what is sanding?

[vtpcnk]

sorry if this is a basic question. but i gotta know.

likewise what is 'scraping' in the context of tru oil finish?

there's this url which gives the steps for a truoil finish : http://www.lmii.com/CartTwo/TruOil.htm

what is the difference between truoil finish and sealer?

how important is it to fill the "pores"? why is this done?

in the context of sanding something called "steel wool" is mentioned. is this some metallic wool kinda thing and will rubbing this on a guitar body or neck, cause the latter to be scratched? are you supposed to rub it hard or gentle?

likewise with "sanding sheets".

also mentioned is 3M Scotchbright finishing pad as an alternative for steel wool. which is the better choice for a beginner like me?

 

[boaty]

If you have a very porous wood (like mahogany or red oak), it will soak up the finish forever like a big sponge.  The wood will be conditioned, but it won't be protected by a layer of finish.  By sealing the wood with sealer, you prevent the wood from soaking up the oil entirely, and you get a build up of finish on the surface of the wood.  You can really feel the grain on mahogany necks that aren't fully sealed before taking a finish.

It's my opinion that hard, closed grain woods like maple don't need to be sealed when you're applying an oil finish.  If anything, you should actually cut the oil with the proper thinner so that the oil stands a better chance of being absorbed into the wood.  The goal is to find the right middle ground where the finish isn't entirely in the wood but isn't entirely on the surface of the wood either.

I've worked with linseed oil and tung oil, but I don't know what "tru-oil" really is.  They describe it as "a polymerized linseed oil with other natural oils added".  "Natural oil" can mean a lot of things.

They also suggest that boiled linseed oil won't build up a finish.  This isn't always correct.  It depends on the wood, and it depends on how durable a finish you want.  Boiled linseed oil will build up on a wood like maple or on a wood that's already very oily like rosewood.  It won't be hard at all though, although it does provide some protection from moisture.

If it's a hard wood like maple, also be careful about over sanding before the first coat goes on.  You can actually make the wood resistant to a finish that way.

When sanding, you shouldn't use much force.

I would avoid steel wool since bits of the wool can get stuck in the finish, and paper does the job just fine.

 

[vtpcnk]

so a sealer should be applied first? and then the coats of oil?

and you still haven't explained what sanding is and why we should do it?

 

[boaty]

so a sealer should be applied first? and then the coats of oil?

It depends.

and you still haven't explained what sanding is and why we should do it?

Yeah, it's one of those things everyone knows already so I didn't think to explain it.  My bad.

 

[Rick]

Between coats I don't sand.  More like scuffing with an extremely soft finishing sponge say, for the first few coats and then, a light swipe with a paper towel in lieu of sanding.  It all depends on your touch.

 

[Alfang]

When you ask, "What is sanding?" are you saying you dont know what sandpaper is?  It's an abrasive paper to grind down a surface

 

[vtpcnk]

>When you ask, "What is sanding?" are you saying you dont know what sandpaper is?  It's an abrasive paper to grind down a surface

right i have seen my carpenter use this. but why do you need it in between coats? wouldn't that take the coat off?

 

[m4rk0]

Are you taking the piss??  :tard:


you should use 0000 steelwool to sand out the finish between coats, so you will get nice even layers with no streaks, bubbles, etc.


Seriously, are you taking the piss??

 

[mayfly]

Seriously, are you taking the piss??

I was wondering that as well - and I was also admiring the restraint of forum members in answering the question.

BTW, another reason why you would sand between coats is to level the finish (remove drips/orangepeel, etc) before the next coat.  Some folks do this, other's don't.  I'm starting to fall into the latter category.

 

[vtpcnk]

>Seriously, are you taking the piss??

hey, i have never done this before man. so i am not sure what is involved.

just trying to get as much specific information as possible before i do it, that is all.

 

[ByteFrenzy]

>When you ask, "What is sanding?" are you saying you dont know what sandpaper is?  It's an abrasive paper to grind down a surface

right i have seen my carpenter use this. but why do you need it in between coats? wouldn't that take the coat off?

How much you take off depends on how coarse or fine the sandpaper is. That is indicated by the number printed on the back. 80 is pretty coarse and 600 or 1200 is very fine. Coarse sandpaper will remove a lot of material quickly but leave a very rough surface. Fine paper will leave a smooth surface but only removes just a small bit of material at a time. So the trick is to choose a 'grit' (= describig how coarse sandpaper is) that will remove just the amount of material you need to, and does not leave the surface any rougher than need be.

When you're sanding between coats you just want to remove a thin layer from the top of the coat, and leave a finish that is smoother than the coat was. In that way you'll be working towards having a smoother and more regular finish with each coat. For this purpose you'll also want to wet sand - put some mineral spirits in a flat tray and dip the sandpaper into it every now and then.

I would suggest that you try to just read through as many threads about finishing as you can. A lot has already been said and it's all free for the taking. There is very complete reference material in the stickies. Your question may have been a bit too elemental. You need to learn to walk before you can run, and your question was a lot like asking what a shoe is for on a board dedicated to marathon running.

 

[exalted]

I would recommend starting out small. Buy a junky dining room table at a garage sale for 10 bucks, and try re-finishing that. Work your way up to the $300 guitar body. 

I tried to dive in head first, and I was quickly overwhelmed.

 

[blue313]

Buy a junky dining room table at a garage sale for 10 bucks, and try re-finishing that. Work your way up to the $300 guitar body.

Definitely. 

If you've never sanded anything before start with a chair, table, scrap wood etc.  You're bound to make mistakes your first time out.  Have no fear, it's not rocket science but it does take some practice.  That practice is worth 1000 internet searches.

 

[ByteFrenzy]

Buy a junky dining room table at a garage sale for 10 bucks, and try re-finishing that. Work your way up to the $300 guitar body.

Definitely. 

If you've never sanded anything before start with a chair, table, scrap wood etc.   You're bound to make mistakes your first time out.   Have no fear, it's not rocket science but it does take some practice.  That practice is worth 1000 internet searches.

Yeah. There are heaps of little silly details. Sometimes you want to make little circular motions with very little pressure, and at other times it's imperative to only sand with the grain, not across. That's all experience and while you can build that up very quickly you should practice on something of little value. Refinishing your dad's old '61 strat is NOT a good first project.

 

[Alfang]

This has to be a joke, can we move beyond sandpaper and discuss how to push the top of a spray can, everytime I push the top of the spreay can, paint comes out, what gives? How can I take advantage of this ?

 

[jay4321]

This has to be a joke, can we move beyond sandpaper and discuss how to push the top of a spray can, everytime I push the top of the spreay can, paint comes out, what gives? How can I take advantage of this ?

Yeah after reading the posts and some of the other threads I'm beginning to wonder. I'm a total finishing novice myself, but come on...

If these are serious questions in your threads, I'd recommend getting one of the popular videos and books on finishing and starting with that. Even if you're not experienced with finishing, knowing what sanding actually IS should be a given. I mean it's like you want to make scrambled eggs, but don't know what "frying" is.

 

[boaty]

More like not knowing what eggs are.

 

[edwing206]

This is sanding
http://www.youtube.com/watch?v=TXOgmZ9Et6A

 

[rahimiiii]

If you don't know what sanding is then you probably shouldn't be working with tools.

 

[Rick]

This is just an observational comment, not judgemental but I think what's going on is that, like a lot of kids these days, the poster never had a shop class, never had to help his dad work with wood and has no experience working with his hands.

The kids just plop down, turn on the video games, surf the net (and there's nothing these things) but like was said elsewhere, it's virtual experience of life, not real.