Squaring blank

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JCochrun

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Sep 13, 2010
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Penn Valley, CA
I have run into a problem. After inserting the tubes and allowing the glue to cure, I have been using a milling tool to clean any glue out of the tubes and the trim off any excess wood at the end of the blank and to square it up. My problem has been that I've been holding the blank in a clamp with one end of the blank resting on my workbench. I think the blanks were not square to begin with and when I use the milling tool, it make the end of the blank uneven. After assembly of the pen, I see a small gap between the end of the tubes and the band/end pieces. I do not have a belt/disc sander. Any suggestions to eliminate this problem?

I recently got a newer bandsaw. I had a 9inch Skill Band Saw and it's blade started turning as I cut, making all my cuts at an angle. I think this might have contributed to my problem. I now have a Central Machinery 14inch saw and it appears to be much better. At least it cuts in a straight line, not an angle. I am open to any and all suggestions.

Thanks,

Jim
 
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monophoto

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Mar 13, 2010
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Saratoga Springs, NY
Jim -

Are you saying that the tube extends slightly beyond the squared end of the blank? If so, I don't think that's uncommon - I've also experienced that, especially with 7mm tubes. I think that what is happening is that as your mill is trimming the end of the blank, it is also trimming a few microns off the end of the tube. But shaft on the mill is slightly smaller than the hole in the cutter, so what happens is that the cutter actually trims off the outer diameter of the tube leaving a very thin inner diameter that tries to slip into the gap between the shaft and the cutter.

This is less likely to happen with larger tubes because the shaft of the mill is stepped - the diameter of the shaft is larger than the hole in the cutter.

When I see this happening, I use a craft knife to chamfer the inner diameter of the tube and remove that slight extension.
 

bruce119

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Disk sander don't cost that much you can get a cheap one at H.F. and a set of punches. I just couldn't make blanks without them. I would never use a mill to square a blank. The only time I use a mill is to clean the ends after the blank was turned and finish just to clean the ends.

A picture is worth a thousand words.

sand1.jpg sand2.jpg
 

Lenny

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Jan 6, 2009
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Searsport, Maine
I'm not exactly sure what your describing... :confused:
The barrel trimmer SHOULD square the end of the blank provided you are using the correct size shaft. If, as Bruce suggested, you are experiencing the brass tube sticking out a little past the blank after trimming, that is pretty common (at least for me). I deal with it by using a countersink bit to chamfer the brass tube as monophoto suggested.
After the blank is finished and before assembly I use an old barrel trimmer with the shaft reversed and a piece of 100 grit sandpaper stuck to it (drill a 1/4 hole to fit over the shaft in a piece of adhesive backed sandpaper) to lightly sand the ends, This not only trues up the end but removes any CA that has wrapped over the edge of the blank. Oops... NewLondon beat me to it! :):redface:

An even BETTER option would be the special tool for this purpose that rherrell makes. Good Luck!
http://www.penturners.org/forum/showthread.php?t=42098
 

jttheclockman

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Feb 22, 2005
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NJ, USA.
Disk sander don't cost that much you can get a cheap one at H.F. and a set of punches. I just couldn't make blanks without them. I would never use a mill to square a blank. The only time I use a mill is to clean the ends after the blank was turned and finish just to clean the ends.

A picture is worth a thousand words.

View attachment 37265 View attachment 37266


OK Bruce. I see the jig. I like the jig but am confused. How do you hold the blank against the disc if the blank slides over the punch??? Are you holding the punch with the blank on it with one hand and then pushing the blank upwards with the other??? Doesn't the blank want to spin on you??? :confused:
 

Aerotech

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Jun 24, 2010
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Virginia Beach
you can also use a large metal bit, like a 1/2 or so to clean the brass off the end of the tube. i see it all the time with the 7mm brass.
 

Wildman

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Jan 12, 2008
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Jacksonville, NC, USA.
I install pen mill in bench top drill press, made a homemade drilling jig similar to Hut Pen drilling jig. Two pieces of 2x4 notched on both sides and a hinge. I do use a clamp on the jig to keep tight. I do adjust drill press table so can see when to stop.

