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Metal Head
15th April 2007, 04:48 PM
Hi,

I have been getting a bit frustrated with the preparation I have been doing for a lot of the weatheboards (existing) on our house. I have been using a circular orbital sander as well as one with a triangular shaped head. However, sanding (using the latter) it appears that the edges of the sanding sheet wears away very quickly because of having to get into all the nooks & crannies:- . I did purchase a packet of white colour ones (made by Bosch - 40 grit) that claim to last 4 times longer than their normal sheet, but as yet they haven't lasted even twice as long:((. I also seal most of the gaps with Selleys "No More Gaps" - is this the way to go?.

I also for the first time bought a "squeeze ezy" tube of "no more gaps". But given that it was nearly half as much again than the conventional cartridge is there anything to be gained by going down this avenue?

Once I have finished off the preperation, I normally put on a undercoat and then lightly sand it with 240 grit - is this too coarse for the task?

Is there any other tips that you can suggest (other than spraying & getting somene else to do it) that makes this type of work easier?.

Thanking those in advance who are kind enough to share their advice with us:wink:.

Regards
MH

Sturdee
15th April 2007, 05:00 PM
Is there any other tips that you can suggest (other than spraying & getting somene else to do it) that makes this type of work easier?.


Yes, don't sand the weatherboards. :D

On my house, which is all rounded weatherboards, I wash and wipe the walls prior to painting and seal any cracks with a gap filler but I don't sand them. Sanding may make them look better but life's too short for spending a month to sand back our house.

BTW don't use that squeeze pack but use a cartidge gun. In between use I insert an old metal bbq skewer into the nozzle to stop it going of, but a 50mm nail will also do the trick.


Peter.

Metal Head
15th April 2007, 06:00 PM
Yes, don't sand the weatherboards. :D

On my house, which is all rounded weatherboards, I wash and wipe the walls prior to painting and seal any cracks with a gap filler but I don't sand them. Sanding may make them look better but life's too short for spending a month to sand back our house.

BTW don't use that squeeze pack but use a cartidge gun. In between use I insert an old metal bbq skewer into the nozzle to stop it going of, but a 50mm nail will also do the trick.

Peter.

Thanks for the advice Peter. However, I beg to differ in only washing the boards down. I now it is a thankless task but I feel that it is no good me spending good money (and time) on paint that won't last that long unless it has a solid base to stick to.

Btw, is a finger belt sander a better proproposition than the 2 type of sanders I have used so far?.

Regards
MH

Sturdee
15th April 2007, 06:14 PM
Btw, is a finger belt sander a better proposition than the 2 type of sanders I have used so far?.



No, they're not.

They won't get into a corner like the triangular shaped head one you're using and they are much more agressive than other sanders. They quickly will sand a grove in your boards.

I use mine mainly to avoid chiselling as it will quickly make or enlarge an existing opening. Especially handy for making the hole in a door frame to house the locking bolts.

Peter.

OBBob
15th April 2007, 06:28 PM
Hi Metal Head.

I've been there a few times ... its a horrible job but it really does look good when you get to the end. If its an old house one of the best things i found was to go with a low sheen paint, that makes a huge difference to how many of the imperfections can be seen from a distance.

My last one was pretty bad ... lots of flaking paint, so I actually used an angle grinder with a fairly harsh sanding pad on it. If use lightly it worked really well ... just have to be careful becase it will go right into the baords if you aren't light.

Sorry ... can't help much more. I actually swore that if I ever had a wall that bad too do again ... I'd just allow for all new weatherboards in the budget.

durwood
15th April 2007, 07:40 PM
I'm with Sturdee, there is no need to sand the boards
::Unless
there is lousy paint which has cracked or is otherwise not a sound foundation
Or the boards have been painted more than three times before.

If the paint is sound wash it off and paint again. There is no reason to believe your new paint would last any longer if you removed the old paint by sanding it. Not only would the surface require more extensive preparation but the end result may be worse than just painting onto a sound previously painted surface.

Best method to remove paint from timber is to burn off the paint.

Using an open flame is these days frowned upon but there are several other safer ways.

A good heat gun will usually blister the paint so you can scrape off the old paint. Or there is available heating lamps set -ups which do a larger area. Any bar heater would work, if you have one try a section and compare it to your sanding method I would think it would be quicker.

Depending on the paint on the boards will depend on the results you get. Modern acrylics are very rubbery and clog the paper quickly. If there is any oil based paint ( enamel ) underneath heat will blister is real quick and it will be easy to scrape back to bare timber. Gets into the corners quicker.

I personally always use a LPG torch but several members on the forum consider this a no-no. I won't recommend you use one but I would have no hesitation using an open flame as I have never had a problem with it in 40 plus years.

If you have access to a heat gun/ infra red heat lamp try it out it should be a lot quicker and miles cheaper than buying sanding paper.

