help with calibrating a Binks 2001 GW

I have been using this Binks 2001GW set up for about 6 months for some small hatch production (1-2 per month) but basically guessing how to properly calibrate the catylist...anyone use this and have any advice?

Thanks

Tom
pennyan@eznet.net

 

Hey TJ, how you doing? Why don't you just use a cup gun.

Joe S.

 

Hey joe,

I really like this setup...its an external mix gun so I can start and stop as much as I want and do not have to clean it out or worry about gel setting up in the head, and I can shoot a gallon at a time...more if I want to add a bigger pressure pot.

its a great system, amayzing no one else uses it!

Building anything lately?

 

Nobody uses it because there’s no way to tell how much catalyst is being dispensed. It seems like a great idea and if you could meter the catalyst and get it even close to the correct ratio it would be.

 

Thus the posted question. the binks instructions do outline a proceedure, basically spray into a cup for a particular time frame and weight, I just found more material blows all over the place then in the cup...

 

I think I have one of those sets that I haven't used in years, I don't remember the model number but it had a 1 & 1/2 gallon catalyst tank with two glass tubes on the side ( one for level the other for flow rate). It atomized catalyst into the air supply of a Binks N 16 gun which I could supply resin from either a two gallon pressure pot or a 4 to 1 gecko pump. If I remember right I had a chart for % of catalyst flow, ounces per minute of resin flow, and desired catalyst ratio.
It was easy to find my flow rate by first turning the atomizing air off, removed the air-cap ( While squirting resin / gelcoat you'll get a couple drops of catalyst from the lines), set your pump / pressure tank operating pressure, and hold your measuring cup in such a way as to not allow the catalyst drips in your measuring cup ( so you can reuse the resin)( this will be easier with the air-cap off ), always pull the trigger all the way back. Resin flow will very with the temperature of the resin, how fully you pull the trigger, or the operating pressure.
The setup is not popular because it's quite dirty ( atomized catalyst).
If this sounds like your setup, I'd be happy to dig out my manuals.

I'm sorry, a long-winded reply and then I remembered that Binks model numbers started with a gun model ( 2001 GW) so this is based on the 2001 gun not the 18 N and I think that gun had a small device that atomized catalysts on the side of the gun. You can still measure gelcoat flow as I did but I don't know how you measure your catalyst flow.

 

The two systems are different, but they do have the same issue of unsure catalyst ratios.

The injector type you just described can be sort of calibrated and was used in production for many years with OK results, but the catalyst ratio would constantly change, requiring a great deal of attention to keep it even close. Most production units now use a slave arm type metering system. The problem was there was no relationship between the gel coat and catalyst delivery systems, if any aspect of either system was adjusted you needed to recalibrate, any tip change, pressure adjustment, fan adjustment, temperature change and even climbing up on scaffolding would change the ratio.

The type the OP asked about is a normal pressure pot with a small catalyst injector near the tip. With this type of spray equipment its very common to make many adjustments to the delivery rate and fan even during the gel coat process, every one of these adjustments changes the ratio and should require recalibration.

With both types of equipment I rarely see a customer calibrate them, it may have been done at some time in the past, but so many changes have been made since that time the settings would be meaningless.

What made the use of this type of equipment possible was the very forgiving chemistry of polyesters, catalyst ratios could be off a great deal and the part would still look good as it went out the door. A few years down the road some of the issues may show up though, and they may include yellowing, chalking, fading, cracking, blistering, peeling, etc. When these problems occurred it was typically blamed on the product, not the equipment or methods used in production.

 

The only way to calibrate it is to measure what comes out of each nozzle over an exact period of time and then do the math.. Any adjustment will require new calibration.