Need help with drilling shelf pin holes using router and bushing guid

[Mike Nguyen]

Hi,
I have never use a router with guide bushing before and my first experience is not very good. I made a shelf pin jig for using a 5/8 OD guide bushing and 1/4 spiral bit and it burn the baltic birch plywood very bad. Is there a trick using guide bushing for shelf pin without burning. I wonder if it's the jig is the cause of the problem. In the past, I used the Rockler shelf pin jig but the holes are not always free of chipped out. Please advise.
Mike
309543

[Jerry Miner]

A. Using a plunge router?
B. Plunge-cutting bit?

[Mike Nguyen]

A. Using a plunge router?
B. Plunge-cutting bit?
Yes, I am using the Dewalt 611 plunge router and an up spiral bit.

[Kevin Jenness]

Use a sharp bit, slow down the rpm's if possible and/or increase your plunge speed. Make sure that the jig is thick enough that the waste can spill out between the collar and the workpiece. If that is your jig in the picture you can improve it by making the jig holes open-sided. Rip it down so you have semicircles at the edge and can engage the guide bushing from the side. This will speed up the operation.

[Rich Engelhardt]

Is you bit both centered and sharp?

My 611 was off center by a fair amount.

Pick up a Dewalt DNP617 Sub-Base Centering Cone for Compact Router DWP611 and a good bit.

I used the exact same setup and drilled holes in Cherry w/out any issues.

[Peter Quinn]

Your sure that's a plunging bit? Not all bits are " center cutting", though most of the spirals I've bought were. I'm thinking you are better off with a down shear bit for surface quality on delicate veneers. Relative to the burning its a short list of culprits. Either the bit is dull, or it's not a center cutting plunge bit, or you are going way way to slow. In and out, real quick, should take a little more than a second per hole total. Don't hang around with a bit moving 20K rpm's very long. And a little dust collection wouldn't hurt either.

With the drill bits like the rockler set up I've found the biggest issue is rpm's....they need more to work well than most cordless drills can provide, and most guys use them wih a cordless drill, which may work ok when e bit is brand new and razor sharp, but a few hundred holes later and it starts ripping things up. Switch to a drill around 2000rpm or more, problem solved.

[Mark W Pugh]

I hope you find the answer, because I couldn't get my router to plunge pin holes in ply. I wound up using a jig from Rockler that uses a drill centering bit and jig. I haven't had time to figure out how to fix my router/jig/technique problem.

Take a look at this thread. http://www.sawmillcreek.org/showthread.php?218309-Drilling-Plywood-For-Shelf-Pins&highlight=

[Ole Anderson]

I am also thinking dull bit and a feed rate too slow. I used an upspiral bit and a 32 mm template from Woodhaven and did several hundred shelf pin holes in Hickory ply with no burning. DeWalt 612 plunge router at close to full speed. Was your bit carbide or HSS? It doesn't take long to dull a HSS bit if you let it heat up.

[lowell holmes]

Is the bit a spiral upcut solid carbide bit?

I can't imagine a carbide bit burning the wood.

[Cary Falk]

I used the 611 with a HSS upcut spiral from Harbor Freight in maple plywood. No issues what so ever. I would guess a dull bit oe it was not made for plunge cutting.

[Bill Huber]

When I look at the picture there is just something that looks funny about that bit, does it have a rounded tip on it?

I have use my 611 and drilled a bunch of shelf pins in all kinds of different wood and never had any of it burn, plywood, hardwood and MDF.

Do you know the make and number of the bit?

[Steve Wurster]

I built a similar jig, also for use with a DW 611 and a 1/4" spiral bit. I routed something along the lines of 800 holes into plywood with that technique and had burning on maybe only a few.

I can't actually see the bit you are using in that picture. You might have to post a picture of that.

One thing I did differently with mine is that the hole for the bushing doesn't go all the way through the jig. The first time I used the jig, the 1/4" bit cut through the bottom of the jig and into the wood, effectively making it zero-clearance. That removed any tearout possibilities, and also prevented the bushing from contacting the plywood. I don't know if that had any effect in eliminating burning.

[Jim Dwight]

Dull bit seems likely but if it is not dull, I would make sure the chips are clearing the hole. I used to use a setup like that for holes and chips would usually clear but not always. Sometimes they packed into the bit and it burned. I use a Kreg jig now and like it better.

[Mike Nguyen]

Thank you for all the responses. I just checked all the 1/4 spiral bits that I have and found that they are different ranging from Freud D75102, Milwaulkee 48-23-8065, and Milwaukee 48-23-8055. The bit that burned the plywood is the Milwaukee 48-23-8055 downcut spiral, not upcut like I thought. The Milwaukee 48-23-8065 is the upcut spiral bit. I will try it later and see if I will get better result. I probably will try the Freud D75102 upcut spiral bit and the Porter cable straight to compare to see which one yield the best result
Mike
309589

[Mark W Pugh]

So, what bit does everyone else use with no problem. Thanks.

[Bruce Wrenn]

I use solid carbide, up cut spiral, both 1/4" and 5 mm.

[Mark W Pugh]

I use solid carbide, up cut spiral, both 1/4" and 5 mm.

Manufacturer? Looking for ones that are tested and work. Thanks.

[Bruce Wrenn]

Eagle America, and MLCS. The HF HSS ones work well for mortising. Haven't tried them in ply though