reelguitars Posted May 20, 2015 Report Share Posted May 20, 2015 Hey guys, I've made a nice flat sided balsa bait out of medium density 3/8" balsa. I have 3/16" roundover router bit mounted in a perfectly flush table to round over the edges. Two things are happening here...1)even though I have the bit perfectly set to hit the center of the bait, when I flip it over to rout the other side, the second edge seems to cut a little deeper so when you look down the bait from the nose to the tail, one side looks a little higher than the other...I'm thinking that the bearing is able to move closer to the bait several thousanths of an inch, thus causing the problem. 2) the baits come out perfectly smooth except in a couple of places...where it looks almost like the grain of the bait is being aggravated by the router, thus causing these imperfections. Trying to sand out these problems only seems to make them worse...could someone please tell me what I'm doing wrong? I have a great bait, I just want to put a great finish on it. Thanks in advance for your help. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted May 20, 2015 Report Share Posted May 20, 2015 I am not sure why this happens, but I have noticed it too. Possibly because there is less material on the second pass, allowing the cutter to dig in more. The second problem is, that because you have designed for the two radii to exactly meet, the slightest error is very visible. I stopped trying to do this and went for a smaller radius and blended the two across with sand paper. You could try shimming the lure up a tad, to introduce the gap between the radii. There will be more sand paper work, as there will be an edge on the flat side that will need sanding out. I never thought of this when I had the problem! Dave 2 Quote Link to comment Share on other sites More sharing options...
Travis Posted May 20, 2015 Report Share Posted May 20, 2015 Likely compressing the bait during the first pass. Balsa is so soft doesn't take much pressure to distort it. Super glue the path of the bearing and see if that helps. The grain being raised is multiple issues likely. Dull bits, cutter speed, feed rate, etc.. and end grain. Quote Link to comment Share on other sites More sharing options...
Musky Glenn Posted May 21, 2015 Report Share Posted May 21, 2015 The ball bearing determines how deep it cuts. If it runs past center it will cut deeper. You have to leave a flat spot in the center for the bearing to run on for each side to cut the same. Musky Glenn 2 Quote Link to comment Share on other sites More sharing options...
gliders Posted May 21, 2015 Report Share Posted May 21, 2015 Spot on musky glen I.m.o. just lower bit a tad, leave small gap, sand.use good quality bit for less tear out . 1 Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted May 21, 2015 Report Share Posted May 21, 2015 MG - Spot on X2. Of course! There is hardly any material to follow the bearing. Dave 1 Quote Link to comment Share on other sites More sharing options...
reelguitars Posted May 21, 2015 Author Report Share Posted May 21, 2015 Guys...thank you all for your quick responses. I was actually having a little better luck using a 1/8" roundover bit but my son (who fishes on the Dobbins pro staff) believes there is a way to actually do this with a 3/16" bit with very little sanding. In this case, I don't agree with him. I'm going back to what I was doing before. I don't mind a little sanding...after all...this is a handmade crankbait. I will post some pics of this finished product. Thanks again for your responses. David... Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted May 21, 2015 Report Share Posted May 21, 2015 ReelGuitars - It will be at least interesting to read what he has in mind. We don't have all the answers all the time, so keep an open mind and bring his ideas to the forum. Dave 1 Quote Link to comment Share on other sites More sharing options...
mark poulson Posted May 21, 2015 Report Share Posted May 21, 2015 Maybe sealing the blank, once it's profile is cut, with crazy glue on the edges might keep the balsa strong enough, but I've never been able to make anything like that work. I do what Musky Glenn suggests. 1 Quote Link to comment Share on other sites More sharing options...
clemmy Posted May 23, 2015 Report Share Posted May 23, 2015 I would think you would need to use a jig for safety, but then couldn't you use a 3/8" bull nosed bit? Note that I have never used a router on my baits, so take it with a grain of salt... Quote Link to comment Share on other sites More sharing options...
mark poulson Posted May 23, 2015 Report Share Posted May 23, 2015 There are router table jigs, with pin or bearing suspended over the actual cutter that follow a master clamped on top of the workpiece, so you can route a true half round edge without overlap. https://www.google.com/search?q=gooseneck+overhead+pin+router&newwindow=1&espv=2&biw=1280&bih=845&tbm=isch&imgil=vZhCACXJfdmmiM%253A%253B93chSGclqdkZwM%253Bhttp%25253A%25252F%25252Fwww.thisiscarpentry.com%25252F2013%25252F06%25252F28%25252Fgooseneck-overhead-pin-router%25252F&source=iu&pf=m&fir=vZhCACXJfdmmiM%253A%252C93chSGclqdkZwM%252C_&usg=__wZqLOZVnvI-nUQwPrJK8x_9_VME%3D&dpr=1&ved=0CCcQyjc&ei=vpBgVbq6IIKxggSO3YHwAw#imgrc=vZhCACXJfdmmiM%253A%3B93chSGclqdkZwM%3Bhttp%253A%252F%252Ftic.wpengine.netdna-cdn.com%252Fwp-content%252Fuploads%252F2013%252F03%252F001-1.jpg%3Bhttp%253A%252F%252Fwww.thisiscarpentry.com%252F2013%252F06%252F28%252Fgooseneck-overhead-pin-router%252F%3B920%3B704 Quote Link to comment Share on other sites More sharing options...
riverotter Posted May 25, 2015 Report Share Posted May 25, 2015 they do make router bits designed to cut the shape your looking for that does both side at once. not sure the safety aspect of it. Quote Link to comment Share on other sites More sharing options...
riverotter Posted May 25, 2015 Report Share Posted May 25, 2015 (edited) bullnose router bit and they even have some that are like a pool cue tip shaper I used to have with metal shavings instead of the cutting bits. those should be safer.. edit those appear to be diamond cutters for countertops. they are a little pricy as well. cheapest one I see is 65$ Edited May 25, 2015 by riverotter Quote Link to comment Share on other sites More sharing options...
riverotter Posted May 25, 2015 Report Share Posted May 25, 2015 (edited) did not see the above post saying the bull nose bit but I agree and think it may work. im going to try one. Edited May 25, 2015 by riverotter Quote Link to comment Share on other sites More sharing options...
RayburnGuy Posted May 25, 2015 Report Share Posted May 25, 2015 I use sand paper glued inside different size pill bottles to shape the top and bottom contours on balsa baits. As soft as balsa is it only takes a few seconds to accomplish this and there is no chance of making my fingers shorter. Ben 2 Quote Link to comment Share on other sites More sharing options...
Travis Posted May 25, 2015 Report Share Posted May 25, 2015 I turned the profile on disc and lined with sand paper, then chucked on drill press. Sands profiles quickly in balsa. Hazmail did one also and had a thread some time ago on the subject. 1 Quote Link to comment Share on other sites More sharing options...
riverotter Posted May 26, 2015 Report Share Posted May 26, 2015 sandpaper in pvc pipe cut in half works really good 1 Quote Link to comment Share on other sites More sharing options...
