HobbyKing.com New Products Flash Sale
View Poll Results: If you are reading this thread are you an IOM owner
Yes 26 49.06%
No 27 50.94%
Voters: 53. You may not vote on this poll

Reply
Thread Tools
Old Dec 01, 2012, 05:49 PM
Registered User
jims123's Avatar
USA, CA, San Diego 92120
Joined Oct 2007
3,088 Posts
Quote:
Originally Posted by The Tug View Post
Mix up some of the west system snot(thickish) and use as a filler it gets very hard sand it back to shape and paint it. Did you put the air pump back or are the fish dead??? Do not sand down the bulb you don't want to remove lead fill it and fair it.....
Ok Will do, based on my last experience with West System packets.. I will wind up wasting a lot in the packet pair, and will want to pre- mix it slightly hotter since it took a long time to gel the last time ( about 15 minutes) ...I plan to simply pre-mix all the hardener in a packet with 90 % of the epoxy in the same packet for 30 seconds then toss 2/3rds of it BEFORE mixing in the microballs cause it takes a lot of microballs to make it thicken up.. then I'll put on a really thick blob on the bulb and let it dry hard before shaping it..

What type of paint is recommended on a keel bulb? I assume any glossy black Enamel will last pretty well after priming it? If I wind up over weight .. should I plan to drill out some lead from inside the 1/2 inch circular mounting screw area to get back in spec?

BTW.. the goldfish was already dead.. so he didn't miss the air-pump.. that bubble blow thru the Drain Plug technique worked perfect for finding leaks around the pot for the RC gear.. I tested every where else and could not find anything else leaking except there. but did have to re-do the whole thing since I wanted to get ALL the Elmers glue out, and had left a little residual on the threads of the cap and at the base so I did not seal tight.. until I pulled it ALL out stripped All the old silicon and dried glue out, and and redid it all again with silicone sealer and wiped the base clean so the lid seals 100% tight again too.. I'm looking for some stiff 1/32 inch rubber gasket material to replace the stock cardboard seal in the lid too.
JimS
jims123 is offline Find More Posts by jims123
Last edited by jims123; Dec 01, 2012 at 06:05 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Dec 01, 2012, 07:36 PM
Registered User
United States, MI, Bloomfield Hills
Joined Feb 2010
579 Posts
West System doesn't like to be mixed incorrectly, it messes up the chemical reaction. If you want it thicker so it doesn't run just add more of whatever you are using to thicken the epoxy, silica would be best and won't run.
TedFlack is online now Find More Posts by TedFlack
Reply With Quote
Old Dec 01, 2012, 08:04 PM
Registered User
Barbados
Joined Jan 2011
2,109 Posts
5-1
The Tug is offline Find More Posts by The Tug
Reply With Quote
Old Dec 01, 2012, 08:47 PM
Registered User
hiljoball's Avatar
Canada, BC, Lake Cowichan
Joined Jul 2011
522 Posts
HI Jim,

What Ted said! Epoxy is quite different from polyester. In epoxy, you need the exact quantities of epoxy and hardener for all the molecules to connect, otherwise you have surplus of one or the other weakening the result.

John
hiljoball is offline Find More Posts by hiljoball
Reply With Quote
Old Dec 01, 2012, 09:01 PM
Registered User
jims123's Avatar
USA, CA, San Diego 92120
Joined Oct 2007
3,088 Posts
Ok 5 to 1

Alright.. But why is it taking twice as long as it should to gel? It's not that cold here? I'll do it 5 to 1 again but wonder why it took 20 mins to thicken last time?
jims123 is offline Find More Posts by jims123
Reply With Quote
Old Dec 01, 2012, 09:44 PM
Registered User
Dick L.'s Avatar
Minnesota, USA
Joined Aug 2002
2,322 Posts
First - what products are you using? Assume resin is #105 - but what is your hardener? #205 [fast] should begin to gel in 10-15 minutes - depending on temp/humidity and #206 [slow] will begin to gel in about 20-25 minutes - but again depending on temp/humidity.

