Fibreglassing - a Dumb Question

dankilb said:
It's the least-known hyper inflation indicator around...!

A roofing supply place around here ('Chestnut' on Merseyside) still have a gallon under £20. It does last enough to justify the initial outlay, even for smaller jobs (and it sounds like you may have a few!) - providing the First Mate doesn't forget to put the lid back on, as happened to me the other week!
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Way back in 1971, I had my first job at the laboratories of the long defunct Coal Tar Research Association. We were measuring the physical properties of various blends of coal tar, asphalt and additives such as PVC. Needless to say, a wide variety of solvents were needed to clean apparatus and hands! We got through trichloroethylene, xylene and acetone in 44 gallon drums. You'd never be allowed to use trichloroethylene these days and xylene is a cancer risk.
 
Depending on financial restraints you can actually wipe of as much as you can with a rag , remove roller from handle and allow both to dry out then chip the hardened resin off , not as difficult as might seem , and free ?
 
I’m on to the last two coats of a nine coat epoxy osmosis treatment / barrier coat, plus a host of interior structural grp work (e.g. literally a dozen separate bulkhead/tabbing repairs or replacements!) all with epoxy. So I’ve learned to economise the more experience I gain and the more prices have gone up!

I second all the above suggestions that simply wiping off can remove most of the mess. Decorators’ merchants sell clean recycled rags that are good for a variety of jobs…

Eventually either heat or mechanical means will be required to ‘recover’ whatever tool to a usable state (or this is the time to bin and replace). I’ve found this to be the case even when I used to soak tools in acetone… eventually they get still got ‘laminated’!

Other ways I’ve come to economise include using car paint/body panel wipe (‘prep solv’ to some) instead of acetone as a general prep solvent. It is benign enough for more sensitive paint systems and can be had for under £15. Works as well as acetone as far as I can see.

Mirka Autonet (the cheaper older brother to Abranet) has also saved me lots on sanding, with 50 mesh discs for £20 at a local auto paint/body place.

And EL2 resin from Easy Composites, of course. Well liked by many connoisseurs on here and around half the price of West’s. The First Mate particularly rates its low viscosity!

I have been beaten by nitrile glove inflation though, and so plump £30 for 50 ‘Black Mambas’ on the basis that I usually ruin them before they break and that way I can long them out at my discretion.

So, I’ve found a few economies to make along the way - not that epoxy work could ever be said to be ‘cheap’. Hope it helps others.
 
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While I endorse the use of rags for cleaning beware of their exothermal/incendiary properties once contaminated with resin; either keep them outdoors or store them in a metal bin.
 
cherod said:
Depending on financial restraints you can actually wipe of as much as you can with a rag , remove roller from handle and allow both to dry out then chip the hardened resin off , not as difficult as might seem , and free ?
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I have removed cured resin from plastic mixing bowls and spatulas by softening with boiling water and peeling it off.
No use for brushes though.
 
With bowls/mixing pots the trick is to run the spare epoxy around the inside (if too much then decant some into water to reduce exotherm issue). Once the epoxy in the pot has hardened then just flex the pot and it should come out in one piece.
 
Yes, vinegar works well. I have used acetone, but Vinegar is my preferred method for cleaning tools. It takes very little, and working in the boat yard, makes less mess. You don't need "crazy amounts" and lots of rags.

Pour some vinegar on a coarse scrub brush and scrub briefly. It takes very little. This will deactivate the cure and the stickiness. The epoxy will turn white. Then scrub with soap and water. This also works for wiping down areas where you might have spilled but are not certain, and for skin, where large amounts of acetone are both irritating and a serious fire hazard. For example, wiping down a boat interior with acetone is not very safe.

I also use acetone for quick wipe-ups of drips. I am NOT going to say there is only one way.
 
