# Squaring up polyester resin blanks



## badwin (Sep 11, 2005)

Recently bought  some resin blanks from Ed @ yoyo spin.  (Thanks Ed they look awesome)  Now for the question how do you square these blanks with the tube?  Don't know if you can use the pen mill.  Thanks in advance fo the help.  Thought I would post it here instead of asking Ed directly so that others could use the info.
Brian


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## coach (Sep 11, 2005)

I use a pen mill.  Works fine.


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## LAKingsFan (Nov 19, 2005)

You can use a pen mill or a disc sander. Be careful not to sand or shave the brass tube.

I use a pen mill on a cordless drill at med/fast speed. Don't push too hard when using the pen mill or you can crack the blank.

Good luck

Ron


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## wayneis (Nov 19, 2005)

I use a disk sander for everything but you can use a trimmer if it is smaller than the blank.  What you Do Not want is for the cutter head to be larger than the end of the blank because there is a very good chance that you will catch an edge and and break it off.

Wayne


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## alamocdc (Nov 19, 2005)

I've never had a problem using a pen mill on PR or acrylic.


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## ed4copies (Nov 21, 2005)

What Wayne said, plus SHARP!

Dull trimmer equals cracked blank.


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## alamocdc (Nov 21, 2005)

I must just be blessed! [:I] 5/8" trimmer + 3/4" blanks = no problems. Now I'm knocking wood! []


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## ed4copies (Nov 21, 2005)

Billy,

Your trimmer IS smaller than the blank, that's what Wayne is saying.  If the trimmer catches a corner it can remove it violently (or "blow it out"), leaving shatters where plastic used to be (not a good thing!!!)


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## alamocdc (Nov 21, 2005)

DOH! [B)] Read it wrong! Thanks for straightening me out, Ed! I'll be okay after a good month's sleep!


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## ed4copies (Nov 21, 2005)

HO,  HO,   HO!!!

Good month's sleep comes after Santa!!


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## Mikey (Nov 21, 2005)

FWIW, my pen mills never fit snugly inside one of the tubes of the baron or a Sierra even with a bushing. I have found that if I mark the place where a certain part of the tube sits when I drill it, I can easily fasten it back in the same location to square up the blank on the DP. (I don't have a sander yet.)

If anyone knows which sizes of barrel trimmers from AS work with the barons and Sierras, let me know and they'll be on my next order.


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## LanceD (Nov 21, 2005)

25/64 and 15/32 pen mills from AS or CSUSA fits the Baron tubes.


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## Mikey (Nov 21, 2005)

OK, thanks. One more question... If the tubes fit into a 25/64 hole that I drilled, do the 25/64 mills fit inside the brass tubes, or do you guys all mill the blanks before the tubes are glued in? (ie, are the mills actually undersized to allow common fitting dimensions to be used?)


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## alamocdc (Nov 21, 2005)

7mm and 10mm mills work inside the 7mm and 10mm tubes, so I'd guess that the others follow suit.


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## tnilmerl (Jan 12, 2006)

Woodcraft (and some other vendors too) have a new 3/4" trimmer with multiple shafts.  Should handle most kits.  

The only problems (to me at least) is that the shafts are NOT threaded.  Seems to be designed for chucking into a drill press for use.  The shaft end (for chucking) is too short by my standards.  Not confident that the mill will rotate true when chucked into a drill press.  For this reason, I prefer to square-up hand.  I have some older shafts with threads that I carved handles for hand use.

On the subject of the various tubes sizes for all the different kits, I turned sleeves for all the tubes out of some spare white corian I had laying around.  Wood sleeves are too brittle for thin sleeves, even when using a 7mm shaft.  I also make them longer that the metal sleeves you can buy.  I have a set of micrometers for checking that I am getting the sleeve down to the correct thickness.  When close, I stop using a tool and sand down to the final dimension.  I then mark the appropriate dimension on each sleeve with a Sharpie marker (i.e. 15mm, 31/64, etc.).  I have a box with a all the dimensions for the pens kits I turn on a regular basis.  If a new tube comes out, I turn an additional sleeve for the collection.

If you trim by hand, the sleeve is mandatory.  Using a mill that is not snug in the tube allows the mill to wobble and you do not get an exact 90degree trim on the blank, and it will be noticeable to the naked eye.  If you chuck the mill in a drill press, then you shouldn't have any wobble, and you 'may' be able to forego the sleeve.  I would test this before trying on a live blank.  You can chuck the mill in the press, scrap piece of lumber under the mill and lower the mill until the shaft touches the scrap lumber.  Rotate the chcuk and mill by hand and watch whether the shaft tip wobbles out of true.  If it does, then use a sleeve.

Some people sand the blanks square, but you have to either have the bore exactly perpendicular to the side you lay on the sanding table or you need a jig to hold the blank perpendicular to the sand surface.  Mostly of the jigs I have seen use a mandrel mechanism similar to the lathe setup.  For that, you would then need a sleeve to fit on the mandrel to keep the blank from wobbling on the sanding jig mandrel.  Same problem has a hand driven pen mill.

Several means to accomplish the same goal.  Pick the one you are most comfortable with and run with it.  All have their own advantages and disadvantages.


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## gerryr (Jan 12, 2006)

I use 1.5" masking tape to imitate a sleeve.  The good thing about it is you can make it fit as snugly in the tube as you like.  The bad thing is that you have to do it over each time you change to a different tube size.  You also need to wrap the tape in the same direction that the mill rotates.  DAMHIKT.


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## tnilmerl (Jan 12, 2006)

Now the tape idea sounds interesting.  But to save time, I think I'll get some 7mm tubes and wrap tape around them to make a more permanent sleeve.  Faster and easier than turning down a sleeve out of corian or whatever.

I have a roll of packing tape which is wide, not as thick as masking tape and more adhesive.  Worth a shot.  Doesn't have to be exactly centered, just snug.

Thanks for the idea!


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