PDA

View Full Version : Newbie sanding confusion















Mnb
2nd June 2017, 07:34 PM
Hi everyone. I'm Mary from the Dandenongs outside Melbourne.

I started woodworking two years ago but had a break of about 3 months and for the last 7 or 8 months I have been stopping and starting because of illness. (Two root canals during which I was up and down. I was still sick and insisted on both being removed to find an abscess at the top of one. That was two months ago and I'm still not better. Going to lots of specialists etc. Sorry, it's driving me crazy)

I haven't learnt two years worth of knowledge is the point. I started from absolutely no idea of square or saws or how to use a power drill. I have an Ozito table saw and router I was given and have bought a Ryobi random orbit sander. After a lot of learning about the basics I started making mitred boxes. I was so focused on the box bit that I didn't do any finish sanding or finishing at first and it has lagged behind my box skill.
------------------

So. The question is; I don't seem to get the same results with the random orbit sander as I can by hand sanding. Is that normal?

And; I read things that say -
mark/draw on the surface with a pencil and you have sanded enough at that grit when it's gone (haven't found that)
Scratches are invisible to the eye after 180 grit blah blah (haven't found that)
The Ytube videos seem to have people just sanding up the grits (fairly briefly) with a ROS and that's that, but even after eliminating many problems and mistakes with my sanding I don't get the results I want that way

How good do many people aim to get the wood?

Possibly
(I think it's going to vary. The boxes I have made are fairly small and a scratch the same size will look bigger on a smaller pieces.)

Christos
3rd June 2017, 07:34 AM
Welcome to the forum.

I think you will find that not everyone enjoys sanding and I am only guessing that the youtube videos are brief because of that or they have been edited. Who wants to watch people sanding, I think it is comparable to watching paint dry.

I can not comment on the ROS as I don't own one as all my sanding on flat surfaces is done by hand. I normally sand with the following grits, 120, 180, 240, 320 and I might go a little higher to 400 but that is not very common for me. You can add more grits between the 120 and 320 but for me it does not suit doing that.

There are of course rougher grits of 80 and it you start with this the scratches are normally noticeable by the eye. You will need to spend more time on the 120 to remove the scratches from the 80 grit. I don't discount this grit from my shed it is just not used on flat work very often if at all. I have used it on pieces that I had turned on the lathe but that's a whole different story.

To use a pencil as an indication of where you have sanded and what needs to still be sanded is not a bad thing. You basically hold the pencil lightly on the end and rub this over the surface. No need to press down on the surface as you will be giving yourself more work to remove the pencil lines.

My aim for the surface of the wood is to get this as smooth as I possibly can. Once the finish is applied it makes it very difficult to remove scratches as you basically have to remove the finish and start sanding again.:no:

You might find that on some occasion it would be nice to raise the grain before the final sanding grit. I have used a spray bottle filled with water or sanding sealer when turning a piece on the lathe. I spray the surface with a mist of water and once this has dried I will sand the surface again at the last grit used for me it would normally be 240grit.

Rod Gilbert
3rd June 2017, 09:00 AM
Hi Mary welcome to the forum,
Sanding is I my opinion the least enjoyable part to wood working but it is a necessary chore and needs the same dedication as any other aspect of the job the use of pencil as an indicator is simply to show you have covered the whole area with the current grit (something that becomes second nature after a bit of experience) it's removal doesn't mean all the scratches from the previous grit have been removed. You should not go to the next grit until all deeper scratch marks from previous courser grit are removed then each subsequent grit only has to remove the marks of the last pass. Each time you change grit you should only be sanding marks from the last pass, you will never remove a sanding mark left from a 120 pass with 240 or higher you have to go back to 180 and remove before going up.(hope this makes some sense)
Regards Rod.

LGS
3rd June 2017, 09:26 AM
Hi Mary,

Welcome to the forums. I don't have a problem sanding at all. The reward is seeing and feeling the change in the timber, prior to finishing with you choice of Oil or Shellac or any other finish you desire.

