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Mixing Instructions Chart

joedallas

joedallas

Well Known Member
First time using a tank sealant


How accurate of a scale do I need for mixing Tank sealant
and about how much should I mix for about ten inches of a 5/8" tank seam

Is there a Mixing Instructions Chart to predetermine amount needed

Joe Dallas
 
Mixing

A cheapo Harbor Fright scale will work fine. Gram function works great.
That said, if all your doing is one short section, mix up about a heaping table spoon of sealant with about twice a BB size dollop of catalyst. Result should be dark grey. Mix 2 minutes before use and make sure you scrape all the black catalyst into the mix.
Mix rate is 10:1
 
I have had my best results using a digital kitchen scale with gram readout. I measure out N grams of the black catalyst and N * 10 grams of the white sealant. So, for example, when I was mixing a batch to seal a tank leak I dropped in 3 grams of catalyst, then put in the light colored compound to 33 grams total. You don't want to guess on the mix ratio. Decent quality digital scales are cheap. Just be sure to zero it out with the empty cup on the scale, and use different tools to get the two parts out of the containers so you don't ruin the whole batch. And store the unused tank sealant in your freezer or deep freeze.
 
In a perfect world it would be great to help someone build their tank and learn all the set up needs, and the tricks about mixing.
Have MEK or acetone available in a cup and paper towels to do clean up as you go. Plenty of popsical sticks for mixing and application.
Several videos out there about mixing, application, and clean up. It's not the most enjoyable but not that bad.
 
Joe -

As mentioned the mixing rate is 10:1 ... by weight.

I have been mixing it in 20 gram batches using the inexpensive Harbor Freight desk top scale (not the small hand held).

I place small plastic disposable plates on the scale then load it with 20 grams of resin and then remove some and creep back up to 20 again ... (I do this because there is no tenths of a gram on the scale). Then add the 2 grams of the black hardener. One thing about the HF scale is it times out at 45 seconds, so you need to remember to touch the scale occasionally to prevent a timeout.

The reason I mix 20 grams is the mixed batch fits very nicely into 12 cc syringes available at livestock feed stores in the veterinary supply area. Apply with the syringe and smooth out with a Popsicle stick. Using a syringe to apply the tank sealant IS the way to go compared to using a Popsicle stick or tongue depressor exclusively ... (having done it both ways).

The syringe also makes nice beads of sealant along the instrument panel/longeron junction, ect. When finished, push any unused sealant out of the syringe and let it set up overnight. By doing so, the plunger can be pulled back out and cleaned up because the sealant won't stick to the syringe ... so the syringe can be used at least a few times. I do run a paper towel into the syringe to remove the lubricant prior to first use.

Happy Building,
 
Lay down plenty of plastic and change gloves often to keep the mess just this side of unbearable! Mine took a full week to finish curing. Lay out some test blobs so you don't have to disturb the tank to see if it's cured.

Have plenty of Popsicle stick mixers (Hobby Lobby has them) and small Dixie cups available.
 
Ohaus YJ501 Gold Scale

This is what I was concerned about
with out a finer scale and only adding 3 grams of accelerator you could be off by as much as 24% if you have 3.9 grams and you think you have only 3 grams.

I found this scale that is accurate to 0.1 grams


http://www.affordablescales.com/sho...60_Wxx23q6jISRyzO1_xQaAgLV8P8HAQ#.VniG9-RIiF5

Thanks All
Joe Dallas

John-G said:
Joe -

As mentioned the mixing rate is 10:1 ... by weight.

I have been mixing it in 20 gram batches using the inexpensive Harbor Freight desk top scale (not the small hand held).

I place small plastic disposable plates on the scale then load it with 20 grams of resin and then remove some and creep back up to 20 again ... (I do this because there is no tenths of a gram on the scale). Then add the 2 grams of the black hardener. One thing about the HF scale is it times out at 45 seconds, so you need to remember to touch the scale occasionally to prevent a timeout.

The reason I mix 20 grams is the mixed batch fits very nicely into 12 cc syringes available at livestock feed stores in the veterinary supply area. Apply with the syringe and smooth out with a Popsicle stick. Using a syringe to apply the tank sealant IS the way to go compared to using a Popsicle stick or tongue depressor exclusively ... (having done it both ways).

The syringe also makes nice beads of sealant along the instrument panel/longeron junction, ect. When finished, push any unused sealant out of the syringe and let it set up overnight. By doing so, the plunger can be pulled back out and cleaned up because the sealant won't stick to the syringe ... so the syringe can be used at least a few times. I do run a paper towel into the syringe to remove the lubricant prior to first use.

Happy Building,
Click to expand...
 
There are scales on eBay with 0.01g resolution for between $6 and $15. I agree with John-G. Use a syringe to apply an even bead without as much mess as a stick. Using more sealant than necessary is not better because the excess will ooze out both inside and outside of the tank.
 
Scale

skydiverlv said:
This one from Harbor Freight is 9.99 and measures in .1 grams
I have used the previous model for several years mixing sealant and epoxy.
I have west systems pumps but one can mix smaller amounts accurately with this scale. The user manual is available at the lower URL.

http://www.harborfreight.com/1000-gram-digital-scale-60332.html

http://manuals.harborfreight.com/manuals/60000-60999/60332.PDF
Click to expand...