Metal Head
15th April 2007, 10:37 PM
There is no reason to believe your new paint would last any longer if you removed the old paint by sanding it. Not only would the surface require more extensive preparation but the end result may be worse than just painting onto a sound previously painted surface.

Thanks Durwood for your advice:2tsup:. I'm sorry but it appears i haven't made myself understood correctly which isn't hard being a former Brummie:U. I have only sanded (and filled where required) the areas where the paint was loose or had already. Given the ground movement under our house quite a few of the weatherboards have moved resulting in the gap filler put on by the previous owner has stretched under the bull nosed edge. Thus I have used the 2 sanders (as mentioned previously) and a chisel for removing this and the loose paint.

Best method to remove paint from timber is to burn off the paint.

I remember my Dad (for nearly 30 years) having to use a little burner (which were common in Britain) with either parrafin or meths as it's fuel. He spent many 100's of hours over the years having to get up the ladders to burn off the enamel paint on the window frames and the ledges. But 20 years ago he had all the wooden bits (including the doors) replaced with PVC which is extremely popular there. Not many wooden frames are used in modern houses now. Do you know why it has never taken off here in australia - I presume the climate plays a big part in the reason:?.

Using an open flame is these days frowned upon but there are several other safer ways.

A good heat gun will usually blister the paint so you can scrape off the old paint. Or there is available heating lamps set -ups which do a larger area. Any bar heater would work, if you have one try a section and compare it to your sanding method I would think it would be quicker.

Depending on the paint on the boards will depend on the results you get. Modern acrylics are very rubbery and clog the paper quickly. If there is any oil based paint ( enamel ) underneath heat will blister is real quick and it will be easy to scrape back to bare timber. Gets into the corners quicker.

I personally always use a LPG torch but several members on the forum consider this a no-no. I won't recommend you use one but I would have no hesitation using an open flame as I have never had a problem with it in 40 plus years.

If you have access to a heat gun/ infra red heat lamp try it out it should be a lot quicker and miles cheaper than buying sanding paper.

I can get access to to an heat gun via work which I will use next time I have to paint some of the boards. If it doesn't work I might just replace the buggers.

Cheers
MH

manoftalent
15th April 2007, 10:59 PM
MetalHead ...what your going through is just one of the reasons I hate painting.....or anything to do with it ..good luck mate:2tsup:

durwood
16th April 2007, 01:12 PM
You are right about the weather, PVC only lasts a short time in our sunlight.

If you have ever seen PVC guttereing or weatherboards after a hail storm you will know why its not used much. Looks like the vandals have been at it with a hammer.

Just noticed you mentioned using "No more Gaps" check the label from memory its only suitable for interior use. I have some "uni-fix" gap sealer which is supposed to be suitable for exterior use but it states "Not suitable for use between tongue and groove boards or weatherboards."

Your dad was probably using a "blow torch" which was the way it was done before LPG became available.

Metal Head
16th April 2007, 01:52 PM
You are right about the weather, PVC only lasts a short time in our sunlight.

Thanks for confirming that:2tsup:

If you have ever seen PVC guttereing or weatherboards after a hail storm you will know why its not used much. Looks like the vandals have been at it with a hammer.

Just noticed you mentioned using "No more Gaps" check the label from memory its only suitable for interior use.

Thanks for the news after I have done 50% of the boards:o :doh::D . I'll have to check that out when I get home tonight - I should have read the label but I trustingly asked a Bunnings assistant (who was working in the paint section at the time) what was the best stuff to use and he showed me the stuff on the shelf.

I have some "uni-fix" gap sealer which is supposed to be suitable for exterior use but it states "Not suitable for use between tongue and groove boards or weatherboards."

Your dad was probably using a "blow torch" which was the way it was done before LPG became available.

That's right Durwood they were known as blow torches but I haven't seen one for years.

Gumby
16th April 2007, 02:14 PM
Metal, I don't know about others and i don't want to sound picky but trying to read your posts when you enclose everything inside the quote box is very confusing, even with the different colour. can I make a suggestion that you do it like this........



You are right about the weather, PVC only lasts a short time in our sunlight.



Thanks for confirming that



Just noticed you mentioned using "No more Gaps" check the label from memory its only suitable for interior use. I have some "uni-fix" gap sealer which is supposed to be suitable for exterior use but it states "Not suitable for use between tongue and groove boards or weatherboards."
Thanks for the news after I have done 50% of the boards:o :doh::D . I'll have to check that out when I get home tonight - I should have read the label but I trustingly asked a Bunnings assistant (who was working in the paint section at the time) what was the best stuff to use and he showed me the stuff on the shelf.



I have some "uni-fix" gap sealer which is supposed to be suitable for exterior use but it states "Not suitable for use between tongue and groove boards or weatherboards."

Your dad was probably using a "blow torch" which was the way it was done before LPG became available.


That's right Durwood they were known as blow torches but I haven't seen one for years.


