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Sandpaper is graded by the size of grit. The larger the grit, the smaller the number. 80 grit is coarse, 150-120 medium, and 220 and higher fine. 400 and higher are very fine. You will find these grits in any well stocked hardware or home improvement store.
Selecting the proper sandpaper depends on what you mean by “sand down the planking.” If you are trying to shape the hull to correct planking mismatches and areas of unfairness then you want sandpaper that cuts, not polishes which is what the fine and very fine grades do. For this job, I would use 120-150 grit paper. Good sandpaper uses carborundum rather than sand for grit. 3M makes a good product. Use a sanding block. Once the hull is shaped to your satisfaction, switch to 220 grade to remove scratches from the coarser paper.
I know of no ship modeling application that would require ultra fine 1200 grit paper.
Roger
Selecting the proper sandpaper depends on what you mean by “sand down the planking.” If you are trying to shape the hull to correct planking mismatches and areas of unfairness then you want sandpaper that cuts, not polishes which is what the fine and very fine grades do. For this job, I would use 120-150 grit paper. Good sandpaper uses carborundum rather than sand for grit. 3M makes a good product. Use a sanding block. Once the hull is shaped to your satisfaction, switch to 220 grade to remove scratches from the coarser paper.
I know of no ship modeling application that would require ultra fine 1200 grit paper.
Roger
... with 1200 grit sandpaper, you will sand for hours, if not days. Technically speaking, 1200 grit is very fine sandpaper, used mainly for finishing surfaces. However, there are no golden rules as to what grit to use.
How much material you will need to remove? If it is first-layer planking and you need to build a base for second planking, 120 ~ 140 should suffice. Again, we don't know the original state of your hull and how much material you may need to remove. Sometimes 80 grit should be just about right to start. Also, what grit sandpaper to use depends on the plank material. The harder the wood the smaller the size of grit sandpaper you will use.
Once the initial sanding is done, you may use 240 ~ 360 to make the surface smooth, and then 600 and so on. The last thing to prepare for oil or paint is to use scrapes. Scrapes will remove all sandpaper traces.
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sorry I forgot to tell you the second layer my mistake sorry, but I see the proceeded of all grids its very well instructed, thank you for this
You can't start with 1200, it will just burnish everything you are trying to sand out.
The materials for most model ships don't benefit from anything finer than 400 grit, in my experience. I use 80 150, 220, 320, and then 400.For the second layer, I wouldn't use more than 220, those strips are just too thin, you will burn through them with 150.
The materials for most model ships don't benefit from anything finer than 400 grit, in my experience. I use 80 150, 220, 320, and then 400.For the second layer, I wouldn't use more than 220, those strips are just too thin, you will burn through them with 150.
It depends on what you are doing. if you are wanting to take a little material off so a piece fits, I use 100 grit paper.
if you are working to put a finish on your hull, start with 150 to get all the edges even, then go to 180 a little bit, then 220. Then a final sanding with 320 if you wish.
Also, make sure you wipe off the sawdust between grits or you could get marks in the wood where the wood particles and even the sanding grit medium can get under the current sandpaper and put marks in the wood.
I hope that helps.
if you are working to put a finish on your hull, start with 150 to get all the edges even, then go to 180 a little bit, then 220. Then a final sanding with 320 if you wish.
Also, make sure you wipe off the sawdust between grits or you could get marks in the wood where the wood particles and even the sanding grit medium can get under the current sandpaper and put marks in the wood.
I hope that helps.
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There is no 'best' when using abrasives.
There is a vast range of abrasives, and your challenge is to use the most 'appropriate' for the task in hand.
The tasks for abrasives ranges across crude shaping - in the 60 grit area (that is, the grit is sized to fit a mesh of 60 to the inch)
So many people nowadays use power tools for wood shaping, and maybe start at about 80, with power tools to remove large amounts of material, and shape the substrate.
In the sphere of cabinetmaking though, I would aim to cut timber to the correct sizes, and avoid abrasives.
Why? - because abrasives alter the surface finish, and the vessel cells, or pores, become blocked with dust, and the chatoyance of the finished (varnished) product will alter.
And that goes to the heart of using abrasives in model building.
Firstly, understand that an abrasive sheet or tool is a series of very tiny sharp edges that cut the substrate. When they go blunt, you need fresh abrasive. When you use them, they leave a surface like a ploughed field - a series of grooves. The grooves will be sized to suit the grit size, so coarse abrasive = big grooves. That may be good - for painting onto , say, but bad for accurate dimensioning.
