Random Orbital Sander for boat painting preparation

[TandC]

Hello all.

 

Quick question for anyone with experience of preparing their boat for exterior re-painting:

 

 

The roof is badly pitted with two previous coats of badly applied paint flaking off and I've been advised by the boatyard that it will be best to shot-blast the roof and gunnels, whereas the sides are not as bad and can be sanded.

 

Any advice on which Random Orbital Sander works best - is it best to use a normal sized machine - 150mm sanding area - or are there larger, more industrial machines which could cut down the time?

 

I'm expecting to spend a bit more on decent sanding discs (Abranet for instance) and will use a dust extractor.

 

Quick search turns up a number of similar machines in that sort of size, but I havent seen anything particularly larger. While only 45ft long, as always, I am keen to invest in decent tool to make the job quicker and easier so grateful for any advice.

 

Thanks,

 

T

 

[DustyDave]

I've been using a relatively cheap bosch green orbital sander. Does a good job and has lasted a number of years. I'm sure their blue machines are better but while my green machine stays alive that's what I'm stuck with. I have found that spending more on discs is well worth it. Last weekend I used norton discs and they lasted much longer than the cheap toolstation discs. Haven't tried abranet or any of those yet.

 

For going back to bare metal I'm going to try flap discs in an angle grinder as the orbital sander is too slow. The wire cup was too aggressive - it attacked the loose shirt I was wearing at the time (no pics - I was too busy reaching for the mains switch with the grinder wound up on me).

 

Dave

[dave moore]

Hi

 

Bosch do a good one to professional quality for under 200 quid, I recall paying about 160 for mine several years ago. Cracking piece of kit, widely used in many paint docks. I'd buy another!

 

Cheers

 

Dave

[Timleech]

I have a Metabo 5", it's very good, they do the same thing in 6", prior to that used a Skil 5" which was good for the money, it's still going but I needed one in 110Volt and the Metabo is much nicer to use.

Skil is an el cheapo brand for Bosch these days, when I needed to replace the velcro backing pad I got a Bosch one off ebay.

The self-contained dust collection on the Metabo actually works reasonably well, that on the Skil is pretty ineffective. Much better to hook up to a vacuum line if you've got a lot to do, though.

 

Flap discs are good for smoothing rough edges of steel etc., less good for paint removal. Consider some sort of scabbler or a Perago tipped wheel system.

 

Tim

[TandC]

Right ho - so that's roughly the size everyone uses... i shall have a butchers and see what I can pick up for a decent price.

 

Bloody typical - been waiting for the weather to improve for weeks now, and sod's law, with the sun predicted to come out next week, I am back to work.... hey ho! Evening sanding here I come....

 

Thanks for your help. I'll do a thread on it once I get started as I intend on repainting the whole lot, once SWMBO has decided on the colour!

[alan_fincher]

I think this is probably what we have......

 

Sealey Random Orbital Sander

 

(although I seem to recall it cost us a fair bit more!).

Seems to do a good job, and I'd judge rather upmarket of most B&Q/Wickes/Toolstation type offerings, although I could be wrong.

Edited to add:

 

These are definitely for rubbing down existing or new paint - they are not a serious option for completely removing old paint back to bare metal, IMO - far too slow, and would use too many consumables. We found an angle grinder with carbide discs was the way to go for taking it all off.

Edited July 3, 2013 by alan_fincher

[bizzard]

I think this is probably what we have......

 

Sealey Random Orbital Sander

 

(although I seem to recall it cost us a fair bit more!).

 

Seems to do a good job, and I'd judge rather upmarket of most B&Q/Wickes/Toolstation type offerings, although I could be wrong.

 

Edited to add:

 

These are definitely for rubbing down existing or new paint - they are not a serious option for completely removing old paint back to bare metal, IMO - far too slow, and would use too many consumables. We found an angle grinder with carbide discs was the way to go for taking it all off.

I have the earlier Sealey model which cost around £120 trade 20 years ago and is still going strong and in my opinion are the the next best machines to an industrial air operated sander. The cheap ones might be ok for small jobs but generally just make a hell of a buzzing noise without a great deal of sanding.

[pete.i]

Hi all

 

Can somebody PLEASE explain to me what the hell a scabbler is. I know what a Perago tipped wheel is but I have scoured the suppliers up this neck of the woods and no-one seems to know what a scabbler is. My boat roof is covered in what I think is car filler. Apparently the guy who built it didn't like the fact that he could see the roof support struts outline in the right light so he covered it with filler to smooth it out. It did work well and has lasted thirty odd years to be fair but it is now detoriorated to the point where it has to come off. I have taken most of it to be honest using a twisted wire brush in an angle grinder but I was advised to use a scabbler but no-one up here in t' north seems to know what one is and neither did Google the last time I look

 

Cheers

 

Pete

[ChimneyChain]

I've bought a deltalyo das6 from amazon a month back at £79.00. Seems well made, strong and sturdy. Rub part of the boat down and Seems to be fine, but still got 120ft to go so can't give a Definite answer to its Reliability.

