# I can't sand flat!



## shauny (Dec 17, 2011)

I'm having issues sanding flat, iv only got a palm sander. I've done to little projects now both requiring some sanding to make mitres look ok I guess. I was wondering. If i got a belt sander would I be able to sand flatter and not end up with a very no flat surface.


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## Yeorwned (Jan 9, 2010)

A belt sander can actually make it easier to create concave surfaces in your material, as a good model sander can remove some serious material quickly. Do you have any hand planes? That would obviously be the tool of choice if you want to produce a smooth, flat surface.

If you want to stick to the sander realm, even a random orbit sander will do you better good than a typical palm sander. I use a random orbit sander much more often than a belt sander.


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## shauny (Dec 17, 2011)

Well I'm part way thought making a photo frame. i want to get a smooth even finish on the top. the problem is its make from plywood. i do have a black plane. but if i use that i will be going across the direction of the laminates. i may have no explained this very well but hopefully you can understand from the photo what i mean. your help is much appreciated


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## HowardAcheson (Nov 25, 2011)

EDIT: Well, I see your current posting and my response is not really specifically relevant. But I'll leave it in case it might be useful to others.

In our shop, we used 4" belt sanders to flatten panels and wide boards. But, as said, it takes experience to be able to do it without causing bigger problems.

Basically, we would start off by dragging a straight edge along and across the panel marking the high points with pencil squiggles. Then, using 80-100 grit belts on the belt sand we would sand these high spots until the squiggles were gone. Then we would again use the straightedge and again mark high spots as before. Then sand these areas. Maybe it needs a third time to get the panel flat. 

Once it was flat, we would use a 1/2 sheet orbital sander with 100 grit paper. An orbital sander will do the best job of final flattening and will keep flat areas flat. Sanding from 100 grit up to 180 grit without skipping grits will leave a flat panel. Sanding beyond 180 is generally not useful. Our workers could do one side of a 20x40 panel within 15-30 minutes. We didn't have a flat bed sander and never felt we needed one.

We only rarely would use a ROS on panels. ROS have a tendency to not sand flat or to make a flat sanded panel wavy. They're fine for some things but not for panel flattening.


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## woodnthings (Jan 24, 2009)

*dude, that's a small frame*

So just stick a full sheet of 100 grit down on a flat surface or tape it and slide the frame back and forth across in all directions and diagonally. It should be flat in about 5 minutes. :yes: Then you can go to 180 and do the same. I would not use a block plane on plywood end grain like you show. :no: bill


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## sawdustfactory (Jan 30, 2011)

The key to sanding flat with a palm sander or ROS is to keep the tool flat. Sounds easy but really isn't for a lot of folks. Don't tip the tool. Keep the sander moving, don't stay in one place too long. Feel with one hand while you sand with the other. Let the machine do the work, don't force it. Change paper more often than you think you should.


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## cabinetman (Jul 5, 2007)

sawdustfactory said:


> The key to sanding flat with a palm sander or ROS is to keep the tool flat. Sounds easy but really isn't for a lot of folks. Don't tip the tool. Keep the sander moving, don't stay in one place too long. Feel with one hand while you sand with the other. Let the machine do the work, don't force it. Change paper more often than you think you should.


+1.:yes: Either a finishing sander or a ROS would be my choice. Keeping/making flat is all operator technique. 










 







.


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## shauny (Dec 17, 2011)

I thank you nice folk for offering valid and very useful things to consider. I am however going to try woodnthings method. also you're right it is a very small frame. it was bigger but tried taking a router to the end grain of plywood. i know what a silly mistake to make, i soon learnt that lesson.


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## jredburn (Feb 20, 2011)

*sanding flat*

One way to flatten out a board is with a Chinese scrapper. It is a square piece of metal that is sharpened on each side. You hold it in your hand and drag it across the top of the board. It will scrape off a fair amount of material rather quickly. It will also level the high spots,
A cheaper scraper is a replacement blade for one of the larger box cutters. Take a piece of large diameter dowel and cut a slot longways in it. Almost all of the way through. Drill a couple of holes through the dowel at 90* to the slot about in the middle. Put a small bolt through the holes and slide the blade into the slot up against the bolt. Put a nut on the bolts and squeeze the slot shut against the blade. You have a dead flat, sharp scrapper.
Regards
Joe


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