So switch to the next grade, My stock includes 80, 120, 240, 320, 400, 600, 1200 and 2000. Mostly stearated SiC (Silicon Carbide).
For our purposes, abrasives will work best on hardwoods, and we need fine grained timber to be scale(ish). Broadly speaking, a hard timber is needed if you go down only to 400 grit. In my other world, I use stuff like ebony and ironwood, and they will take finer grades and even buffing compounds to bring up the potential for gloss like surfaces.
To come back to the question. the most appropriate abrasive to use is the one that yields the surface you desire in terms of appearance.
Given a reasonable surface to start, I would maybe begin with 240, and stop at 320, or maybe 400.
You also need to consider how you apply it. Avoid using your fingers - they just follow the bumps. Make up a series of blocks from cork that will let you reach into the scuppers or bows or wherever. Make concave surface blocks to handle the convexities if you are working on the outer hull. At our scale it's probably best to glue the abrasive to the block, though for the outer hull merely wrapping a block and holding the edges in your fingers will work.
Work over the surface, diagonally to the grain with your first grit, until the surface lodes all its ridges. Swap to new finer grit, work with the grain until all marks from the first have gone. If you want or need a finer finish, move to the next finer grit, with the grain, and so on.
You may also want to make up a small test bit of deck on some scrap, and 'sand' it to different grades, then use your eventual finish - varnish, French polish(lacquer/shellac) or whatever. This will inform your choice of finishing (degree of physical abrasion and top coating) You may find that you can leave off the last grade, or need another.
Go slow, and take care
Jim
To add a further dimension to this discussion, sandpaper is available with different abrasives, which have different characteristics. For modeling applications, the most common are garnet, aluminum oxide, and silicon carbide. Garnet is a traditional abrasive long used for woodworking and works well on raw wood, especially end grain. The sandpaper you pick up at the hardware store is most likely aluminum oxide. It works well on raw wood and on paint and other finishes but is more likely to cause scratches than garnet because the abrasive grains fracture more easily. Silicon carbide on a waterproof backing (wet & dry sandpaper) is good for sanding finishes between coats, especially if the model will tolerate some water during the process, but it does work dry. Speaking of backing, I have lately used some 3M paper with "No-Slip Grip" backing, which is more flexible and tougher than standard paper. It seems to work well on curved surfaces. Fair winds!
A couple of natural materials are abrasive enough to sand wood and polish metals, etc. Some Ancient Egyptian murals depict woodworkers, sanding furniture with sandstone blocks (what’s in a name?) Shark - or dogfish skin was known since Roman times.
While sandstone is too rough to finish instruments, shark skin is very fine (almost like #1200 wet or dry sandpaper). But it’s rather hard to get and quite expensive. Planning and scraping are great methods for getting a perfect surface, but sometimes, they aren’t what we’re looking for.
Maybe they use another option… And it’s very cheap and easy to get. Because it grows by the side of the road. Or at least here in the Netherlands, it does in some places. A little green plant, often regarded as a weed. Its name: is Equisetum, better known as “Horsetail” or “Heermoes” (Dutch). There are several varieties, the larger is called “Schaafstro” (Planning straw) in Dutch. While that one is harder to get, the smaller varieties are all over the place. Just try it when you go for a walk. Pick some horsetail and start sanding the top of a nail. You will soon discover that the fine lines get rubbed out, and it leaves a smooth surface.
Hi Jim I live in Australia so cannot try the weed. The Aboriginals of this country are great carvers and used stones to sand down things. They also used fire to hollow out wood and then if they were making a Didjeridoo, they sometimes used hot pebbles to help smooth the internals of the hollow
You don't have to use weed unless you want
to. Today, we have so many varieties of sanding paper that it is just a matter of purchasing.- Joined
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mm, I use 1200 if I'm getting to fine polishing. Something like a 2 part finish is very hard, and to get a 'real' glass like polish you work through to paste compounds that are, literally, used to polish rather than cut. Imagine the kind of refinishing you might do on a car. Begin with the usual grits, using a machine of course, and cleaning down well between changes to ensure there are no stray 'large' grits to scar the next level. 600 to 1200 to 2000 and on to paste compounds and sponge buffs.
Not applicable to a ship model - even a fine varnished wheelhouse was never finished to high gloss.