You can try my sanding regimen which can be found at Damn Fine Furniture (http://www.damnfinefurniture.net). Here you will see a method for oiling timber and, more imoportantly, a sanding protocol. The sanding method can be used with most finishes as you can stop anywhere you are happy with the smoothness and lack of scratches. You can have a look at it and see how you go with just the grits up to and including the 400g. (before adding the finish itself. If you find this isn't working for you, I am happy to visit and set the system up for you. You can send me a PM (personal Message) which you shall be able to use once you receive your confirmation.

Regards,

Rob

cava
3rd June 2017, 11:11 AM
If you find this isn't working for you, I am happy to visit and set the system up for you. You can send me a PM (personal Message) which you shall be able to use once you receive your confirmation.


This is what I like about this forum.

Kudos Rob. :2tsup:

malb
3rd June 2017, 04:53 PM
Lots of good info and offers of help here but one thing that hasn't been mentioned is some surface prep before assembly. Ideally you want to do as much as possible of the preparation before assembly, or even before the final cut to size if possible. And maybe try and get a decent surface on the material before you start sanding, which would involve planing and possibly scraping. Mary hasn't said what timber she is using or where she is sourcing it, but basic dressed all round timber from a green shed or similar is probably not going to to be ready to finish with just a light general sanding, and would need a reasonable amount of prep before hand.

LGS
3rd June 2017, 05:31 PM
It's my standard procedure to prepare all faces of a piece of timber before touching the assembly process. How I do that is unimportant here, you can be assured that it is done. There are other circumstances here which may preclude using hand planes, electrical planes and even scrapers. It's been my experience that my means of surface preparation provides a surface second to none for the next step. There are a number of people both on this forum and not who have used my system and I have had no complaints. None.

Just my two cents.

woodPixel
3rd June 2017, 05:55 PM
LGS's tips on hard burnishing are bang-on. They proved very helpful to me when I was struggling with it. :D

As for normal sanding, I found two things are important - dust extraction and good sandpaper.

Expensive isnt good, but good isnt cheap... the stuff sold at Bunnings is as close to junk as one can get for fine woodworking. The SandPaperMan sells some outstanding product. Try to have a look around and grab a smaller multipack to give it a go.

Also, hook the sander up to a dust vacuum, it will perform much better. The dust clags up the grit and reduces its lifespan and functionality quite considerably.

Luke Maddux
3rd June 2017, 05:59 PM
The simple answer is "Yes, hand sanding gives a better finish". But it's not so simple...

A Random Orbital Sander (ROS) abrades the wood randomly, which means both across and along the grain. It does it so much, so quickly, that it comes very very close to hiding its own sanding marks. It is superior to hand sanding in that it will remove the sanding marks from each previous grit more quickly and efficiently.

But eventually, you reach the desired level of smoothness (often 400 grit for many people) and you are done with the ROS. At this point, if you hand sand along the direction of the grain of the wood, you will improve the visual quality of the finish by even further hiding/disguising the sanding marks left by the ROS.

So hand sanding gives a better finish, but it's a longer road to get there. An efficient approach is to use the ROS to your desired final grit and to then hand sand with the grain with just that grit.

Cheers,
Luke

LGS
3rd June 2017, 06:47 PM
I disagree, Luke, it's possible to sand to 4000 grit quite easily using the right ROS either Festool, or even better Mirka. They use grits a lot higher than our little toys when finishing car duco. If you have a ROS, I suggest you go to a Festool store and invest in some 2000 and 4000 grit pads and see how your finishing comes up. Do it against the hand sanded stuff and time yourself to see which takes less time as well!

Mnb
3rd June 2017, 07:55 PM
Thanks guys. I have had so many problems and thought I had worked things out so many times (sometimes to think I was wrong about the issue and discover that I was right but there was another problem as well) that I am losing perspective.

I didn't sand well enough initially and the deep scratches were still there later.
I used crappy Bunnings sandpaper and made my own scratches.
I sanded on a scratched combination belt/disk sander and created my own scratches.
I started too coarse on surfaced timber and created my own scratches. (I hadn't got it before)
Got impatient and scrubbed at the wood. Yes my own scratches again!
And during all that I wasn't sanding until I finished putting together the bloody boxes.

I have used tassie oak only.

i haven't checked out the links but will.