You use the terms thicken and gel - and not sure what stage the cure is in when you describe the status of the epoxy mix? "Thicken" usually means enough microballoons, silica, talc, etc. have been added to a "neat" mix of epoxy. "Neat" meaning resin and hardener only - nothing else. Gel usually refers to the mixture as it starts to "go off" or cure - and using a popscycle stick as example, if you can't level it out, or it sticks like chewing gum, then the product has started to cure.

Fast hardener will usually take a minimum of 4 hours to get hard enough unless it has been modified by heat or cold. Slow hardener - I usually leave overnight for a cure that can be handled. Epoxy continues to cure for weeks - so that is why many builders leave their hulls in the mold - or build a support to keep glass from twisting.

As noted by many - myself included - it is a 5:1 ratio mix resin to hardener. You can be off by a little - but your described "eyeball" method will end in frustration. The epoxy will cure too hard and possible crack - or it won't cure at all. Please review the posted diagram for mixing small quantities and read about the "concept" behind mixing WEST System Epoxy. You mix the epoxy first, then add and stir in whatever you are using to thicken the mix - AFTER a complete mix. Again - using the diagram I posted, you can vary the amount to just what you need - and not mix an entire packet. Usually those packets are made for repairs to "big" boats, and they aren't sized for the small amounts we use for the r/c sized boats. Simply reduce the size of the two circles. It is easier and costs less if you make up 3 or 4 batches, rather than dumping an entire package and dumping a majority as waste.

If really in doubt, the Gougeon's provide valuable technical service and have a lot of reference material on their site. The tech guys there are always willing and eager to answer questions or give advice.

Dick
Dick L. is offline Find More Posts by Dick L.
Reply With Quote
Old Dec 01, 2012, 09:46 PM
Registered User
United States, MI, Bloomfield Hills
Joined Feb 2010
579 Posts
It's epoxy, it takes that long to gel and much longer to harden. Probably 24 hours to fully harden and be ready to sand. West may be a little more than you need to fill a cavity on a bulb but it is the best.

Go to Sailing Anarchy Forums, Fix it Anarchy, and read all about epoxy on a thread that is going on there...good conversation.

http://forums.sailinganarchy.com/index.php?showforum=56
TedFlack is online now Find More Posts by TedFlack
Reply With Quote
Old Dec 01, 2012, 10:35 PM
Registered User
USA, LA, Mandeville
Joined Feb 2005
886 Posts
I bought a small scale, 0-100 grams in tenths of a gram, just for mixing small amounts of epoxy. I hated wasting so much when using the pumps to do small jobs.

I never use the term "gel" with epoxy resins. Epoxy slowly hardens and gets thicker and thicker, where polyester resin "kicks off" and gels within seconds. Even with the West fast hardener, I would not plan on it being hard enough to sand before 8 hours. I hate trying to sand rubbery resin.
hew565 is offline Find More Posts by hew565
Reply With Quote
Old Dec 02, 2012, 12:02 AM
Registered User
United States, CA, Fairfax
Joined Apr 2011
78 Posts
For quick jobs in filling or bonding try using the West Systems G/5 Adhesive:
An easy to use, 2-part resin/hardener system for quick repairs, tooling and general bonding. May be used in spot applications to hold parts in position while standard epoxy bonds cure. Bonds to wood, fiberglass and metal. One-to-one mixture, no pumps are required. Cures in 3-5 minutes.
Houdini13 is offline Find More Posts by Houdini13
Reply With Quote
Old Dec 02, 2012, 06:11 AM
Registered User
Barbados
Joined Jan 2011
2,109 Posts
Ohhhhhhhhh Jim you never listen do ya,first you killed the fish and now you're looking to get the snot sticky and gummy forever.5-1 and wait for the thing to harden.
The Tug is offline Find More Posts by The Tug
Reply With Quote
Old Dec 02, 2012, 10:22 AM
Registered User
Dick L.'s Avatar
Minnesota, USA
Joined Aug 2002
2,322 Posts
Dick L. is offline Find More Posts by Dick L.
Reply With Quote
Old Dec 02, 2012, 11:46 AM
Registered User
Canada, BC, Campbell River
Joined Oct 2012
57 Posts
Quote:
Originally Posted by hew565 View Post
I bought a small scale, 0-100 grams in tenths of a gram, just for mixing small amounts of epoxy. I hated wasting so much when using the pumps to do small jobs.

