Geek factor of 10 & Jeffco/Strake update

[CBarber]

Ok, I admit it, when it comes to Trek, my geek level goes straight to 10 AND when you are kinda putting off the inevitable, in this case to start removing the Jeffco from my inner stake skins, you come up with all sort of silly things to distract you. Yesterday I straightened up the hangar and today I started to look way down the road and add my Trek touches to my Velocity.

 

Submitted for your consideration.

 

Also, here are some photos of me sanding/grinding etc to remove the naughty Jeffco from my stake inner walls. You will note that I choose to cut out the inner skins in a couple of the compartment and in others, generally where I had more working room I ground out most of the Jeffco. This is still a work in progress as there is still quite a bit of residual Jeffco to remove. Also, this is NOT an exact process and I have hit blue foam a few times.

 

I have spoken extensivily with Velocity, Inc and they are ok with my plan to lay down new glass over the cut out sections and say it is ok to lay new glass over the ground down areas kinda making a inner bladder. The new glass should adhear to the sanded older glass.

 

Where Jeffco failed, which was most prevelant on the top right strake near the front all this upper glass has been removed.

 

I used a Dremel with a RotorZip cutting bit to remove the inner glass. This alowed me to cut a very precise line in very restrictive areas.

 

Flame suit on...

 

All the best,

 

Chris

[CBarber]

Remember, these pix are not for those who get queeeeeeezy.

[CBarber]

and finally, for today......

[Edge 513]

It is killing me to see you doing this to your finished work...

[TMann]

Hey Chris!

As one of my Nebraska neighbors would say ....... "Git'er done!"

You have a great attitude! Don't look back, and keep looking forward!

T

[Monty Roberts]

Captains Log for NCC-17010

 

Took heavy damage from an encounter with a Clingon bird of prey. Lost most of the outer skin panels....will attempt refit on orbit.......If I can get these green alien chicks to leave me alone.

 

Sorry I couldn't resist.

 

Chris you have certainly had your share of setbacks...you are showing remarkable resilience and dedication.

 

NEVER give up!!

 

Monty

[Wayne Hicks]

Have you tried sandblasting or soda blasting to remove the Jeffco?

[CBarber]

Yes, I have tried blasting against the Jeffco and it was ineffective. The grinding/sanding is much quicker and more manigiable. The aluminum oxide barely made a dent after direct exposure to the blast stream. Now, that being said, I will blast the glass after the grinding off the Jeffco to prep the surface and hopefully get any minor amounts of Jeffco left in the weave before I lay new glass.

 

My new EZPoxy, Bid and Jeffco arrived a couple of days ago....$604.00 later:sad:

 

Monty, THANKS, I needed the laugh and a fix to my Trek addiction.

 

Hailing frequencies open.....

 

All the best,

 

Chris

[Cozy Girrrl]

Wow, that not for the light hearted, I'd have grabbd my teddy bear and had a good long cry, maybe about six months worth then taken up a new hobby, something less painful like base jumping in a small town.

...Chrissi

[Lynn Erickson]

Yes, I have tried blasting against the Jeffco and it was ineffective. The grinding/sanding is much quicker and more manigiable. The aluminum oxide barely made a dent after direct exposure to the blast stream. Now, that being said, I will blast the glass after the grinding off the Jeffco to prep the surface and hopefully get any minor amounts of Jeffco left in the weave before I lay new glass.

 

My new EZPoxy, Bid and Jeffco arrived a couple of days ago....$604.00 later:sad:

 

Monty, THANKS, I needed the laugh and a fix to my Trek addiction.

 

Hailing frequencies open.....

 

All the best,

 

Chris

I don't want to add any more grief to to your situation but why go back to the Jeffco coating. if you are going to do a layup on the entire tank why not just use a wet layup of a structural resin or a geffco laminating resin that is compatible with the fuel that you are planing to use. any time you add a coating over cured resin there is a chance of peeling. in the long ez/ cozy type constrution the inside of the tank is a 2 ply layup that is left a bit wet and that is it. some have added a third ply of very close weave light cloth to help hold the resin in place until cure. some have used cabosil in the resin to thinken it and elininate pin holes.

[Lynn Erickson]

Wow, that not for the light hearted, I'd have grabbd my teddy bear and had a good long cry, maybe about six months worth then taken up a new hobby, something less painful like base jumping in a small town.

...Chrissi

Chrissi, I am not using auto fuel and I have not done any research on the compatible resins. Has it been determined what resins are good and which ones not to use?

[RGlos]

How are getting at the underneath portion of these strakes?

 

I've nothing against the Jeffco but why would you need to use it again?

 

Suggestion. Test the EZ poxy on one of the stipped off pieces of glass. Sand it down well, apply the cloth and wet it down with the EZ poxy. Then apply several coats in progression.

