Sanders?

[BWCA66]

I helped out on one strip canoe and am now helping out on another and then plan to do my own. Both times the sanding was done either with a random orbital sander or by hand. I'm looking at getting a sander or sanders but thought I would ask here first what all of you use? What about a high speed disc sander - wouldn't that be faster or does it take of too much? Think I saw a belt sander in Robin's hand in one of his pictures. Any input would be greatly appreciated.

 

[Robin]

I don't know about strippers but I use a palm sander, belt and orbital on wood canvas...and also by hand.

 

[Mihun09]

RO sander and by hand mostly. I have used a belt sander when shaping stems though. I did make up a special head for my detail sander for between the ribs and it works ok but doesn't apply to a stripper. I used scrapers on the stripper we built a few years ago to knock down high edges as well, especially on the inside. If you can get one of the soft pads to fit the RO it helps to alleviate only using the edge of the disc.

My Ryobi RO sander ran fine for 3 years before the bolt holding the pad on broke, replaced that but now it throws discs since the velcro is worn out. The DeWalt I replaced it with last year isn't as aggressive as the Ryobi but it is fine for what we do.

We are thinking of building a stripper over next Winter. Make something new instead of working on old stuff all the time.

 

[Alan Gage]

I had a cheap Ridgid ($80) orbital sander and it conked out after two strippers. In terms of performance it seemed to be on par, or maybe a little better, with other orbital sanders I'd used in terms of vibration, noise, and on board dust collection. Sanding was not a task I looked forward to and I wore a respirator to deal with the dust.

When that one died I bought the sander I wanted to get in the first place but couldn't justify at the time, a Mirka Ceros. Very expensive and very awesome. I could not be happier with it and if someone stole it today I'd buy another one tomorrow without hesitation. The small size and light weight make it easy to hold on horizontal or upside down surfaces and gives you much more control. It gets into tighter spaces.

I have it connected to a cheap shop vac for dust collection and it's amazing the amount of dust that's collected. Cedar dust will have my nose running and give me a nagging cough within a couple minutes if I start hand sanding without a mask yet I can sand for 3 hours straight with the Mirka, using no mask or respirator, and have no issues. The shop stays much cleaner and I don't even have to blow the dust off my clothes when I get done.

I didn't think I'd have much use for the variable speed but I've really grown to like that feature. If I want to remove a lot of material I can crank it up and if I'm working with softer or thinner material or an outside curve where it's easy to cut too deep I can turn it down.

It's the quietest, smoothest, and most powerful sander I've used (not that I've used a lot of different ones). Believe it or not I almost look forward to sanding now (except the inside), it's a real pleasure to use. Along with the standard pad I also have a soft pad as well as interface pads (really soft) and I've begun to reach for the orbital when I otherwise would have hand sanded only, like rounding over edges and sanding curved surfaces like shaping the stems or sanding gunwales. I think the size and weight have a lot to do with this as this seems to make it much more controllable.

That's pretty much the only sander I use. I do of course still hand sand at times and I have a belt sander but I use it less and less each build, not once on my current one. The general wisdom is to never use a belt sander on the hull. Things can happen very fast with a belt sander and I believe it's harder to have a delicate touch. Momentum used one to sand the outside of his hull but he has lots of experience using them as a furniture maker.

I wouldn't use something like a high speed grinder. You're working with cedar after all, it sands pretty darn easy. You'd need to finish with an orbital anyway to remove all the scratches.

I start with 40 grit and that removes material plenty fast. I had a hard time finding anything coarser than 60 grit and when I did the quality was very poor. Now I've bought some 40 and 60 grit discs from Industrial Abrasives (http://www.industrialabrasives.com/) and have been very happy with them.

Alan

 

[Jamie]

I use all types of sanders, mostly just so I don't have to change grits as often. They all get the job done to some extent. My only advise would be to get good quality sand paper, the little extra you spend is well worth it.

 

[sailsman63]

Whats been written already is a pretty good primer.

To reiterate:
Belt sanders are very aggressive.
They can gouge into an oak surface if one is not careful.
They need to be kept moving at all times, are heavy, and the platen (surface behind the belt) is designed to work best on flat surfaces.
They also tend to pull forward.

Advice from someone who does use belt sanders on his other projects: would not recommend unless you already have experience using one.

I have gotten some use out of a sander that is basically a rubber backing disc that mounts in an electric drill - really nice when the inner bilge curve was messier than I had hoped - but even that is more aggressive than most people need.

Of all the options, a decent RO, (and as some suggested a softer backer for the inner curves, if you can find one) is probably the most versatile and forgiving of the sanders, especially for a beginner.

Palm sander - didn't have one around for my builds, but may use it for finishing work next time, as my RO tended to build up a little too much heat for the epoxy. Palm sanders are less aggressive than an RO, and would take a lot of time if used in the fairing stages... Though, when strip building was a newer technique, people used them for that, as ROs were not commonly available.

Luke

 

[BWCA66]

Thanks for the comments. I have used my belt sander enough to know it should never get near cedar! I have a palm sander too but I also have an air powered disc sander that I was guessing would be a lot like my belt sander and since no one commented that they use one I guess I'll pass to, would need a larger air compressor anyways. Alan, I looked online at the mircas and I think I'll just go with a cheaper orbital this time. Now if I get hooked on this and there are more builds I'll have to look into them.

Thanks again everyone.

 

[Jim Dodd]

Wish I could talk Alan in to coming down, and giving me a demonstration on how well that Mirka Ceros works !

I've got a lot to sand ! I'd want to be sure it could do Kevlar, before I invested in one !


Jim

 

[sailsman63]

@bwca66: I'd guess your air powered disc would be similar to my drill disc, but more powerful. Might want to check, though, I have seen some air powered RO sanders around, If you have one of those, it would work great.

Luke

 

[Alan Gage]

Wish I could talk Alan in to coming down, and giving me a demonstration on how well that Mirka Ceros works !

I've got a lot to sand ! I'd want to be sure it could do Kevlar, before I invested in one !


Jim

I'd be happy to. We can see how long it takes to turn your new boat into a fuzzy ball of kevlar yarn.

Alan

 

[Jim Dodd]

I'd be happy to. We can see how long it takes to turn your new boat into a fuzzy ball of kevlar yarn.

Alan

Alan ! You have too much respect for a canoe to turn it into yarn !

I did get into the weave, in a few spots, especially around the wrinkles, needed one more coat ! Said that a lot of times !

Spent about 2 1/2 hrs sanding yesterday, and about 45min left today.

Speaking of fuzz ! I bought Kevlar felt from Al, at North West Canoe, years ago. We discussed how hard it was to sand, once on the hull.
One suggestion he offered was Polyester felt, available at every fabric shop. It would add thickness to the wear area, and yet be sandable. Not as durable as Kevlar, but at least workable. Food for thought !

Stretching saran wrap over the Kevlar while the resin was hardening was the best we came up with at that time. No vacuum bagging yet.

Used an old variable speed 5" RO yesterday. I do like slowing it down. Just seems easier to handle, and with a slight noise reduction.

If I've learned one thing building these canoes ! ANYTHING you can do to reduce sanding go for it !
A Female mold, and vacuum bagging, would pretty much be the ticket !

Jim