pin hole nightmare

[GiantScale]

Iv been working hard to get a epoxy rigger ready to race, & am close with all holes drilled & everything straight & ready to put together fast. But after sanding for three days Iv uncovered pin holes which go clear through the hull & sponsons Id have to guess at least 200 holes. 1/2 of them go through.

Getting epoxy into the holes requires unthickened epoxy. But it usually seeps out of the hole overnight. Then waiting 24 hrs to cure. Washing-sanding-washing all over again. This is getting old and I only have one eye not swollen shut to continue



Any suggestions to speed this up?

Thanks

Mike

 

[Ron Olson]

How about trying Bondo or spot putty? A lot faster and it doesn't leak through.

 

[GiantScale]

Thanks Ron.

I was not sure if I wanted to trust the water tight integrity of the hull to body filler. Iv got some good automotive evercoat polyester putty & fiberfilled everglass I was going to fill the small dents with. It sure would speed things up.

Hmm

Mike

 

[GiantScale]

The putty I have is only workable for 3 min. Then it starts to flash & wont spread. Iv mixed 12 times and am not even 1/2 way done. I have allot of high spots now but to tacky to sand after the 20 minutes stated.

How do I make the working time longer or thin it?

Mike

 

[Crank2max]

I've thinned polyester resins with acetone to flow it into tight places - definitely slows it way down also ... the acetone will evaporate after time - do this in a well ventilated location!

 

[GiantScale]

UNCLE!

 

[MikeP]

I have done it with CA before, I sprayed CA kicker on first then dab the holes with a toothpick. Don't sand any more on the hull it brings up more holes. Only sand what you spread on.

-MikeP

 

[[email protected]]

I hate to suggest this a make more work for you but in my experience I find it very valuable to actually open up some of the small pinholes by taking a small drill and enlarging the hole. What this does is provide more "BITE" for the bondo to stick to. Bondo is sometimes a nightmare and later on after you painted the vibration can pop it free leaving ugly holes.

I hope your not working on a Prather Spitfire. They are by far the worst Pinhole offenders!

 

[GiantScale]

I fear I may have just ruined my rigger by using poly based filler. It wont dry after 24 hrs & says sandable in 20 minutes. ???

& solvents to remove it on epoxy is a bad idea.

WOW. Now that was a expensive learning process.

hind sight's 20/20

 

[rcboatlover]

Try giving the filler alittle longer to cure. Put it in a warm place and shine some lights on it to heat it up. Becarefull not to warp the hull. I have had the same problem with the polyester resins. Even after the heat the surface was tacky. I had to set is aside for a day and let it harden. Don't junk it out yet!

 

[missbudpilot55]

Hey guy's you are all on the wrong track, let me first say the polyester's and epoxy's don't work together. To fill the pin holes in an epoxy resin and fiberglass boat hull you have to use a very thin mixture of West Systems Epoxy and cavasil or micro balloons. You can thin the mixture with lacquer thinner so that it can be brushed on.

Only mix enough to do approximately a 6" x 6" area at a time, take your time it isn't something that can be done in a hurry. By working on a small area at a time you can see the results. Expoxy glass boats are lighter but the time required to prep them for the first coat of primer is a long and slow process.

The first steps are to clean ther hull with a lacquer thinner to remove any of the release agent that may still be present, after doing this then inspect the hull and mark any obvious holes with a sharpie felt tip marker. Using the epoxy/filler mixture work on a 6 x 6 area at a time and that way you will know that this area is complete and satisfactory for primer when the boat is ready for that stage. Patience is a virtue!!!!!!!!!!

It may take me upwards of 4-6 months to prep a new1/8th scale expoxy glass hydro for just being ready ffor primer.

 

[[email protected]]

Man 4-6 months just for primer! That's some serious commitment. You must get some really impatient customers?? I'd love to see some pictures of your boats. Can you post any pictures??

 

[missbudpilot55]

This a picture of my 1994 Bud, 8 months to complete from a kit. I do not build boats for other people anymore, only for myself. I have a 79 Budweiser I bought in 1990, it was a very bad molded hull as har as pin holes and voids, it took me 10 years of aguish and disgust to complete, almost gave up, I'll post a pic of it later.

 

[[email protected]]

AAAAHHHHH, where's the attachment??

 

[missbudpilot55]

Can't get the attachment to work, will try something else this evening.

 

[missbudpilot55]

94 Bud

 

[ClayGlover]

whew! someday....someday....

i've got 2 sets of Newton prints already for the '94 smokin joe. i'm placing the order with thunderboat reproductions for a f/g cockpit, cowl, and stack. man, thanks for the inspiration!. i needed a good kick in the motivational rear-end, and that miss bud picture did the trick ;D

nice boat!

 

[missbudpilot55]

Miss Bud is in drydock as driver error gave her a real bad bobo, crushed the left sponson when I hit the launching dock at about 35 mph, wasn't quick enough on the trigger, she will completely re-done in about another 2 months. Got to finish my new shop off first. 8)

 

[offshoremodels]

guys Bob violet makes a pin hole filler, great stuff same thing they use on there jets. I have used it and primed the next day.

 

[offshoremodels]

http://www.bvmjets.com/

Pin Hole Filler, Part #1925, $6.75

Pin Hole Filler

Pin Hole Filler

Fiberglass preparation

Wipe it on a fiberglass fuselage or resin finished wing surface before primer, allow to dry to a haze, then wipe it off. When you spray on the first coat of primer, most of the fine pin size holes have been filled reducing your finishing efforts.

http://www.bvmjets.com/Tools/pinholefiller.jpg