Thread: Question - Managing Tearout When Routing Edge Profile On Round Table

Climb cutting is the way to go. cut it in multiple passes to avoid the router racing away from you. I usually cut deeper n deeper passes because I rarely have access to different sized bearings as well as being quicker than changing out bearings.
Use sharp router bits, if the bit has been used on MDF, it isnt sharp anymore. A light hone with a diamond file is a quick way to create a sharper edge.

Cutting a circle, think about it in 4 quarters. 2 of those quarters will have cutting down the grain, and you should get a nice edge whether you climb or conventional cut it. The other two quarters have you cutting up the grain and this will be where your tearout will occur.

Some tearout will occur. just take it easy being careful not to burn the edge. if the timber splinters out the edge, stop immediatly and carefully remove the splinter because if you keep ushing through with router, a much bigger splinter will be created.

You could also try doing the bulk by hand and then just using the router for the final little bit to give you a uniform curve.

Personally I would use a nice sharp float in preference to any other handtool . They give a superb result on endgrain. In fact, this would be what I would use for the whole job - skip the router - it is surprising how uniform a result cab be achieved with a float.

For the rounded corners (not the edges) on this stool base, I used a float. Cut off the waste with a mitre saw and then set to.

Please excuse my ignorance, but what is a float? Hi FF, can you show us a pic of one in action please?

I agree with the climb cutting suggestion, but this only has to be done where the grain is likely to tear out, probably less than half of the table perimeter

Originally Posted by FenceFurniture

You could also try doing the bulk by hand then route, .... or...... skip the router - it is surprising how uniform a result can be achieved with a float.

Thanks for those suggestions. I tend to use a mix of noisy tools and sweat driven tools, so your suggestion interests me. However, as it's so hot and humid at the moment, a power tool solution could be the easy way out for me this time. however you suggestion is still tempting. For the uninitiated, can you please confirm that a "float" is another name for a fine cut rasp, or have I got it wrong ?

thanks,

Roy

Ok, a float is not really a rasp, it's actually more like a file, and is derived from a milled file (not a mill file). Milled meaning that material is removed to create the teeth so that that the teeth are below the surface of the blank. With a normal file the teeth are punched and so are above the surface of the blank.

Have a look here:
http://www.hand-stitched-rasp-riffle...loat-2588.html
and click on both the images at the bottom. This is the latest float that I have developed. It has teeth on one side that are perpendicular to the length, and on the other side the are slightly finer teeth, but importantly they are angled. This creates a smoother finish.

So, hog off with the coarser side, and finish with the finer side. The result is superb - no sanding required, particularly on end grain, and going 45° across end grain.

Really, the only difference between a float and a milled file is that the teeth are usually perpendicular. Probably the biggest difference, although subtle, is that a float is not hardened to 65Rc like a file, but somewhere around 52-54Rc. This is because they need to be sharpened with a triangular file when you receive them (that's why they cut so brilliantly).

Floats are also available here:
http://www.henryeckert.com/index.php...ry&path=39_135

Note that they are different dimensions (toothed area not as long or as wide), and that there are no oblique teeth floats in that range. The number of teeth per centimetre may differ as well.

Thanks FF, you learn something new every day on this great forum

My experience is limited but having recently completed a table in a figured Qld Maple variant that I had many problems with, I'd suggest that it's not just a matter of having sharp tools to avoid tearout in some maple. I found scraping to be most reliable way to avoid tearout. I ran a bead along the table legs and apron an for that I had the best result using a scratch stock.

Originally Posted by Fuzzie

My experience is limited but having recently completed a table in a figured Qld Maple variant that I had many problems with, I'd suggest that it's not just a matter of having sharp tools to avoid tearout in some maple. I found scraping to be most reliable way to avoid tearout. I ran a bead along the table legs and apron an for that I had the best result using a scratch stock.

Thanks Fuzzie for that input. I'm using Maple Silkwood. Lovely stuff .... sands and finishes a treat .... but it is quite soft, and you are right about the tearout. Some of the boards had a lot of tearout after thicknessing, especially where the grain got a bit interesting. I ended up doing a fair bit of hand planning with a low angle plane to level the glued up table top, and then had to scrape some stubborn areas of tearout.

Late this afternoon I did a climb cutting test with the router and two different sized bearings on an off-cut of end grain Maple Silkwood. Climb cutting has helped a lot, but the results of the climb cut test are still not good enough - very splintery and by the time it was sanded to a satisfactory finish, there wouldn't be much of the routed profile left.

I've come to the conclusion that the best way of applying some sort of edge treatment to this table top will be to do it by hand. I don't have a float, or any moulding planes, so I'll have to make do with a block plane and sand paper, so it'll be a simple round over on the top and bottom edges. (Might be able to scrape it instead of sanding, if I can find the goose neck scraper wherever it's hiding.)

Thanks everyone for the input. All the very prompt input was very much appreciated.

Regards,

Roy

Originally Posted by AussieRoy

Maple Silkwood. Lovely stuff.

My Maple Silkwood table.

Sharpen the router bit and go in multiple passes, even cutting against the grain you'll get very little tear-out that way.

Hi, I am not sure why you are getting bad tear-out as most edge profiling bits (if not all) allow you to make progressively deeper cuts until you get the desired profile.Adjusting your router depth you can take off as much or as little with each pass you dont even need to mess a round with different size bearings etc.Providing the bearing makes contact with some part of the edge of your table.
I rarely make a full depth cut in the first pass.