The jig ensures blank is square to the pen mill. Does not matter if blank is absolutely square, area around the tube will be at end of milling process.

I also cut blank on bandsaw using homemade jig found in IAP library.

I could do same process on my bigger drill press and vise.

You can do same procedure on lathe if have a scroll chuck and drill chuck.

HUT Pen Drilling Jig
http://www.hutproducts.com/prodinfo.asp?number=0275

I bought a PSI jig for squaring up blanks on my belt sander, it works okay, just too much fussing around for me.
 

bruce119

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Disk sander don't cost that much you can get a cheap one at H.F. and a set of punches. I just couldn't make blanks without them. I would never use a mill to square a blank. The only time I use a mill is to clean the ends after the blank was turned and finish just to clean the ends.

A picture is worth a thousand words.

View attachment 37265 View attachment 37266


OK Bruce. I see the jig. I like the jig but am confused. How do you hold the blank against the disc if the blank slides over the punch??? Are you holding the punch with the blank on it with one hand and then pushing the blank upwards with the other??? Doesn't the blank want to spin on you??? :confused:

Sorry I was holding the camera with the other hand I only have 2 :rolleyes:. With one hand holding the punch tight on the corner molding and the blank on the punch that is extended to just about touching the sander. I use the other hand to gently push the blank onto the sander just taking off what is needed. After a wile you actually hear when you hit the brass tube and it's time to stop. Hope that helps it's the only method I use.

Bruce
 

Hucifer

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May 30, 2009
Messages
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Location
Asheboro, NC
I use my chop saw for cutting to length and squaring my blanks. PSI has a jig that I clamp to the bed of the saw. You slide back a stop and insert the tube then tighten the stop. I usually allow an extra 1/8. then insert the blank and tighten the clamp. The blank is then cut to length and the ends are perfectly square. I then drill and glue in the blanks. I deal with the extra 1/8th with a disc sander and another PSI jig. Although I do Like Bruce's jig with the punch set as it eliminates the need for sleeves...
And I will say that the punch set is worth it's weight in gold...

Having a square end on the blank to start has helped me significantly for my entire process... and I haven't found anything that is as efficient as this process.
 

Hucifer

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May 30, 2009
Messages
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Location
Asheboro, NC
El Snippo -
Sorry I was holding the camera with the other hand I only have 2 :rolleyes:. With one hand holding the punch tight on the corner molding and the blank on the punch that is extended to just about touching the sander. I use the other hand to gently push the blank onto the sander just taking off what is needed. After a wile you actually hear when you hit the brass tube and it's time to stop. Hope that helps it's the only method I use.

Bruce

I'm with Bruce - it's the only method I use as well. It also let's you rotate the blank slowly so if there is a minute difference in square it corrects it with the rotation...
 

aggromere

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Mar 27, 2009
Messages
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Tampa, FL
Just a thought. I drill and square on the lathe. You can try putting the blank in a 4 jaw chuck or a collet chuck and use a skew chisel (sharp) and square up the blank. I too sometimes have a little bit of tube sticking out of the blank. I just take that off with the skew chisel while im squaring the blank.
 

rherrell

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Aug 22, 2006
Messages
6,333
Location
Pilot Mountain, NC
I have run into a problem. After inserting the tubes and allowing the glue to cure, I have been using a milling tool to clean any glue out of the tubes and the trim off any excess wood at the end of the blank and to square it up. My problem has been that I've been holding the blank in a clamp with one end of the blank resting on my workbench. I think the blanks were not square to begin with and when I use the milling tool, it make the end of the blank uneven. After assembly of the pen, I see a small gap between the end of the tubes and the band/end pieces. I do not have a belt/disc sander. Any suggestions to eliminate this problem?

I recently got a newer bandsaw. I had a 9inch Skill Band Saw and it's blade started turning as I cut, making all my cuts at an angle. I think this might have contributed to my problem. I now have a Central Machinery 14inch saw and it appears to be much better. At least it cuts in a straight line, not an angle. I am open to any and all suggestions.

Thanks,

Jim

I make a tool that will eliminate that problem, you can read about it here.......
http://www.penturners.org/forum/showthread.php?t=62831
 
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