Sanding Fiberglass and Staying Clean

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Wimperdink
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Sanding Fiberglass and Staying Clean

Post by Wimperdink »

Sanding fiberglass is NO fun!!! Its itchy and dirty and just not an indoors job.

We had no choice in the matter so we had to make it an indoors job so here's what we did.

I use a Skill brand random orbital sander, (walmart special) which is my best friend when it comes to smoothing fiberglass. As it turns out when you take the filter off, the round end that sticks into the filter is the perfect diameter to slide the end of my shop vac hose over. I outfitted my shop vac with the normal foam filter, and the paper prefilter that goes over it, then added a sealed bag, (see the shop vac section at your local walmart) that makes all the vacuumed debris go inside a bag instead of inside the vacuum. Then I cleaned the vents that the outbound air comes out so I could judge how much fiberglass dust was getting by. To my surprise, with two sanders setup this way, two of us were able to sand the whole inside of the boat without coveralls and dust masks, (I dont reccomend not wearing a dust mask when sanding fiberglass) and without so much as even a light dusting on ourselves. The exhaust ports on the vacuum didnt even get dusted. The only thing that slipped by was a tiny bit of dust that seemed to statically attach itself to the outside of the vacuum and any big pieces of wood or glass that were too big to get vacuumed up through the holes in the sander.

I will not sand fiberglass any other way ever again. A few hours of sanding and I'm not the least bit itchy. :D What you see dusted on the vacuum was 99% of what slipped by.

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Kayak Jack
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Post by Kayak Jack »

Wimperdink,

BTW - I like the name. Where did you think that up?

I'm thinking here that you are sanding off the very stuff that is supposed to remain on, and provide strength to your boat. You shouldn't be getting fiberglass off. Sand down the excess epoxy, but don't cut into the fiberglass. It's supposed to remain.

I do like your idea of attaching the shop vac to the sander. I think my sander exhaust (currently sleeping peacefully in the basement) is square, and my shop vac hose is round. You were lucky.

A trick you can use to test for foreign matter escaping your shop vac, is to apply a light coating of white, l-i-t-h-i-u-m grease to the exhaust port. Any matter coming through will leave traces in the grease and it's easy to see.

This technique works also to see if anything gets through an intake filter, and into any mechanism that is supposed to be dust free.
Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.
Wimperdink
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Post by Wimperdink »

Well I've used some thick mat instead of cloth in places and some of that has to be smoothed out before being reskinned again. Another part of my problem is i'm not using epoxy. I'm using that other stuff that we dont like to talk about around wooden boat building :D I'm too sloppy to be able to afford epoxy. I had problems with cloth floating on another boat that had to be sanded off and redone, hence the itchy. :D Anyway with two people sanding in a small one car garage, we didnt even get dusty using these vacuums. My brothers sander has a square end coming out to his filter so we modified one of the hose ends we had laying around and just duct taped it to his and it worked out fine. Its a mini dust collecter :P

I'll have to try the l-i-t-h-i-u-m (spam?) grease trick and see if that collects any more than it did before.

I'm not sure how I came up with this name but I've had it for about 9 years on the internet. :roll: I've noticed there's at least 2 more wimperdinks floating around now too.

Not as pretty but works just as well.
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Kayak Jack
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Post by Kayak Jack »

I like your adapter - handyman's secret weapon - DUCT TAPE. (You DO watch Red Green on PBS, don't you??!!)

Only time I've ever had glass that needed sanding was one time when I used tightly woven glass on the inside of a boat Never again. Loose weave will wiggle around and reshape itself to conform to the curves - whether concave or convex - and fit the boat. Tight weave initially fitted, then re contorted itself. This left bubbles of 1/2" - 3/4" all around the inside of the boat. Major bummer.

My experience would suggest that I can't afford to not use good epoxy. I've used both System-3 and RAKA. Both are high quality and work. Very strong hulls that take a beating of rocks, beaver dams, logs, carrying from stem ends while fully loaded (boats, not me), and general abuse.

I also believe in very good Okoume mahogany plywood, and loose weave glass. These three components assemble into one helluva strong hull. I believe in two words - hull integrity. If a boat don't float, my day gets really bad from there on in.
Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.
lncc63
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Post by lncc63 »

Our solution so far has been to coat ourselves with talc powder. It works at least 95%. The way I understand it is the talk clogs your pores preventing fiberglass dust from getting into them. In our high humidity climate, the power is of course also refreshing.

I said only 95% because I still get some itches around the neck and on the face especially on a windy day. Recently, we also added to our procedure wiping off the dust as it builds up with a damp cloth, I'd say we now avoid 98% of the itch.

Next time I'll try the vacuum with the sander. It may just get the remaining 2% and take the itch out of sanding.
Louis
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