Horizontal Boring

gbflora3 · Post by **gbflora3** » Thu Jan 10, 2008 9:14 am

I am using the horizontal boring mode on the SS to bore a hole through a 2X2X8 inch stock. I start the bore in the center but it ends up way off center on the other end. How can I improve the accuracy? Should I be using the SS in drill press mode? Any suggestions would be appreciated.

Gary

Greenvilleguy · Post by **Greenvilleguy** » Thu Jan 10, 2008 10:02 am

Gary,

I'm going to assume you are drilling into end grain the full 8" length of stock. Is that correct?

What type of bit are you using? What size bit?

How are you holding the stock parrallel to the drill bit?

Randy · Post by **Randy** » Thu Jan 10, 2008 12:58 pm

Are you backing the bit out to clear the chips?

How fast are you are you turning the bit?

How fast is you feed rate?

charlese · Post by **charlese** » Thu Jan 10, 2008 1:25 pm

gbflora3 wrote:I am using the horizontal boring mode on the SS to bore a hole through a 2X2X8 inch stock. I start the bore in the center but it ends up way off center on the other end. How can I improve the accuracy? Should I be using the SS in drill press mode? Any suggestions would be appreciated.

Gary

It should be a pretty simple thing to get your holes aligned straight through your workpiece.

First, fully assemble you Shopsmith in saw mode. Now check that the blade is parallel to the miter slots. You may have to align the main table.

Next, check that the table is perpendicular to the blade. Make appropriate adjustments to the table.

Next, Check that the rip fence is parallel to the saw blade and miter slots.

Next, Set up the horizontal boring mode - checking the drill bit is perpendicular to the rip fence and is parallel to the table.

Then you can drill to your heart's content!

edflorence · Post by **edflorence** » Thu Jan 10, 2008 4:08 pm

Assuming that the SS is aligned correctly (see Chuck's posting), then my guess is that if you are drilling into end grain the bit is being forced off the intended path and is instead following the angle of the grain. I think Randymci's posting has some very helpful advise...Feed the bit slowly and clear the hole every quarter inch or so and see if that helps.

Another thought I had is that perhaps the bit is dull, which would make it more likely to be forced off course and follow the grain, or else the bit may have been sharpened asymmetrically and is cutting more agressively towards one side.

Best of luck...

Ed
Idaho Panhandle
MkV 505 etc

john · Post by **john** » Thu Jan 10, 2008 4:49 pm

all of the above is good advice but if I can offer one more suggestion, it is to secure the rip fence if you are using it as backup. I have noticed some deflection on my 510 rip fence when using to back up my work in the horizontal boring mode. It is even worse if you have a dull bit.

I now place a clamp behind the back end of the fence so it cannot move backward when applying pressure with the drill bit.

Good luck.

John

charlese · Post by **charlese** » Thu Jan 10, 2008 5:00 pm

john wrote:"...I have noticed some deflection on my 510 rip fence when using to back up my work in the horizontal boring mode. It is even worse if you have a dull bit..."
John

Wow John! That just shouldn't happen! Did you tighten up the adjusting lock nut (515286) to tighten up your outfeed clamp?

gbflora3 · Post by **gbflora3** » Thu Jan 10, 2008 7:55 pm

Thanks for all the helpful suggestions. I am drilling into the end grain. Starting with a 1 3/4 inch Forstner bit 2 inches deep. Then switching to a 1 inch Forstner bit for the rest of the way. I started on slow speed and increased it to 800 rpms when I switched to the 1 inch bit. The feed was slow and yes, I did clean out the chips often. I used the fence for support of the stock. I haven't checked all my alignments but will do that first. I suspect that my fence is deflecting a little bit also because the bit seems to be always going downward in the stock. Thanks again to all. Really appreciate the help.

Gary

nuhobby · Post by **nuhobby** » Thu Jan 10, 2008 9:13 pm

John, Chuck,

Please keep us posted on the fence-flex on the 510 when horizontal boring (I have encountered this at some times). Lately I have noted that the nice Shopsmith material on the "Song of the Great Lakes" banjo-making website includes a 510-->520 update section. In this case he liked the new 520 fence for the increased rigidity during horizontal boring.

Thanks

james.miller · Post by **james.miller** » Thu Jan 10, 2008 9:30 pm

Many years ago in the pre-traveling academy the instructor said to take a piece of wood that just fits into the miter slot and about 1" wide and slide the fence against it so it backs up the fence. I did this for a few years until SS came out with the 520 upgrade. The piece of wood has to fit fairly tight into the miter slot but not wedged in.

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