Walrus class 1/60 scale - Scaleshipyard

[salmon]

The times I ran the sub (with the tabs) the epoxy never became soft. This sub would run for 3 to 4 hours. Anyway, I had to change when I moved from a Z cut to a centerline cut.
Close rRalph, the Sjöormen is the one I ran last weekend, this thread is about the Walrus.

[lhdockyard1]

I have found that the quality of the epoxy has a great deal to do with the softening issues. I have experienced those issues with cheap off brand or store brand epoxies but with good quality, name brand such as Z poxy and others I have never had any trouble as long as the cure time was 15 minutes or longer. The environment in which the epoxy is cured in also affects the outcome. The hotter and most importantly the drier the environment is during the cure the stronger and more resilient the bond will be. Worst thing is to try and use epoxy during humid conditions.
Just my 2 cents

Don

[crueby]

I have found that the quality of the epoxy has a great deal to do with the softening issues. I have experienced those issues with cheap off brand or store brand epoxies but with good quality, name brand such as Z poxy and others I have never had any trouble as long as the cure time was 15 minutes or longer. The environment in which the epoxy is cured in also affects the outcome. The hotter and most importantly the drier the environment is during the cure the stronger and more resilient the bond will be. Worst thing is to try and use epoxy during humid conditions.
Just my 2 cents

Don

Same experiences here with the hobby-shop 5-minute stuff, lots of strength and softening problems.

After using it with full size boats, I have switched all my epoxy over to be either System 3, MAS, or West Epoxy, which are made for the boating market, never had any issues with them at all. Mostly I use the System 3 Silvertip epoxy now, no amine blush/wax issues with it which saves a lot of hassle - have used it on my full size boats (kayak, sailboat) as well as made RC hulls with it. Well worth the longer cure times. For small jobs and gap filling, the West G-Flex epoxy is very handy, comes in small bottles, works quite well.

With any epoxy, shelf life is a concern, it does not last forever in un-mixed state - buy in quantities that you will use up in a year, toss any old stuff.

[salmon]

I thought my West Systems epoxy was bad when it had a brown color to it, but West Systems said that it was still good and sure enough it worked!
Inspecting the hull There were many areas I would need to fix, but I consider this hull a learning hull. I never worked much with fiberglass and as I have hulls needed to be built that are, there is no better time than now to learn.




Also there were pits and bubbles that will need to be addressed. As it is, I did not fill all the pits. It seemed every 100 I filled there were another 100 that popped up.
The epoxy on the surface originally I tried sanding it out, but I found an edge of a file could knock off most of it.

[salmon]

Not different than most subs, it seems, there are a lot of flood holes. I have seen some just put a few big holes along the keel and be done with it (nothing wrong with it especially after working on this one). I choose not too. Again, learning as I go.
I put several holes inside the squares that needed to be filed out Then began the process of filing.


After I do not know how many I questioned my decision to file them out. So, I would work on 6 or so squares and take a break (like next day). Just small steps will eventually get me to the finish.

[Ralph --- SSBN 598]

Huhh all submarines look alike! ;^) Don't they?
==============
Today at the pond, I had an idler gear frees up on my Skipjack.
Out of commission until I find the problem (not the idler gear. That was a speck of sand that ground up on the shaft and bearing)
The issue is the ballast controller needs to be reset.
============
Epoxy bonding problems.

When building full size experimental aircraft, there is a cloth that is laid over the epoxy while wet and smoothed out over the epoxy.

After it cures, the cloth is removed basically breaking all the epoxy that wicked through the cloth leaving a surface that has about a 85%+ clean surface.
No sanding required.
In fact sanding is discouraged because it leaves dust on the parts to be epoxied again.

[salmon]

I think one of the best parts of posting a build is the discussions and sharing of knowledge. I learn from you.
When I build, sometimes I slog through and make mistakes and sometimes there are successes. I document both so all can learn. I so appreciate the wisdom shared. My next fiberglass sub is the SWM Blueback 1/96 scale. So what I learn here will be used on that build. That build will be a live build, meaning I will post as I go along. The Revell Type IX needs to be finished along with a Seaview. Then Blueback. That is the plan in my head.

[JWLaRue]

Epoxy bonding problems.

When building full size experimental aircraft, there is a cloth that is laid over the epoxy while wet and smoothed out over the epoxy.

After it cures, the cloth is removed basically breaking all the epoxy that wicked through the cloth leaving a surface that has about a 85%+ clean surface.
No sanding required.
In fact sanding is discouraged because it leaves dust on the parts to be epoxied again.

Ralph, what you are describing sounds like applying epoxy on a wood surface with the attendant issues with wood dust? If correct, then there are different issues with a fiberglass surface.

-Jeff

[Ralph --- SSBN 598]

Jeff, it was epoxy on epoxy laminates on experimental aircraft.
The cloth was place over a layup then cured.
Then the cloth would be pull up and off leaving the surface with all those broken epoxy points.
The next layer did not require sanding or prepping.
Just pour epoxy and spread out.
Place the next layer of fiber cloth on and squeegee it to get the epoxy to come through.
The excess epoxy would be on top of the cloth and break off when pulled.
There were times we put the parts in a big plastic bag and use 3 or4 shop vacuums to suck the air out.
Even used sheet plastic drop clothes taped together to make big bags.

If I remember correctly, the process was a Burt Ratan thing. (1970-1980s)
Used on the canard planes.

[salmon]

Ahhh, Ralph I know what you are talking about! (I think - is this it?)
From this site:

https://www.fibreglast.com/product/vacuum-bagging-equipment-and-techniques-for-room-temp-applications/Learning_Center

[JWLaRue]

Ralph,

Ahh....I understand. It's a/the method for creating multiple lay-ups of glass cloth and epoxy. That's a technique worth remembering.

-many thanks,
Jeff

[Ralph --- SSBN 598]

That is very similar to what we were going.
There was no mold.
Jigs were made to hot wire all the foam pieces.
They were assembled and then glass layup began.
The foam and wood stringers where inside and left there.

[thor]

The cloth is called peel ply. It removes the amine blush and properly prepares the surface for an adequate mechanical bond. A word of caution; not all peel plys are created equal. Avoid the cheap versions from Asia. They are useless and do not perform the job properly.

[salmon]

Matt, what company or brand do you recommend or use?

[thor]

https://www.fibreglast.com/product/Polyester_Peel_Ply_583/Vacuum_Bagging_Films_Peel_Ply_Tapes

Or:
Not nearly as good a secondary bond capability, but easier to work with.

https://www.fibreglast.com/product/econostitch_peel_ply/Vacuum_Bagging_Films_Peel_Ply_Tapes