Hacker said:
With bowls/mixing pots the trick is to run the spare epoxy around the inside (if too much then decant some into water to reduce exotherm issue). Once the epoxy in the pot has hardened then just flex the pot and it should come out in one piece.
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Very true, this. When it comes to pots, the more you wipe (and the thinner the epoxy remnant) the harder it is to remove!

I was stumped by pre-mixed fairing filler though… so expensive, you don’t want to waste any. But the thin layers I left behind in the roller trays I was using, plus potentially the ‘keying’ action of the filling knives on the plastic, meant the filler properly adhered and trays were unrecoverable. Sorry Captain Planet!

Thanks to this thread I will try both vinegar and warm water next time. Even at 30p or whatever for a pot/tray, it all adds up.
 
When I started to lay up the hull of my yacht I got a professional f/g layer in. He used home-made rollers made of the thread of (about) a 10mm bolt, a hole drilled in each end and a steel handle similar to one pictured. And that is how I finished the rest of the hull on my own. I believe they work a lot better than anything I've bought (maybe because the thread disperses the resin?)

I always washed them in acetone at the end of the day but when I forgot (occasionally) I burned the cured resin off with my butane torch.

These days I use cheap soft rollers and dispose of them when I'm finished rolling.

Screenshot 2021-11-18 at 15-54-49 Diy Fibreglass Roller.png
 
An American boat builder friend taught me to laminate. He told me a story that when they were building high spec carbon epoxy skiffs the cost of acetone was crazy and they bought it in 50gallon drums. They found out that white rum was just as effective so bought a drum of that as it was cheaper than acetone ?
 
geem said:
An American boat builder friend taught me to laminate. He told me a story that when they were building high spec carbon epoxy skiffs the cost of acetone was crazy and they bought it in 50gallon drums. They found out that white rum was just as effective so bought a drum of that as it was cheaper than acetone ?
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And nicer to relax with after a day's work.
 
Many epoxy jobs later, I still have the alloy rollers I bought 25 years ago. Cleaned with vinegar, followed by soap and water, every time.

Bin the chip brushes and flex the pots and spreaders. I've even used it to get partially cured epoxy out of my hair. I can't imaging dumping acetone on my hair, followed by multiple rinses. A quick scrub with vinegar, followed by soap and water, is not bad.
 
Thanks, everyone.

The layup is done, with a 20w halogen light on it to help it cure overnight - I'd have liked more, but couldn't find the right kind of bulb. Next step is to do a couple of reinforcing bars in 30 x20mm pressure treated timber, with a few layers of glass cloth over them. I've rounded the top edges to help the cloth fit nicely and coated them with epoxy to help with adhesion. Tomorrow, I plan to fit them and build fillets in the same thickened epoxy I'm going to use to and stick them down. The weather's looking kind to dumb epoxiers again tomorrow, but then it turns a good bit colder, so I'd like to get everything done tomorrow, so dumb question no. 2 is, Can I put the layers of cloth over the bars before the fillets have cured, or must I wait for them to go off? Appearance is unimportant, but structural integrity is. Dumb question, no 3 is, How many layers?
 
Stemar said:
Thanks, everyone.

The layup is done, with a 20w halogen light on it to help it cure overnight - I'd have liked more, but couldn't find the right kind of bulb. Next step is to do a couple of reinforcing bars in 30 x20mm pressure treated timber, with a few layers of glass cloth over them. I've rounded the top edges to help the cloth fit nicely and coated them with epoxy to help with adhesion. Tomorrow, I plan to fit them and build fillets in the same thickened epoxy I'm going to use to and stick them down. The weather's looking kind to dumb epoxiers again tomorrow, but then it turns a good bit colder, so I'd like to get everything done tomorrow, so dumb question no. 2 is, Can I put the layers of cloth over the bars before the fillets have cured, or must I wait for them to go off? Appearance is unimportant, but structural integrity is. Dumb question, no 3 is, How many layers?
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Be warned that pressure treated wood is wet clear through and not kiln dried. Unless the wood has been on the shelf, drying for a year the moisture may cause trouble.
 
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