How do I prep wood? I have no jointer or thicknesser. I did set up a power planer sideways against my bench to get the edge to ninety degrees and then I use the cheap table saw. I sanded 120 with the Ros I have now on the last two and then hand sanded after the box is together. I have been using the wet and dry sandpaper because it seems better but it's expensive. They look reasonable but I am using the surfaced wood which is easier.

A problem with the sander is keeping the wood a consistent thickness is difficult. Maybe I need more practice?

I want to ask more but my brain isn't working so I will leave it at the moment.

Mnb
3rd June 2017, 07:58 PM
Thanks for explaining the pencil thing too. :)

Mnb
3rd June 2017, 08:24 PM
Looked at the sanding regime. I guess going up and back even with a sander is better. The fibres are less likely to be pulled out to the side. I will try and let you know. Thanks.

I did a bit of reading on wood and logically the best thing seems like a scraper because it cuts the fibre at a level. Do you guys use scrapers? I have tried but perhaps didn't sharpen properly because it gave me a few nasty scratches even though most of the surface was good.

Sturdee
3rd June 2017, 11:59 PM
I don't know if in your research you ever saw the TV series " Woodworking Masterclass" by Steve Hay originally shown on Channel 31. In the second series he showed how to make some boxes. Over a number of episodes he goes over the whole process from beginning to end.

If you haven't it is worth looking at the show and here is the link to them (https://www.youtube.com/watch?v=yF40G54cdxw&list=PL_ri-3OoV-Tm06BTuxOBl3UJF4qiZ4rAq).

Peter.

Luke Maddux
4th June 2017, 04:50 AM
I disagree, Luke, it's possible to sand to 4000 grit quite easily using the right ROS either Festool, or even better Mirka. They use grits a lot higher than our little toys when finishing car duco. If you have a ROS, I suggest you go to a Festool store and invest in some 2000 and 4000 grit pads and see how your finishing comes up. Do it against the hand sanded stuff and time yourself to see which takes less time as well!

Which part are you disagreeing with? The parenthetical statement about 400 grit paper being a good stopping point for many people?

The grit to which people sand is just a matter of preference and, beyond a certain point, semantics. Sure, you can sand to 4000 grit with a sander, and it might look (and would certainly feel) better than 400, but if you then take the 4000 grit paper and rub it along the grain, it's going to further improve the finish. The point of my statement was that no matter how far you sand with an orbital, you can further improve the finish by then sanding along the grain with whatever your preferential final grit was on the sander.

Surely you don't disagree with that? That's widely accepted sanding philosophy... right?

LGS
4th June 2017, 10:23 AM
No Luke, would't disagree. Enjoy your sanding and I'll enjoy mine. Really sorry I bothered at all. Won't make the same mistake again.

woodPixel
4th June 2017, 02:09 PM
Who doesn't enjoy sanding! I love it :)

Not long ago, I saw an ad for a job at a local studio. It was for a sanding grunt. Sanding all day, every day. Nothing but sanding from morning till evening.

See? There are entire jobs devoted to what we love. :)

Luke Maddux
4th June 2017, 03:02 PM
Who doesn't enjoy sanding! I love it :)

Not long ago, I saw an ad for a job at a local studio. It was for a sanding grunt. Sanding all day, every day. Nothing but sanding from morning till evening.

See? There are entire jobs devoted to what we love. :)

I made furniture professionally for a short while, and we definitely had a "sanding guy". He'd been doing it for seven years and was as content as he could be. All day, every day for seven years.

Of course, we all thought he had fried his brain in the 60's using too many psychadelics... but I guess whatever you need to do to prepare yourself for seven years of sanding could potentially be worth it.

Xanthorrhoeas
4th June 2017, 07:08 PM
Hi Mary and welcome to the forums. Sanding is sometimes a contentious issue as you will see from the above to and fro. Sanding on a lathe has some differences to sanding flat panels because the lathe alternately offers up different grain direction and so some responses will be based on turning, which is not relevant to your work.

However, some points are clear to all:
1. use good quality paper
2. use a cork block
3.stepping up the grits gradually will help (80, 100, 120, 150, 180, 240, 320, 400 ...) especially when you are starting.
4. Never move to the next grit if you have not removed the scratches from the grit before. That is, if you start with 80 grit then move to 100 grit, make sure all the scratches from the 80 grit are removed before you move to 120 grit, etc.
5. Finish the inside of a box as much as possible before assembly (I even apply the final finish) because it is much harder to do afterwards.

