TOPIC: Hardtop progress/dust collection question

The plan was to work today and try to get caught up. However, I got distracted and decided to do some work on the Glastron hardtop. I removed the border trim and started removing gel coat. I was using an angle grinder with #24. Worked well, but did generate a lot of dust (may have to buy car washes for a couple of neighbors). Has anyone tried the dust collectors for angle grinders? That could make life a lot easier.

I have 3 different dust collection systems for angle grinders that I use. one is simply a shop vac hose duct taped to the head of the grinder and hooked up to vac. I use the smaller 1 1/4" hose. easyer to handle. The second system is a drywall sanding unit that sucks the dust into a bucket of water. Again I just tape the hose to the grinder head. There are 2 sizes of these systems and I use the smaller unit as it is easyer to use. Menards/ home depot. The third system that I have is a factory made dust colector made for angle grinders and I find that it is the least usefull system. It doesn't suck up as much dust as just the hose taped to the head does. My favorite is the second system as then I can use it just about any where. The only hard part about useing these systems is the hose must be fairly flexible and small diameter. The big 2 1/2" vac hose is just too bucky to use. I did have a grinder with a bag on it, junk. Bag did not last long and I was always emptying it and it really didnt collect too much dust. Hope this helps you and good luck and keep us posted on your project. Skip.

I used dust collection with my sander, but not with the grinder yet. One thing that I DID do was add a HEPA filter to the shop-vac- it made a HUGE difference in the amount of dust that stayed in the vac. They are pretty pricey, and get clogged fast, but you can clean/reuse them. Having a dust collection system made all the difference in the world, though.

I second the small hose thing- The big stuff it hard to work with.

It didn't take long to figure out that even WITH the dust collection system on my sander my garage is still a royal mess with the dust. I thought about getting one of those "garage in a box" kits Todd, and putting an exhaust fan (with filter of course) in one end, for sanding and painting boats. Just isn't in the budget though...... will wait for warmer weather and set up a big fan to blow it toward the woods in the back yard.

Skip, I can't figure out how duct taping the hose to the grinder head will do anything. If you could post a pic, that would be helpful. Mark, I hear you about the mess in the garage. I'm not going to do any major sanding inside. However, I still want to use dust collection because of the major amount of stuff this process produces. The plan is to strip the top since the weather is going to hold for at least another week, then put it away. In the spring, I'm going to have to start on the deck as most of that will need to be stripped as well.

I do it a little differently. I wait until a good stiff breeze is blowing towards my neighbors new cars and then I go to work. He is an asshole. When I mow grass and kick up dust I go over that spot multiple passes. He says he cannot be seen in a dirty car so he washes them all the time.

i was just looking at this garage vacuum at Ollie's outlet,for 99 bucks,i have been looking at the web and it keeps getting high ratings,so this might work pretty well for dust collection,its a bissell wall hanging wet/dry vac.john

Ok, are afew pics of the grinder dust collector I use. You will n eed 4 things to do this. 1- Grinder. 2- 1 1/4" id. elbow. 3- 1 1/2" id vac hose. 4- Handymans secret weapon.
[img] [img]http://www.fiberglassics.com/media/kunena/attachments/legacy/images/boat_grinder_029-20111227.JPG








That is the simplest one that I use. I works pretty good, but it will not get 100% of the dust, mybe 75%. Better than nothing. If you need more dust gone you will have to buy a enclosed vac. tent with positve air flow to draw all dust out. Skip.

hey that looks like that classic Japanese para scope used on a mentor?

Bathtub fitting?

that or a kitchen sink, double sink.

Hey Skip,

Red Green would be proud of you!!! "Duct tape is like the force - its got a light side, a dark side and it holds the world together."

Kinda hate to admit it, but he's a good a good friend of mine.

Kinda hate to admit it, but he's a good a good friend of mine.

Duh, double post, sorry.

OK. I tried to build a dust collection hood from a $2 plastic bucket from the hardware store. Not very successful.I have one other mod to try to get it to work before I scrap it. Actually have the top 60-65% stripped at this point.

I'm very concerned that the way you are gringing off the gelcoat is going to cause you major problems. From the pictures, it looks as if you are putting a million grinding mark "shiners" into the glass. This will take a massive amount of fairing and sanding to correct, otherwise the boat finish will look like cobblestone. Have You considered sand blasting the boat yourself, or even better - sending it out to have it blasted? There is also a special gelcoat planer that shaves off the surface a few thousandths, leaving a level and clean layer of fiberglass. No trying to be critical here, just warning against making more work for yourself than intended or necessary.

