How close is ....close enough?

[tbfoto]

I'm working on a couple of Woodturningz slimline fancy pens. The cap, centerband and end all measure out with my calipers to be .335 in.
How close will you turn down your material when making a pen? I turned these down then applied ca but now realize they measure .350. Would .350 be close enough including finish or would you turn them down more and refinish? I don't want to press the parts on then have to deal with trying to take them apart.

 

[RBcarving]

In my world, .015 (1/64" or thickness of about 5 sheets of paper), would be quite apparent on a pen. I try to get higher end pens within .003" or better, but the cheaper the pen, the less time you would want to spend doing so. Typically you will turn your wood a little undersized and then finish a tiny bit oversized, then polish to fit. Just practice & getting the "feel"
Brad

 

[longbeard]

When i'm finishing a wood pen for a ca finish, i always turn the blank down a few thousands under, so when i put the ca finish on, i build it up to size as the component to give it a smooth transition from blank to component.

 

[Dale Allen]

Originally, I struggled with the same issue. And put them together anyway. Some got taken apart and reworked.
The one spot it will be the most noticed is at the writing tip end because that is both sight and feel.
Try this, put the writing tip on one of the blanks that measure .350" but do not put the transmission in. Turn down a short piece of wood that you can use to joint the 2 blanks and hold it like you would be writing with it.
.....Then 'you' will know how to proceed!

 

[robutacion]

I'm working on a couple of Woodturningz slimline fancy pens. The cap, centerband and end all measure out with my calipers to be .335 in.
How close will you turn down your material when making a pen? I turned these down then applied ca but now realize they measure .350. Would .350 be close enough including finish or would you turn them down more and refinish? I don't want to press the parts on then have to deal with trying to take them apart.

Geerzz mate, how long is a piece of string...???:wink::biggrin:

I know a few guys that have turned the new bushing for each kit down at least .025, as they use the same finish (layers of CA) and they worked out (measured) that their average CA thickness is just that so, instead of turning the barrels under and blunt the tools a lot more frequently by running into the bush's edge, they find this process a lot quicker and easy on the gouge(s).

New bushing untouched (not re-sized) will loose their square edge very quickly, particularly if using carbide tipped tools so, buy re-sizing them to what they need, these bushings last a long time.

Many customers request a natural finish and in this case, these re-sized bushing will be no good, this obviously require, for one to have 2 sets of bushings for each kit to accommodate all types of finishes and their thickness's...!

Hope it makes sense...!

PS: Re-sizing bushes is not a job for any wood lathe, regardless of how you do it or what you use the adjust the size, it will never be accurate and you endup with an oval shaped bush and or all other odd shapes so, if you don't have a metal lathe, find someone that does...!:wink:

Cheers
George

 

[reiddog1]

I try to overturn my blanks by .005 when I CA finish. I apply 2 coats of thin, 8 coats of medium, then 2 coats of thin. This gives me plenty enough of CA thickness to sand down flat with 350/400/600 then buff with Tripoli/white diamond. Of course this may vary depending how heavy or light you are with each coat of CA. Hope this helps.

Dave

 

[tbfoto]

I'm working on a couple of Woodturningz slimline fancy pens. The cap, centerband and end all measure out with my calipers to be .335 in.
How close will you turn down your material when making a pen? I turned these down then applied ca but now realize they measure .350. Would .350 be close enough including finish or would you turn them down more and refinish? I don't want to press the parts on then have to deal with trying to take them apart.

Geerzz mate, how long is a piece of string...???:wink::biggrin:



Cheers
George

Doesn't make any sense but....whatever. :biggrin:

 

[edstreet]

There is this concept called feel. If you can feel the gap or difference between the two surfaces then you did it wrong. The goal is to get a seamless and no apparent difference in feel on all fittings.

 

[its_virgil]

In my world I'm not sure I agree. Those who purchase our less expensive pens deserve the same quality and attention to detail as those who purchase our more expensive ones.
Do a good turn daily!
Don

In my world, .015 (1/64" or thickness of about 5 sheets of paper), would be quite apparent on a pen. I try to get higher end pens within .003" or better, but the cheaper the pen, the less time you would want to spend doing so. Typically you will turn your wood a little undersized and then finish a tiny bit oversized, then polish to fit. Just practice & getting the "feel"
Brad

 

[Russianwolf]

My problem with this topic is that everything expands and contracts with temp/humidity. Some more and some less, but everything moves.

I can make a pen that is absolutely perfect in terms of the fit, set is aside in my case and come back in 2 months and I can feel the junctions.

I decided that it better for the blank material to be proud of the metal parts unless the parts were specifically designed to be proud (Vertex is one of those). You never want to feel a sharp metal edge.

 

[SteveG]

My problem with this topic is that everything expands and contracts with temp/humidity. Some more and some less... You never want to feel a sharp metal edge.

Because if this known "movement", which is much more pronounced with wood than most other common pen materials, it is my practice to under turn the wood blanks, and be very close to right on with resin materials.

If you have ever slid your finger across the barrel-to-hardware joint and felt the abrupt metal edge proud of the barrel, you will NEVER want to do that again. It 'screams' out "Cheap,Cheap,Cheap". Time to disassemble that pen and do something about it!

 

[mredburn]

Part of the answer lies in your tolerances for fit. I know several pen turners that leave it slightly proud and then round over the ends so there is no sharp edge. They are happy with that result. Will you sell the pens? Give them away? Slightly proud is way better than undersized. I am some what anal about fit and feel anything over .003 is unacceptable but will your Techniques and tools allow you to do better than .015?