Tool Recommendation Please

I have a bare 46’ composite hull and am ready to start installing stringers and bulkheads. To the extent I can, I would like to sand all of the hull areas that will receive tabbing before I move the hull into the shop and start attaching things. The hull is vinylester and I will be tabbing with epoxy. Questions: What sanders and what grit is recommended? I see Festools and Fein recommended in other threads. I value good tools and don’t mind paying for them but on the other hand, this is a one-off affair for me so they won’t be in production use. Your input is appreciated.

SeaJay

 

I don't know what grit you should use but I would start with 80 and go from there, if no one else chimes in. For a one time sander go with Sears products. They have a good warranty and will replace broken units. I do not recommend Sears for permanent, long lasting tools but they should be fine for your use and are reasonably priced + warranty.

 

Rigid is Home Depot's brand. They are guaranteed for life. A bit more money, but foolishly, they are really lifetime guaranteed. i guess because so many weekend warriers never use their tools like I do. I've gone through plenty of 4 1/2" grinders.

 

I personally would not use an electric tool. The dust created by sanding does a number on the motor. If possible, use an air tool.

 

Porter Cable 6" Random orbital sander/polisher. This is a finish sander.

Then if you want to get rid of a lot of material fast, Hitachi Vertical Disc Sander. I just got one off the web for $50 including shipping. Wish I had known about it at the start of my build.

Blow the dust out of the housing every so often with compressed air.

 

wire wheel attached to your preferred angle grinder will work wonders. Just make sure you're careful or you'll go through the hull in no time.

 

Not sure what the surface is like, but a good old Makita 4 1/2 inch grinder with a stiff backing plate and a 36 grit disc works for me. I have several they hold up very well.

 

You probably can't afford a Festool anymore. Their electric triple action is now over $600 US

But never fear; Makita now has a knock off of the Festo, their BO6040 which sells for around $300. This sander will do all of the tasks needed to build and then finish a boat, so it's really the only sander you will need.

Jimbo

 

Random Orbit sanders are great, but the question had to do with prepping for glassing. I've used a lot of brands of of (4") angle grinders and they all worked fine. Even in a bad fg dust environment, all survived to go on for a few years. That said, I never used them exclusively for fiberglass, mostly metal. But maybe you will not be doing glass every day either.
Air tools use a LOT of air and you need a big compressor. Electric will cost maybe 49 bucks if you shop around--- Makita, Rigid, Porter Cable, Milwaukee, etc..

 

Thanks

Rasorinc – 80 grit is what I was planning to start with. I’ve seen it recommended by Gougeon.

Alan – I have a lot of Rigid tools and have been pleased with the quality

Eagle – I don’t presently have compressed air in the shop, but am considering it. Electricity is via a portable generator so I have to watch my watts. However I do like the weight savings of air tools. I’m going to get aggressive about dust control and plan to use a vacuum hook up to the sanders.

Nero / Blaze / Pescaloco – I like the idea of removing a lot of material in a hurry. However, a lot of this work will be done by hired hands so their concern for the 3/16ths of an inch of fiberglass they’re working on is worrisome. I’ll test these methods and see if I trust my guys with these tools.

Jimbo – I think this Makita is the workhorse I’m looking for. I’ve got a number of smaller sanders that can fill in where appropriate. Interesting…the Makita about a pound heavier than the Festool. I suppose that’s why the Festool is twice as much.

 

I usually use 24 grit for prepping. It saves a lot of time and money

 

I used to do a lot of grinding at a place I worked at and Like gonzo says, 24-36 grit. My procedure for fast grinding and max comfort was to bear down on the tool (6" discs) to a point a little above where it would stop rotating. I'm sure it was hard on them but they weren't mine, and even though we only used 'cheap' Sears tools, none of them ever burned up. The slow speed and high pressure ground fast and most important, the slow disc speed didn't create hardly any airborn glass.

 

I just remembered, I bought 50 grit discs to prep for a reinforcing layer or two at the angle between centerboard and bottom, inside a 12 ft O'Day sailboat. 80 grit? Too fine, and 36 was too aggressive for this job. Not all jobs are the same.

 

Angle grinders with sanding disks and sander/buffers with bigger diameter sanding disks. These are the tools of the trade when it comes to bulk material removal and roughing up surfaces. The lowest grits work best. 16, 24, 36 and 40 will do a lot of damage fairly quickly, so be careful. You can make a career out of higher grits, they just don't move enough material. Tabbing locations don't have to be pretty, just well "toothed" and clean. As Alan said you can be too aggressive, but this can be controlled a great deal by how you work the tool. With a 7" disk and 16 grit, you can move at a rapid pace and in one or two swipes down the surface have the deed done. You'll probably be safest with 24 to 40 grit if using these tools is new to you.

For you project, I use a fairly small electric, inexpensive buffer/sander. It's low amperage will be kind to your power supply and they don't cost much. If after 40 bucks, you've got the job done and the Harbor Freight cheapo sander takes a dump, you will not feel so bad.

 

The Festool RO150 and the Makita BO6040 are no mere 'random orbit ' sanders; they are triple action beasts that with the flip of a switch change action from random orbit to epicycloid (geared orbit) to true rotary grinder/polisher.

Jimbo