Bruce

I got the dust collector to work! The attached pic shows what I had set up. The bucket is a 5 qt paint bucket. The bottom was partially cut out and a piece of plexiglass installed over it. The handle (drawer pull) was attached to that. Holes were cut and the 2-1/4" shop vac hose went into one and the angle grinder into the other. Each was sealed with duct tape (yes, black duct tape). It collected probably over 90% of the fine stuff that floats in the air and 80% of the heavier stuff. The heavy stuff could be mostly picked up by turning off the angle grinder and just using the hood.

The down side is that it is not effective on corners, edges and difficult on the small vertical sides.

The remaining stuff I can take of easily with a random orbital with 40 grit.

Bruce, I understand your concern and it is something I wrestled with. A random orbital sander would be gentler and probably required less filling, but the time and material factor weighed in as well. I did the best I could, but there are some areas that will need a fair amount of filling. I accepted that as part of the program.

If there is a sand or other media blasting system that can take off gelcoat without damaging the underlying fiberglass, I'm all over it. The deck on the boat is going to need to be stripped as well and any alternative would be welcome

I Like the grinder bucket - pretty smart. Sand blasting will still eat into the fiberglass, but if done carefully, the surface doesn't have any deep gouges. The most recent picture of your removel work looks pretty good. Sandblasting does a great job, especially if you pay someone else to do it! Grinding FG is a crappy job

thetudor wrote:

If there is a sand or other media blasting system that can take off gelcoat without damaging the underlying fiberglass, I'm all over it. The deck on the boat is going to need to be stripped as well and any alternative would be welcome

Walnuts

Dave, I think you mean walnut shells. Walnuts at 100 psi would be a little dangerous and destructive. There is a media blast company fairly close that works different products. Perhaps I should talk to them.

Way to get after it Tudor! There are a few solutions that guys in a similar predicament with toasted gelcoat should consider...

1. Run from a classic with crazed gelcoat and don't look back.

2. Look for a boat that was painted early on, unintentionally protecting the gel from UV damage.

3. Buy a boat from the less sunny Pacific Northwest, out of a dozen in the armada (1955 to 1963) - only one has lightly sun or freeze damaged gel.

4. If you just have to drag home that vintage beauty, and the gelcoat isn't falling off in chunks: using epoxy resin and light fiberglass cloth as an overlay, create a matrix to fill and reinforce the damage without grinding. There are many ways to fair the surface, with the most time effective being a good high-fill primer in your choice of epoxy, polyester, or urethane. Repaired properly, with this method - the crazing will not return for another 50+ years.

5. Purchase a gelshaver or sandervac. www.paintshaver.com/sandervac.html
The SanderVac can be purchased with or without supplied grinder, the tools bristles support the grinder in a way that helps it "float" above the surface. The windowed grinding discs, allow a great view of the surface. This affordable tool is a must have for the serious backyard boat rebuilder.

Greg

Yes, walnut shells, although whole walnuts would be interesting to watch too...

That sander is pretty cool, they also make a grinder shroud for the grinders which costs about $20-$25.



http://www.dustmuzzle.com/blog/

This one is $29.50, and they have one for $25 as well.

BTW I just ordered the 4"-5" dust muzzle with the hose...I'll let you all know how it works in a few weeks...

https://www.dustmuzzle.com/dust_collector.php

Larry McCay from Vintage Boatworks has tried a variety of media and only to find that sand is the best. Soda did nothing. Nut hulls simply bounced off the glass. The media has to be very sharp to cut into gelcoat & fiberglass. This is because the resilliency of the material. Paint & metals blast easily because of the hardness. Try sandblasting rubber or plastic & you get the idea. Other media like Garnet, aluminum oxide & glass bead work, but the expense of these eliminates them from being practical. Best choice I have come up with - take the boat to a sand blasting pro that you trust. Let them deal with the expensive equipment, dust, and mess. Well worth the money to sub it out.

cc1000 wrote:
"Yes, walnut shells, although whole walnuts would be interesting to watch too..."

Not on my boat.



I'll be interested in your report on the muzzle. The biggest question I have is that you may not be able to see what you are doing, which could be a problem.

"1. Run from a classic with crazed gelcoat and don't look back. "

Except this boat was in my top 5 most wanted list and an hour from my house. hard to pass up.

"2. Look for a boat that was painted early on, unintentionally protecting the gel from UV damage."