One thing that has not been made clear to you is that not all random orbital sanders are the same. It is not only the brand quality of the machine but also the radius of the random movement. Some ROS are very aggressive as they are really designed to use under paint or for removing paint. Yours may be in that category, I don't know. I had a Ryobi ROS when I was a wood butcher, it was great with coarse grits to remove paint as part of house renos. But once I set my sights on doing fine woodwork it was quickly discarded.

There are good quality ROS (Bosch blue (professional grade) Festool or the new Mirko sanders as well as others). They will all produce good results.

I started out in restoring Australian Antique furniture. Back in the 1800's sandpaper was not really a thing. Timber was mostly finished with planes and card scrapers.

I recommend that you get yourself a card scraper and a burnisher (to put the 'hook' edge on it) and do some practice. If you find the edges digging in then just use a file to round the sharp corners away - problem solved. Make sure the edge of the scraper is perfectly flat before you use the burnisher to apply the hook. There is a fair bit of info on the web about using scrapers.

The most helpful thing to me when I started trying to achieve fine woodwork was to do some courses with professionals. I really recommend that you look for some professional woodwork classes near you in Melbourne. Learning on your own is very hard work and many people either give up or settle for poor quality because they don't know any better.

Until I took classes I had wasted a lot of money on substandard equipment that I had to sell at a loss. Depending on what kind of woodwork you want to do you may not need to buy much in the way of machinery as hand tools, in experienced hands, can achieve a great deal. I have hand tools, and use them, but also have some fairly heavy duty machinery but not everyone needs to do that. However, cheap machinery is just a pain from my experience.

I have also found some woodwork magazines to be worthwhile, though they eke out the info to keep you hooked.

Good luck

David

Mnb
4th June 2017, 09:26 PM
Thanks for the summary David. That was useful .

You may be right about my sander.
The Ros has been useful for getting marks out of my bad resawing pieces and glue ups of those into lids or bases. It also made it simpler to hand sand after using the Ros to 120. I don't have dust collection and have only used one type of sandpaper which may make a difference. I thought it was my inexperience but I had an old 1/4 sheet sander that didn't last long and I seemed to get better results with that than I do with the Ros.

I inherited tools from my uncle when he died, which is how I got started because I wanted to learn to use them. I have also been cleaning my Dad's old tools as he has dementia. That's why the combination sander was scratched - because I didn't know what I was doing. It does mean that I don't know how much of the issues are the tools.

I think you're right about the classes. The internet has been fantastic but... I can't really afford to go to classes but I have just found a woodworking club near me so I will give it a go.

It may have been frustrating but I don't think I would have learnt as much if I had started with nicely milled wood and cut it on a saw that produced nice square cuts. But now I know what to do basically, I need to get good at it.
-----------

I will give the card scraper another go. I spent a bit of time investigating the concept but was just getting it happening when I moved and haven't tried again. It makes sense to me and I absolutely love book matching which I believe it is suited for.

Cork? I have read that you should have a backing for the sandpaper but opinion seems to vary. Maybe that's why I was scratching. It seems to work best if I slide the paper over gently and make sure to keep it flat and the surface of the paper touching consistently. A bit of wood with a couple of layers of paper works ok but I have to be gentle.

I have actually come to enjoy the hand sanding because you get the feel of the wood and see it happening. Even though I find sanding frustrating it is also magic to be able to bring the potential beauty of the wood out. Sometimes I don't want to cut a piece of wood because it is so beautiful and to be able to make something that does justice to it is awesome. I guess I'm a bit weird but I want to be able to show the beauty of it.

I really should have joined the forum earlier:)

FenceFurniture
5th June 2017, 10:48 AM
I don't have dust collectionThis creates a few problems Mary. The obvious one is breathing in the dust, but it also causes you to go through sanding discs faster because of heat build up which has two facets to it. Firstly it stops dust from clagging up the disc , which causes heat build up. Secondly, it causes air to rush over the job/disc/sander which keeps everything cooler. This becomes particularly important if you are sanding back paint or lacquers, as well as some particular timbers that are are resinous.

