What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

A few things

J

JohnF

Well Known Member
1. West System Epoxy kit from Aircraft Spruce with 'slow' activator won't harden. One pump from West's "Mini Pumps" of resin and one pump of activator, stirred for a minute or so...three days and things are just sticky, and not hardening. West sending replacements, want resin/activator back to check what's wrong. I have a real mess of resin that won't harden, yet is just gooey and sticky enough to be difficult to remove.

2. Hose from left side of oil cooler touches top of muffler and can't really be raised much...not certain what to do here. I doubt fire sleeve should bear against the muffler...thinking about trying to wrap it with Fiberfrax but don't like that either.
 
Point 2

Re: Point 2, mine is the same. I plan to shorten the bracket holding it, but I'm not convinced that's good enough.

Cheers...Keith
 
Also Re Point 2

I had the same problem. I loosened up the nut on the exhaust pipe and rotated the braket outboard (sliding the clamp over the line a little outboard also) so that it was at an angle pointing outboard rather then straigh up and down, then retightnened the nut. That created a gap of about 3/8" between the oil line and exhuast tube. After 30 hours of flight there are no signs of trouble or excess heat in the oil line.
 
Confused!

Which hose are we talking about? Is this the left hose as in my left while sitting in the cockpit facing forward? Furthermore is this the hose coming from the external oil tank from behind the engine to the oil cooler? Do you guys know how to tie wrap and make stand offs?

John
RV12 N1212K
 
confused

Yes, I know how to make stand offs, and to use tie wraps. There is no room for a standoff, and there is nothing to tie to.... your turn
 
a few things

Photo tomorrow .. will be trying to remove the sticky/pasty West Resin that won't harden from the cooling tunnel...not fun.
 
Make a test batch with new epoxy

to see how it performs. Also the pumps are not as accurate as a digital gram scale. I use the pumps just to dispense into cups then weigh them to get the correct ratio.
 
Mine worked perfectly

Did you "prime" both pumps before shooting the measured amounts? Mine set up faster than I really wanted in 85 deg temps.

Wayne 120241
 
A Few Things

John -

Regarding the epoxy problem... I'd recommend you throw the pumps in the trash and use a scale to measure your epoxy. People I know well and who's opinions I respect have suggested that the ratio/mix tolerances are so wide that it's difficult to mess up a batch of West epoxy, but my experience has been different. I've had several instances of the West epoxy failing to cure, but not since I switched to a digital scale. My pumps leaked down, and the first stroke after some small period of sitting around was never a full measure. You'll find that you waste a lot less epoxy with the scale, too - you can mix what you need rather than multiples of full pump-strokes.

I paid less than $20 at the local pawn/gold panning supply shop for a small digital pocket scale with 0.01 gram resolution. If you're building up fairings, you'll probably make many 60- & 90-gram batches (I don't work fast enough to get the good out of bigger batches). But there will be times when you just need a dab - like your kid's broken toy that warrants something better than Elmer's, or a dime-size low spot that needs one or two plies of patch to bring it up closer to level with the surrounding areas. I don't often mix batches smaller than 18 grams, but the high resolution helps prevent overshooting the target weight.
 
Concur with n8zg, good advice about the scale. Also have a calculator handy, of course.

And don't forget to zero the scale once the cup is on it.

I've gotten decent digital kitchen scales with .1 or 1.0 gram resolution at Bed, Bath and Beyond, and they frequently run 20% off coupons.
 
Non curing epoxy...

West Systems sells, recommends, and supports the ratio pumps. I don't see how you can go wrong using them; and they are very convienient.

One thing that comes to mind regarding the epoxy not hardening is the type of cups used. It is possible that some cups have wax or something on them that could contaminate the mix. Just a thought.

Tony
 
tomcostanza said:
What "by weight" ratio do you use?
Click to expand...

West is 5 to 1.

No pumps for me. I don't even use them to refill the cheap squirt bottles used to dispense resin and hardener into the cup.

Go ahead, try to mix an accurate 12 gram batch of West with a pump. Then mix some T-88 or Hysol.....

A scale ratios any epoxy perfectly, including those too viscous to pump.
 
I used to use scales...now I just pump

Tony_T said:
West Systems sells, recommends, and supports the ratio pumps. I don't see how you can go wrong using them; and they are very convienient.
Click to expand...

I attended an RV Fiberglass forum given by Sam James at Oshkosh. He also endorses and wholeheartedly recommends the pumps. Yes, you have to be sure they are primed. But after that, they are really simple to use without making mistakes.

I used to always use scales when mixing epoxy untill I tried the West Systems pumps, and I see no need to go back to scales. Scales are accurate, of course, but there are so many ways to make mental mistakes that nullify that accuracy.
 
Both methods are good if executed properly.
I used both and I prefer Scales as I know it is exact
Some Like Fords and some like GMC.

If you aren’t sure of your Ability use both

Joe Dallas
www.joesrv12.com
 
Last edited:
point 1...

I had the exact same problem....I then realized I had the wrong pumps in the wrong containers... I switched the pumps correctly....perfect now.
 
tomcostanza said:
What "by weight" ratio do you use?
Click to expand...

The weight and the volume ratios are given on the containers. They vary with the particular hardener.

With the pumps, you need to ensure that they are working properly. Often the first stroke is a partial load. Hate to say this but sometimes it's worth wasting a couple of small paper cups, one for the resin and one for the hardener. Put the first stroke or two in the cups and when you're sure that the pumps are working right, use your mixing container. Then pour the other two containers back in their respective cans - little waste except for the cups.
 
Pump and or scales

David Paule said:
The weight and the volume ratios are given on the containers. They vary with the particular hardener.

With the pumps, you need to ensure that they are working properly. Often the first stroke is a partial load. Hate to say this but sometimes it's worth wasting a couple of small paper cups, one for the resin and one for the hardener. Put the first stroke or two in the cups and when you're sure that the pumps are working right, use your mixing container. Then pour the other two containers back in their respective cans - little waste except for the cups.
Click to expand...

Why not use the pump in one cup then weight it and if it's the sum of the weights it good to go.
The main drawback is the batch size.

Record the results to see how accurate the pumps are or aren’t.
Joe Dallas
www.joesrv12.com
 
Last edited:
West System Epoxy Follow Up

West replaced the epoxy and activator when the product refused to harden; and provided a replacement set of their mini-pumps. They paid for shipping to me, and shipping to return the stuff that would not set up after days.

Today they called me and said the epoxy and activator that I had returned was OK, but the paper cup I sent them with some of the epoxy that would not harden was analyzed by their chemist and they determined that excessive hardener was added to the epoxy. I cannot determine how that happened since I have used West's epoxy before, and also since the incident and never had any problem. I can only guess, and its a wild guess, that somehow the mini-pump malfunctioned.

I am very pleased how West responded to my complaint, and how they followed up after determining what happened. A good customer relation act.
 
You must log in or register to reply here.
Back
Top