Actually the boat I passed on (Todd's cruiser) may have been painted, at least in part.

"3. Buy a boat from the less sunny Pacific Northwest, out of a dozen in the armada (1955 to 1963) - only one has lightly sun or freeze damaged gel."

3000 miles away. Probably cheaper to have the gelcoat removed that buy 6000 miles worth of gas for my truck.

4. If you just have to drag home that vintage beauty, and the gelcoat isn't falling off in chunks: using epoxy resin and light fiberglass cloth as an overlay, create a matrix to fill and reinforce the damage without grinding. There are many ways to fair the surface, with the most time effective being a good high-fill primer in your choice of epoxy, polyester, or urethane. Repaired properly, with this method - the crazing will not return for another 50+ years.

Haven't heard about this being done successfully. It could work, but if not done right, could be an ugly mess.

5. Purchase a gelshaver or sandervac. www.paintshaver.com/sandervac.html
The SanderVac can be purchased with or without supplied grinder, the tools bristles support the grinder in a way that helps it "float" above the surface. The windowed grinding discs, allow a great view of the surface. This affordable tool is a must have for the serious backyard boat rebuilder.


Will probably add one to these to my collection by spring.

This boat had SOME MAJOR cracks.usually we grind all the way to the cloth with a grinder and 30 grit 50 60,,or something that abrasive so we had to do it all anyway But I was told by a smart canadian friend to blast it first and save a week or so. this boat is a 1 of 1 but it was rough,so we tried 4-5 different bags of everything til we hit the black magic, Here is a pic,it took about 1 week out of the project,Then we came back with the grinder and took it all to the cloth and split the hull and rebuilt everything.It is now Gel coated top and sides ,It will be at Tavarres,I was not a fan about blasting but this made me a believer as thick as this was,,Bill

todd after you have it ground down,i use the west system and roll it over the area with a smooth roller then let it find its own level,then sand with 220 grit,it takes a lot of the fairing out of it,john

oopps,it was me in that last post,i was at john "ed" gordons house,lol,sorry,john

We have removed the gel coat from 5 Glassic projects in the last 2 years.

1. 59" Herters Flying Fish, ground all the Gel Coat off with a grinder then had to spend the next 2 weeks filling and fairing to get rid of the damage we did with the grinder.

2. 59 Glastron Seville, Removed the Gel Coat with Air Craft Stripper. It took half the time of grinding, and half the time filling & fairing, but, is truly nasty & dangerous stuff and if not careful it will eat through the fiberglass.

3&4. Sandblasted the entire surface. We cut our Gel Coat removal time in half again. Had to sqeegy? filler on to remove the pitting created by the blasting but again this took half the time that filling and fairing took after chemical removal.

5. 58' Glastron Hardtop, Blasted the entire surface using Glass Beads. No filling and fairing required due to blasting. 2 coats of Duratec surfacing primer and all the minor pitting was gone. This method was definely the fastest and easiest method we have found to date.

We continue to look for an even better way.

Here's the Glastron after Glass Bead Blasting.

Larry
Vintage Boatworks.

Larry,

I really like the sounds of the glass beads. I assume you did the blasting yourself. How did the media cost compare? I'm going to have to outsource the blasting, so I want to get an idea of what I am looking at.

We sent this boat out to a vendor that specialty in media blasting as well as sandblasting. There was no up-charge for using glass beads, We were informed that the glass beads are recycled and re-used up to 30 times before discarding. We were, however, made aware that lower pressures were used in glass bead blasting than in sand blasting, therefore, it would take +/- 20% more time to do the job with glass VS sand. We seperated the deck, hull, and hardtop, to assure the best job possible. He spent 9 hours total, blasting the hull inside and out, the deck top & underside, & the Hardtop.

Larry

We couldn't get glass or sand or cobs to even phase this ole horse,the black stuff was like coal,but I am not to sure he didn't gel coat this with a brush,,he was a one man operation,Larry you might have seen this one, Bill

The black stuff (at least the stuff on my hardtop)seems a lot softer than gelcoat and may not come off with media. Fortunately, I do not have any of that on my deck, but I haven't checked the hull. Larry, thanks for the heads up on what you had done. I am probably not going to dealing with this until spring, unless I find a warm garage and some help so I can take the deck off.

Bill, I do remember seeing NO NAME. The entire boat, as I recall, seemed very sturdy. My first thought " a mini WWII landing craft" LOL Not surprised the gel coat was really thick.

Our Hardtop also had a black coating under the gel ??? Much of it remained after blasting.

Larry