 

Darren

[darbon]

I personally use a 4" grinder with a paint/rust removal head, they're about £7-8 from screwfix. They'll cut through paint way quicker than sanding discs, but do wear out quickly.

 

I'm in a similar situation where i'm about to remove all the paint from my NB, i'm probably going to grit blast the whole lot to be honest, it gives the best surface for paint as well!

 

D

[IDS]

I hired a rotary scabbler from a Hire Shop in Northampton for doing my roof, and it did a great job.

Looks like this:-

http://www.refina-uk.com/acatalog/Plasterers_Surface_Scabblers.html

Hire cost was about £40 for the day, which proved to be ample time. Do all your prep removing vents etc from the roof before you hire.

Beware, you need quite a lot of 110v power, either a big 110 v transformer if you have a good mains supply or I used a 2.5 Kw Generator on the towpath. Finish of with an open weave "clean & strip" disc , or a flap disc in a grinder. Use wire cup brushes for hard to get to corners.

[matty40s]

Hi all

 

Can somebody PLEASE explain to me what the hell a scabbler is. I know what a Perago tipped wheel is but I have scoured the suppliers up this neck of the woods and no-one seems to know what a scabbler is. My boat roof is covered in what I think is car filler. Apparently the guy who built it didn't like the fact that he could see the roof support struts outline in the right light so he covered it with filler to smooth it out. It did work well and has lasted thirty odd years to be fair but it is now detoriorated to the point where it has to come off. I have taken most of it to be honest using a twisted wire brush in an angle grinder but I was advised to use a scabbler but no-one up here in t' north seems to know what one is and neither did Google the last time I look

 

a scabbler is a machine from hell.

think angle grinder with a disc formed of many rotating mini serrated - scraping wheels which usually need to be replaced after each boat job.

The scabblers are on hire from toolstation and similar, the wheels need to be purchased as they are disposables.

It makes simple work of large surfaces, however, will not get into corners or non removed window edges without ruining the surrounds, this will need your conventional grinder, sander, wire brush etc, or (remove windows.)

If you suffer from vibration conditions,not wise to use, if you don't, you will do soon.

[peterboat]

I think this is probably what we have......

 

Sealey Random Orbital Sander

 

(although I seem to recall it cost us a fair bit more!).

 

Seems to do a good job, and I'd judge rather upmarket of most B&Q/Wickes/Toolstation type offerings, although I could be wrong.

 

Edited to add: hi having spent the last week using the above beast i can say they are the dbs this is my second one the first went for a swim and was never the same afterwards. i have been using 40 grit to remove rust/paint and 240 grit to flat it where paint surface was ok

 

These are definitely for rubbing down existing or new paint - they are not a serious option for completely removing old paint back to bare metal, IMO - far too slow, and would use too many consumables. We found an angle grinder with carbide discs was the way to go for taking it all off.

Not sure about this as you can easily scar the metal

 

Peter

Hi above post cocked up!! somethink is on the blink might be me anyway the sealey is very good paid about 160 a year or to ago

 

peter

[TandC]

Excellent thanks - looking on flea bay, the newer model Sealey is available with what looks like a more ergonimic handle for under £70

 

http://www.ebay.co.uk/itm/DAS151-SEALEY-150MM-RANDOM-ORBITAL-DA-SANDER-VARIABLE-SPEED-750W-230V-/281110241017?pt=UK_Home_Garden_PowerTools_SM&hash=item417379def9

 

That, coupled with my drill/grinder using wire brush attachments/flap wheel and the smaller detail sander for the hard-to-reach bits, should provide the necessary tools for the task.

 

The yard quoted £300 to shot-blast the roof/gunnels, and I am hoping he'll do the awkward bicycle rack on the back too, which is made of that steel chequer-plate stuff. That i think is money worth spending to tackle the worst bits and give me the best surface for the roof, which gets the most wear (our mooring is under two full Ash trees, plus has resident ducks with bowel problems....)

 

So the plan is to sand the sides, then take the roof vents and gas flue chimney off. I think taking the stove chimney boss off is a step too far. The mushroom vents are going to be a nightmare I am sure, with old brass slottted head screws fitted 50 years ago, so I can forsee having to drill those out.

 

Then, once the sides etc are done, vents off, I shall cruise up and have the roof done.

 

As far as painting is concerned, it's going to have to be done in the open, so I was planning on doing the first 4 coats myself and then seeing if I could get in to the paint tent to do the final coat.

 

Now, what colour....?!

 

Thanks for advice all.

[Grace and Favour]

 

Now, what colour....?!

 

Thanks for advice all.

It would be unwise to paint it camouflage greens/browns

[ditchcrawler]

I hope you are prepared for all the mess you get from blasting. Its one thing to do the hull below waterline, but when you get to the roof with opening then a lot of muck will enter the boat

[talisman]

I always strip paint with a scabbler. I can strip a 50 foot boat in less than 2 days. Then its time for the orbital or angle grinder to finish off. I hire from Brandons at £30.00 a week.