Hand sanding probably doesn't create too much invisible dust, but machine sanding most certainly does. Invisible dust is actually the dust that gets us the most, for two reasons. It is invisible because it is so fine, and therefore penetrates lung tissue more easily and deeply. Second, because it is invisible, we may be tempted to take off the dust mask because the air appears to be clear and we think there is no danger, when exactly the opposite is the case. Be aware that there really is no cheap solution to dust control - cheap vacs just tend to grind up the dust and spew it back out into the room as even finer dust - and therefore even more dangerous.

If you search for "invisible dust" on the forum you will get hundreds of hits, if you wish to research it further.

As others have said, make sure you don't skip grits, and get the previous scratch pattern out. This actually doesn't cost more in sandpaper - just a bigger spread of more grits in smaller quantities.

Mnb
6th June 2017, 05:10 PM
I will research invisible dust. I am somewhat prone to taking the mask off and have been wondering about the damage.

I want to say thank you to everyone that has replied. All the posts have been useful and I haven't responded to many that I was intending to.

I feel much clearer now though the ability to actually do the things I know to do will take time.

Looking back, I used to use old sanding pads and when hand sanding but seemed to have unlearnt that at some stage. Same with sanding before making or assembly- I didn't do it because my mitres kept failing then I somehow forgot. I had become completely confused and you have all helped.

Thanks everyone.

Xanthorrhoeas
6th June 2017, 06:48 PM
Cork blocks are the standard backing to use for hand sanding. There are lots of different brands (not just the one pictured below) and as far as I know they are all pretty much the same. Only $3- 4 each available lots of places including from the big green shed.

413688

DUST

One of the simplest ways to avoid nasty dust is to have your dust extractor or vacuum cleaner outside the room that you are working in. Unfortunately, the ultrafine dust is only moved by a large flow of air, so the small vacuums are not very good - though better than nothing as long as you use a very good mask as well and have the vac outside. The paper masks are ineffective, a good silicone mask with the correct cartridges is more effective - the dust experts on the forums don't believe in any of them but I think something is better than nothing. the dust extraction section of these forums is really educational.

Darklord
7th June 2017, 10:16 AM
Might be worth getting a copy of "A Polishers Handbook (http://www.ubeaut.com.au/book.html)" this will not only help you with sanding but also finishing and is a great read as well as the best finishing information for all from beginners to advanced woodworkers.



I had one of the original from years ago and it has served me well.



Highly recommended.



Darky

q9
7th June 2017, 07:43 PM
I genuinely enjoy finishing, and all that entails.... including sanding. Stuff would have to be bad before I'd be using 120 or less. 80 is really grinding...

Be sure to hold your ROS flat, not on an angle, and don't apply too much downward pressure. Let the paper do the work. For me it is 240, 320, 400. But but 240 and first coat of sealer/finish is a good start.

Sent from my MI 5s using Tapatalk

Mnb
8th June 2017, 06:55 PM
xanthorroeas - thanks, I have seen those and will get a couple. I was using a sort of foam thing that had sandpaper on it but I was wrapping paper around it. When I realised I was creating scratches while getting rid of others I started using just my hand so I could feel what was going on. I wasnt thinking properly with being sick and just kept going like that until this thread.

I will have to consider the dust situation. I had a couple of silicon masks and will be more conscious about wearing one now after looking at the info that- sorry I forgot- mentioned.

q9 - haven't done much finishing but I have enjoyed what I have. The first box I was reasonably happy with the sanding of, which was also only the second time I successfully cut the lid off a box, I used blackberry juice for the lid panel. It was too red on its own but two blackberries mixed with a thinned down walnut stain was awesome. I ripped a piece of the same wood as the box into thin pieces and turned them on their side to make a pattern.

Sorry. Yeah I have been starting too coarse. Think I was used to sanding to flatten and after cutting badly -so I didn't know that it's a different story at the end.



EVERY one - I got a "that looks good" from my dad on the sanding of the box I have just done. He's in the early stages of dementia but even though he's not able to show me or explain he still knows a lot. I had only got frowns or "better" before now though he never seems discouraging somehow. Thanks again guys.