Best way to hold a brass tube while reaming?

[ndep]

I want to use an adjustable reamer to widen slightly a brass tube. I am wondering what's the best way to hold the brass tube while leaving my hands free to operate the reamer?

I think a simple bench vise might collapse the tube a bit. Are there other ways to do this?

 

[magpens]

@ndep

I do the reaming AFTER I have glued the brass tube into the blank material.

 

[jttheclockman]

I agree with Mal. With the blank you now have more to hold onto without collapsing the tube. Not sure what you are doing though

 

[ndep]

@ndep

I do the reaming AFTER I have glued the brass tube into the blank material.

So you ream after gluing but before turning?

 

[ndep]

I agree with Mal. With the blank you now have more to hold onto without collapsing the tube. Not sure what you are doing though

So ream before turning?

 

[jrista]

After gluing the tube in, before turning.

 

[magpens]

So you ream after gluing but before turning?

@ndep

Yes, that's right. . . I roughly round the blank, and while it is oversize I drill & glue in the tube. . Wait for the glue to set/cure for an hour or so.
I use 5-minute epoxy glue. . . I do worry about the epoxy holding because the reaming is quite a severe stress for the glue. . So far, so good !

Then the blank material acts as good support for the brass tube while you ream it.

After reaming, I then turn the blank down to the desired diameter and shape.

 

[magpens]

@ndep @jttheclockman

I'll just add the following ( since jttheclockman seems to question the reason for reaming ). MY reasons for reaming are as follows.

I sometimes like to avoid the usual "pressing in" of the pen kit parts. . The "pressing in" exerts outward stress on the blank material.
If the blank material, after turning, seems to be quite thin or fragile at the blank ends, I do the reaming and then glue in the pen parts.

Also, I sometimes like to "get the look of" the finished pen before the final permanent assembly. .
In that case I also ream and then glue in the parts.

The reaming process is also helpful if you are particularly fussy about aligning the pen parts with a pattern in the blank.
Sometimes the action of "pressing in" of the parts makes it difficult to get accurate alignment.
The reaming gives a looser fit for the pen parts and you can make alignment adjustment before the glue has set.

 

[jttheclockman]

Understood Mal. Is that the same reason the OP is wanting to ream?? I ream only if I see parts are too hard to press in. I would do it also when and if I do blanks like tigerwood or wood that is prone to crack. Taking any strain off is a good thing.

 

[magpens]

Understood Mal. Is that the same reason the OP is wanting to ream??

Thanks for your comments, John. . . I honestly do not know the OP's actual reason for reaming because he did not state it.

But I emphasized that the reasons I gave were MY reasons. . . I have long been wary of the usual "pressing in" process.
"Pressing in" expands the brass tube . . . not by much, but sometimes enough to crack the blank as I found out very early in my "career".

Also, to repeat, I sometimes like to "get the look of" the finished pen before final assembly . . . I do a trial assembly after reaming to check the appearance and the constraints that may arise from a desire to align the blank with features of the hardware ( including position of pen clip).
So I often do the reaming for alignment reasons . . . After checking appearance, I can disassemble very easily and then do the final finishing of the blank before the final assembly with glue.

Reaming does not remove very much of the brass tube and it does not take much effort to ream out about 3 or 4 thou. on the radius.
I think that brass tubes are typically about 10 - 12 thou in wall thickness. . . You do have to ream with care and to not overdo it.

As I recall, the 3 or 4 thou is about the amount that the pen parts are oversized with respect to the internal dimension (radius ?) of the tube.

 

[jttheclockman]

Mal more the reason I use epoxy to glue in tubes. It is flexible enough and can make up for those tight fitting components. Could also drill the blanks a bit larger to. Many way to get things done. Good luck.

 

[ndep]

Understood Mal. Is that the same reason the OP is wanting to ream?? I ream only if I see parts are too hard to press in. I would do it also when and if I do blanks like tigerwood or wood that is prone to crack. Taking any strain off is a good thing.

I need to ream so that cultured marble blanks don't fracture during pressing.

 

[ndep]

Thanks for your comments, John. . . I honestly do not know the OP's actual reason for reaming because he did not state it.

But I emphasized that the reasons I gave were MY reasons. . . I have long been wary of the usual "pressing in" process.
"Pressing in" expands the brass tube . . . not by much, but sometimes enough to crack the blank as I found out very early in my "career".

Also, to repeat, I sometimes like to "get the look of" the finished pen before final assembly . . . I do a trial assembly after reaming to check the appearance and the constraints that may arise from a desire to align the blank with features of the hardware ( including position of pen clip).
So I often do the reaming for alignment reasons . . . After checking appearance, I can disassemble very easily and then do the final finishing of the blank before the final assembly with glue.

Reaming does not remove very much of the brass tube and it does not take much effort to ream out about 3 or 4 thou. on the radius.
I think that brass tubes are typically about 10 - 12 thou in wall thickness. . . You do have to ream with care and to not overdo it.

As I recall, the 3 or 4 thou is about the amount that the pen parts are oversized with respect to the internal dimension (radius ?) of the tube.

I need to ream so that cultured marble blanks don't fracture during pressing.

 

[randyrls]

I will often expand a tube if using Corian. Corian is very hard and very brittle with no "give". It will crack when pressing in the fittings. I just take a transfer punch and insert it about 1/4" into the bare brass tube and spin it in a circle. I do this until the fitting just slips into the tube. I then glue, turn and finish as normal. I put a small drop of thick CA on the inside of the TUBE. Push the fitting in with a twisting motion. Leave the fitting alone for a few days to prevent "blushing".

 

[jrista]

I will often expand a tube if using Corian. Corian is very hard and very brittle with no "give". It will crack when pressing in the fittings. I just take a transfer punch and insert it about 1/4" into the bare brass tube and spin it in a circle. I do this until the fitting just slips into the tube. I then glue, turn and finish as normal. I put a small drop of thick CA on the inside of the TUBE. Push the fitting in with a twisting motion. Leave the fitting alone for a few days to prevent "blushing".

Just a small note here... I was talking with Ed from Exotic Blanks about this very issue, where fittings can often expand the tube and crack the blank. Ed also recommended finding some way to expand the tube, but mentioned that CA is not necessarily the best glue to use as it can react with some platings and ruin them. His recommendation was to use loctite instead. So far, its been working well for me, especially on Triton kits, which seem to have fittings that are just manufactured a bit too large to fit the tubes regardless (I've had cracked blanks with every material from the hardest resins to some relatively soft woods).

 

[Psychmike22]

So you ream after gluing but before turning?

Yes, I do this as well.

 

[randyrls]

Duplicate post.