[BEngo]

<SNIP>

The yard quoted £300 to shot-blast the roof/gunnels, and I am hoping he'll do the awkward bicycle rack on the back too, which is made of that steel chequer-plate stuff. That i think is money worth spending to tackle the worst bits and give me the best surface for the roof, which gets the most wear (our mooring is under two full Ash trees, plus has resident ducks with bowel problems....)

 

So the plan is to sand the sides, then take the roof vents and gas flue chimney off. I think taking the stove chimney boss off is a step too far. The mushroom vents are going to be a nightmare I am sure, with old brass slottted head screws fitted 50 years ago, so I can forsee having to drill those out.

 

Then, once the sides etc are done, vents off, I shall cruise up and have the roof done.

 

As far as painting is concerned, it's going to have to be done in the open, so I was planning on doing the first 4 coats myself and then seeing if I could get in to the paint tent to do the final coat.

 

Now, what colour....?!

 

Thanks for advice all.

Be very careful of shot blasting the roof. They are usually quite thin and shot blasting compresses the surface of the metal to some extent. If the yard are over enthusiastic with either the blast medium or the blast pressure the roof WILL change shape...

 

Be prepared for a lot of mess internally.

 

N

[TandC]

Talisman - you mention a scabbler.... what sort of finish does this leave? Is it not very aggressive, leaving lots of scoring? I have seen on here some interesting threads concerning a Surface Blaster - essentially an angle grinder motor (albeit maybe a lower RPM) with seven rubber disks, each covered with tungsten 'bullet' tips which spin independently, giving the finish similar to shot blasting. the benefit to me seems to be that with the guard fitted, there is the means to extract dust and paint, making it less messy. At £50 hire for a full weekend, that's a saving over shot blasting, and i could probably do it here on the mooring, saving me the 6 hrs to the yard

 

But as we've still not nailed down a paint colour, there is no motivation to do it!

 

Anyone else with experience of doing it yourselves with a scabbler or surface blaster? I'd love to see the finished results....

[leolady too]

The paint we took off our roof had grit in (or between layers of) it. I mean grit, not sand. I tried a number of methods but settled on nitromors. Two gallon cans (about £50 for the two then) did the whole roof (62 ft boat). There was some light sanding afterwards but it really made the job very easy and not expensive compared to scabbler hire. I'd put in a word for Abranet abrasive sheets and a vacuum attached to the ROS. Abranet is expensive but lasts well and with the vacuum it leaves almost no dust. Wipe with panel wipe and you're done.

[bizzard]

A wire cup brush in an angle grinder is pretty quick, a lot cheaper if you already have an angle grinder and it will not score or gouge the steelwork.

[TandC]

Thanks Bizzard - I do have one, although its for my small grinder, so is only about 3inches in diameter and I can imagine would take a while, plus has no effective means of attaching dust extraction..... I was planning on using that for the tight areas where the surface blaster or scabbler cannot reach.

 

http://www.brandontoolhire.co.uk/en/decorating-tool-hire/142-surface-blaster.html

 

This is the Refina surfance blaster I had been considering. Will also need the 110v transformer, although I think I have one of those somewhere.

 

Anyone used one of these with successful results? I need to go to bare metal on gunnels and roof. Can likely just sand the sides, but I may just go the whole hog.

[fudd]

Hello all.

 

Quick question for anyone with experience of preparing their boat for exterior re-painting:

 

 

The roof is badly pitted with two previous coats of badly applied paint flaking off and I've been advised by the boatyard that it will be best to shot-blast the roof and gunnels, whereas the sides are not as bad and can be sanded.

 

Any advice on which Random Orbital Sander works best - is it best to use a normal sized machine - 150mm sanding area - or are there larger, more industrial machines which could cut down the time?

 

I'm expecting to spend a bit more on decent sanding discs (Abranet for instance) and will use a dust extractor.

 

Quick search turns up a number of similar machines in that sort of size, but I havent seen anything particularly larger. While only 45ft long, as always, I am keen to invest in decent tool to make the job quicker and easier so grateful for any advice.

 

Thanks,

 

T

 

I've got a Festool sander. Very good but what makes it even better is a dust extractor. It keeps the pads cool and doesn't clog and they last so much longer. I don't expect you would want to pay upwards of a 'monkey' for a set up but even a Hoover would do. And it stops the swans from going the same colour as your boat. The extractor is as important as the sander in my opinion.

Steve P

 

Edited to say Tim Leech said it first.

Edited July 31, 2013 by fudd

[bizzard]

If you haven't a dust extractor wear a small face mask and try and stay upwind of the machine whilst sanding.

[TandC]

I've a Record Power 'can' type which I use on the lathe so that will be pressed into service, hoping that the filter is up to the job.