West System - Gel state, how soon for laminating

[MercMark]

West system says that the epoxy will reach a "green state" or Gel state after pot life but before final cure. It says that you can reapply once it's in this state and it will chemically bond with the first coat. The longer into the gel state the less effective the chemical bond will be. <br /><br />They provide a graph of the cure times, but the graph has no units on it.<br /><br />If I'm using 5:1 fast, i think they call it the 105 hardener:<br />-when does the gel state start?<br />after the 20 min pot life?<br />after one or two hours?<br /><br />They describe the gel state as being like hard rubber. No longer tacky but you could dent it with your fingernail.

 

[MercMark]

Re: West System - Gel state, how soon for laminating

.

 

[MercMark]

Re: West System - Gel state, how soon for laminating

^^

 

[Pun]

Re: West System - Gel state, how soon for laminating

I'm no expert, but I think it's really going to depend on temperature and humidity in your workplace. I know that in my 70 degree shop that's fairly humid, it took about 10-12 hours to reach gel state. There are so many variables. Thickness of the resin, temp, humidity, accuracy of mix ratio, how well the product was mixed, etc. <br /><br />I think the fingernail test would be a good indicator and there is no rule on how long it's gonna take.

 

[MercMark]

Re: West System - Gel state, how soon for laminating

10-12 hours? you must have been using a slow hardener.<br /><br />West system claims solid state in 6-8 hours, which is the state after gel state according to their graph.

 

[BillP]

Re: West System - Gel state, how soon for laminating

Like pun says...it depends on temp and humidity and whether it is in the pot or spread out on the glass. WEST probably has a temp that goes with your graph (many mfgs use 70F). Do the finger nail test and keep notes on temp, humidity and time. That will give benchmark for working times on future glassing. Remember, lower temps and higher humidity lengthen kick times. Hotter and drier is opposite.

 

[MercMark]

Re: West System - Gel state, how soon for laminating

It can't vary signicantly by more than a couple of hours if the full cure time is 6-8 hours, can it?<br /><br />If they can give me a full cure time within a two hour range, why not a gel state time?<br /><br />I've emailed West System. <br /><br />Can anyone share experience?

 

[Bondo]

Re: West System - Gel state, how soon for laminating

I'd Think it's Pretty Well Explained Right Here.............<br /><br />It works Exactly like Bill,+ Pun have stated........<br /><br />A "Pot" Will Kick Off in Minutes Sometimes.......<br /><br />A "Painted" Surface will take Forever to Kick Off, Because it's Spread So Thin.......Especially on a Cold Day.....<br /><br />Just Go Buy a Gallon,+ Start Playing,......... You'll Figure It Out,..........<br />If it's a Really Hot Day,... Set your "Pot" in Ice,... It Won't Kick Off so Quick........

 

[MercMark]

Re: West System - Gel state, how soon for laminating

hm. being absolutly uncertain as to how long it will take to reach the gel state is a difficult thing to cope with.<br /><br />Makes me want to use Polyester.

 

[BillP]

Re: West System - Gel state, how soon for laminating

Originally posted by MercMark:<br /> <br />Can anyone share experience?

The epoxy I've been using lately (not west) halves the kick time for every 10 degree increase over 70F. Reverse for under 70F. That's why it is critical to take notes and establish accurate working times...epoxy or polyester. The good thing about polyester is you can add or subtract hardner to change kick times.