# bit too long?



## thammons (Mar 26, 2012)

I started routing today, so my question is probably the result of inexperience. Today I made a drawer, and used rabbet joint (bit in table router worked fine) and a slot for 1/4 plywood for the bottom. When I set up the router with my undersized 7/32 Whiteside bit )Whiteside SC218 - 7/32in Cutting Diameter, 3/4in Cutting Length, 2-3/4in Overall Length) in the table, the bit stuck up about 3/4 inch -- too long for the depth of cut I needed to make. Even if I "backed down" the router as low as it seemed it should go. I managed to do the cut by clamping a half inch piece of plywood to the table surface to raise the table in front of the bit (perhaps dangerous?) so the wood only got cut about 1/4 inch deep.
I think I had the bit in properly. I don't know what I did wrong. ??
BTW, I couldn't find an existing thread to attach this to.


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## williamm (Oct 10, 2011)

*Bit does not seem too long*

You stated that the cutter on the router bit was only 3/4" long and the cutter was 3/4" above the table. It sounds like you didn't have the router lowered to a proper cutting depth.
Maybe a picture would clarify the problem so you could get more of us to help you.


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## mgmine (Jan 16, 2012)

I'm guessing that your router doesn't go low enough. Do you have a plunge router? They tend to be able to lowered a little more. The way you did it sounds like the only way around your problem.


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## Dmeadows (Jun 28, 2011)

Terry, was the bit fully inserted into the collet? It should be inserted all the way and then backed out about a 1/16th of an inch or so to keep it from vibrating loose! A 3/4" cut length bit should not be too long!


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## thammons (Mar 26, 2012)

You're right, but I don't think I could lower the router more -- it's as PC 690 in it's fixed base -- because I believe that motor has to be in the base at least enough so that all four of the little pins are inside the base (in the spiral grooves), thought I could be wrong. And thank you for responding.


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## thammons (Mar 26, 2012)

Good idea, I'll try that. I looked on this Router Forum and some other places that came up from googling "plunge router and router table" and several things came up. A few commenters said that using a plunge router on a table might be less safe, other said they'd been doing that for years and it worked fine. Another said it even worked better once the springs were removed when using it with a table. How well this all works seemed to depend on which plunge router the person was using. Anyway, and interesting possibility, and thank you, I'll try it.


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## thammons (Mar 26, 2012)

I'm pretty sure it was -- the entire shaft was inside the collet with only the cutting part showing, then I backed it off 1/16 or 1/8 inches. In fact, it was a bit touchy to pull the bit back out because I had to pull on the cutting part -- using an old rag.
Also, before trying to use this straight bit I successfully used a rabbet bit (also from Morningside) and like with the straight bit nearly the entire shaft was inside the collet after I backed it out 1/16 inch.


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## PetersCreek (Mar 13, 2012)

I still have the 690 as a backup-to-the-backup router and I can't say I ever experienced this problem with a bit of similar size. But it does look like the Whiteside's shank is ½–¾" longer (judging by OAL-CL) than many similar straight bits. Still, I'd think you would have enough adjustability to get closer than you did. Can you measure and post the min/max distance from the collet face to the subbase? I'll compare it to mine when I get home, if you like.


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## Leifs1 (Dec 16, 2009)

Hmm did't you say that bit overall length was 2 and 3/4" ? thats about 70 mm. That is a very long bit. Standard size bits are about 2" or 50mm I think.

regards Leif


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## wbh1963 (Oct 11, 2011)

As long as the plywood you used to raise the workpiece covered enough of the table surface to keep everything stable, it sounds like you just made your first 'jig' to me, and congratulations are in order! 

You could also take that same spacer board all the way back to the fence by cutting out some of it for the bit to pass through, (and may have done it that way)

Thinking about the challenge you have described I also considered using the plastic sub base on the router as a template for making a thicker sub base, perhaps out of 3/4 plywood or something similar. Longer machine screws that penetrate the spacing sub plate would be the simplest approach to the 'fastener' riddle created by making a thicker plate. You could also attach the router to the ply plate, rotate it a little and use different screws to mount it on the table.


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## thammons (Mar 26, 2012)

Here are some measurements including, I think, the one you were asking for:

I’m using a 690 PC router in a 1001 (basic) base and a ½” collet
•	depth of the cylindrical “hole” in the collet is about 1 ¼”

Assuming I understood PetersCreek’s question: When router is fully extended through the sub base plate, the tip of the collet extends about 10/16-11/16” past the face of the plate; when the router is fully retracted, the tip of the collet is recessed about 1 3/16” from the face of the plate; so the total travel is about 1 13/16”
•	a variable here is my understanding with how far back or “out” of the 1001 base I can have the router motor and still have it be firmly grasped by the base and safe – maybe I’m being too timid, but if I back it out any more one of the four little pins will no longer be engaging the base

Whiteside 7/32 straight bit
•	overall length of bit (OL) is 2 ¾” and cutting length (CL) is ¾”
•	shaft ½” diameter, length of shiny part of shaft about 1 5/8” (vs 1 ¼” for rabbet bit)
•	when fully inserted into my collet then backed out about 1/16-1/8”, the length of the bit protruding from the collet is 36/64-40/64” (= 9/16-10/16”)
•	with the bit in place in the collet and the router fully retracted, the amount of bit protruding beyond the face of the plate is about 3/16” – this is too much if I’m trying to cut a 1/8-3/16” groove into the ½” plywood sides for the drawer I was making

Thanks,
Terry


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## thammons (Mar 26, 2012)

My "jig" was pretty crude! I like your suggestions about making it far better, and I'll try them, especially if I can't find a simpler conventional solution such as finding out I'm not placing the motor correctly in the router base.
I think jigs are among the most interesting aspects of woodworking whether I'm attempting to design and make one or seeing the clever ones that others have made and are sharing.
Thanks,
Terry


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## wbh1963 (Oct 11, 2011)

thammons said:


> My "jig" was pretty crude! I like your suggestions about making it far better, and I'll try them, especially if I can't find a simpler conventional solution such as finding out I'm not placing the motor correctly in the router base.
> I think jigs are among the most interesting aspects of woodworking whether I'm attempting to design and make one or seeing the clever ones that others have made and are sharing.
> Thanks,
> Terry


I'm not familiar enough with your particular router to speculate on whether the height adjustment or mounting mechanisms are 'as they should be'. That being said, I just thought about what you mentioned in your post and expanded on the notion of making it work even with the bit that high above the table surface.

Please do verify the motor is correctly and securely installed in the base! Routers operate on the high side of 20,000 RPM. The idea of one mounted in a table 'vibrating it's way free' of the bracket isn't my vision of a lucky day. 

By my way of thinking, fences themselves are jigs, simple one perhaps, but jigs all the same.

I wouldn't be a fan of using a spacer block that left a gap the workpiece could dip down into between the fence and the spacer, but have to admit in a pinch, might do a quick cut that way just to get it over with (if I didn't have a lot of cuts to do.


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## thammons (Mar 26, 2012)

I just wanted to thank you for your post some time back. Your comment about making a jig helped me think about jigs more broadly than I had before. And I did do some thinking about my putting plywood on the router table to in effect raise the table height and reduce the degree to which the bit had to be exposed and the depth of the cut. And that made me think about other aspects of how to do this task such as how much of a gap should be over the bit (as you suggested), how the chips would get out of the cutting space, etc. Thank you.
th


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