Upgraded version of the one I got from Harbor Fright. Built my tanks with it.
I'm sure I'll get flamed but Proseal will kick off even if the mix is on the white side. Takes a long time but it will set. I tried samples. Towards the black side it just sets faster.
 
Scales

$10 Digital scale from harbor frt works great to mix sealant and activator by wt. It will come in handy for mixing fiberglass resin later. I keep a thin ziplock on mine to keep it clean.

Don Broussard

Rv9 Rebuild in Progress.
 
+1 on the scale.
For mixing I bought the $1 plastic cutting board sheets at the dollar store (two for a dollar). I also have one of the 3" pink plastic bondo mixing paddles from the auto store. Zero the scale with the sheet on it (half sheet for me actually). Then the sealant, then dab the catalyst on top till it weighs right. Mix like bondo with the paddle - good to go. Sticks break too easy for me.

After the board dries the proseal peels off easy. Same for the hand paddle. Reused many times. I think three hand paddles come in the bondo paddle package.
 
plastic cutting board sheets

I like this idea
This is how I will do mine

Thanks

Joe Dallas

JDA_BTR said:
+1 on the scale.
For mixing I bought the $1 plastic cutting board sheets at the dollar store (two for a dollar). I also have one of the 3" pink plastic bondo mixing paddles from the auto store. Zero the scale with the sheet on it (half sheet for me actually). Then the sealant, then dab the catalyst on top till it weighs right. Mix like bondo with the paddle - good to go. Sticks break too easy for me.

After the board dries the proseal peels off easy. Same for the hand paddle. Reused many times. I think three hand paddles come in the bondo paddle package.
Click to expand...
 
Mix to color...

I measured by weight for the first few. I noted roughly the size of the sealant and catalyst and from then on mixed based on visual size, and verified by matching the color.

Been flying 1.5 years no leaks. Actually I did have a leak on the fuel level mounting plate but it didn't have anything to do with the sealant.

Michael-
 
Cleaning Aluminum for Flamemaster tank sealant

I received my scale and I will start my fuel tanks soon

http://www.affordablescales.com/sho...60_Wxx23q6jISRyzO1_xQaAgLV8P8HAQ#.VokcWuRIiF6

I have some questions on cleaning the parts

Vans instructions

Then thoroughly clean all the parts (including rivets) with naphtha or MEK
or an etching acid like Alum Prep or Twin Etch. After cleaning, do not pollute the areas to be sealed. Don’t even touch them. The oils from your skin will affect the bond of the sealant.

1. Will Acetone do a good job or should I buy Alumiprep no. 33 from
Aircraft spruce.

2. How do you clean the rivets, do you just wipe them with Alumiprep or do
you need to scuff them first with scotch-bright pad and then clean.

3. Do you need to rinse the after etching.

4. What works best

This is new territory for me, any help will be appreciated

Joe Dallas
 
Last edited:
As suggested, naptha or MEK works fine. Acetone is probably OK as well. I have a partial gallon of reducer left over from an auto painting project years ago; that works great. You just want something that will remove all contaminants from the surface. Naptha (mineral spirits) works well because it doesn't evaporate as quickly, so you have time to wipe it down with a dry rag before it evaporates. I scuff the sheet metal with a Scotchbrite pad before cleaning, but not the rivets. Those just get dunked in solvent and air dried.

If you get really ambitious and use an etching solution (I wouldn't, but to each his own I guess) you'll definitely need to rinse the parts afterward.

This is not a really challenging or unique thing. Like any other time you use an adhesive or paint, you want the metal to be very clean, and the mating surfaces should be scuffed.
 
Mineral spirits is not the same or similar to naptha. I would not use mineral spirits as it does not flash well and leaves a residue. Naptha (Coleman fuel). Mineral spirits (Charcoal lighter).
 
I stand corrected... I do use mineral spirits for cleaning, but follow it with a wipe down with acetone, MEK or more often paint reducer to remove any film.
 
a couple of follow up questions

I bought a gallon of MEK for cleaning the aluminum.

I did a test try of mixing and sealing a test joint
This will not be my most favorite thing to do

a couple of follow up questions
If I paint the tank will it harm the tank sealant
Will the tank sealant bond to tank sealant to add a little in the corners.

Thanks
Joe Dallas
 
joedallas said:
If I paint the tank will it harm the tank sealant
Will the tank sealant bond to tank sealant to add a little in the corners.
Click to expand...

That's one of the great things about tank sealant. It's paintable.

Yes, tank sealant will bond to tank sealant.
 
I used the Harbor Freight scale as others suggested and it worked fine. It no longer looks new though since there is black residue all over it. I'm glad I didn't spend more. :D
 
Here is a picture from a spec showing how things should look when you're done.

2612t6g.jpg


We typically use type B sealant, and that's the thick stuff. Type A sealant is more of a honey-like consistency and I used it in a syringe to go over rivet heads and edges. Worked well and sticks to cured type B nicely. Once cured, the two are indistinguishable.

Dave
 
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