 

If will get you prepared for the big job ahead. I used the original SaftyPoxy many years ago. It should be enough.

[CBarber]

RGlos, not sure what you mean by getting to the back side of the strakes. I have had to cut into the tops and have removed some of the inner skins to the foam. Other parts, where I have more elbow room I have ground off the Jeffco. Where the Jeffco actually fell off in mass (the top of the right strake inner third) I have removed the inner skin. I feel this will eliminate any bad glass/contamination issues that I can not determine.

 

Lynn, this is something I have wondered about. On the sections I am rebuilding, why not just lay the glass and use Jeffco instead of EZPoxy with Jeffco applied on top. My reason, so far, is the EZPoxy construction is what I know. I do not know any of the features of the Jeffco except it is the "accepted" sealer for "unusual" fuel. I originally used it more as a safegaurd to the future unknown AND that the idea of using the Deltahawk diesel was being toyed with. I figured at the time it was the safe route. I have since developed my rotary install and have been using fuel from the Shell station across from the airport wich does say it contains up to 10% ethanol.

 

This is completely unscientific, but I do not think that the fuel or the Jeffco is the culprit. I can only imagine the sufaces got contaminated somehow in my garage way back when. Who knows, maybe some dryer lent got kicked up in the air (my washer/dryer are in the garage). I do take some solace that my build helper, David Staten reminded me that he was there for my strake builds and he is certain about me not being a complete incompetant for this process.

 

Velocity, Inc stated, and this seems about as reasonable as anything else, that perhaps there were a couple of minor pin holes in the Jeffco that allowed the fuel to outgas and get BEHIND the Jeffco and between the Jeffco and underlying glass.

 

The glass on the strakes was prefab from the factory and I did NOT do anything to it other than prep sand and clean with denatured alchohol(DA). It has been mentioned that DA may contain some contaminants unique to each brand. The only other potential source I can think of is the duct tape I applied when I did my "false" bonding of the strake top to the strake (in which I then popped off, twice, to get a good fit).

 

I am concerned/frustrated that a reason is not readily apparant and here I go getting ready to do it all over again. All I can do is be a certain as I know how to be that the work is completed in as mindful a manner as I can muster. Something failed. I am not wise enough to know exactly how to determine what. I have had many folks speculate, as have I, but no clear answer has been presented. Also, in my "investigation" there seems to be a lack of consistancy. I had a major delamination in one part of the strake but only a couple of chipping type failures in other areas with another moderate flaking in the left strake. Most of these areas were done at different times, thus I fell is is unlikely I did the same mistake repeatidly.

 

Heck, while almost unavoidable here in Houston, maybe it was the humidity.....

 

Thanks for all the continued input and suggestions. If y'all have any words of wisdom as to prep for this go round, feel free to share.

 

All the best,

 

Chris

 

Full disclosure of the build including the mess ups is tribute to the fine example provided by the likes of men like John Slade. Build on.

[steve]

The glass on the strakes was prefab from the factory and I did NOT do anything to it other than prep sand and clean with denatured alchohol(DA). It has been mentioned that DA may contain some contaminants unique to each brand. The only other potential source I can think of is the duct tape I applied when I did my "false" bonding of the strake top to the strake (in which I then popped off, twice, to get a good fit).

 

that is the secant time i have read that the glass would not stick or cure.

we all mite want to see the brand of 200 mile tape we are using

i did it, but blamed my mix

[RGlos]

Sorry Chris

 

I meant the underside of the top cover on the strakes.

 

Again, I suggest that if you have a piece big enough left over, you can test it.

 

Sand it down to roughen up the surface and then apply a wet layer of jeffco impregnated cloth or EZ poxy impregnated cloth and see how it sticks or make two test strips, one of each.

 

I'm with Lynn Erickson on this. Why go back to Jeffco once you have been snake bit.

 

Nothing against Jeffco, I know nothing about it.

 

I might even make a piece up, clean it with the same alcohol, let it dry and apply another coat of jeffco over it. The idea is if the results are repeatable you probably are closer to the root cause.

 

Maybe even make up some small mini tanks with no tops and actually fill them with the same fuel and let them sit for awhile. You can make covers of plexi glass from the hardware store. 6"x6"x3" should do the trick.

[Steve Innova]

I would, at minimum, remove ALL of the original JEFFCO, not just the places where it delaminated. The entire batch is suspect.

 

Soda blasting may be more effective than sand blasting against a thick, pliable JEFFCO epoxy coating.

 

I 2nd (or 3rd) the suggestion to try out the layups emersed in gasoline and or alchohol to test adhesion. It's worth waiting several months to avoid having this problem again.

 

I never clean parts with alchohol, I always use acetone.