and try that.