I'm just trying to be constructive here.:wink:

:)

sinjin
2nd May 2007, 10:05 AM
The issue about sandpaper comes down to cost. The paper i use is very expensive. But is lasts like no other i have used and is made by a West German company called VSM is it zirconia diamond based so hence the expense. Also the backing material is cloth. The backing amongst other issue is what holds the abrasives together. Cheap backing generally shorter life. As for clogging this cloth backed paper seems very good.
As for gapes i use Sikaflex 15LM. this product allow for quite a bit of expansion. But you need to be neat and tidy when using it. Mask the joint squeese in the sealant then trowel the joint flat then remove the tape.
15 Lm doesn't sand al that well but has great expansion/contraction abilty.
If you have a gap say up to 2-3mm then sika is good choice. if there is a tiny gap then Sika is a poor choice. You need a gap to allow the product to expand and contract. Example is say the gap is only 2-3 mm wide and the sealant allows for 15% movement before it fails you can see you still have very little movement.
I have just about every sander you can possibly buy regardless of expense. I was a boatbuilder and anyone who has had the missfortune of sanding the under side of yachts will agree you simply want to be doing that job as shorter time as possible so any machine that could speed the job up the a good choice.
Having said that i personally found for me at least when i sanded down my own home it was faster to use a 1/3 sheet Festo machine. It had the advantage of being able to follow the curves of the bent boards without trying to flatten them off all the time. This coupled with the VSM paper was for me the go.

Metal Head
2nd May 2007, 12:34 PM
i don't want to sound picky

Sorry Gumby that I had overlooked your post.

I am not a know all and I am willing to learn new things unless it is off members with a name starting with a

"G":(( & finishes with a "Y":((

Look Below:wink:

















































No offence taken here G :D :D :D y - too thick skinned especially around the waist:(.

Theremin
10th May 2007, 11:19 PM
Thanks for the news after I have done 50% of the boards:o :doh::D . I'll have to check that out when I get home tonight - I should have read the label but I trustingly asked a Bunnings assistant (who was working in the paint section at the time) what was the best stuff to use and he showed me the stuff on the shelf.



You can get a Selleys gap filler specifically for weatherboards. See here: http://www.selleys.com.au/Selleys-No-More-Gaps-Weatherboard/default.aspx

totoblue
16th May 2007, 04:14 PM
Here's my bottled experience:

If I need to take the old paint off, I use an electric heat gun. Usually 90% of the paint comes off in sheets the size of your hand. A lot less messy than sanding, and faster, and better, and cheaper as you don't need to replace the sandpaper when it gets clogged.

I use that Selley's weatherboard filler. But you need tons of the stuff (not a problem with the filler, just the nature of the problem). I also use Nordsco Super Filler which is grey, easily tooled to a smooth finish, and slightly flexible (good for nail holes etc). It's also easily sanded, unlike most fillers which are flexible to any degree.

A quick sand of old paint is good to help the new paint stick. Wash it as well. If you have the water to spare, use liquid sugar soap (needs a very good rinse), otherwise just use one of those bathroom cleaning cloths and a bucket of water.

Always use an undercoat, even on previously painted boards.

If you use a tinted undercoat, you can get away with two top coats otherwise you may need three.

I use Dulux Weathershield as a top coat. We wanted something between Gloss and Flat, so we mix them (Dulux help line said that was ok to do if you stir the mix frequently).

We had been using the Dulux buff coloured undercoat, but have just recently switched to using Dimensions undercoat tinted to the same colour as the top-coat. Dimensions is from 3D paint stores and is white and thus tintable. It is made by Dulux and is suitable as an undercoat according to 3D paint store staff. Bristol have a tintable exterior undercoat as well.

Use good brushes. We use Monarch Advance, which are expensive but they give a better finish, last longer and are easier to clean.

If you need to replace weatherboards, you'll probably want to predrill nail holes. I had a problem with drill bits getting hot and spinning in the chuck (our house hardwood frame is as hard as buggery). Solved that partly with hex shank drill bit but drill bit still gets hot and thus clogged. Recently bought hex shank drill bits for wood and they don't get clogged. It took me a while to realize to use wood bits for wood but I got there! Never had a 2mm wood drill bit before, but that B-place has hex shank wood drill bit sets for $10 in suitable sizes for nailing.

LotteBum
18th May 2007, 09:46 AM
I've recently done this as well. Paint was flaking and in generally horrible condition. Here's what we did:

Used an angle grinder with a harsh sanding pad.

The angle grinder wouldn't do the corners - use one of those corner sanders with the harshest paper you can get for that.

When we had removed all paint, we washed the hell out of the wall and gave it a coat of primer/sealer (we used a 2 in 1 or something along those lines).

Paint to your heart's content. We used a low sheen - as mentioned earlier, using a low sheen paint means imperfections don't stand out as much. Besides, I prefer the look of the low sheen.

Sure, it was a prick of a job, but it looks fantastic now.

Cheers,
Lotte