I never use the term "gel" with epoxy resins. Epoxy slowly hardens and gets thicker and thicker, where polyester resin "kicks off" and gels within seconds. Even with the West fast hardener, I would not plan on it being hard enough to sand before 8 hours. I hate trying to sand rubbery resin.
I went down to the vet's office and bought a couple of 12cc syringes. I dedicated one for hardener and one for resin. I made a litle stand for them and now I can make as little as 6 cc of epoxy reasonably accuratley. I have been useing the same syringes for a couple of years. Every so often I clean the resin one with laquer thinner and the hardener one with soap and water. It's worked well for me. I think I could probably mix 3cc with success but I'm not that cheap.
Don
Don Case is offline Find More Posts by Don Case
Reply With Quote
Old Dec 02, 2012, 05:33 PM
Registered User
Portland Intl, Oregon, United States
Joined Aug 2004
129 Posts
I have syringes also that I use to apply the MIXED resin/filler media. Also have the scale that West System sells. But for small batches the method I most prefur is the "drop" method. I have several squeeze bottles (aprox 10oz) with identical size holes in the nozles, this is so the drops are identicle size. Bottles are labeled with the contents (resin, slow, medium, fast, ect). If you want a very small batch - 5 drops to 25 drops (1 : 5). Just dont squeeze very fast
or you cant count the drops. AFTER mixxing of the resin/hardener add the filler (silica, microballoons) to get the consistancy you want PRIOR to epoxy setting up. If useing a syringe to apply make sure it is well mixed and the hole in the syringe is big enough to dispense.

Chris B.
old dodger is offline Find More Posts by old dodger
Reply With Quote
Old Dec 02, 2012, 11:03 PM
Registered User
jims123's Avatar
USA, CA, San Diego 92120
Joined Oct 2007
3,088 Posts
Struck a nerve?

I should have known this topic of Epoxy/ Hardener Resin and techniques would be one that's close to many of you IOM pros and builders here.. Wow what a set of great insights and tips. I do like many of your ideas and appreciate them all and will try to do it right.. if not, the second or third times usually a charm..

I was distracted this weekend with a dozen other pri-projects but I should be able to give fixing my keel a go in the next couple days .. these are all BEFORE shots.. with a temp patch and little silicone sealer on the chip in the nose..

Who can recommend a primer and paint?.. or is there a black color I can get and pre-mix it into the West System Epoxy I have that is reasonably priced?.. I think the biggest challenge will be getting it sanded shaped properly .. after it dries a day or two with a big blob on the tip that's currently chipped.
jims123 is offline Find More Posts by jims123
Reply With Quote
Old Dec 02, 2012, 11:34 PM
Registered User
8387mike's Avatar
Perth Western Australia
Joined Jul 2009
1,109 Posts
I use cheap etch primer and gloss black spray cans from a hardware store, so far I have painted about 7 bulbs.
8387mike is offline Find More Posts by 8387mike
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion X-3D Brushless Quadrocopter, general quadrocopter, x-ufo discussion tend2it Multirotor Talk 2529 Apr 26, 2008 08:45 PM
Discussion Kong Power Packs Info And General Discussion nitroshark Batteries and Chargers 10 Jan 13, 2008 12:33 AM
Discussion Kong Power Packs Info And General Discussion nitroshark Batteries and Chargers 32 Jan 03, 2008 04:02 PM
Discussion General Discussion PLD Australia 172 Nov 27, 2006 11:26 PM
General Discussion / Training Area zax Site Chat 0 Oct 03, 2001 02:48 PM