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Cracked pen

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Melinda_dd

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Some time ago, last summer, I turned a pen from a diamond cut blank from styles and bates.... beautiful blank.

The pen was a simple slim line pen, and finished lovely, glass finish with CA and BLO. all good.
I've noticed today it has cracked. It's been in a pen pot. Any ideas

The only thing i can think is the pen pot sits around 1ft from a radiator?would this be enough to crack it? It was turned straight, no bulges or anything so is quite thin?
 

NikNak

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Can you remember if when you assembled it, it was a bit of a 'tight' fit..?

I've found that pens to assemble that just 'feel' a bit on the tight side when pushed together can often split the material you're pushing them into.... even tho there's a brass tube :shock:

Plastic normally goes straight away, but i've even gone back to wooden ones a day or so later only to find the ends (normally seems to affect the tip or top...) have a hairline crack in them if they were a little on the tight side.



Nick
 

Melinda_dd

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No I can't remember if it was tight... but most of mine are (I'm not the best at plugging the tubes to keep the glue out, and then when I clean them they still have a little glue inside)
it would make sense though... the stress of the fit... tension on the wood and all that.

I've turned loads of acrylics and none of those have cracked, but I haven't really done a huge amount of wooden ones

The crack is from the middle to the nib and just noticed a tiny one up the end end! :(
 

NikNak

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Not done any of these 'Diamond Wood' ones myself....

wonder if its a fault in the material..? i.e. delaminating maybe..? :?:



Nick
 

Jonzjob

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What is 'diamond' or 'diamond wood' please?

Are you using the correct size drill for the kits Melinda? I only use the Axminster Artisan kits and the correct drill for them is, if anything, slightly loose..
 

Hitch

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I had this trouble with a slimline one in ebony.
Made it, put it in the case, left it for a couple of weeks, then noticed a crack.
I assumed it was where it was bought from the garage into the house.

Latest batch, I have drilled the blank, bought it inside for a week or so. Now it needs the drill running through again, as its a bit tight.
 

Melinda_dd

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Jonzjob":33kueqsw said:
What is 'diamond' or 'diamond wood' please?

Are you using the correct size drill for the kits Melinda? I only use the Axminster Artisan kits and the correct drill for them is, if anything, slightly loose..
Hi, yes I use the right drill bit for all my kits.
It's like laminated slices at an angle? they call it colourwood these days

http://www.stilesandbates.co.uk/product ... HCLWPB_MST

Bringing them in for a while sounds like a good idea. think i might try that.
 

nev

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Has anyone had a problem with acrylics cracking? made a couple of pens earlier in the week from timberbits https://www.timberbits.com/amethyst-pol ... clone.html
Had to resharpen the skew every three or four cuts :shock: but got there in the end.
I managed to crack one during assembly :evil: but the other made it unscathed.
or so i thought! I noticed last night that there were now cracks appearing from the edges on both pens. #-o
so do acrylics expand/contract like wood?
correct sized drill bits,(tube can dropped into drilled hole) the only thing i did differently was i used araldite instead of the usual PU, would this have any effect?
 

Hitch

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Update on my theory..... re-drilled one of the blanks, after being inside for 10 days, turned it, but on assembly it split.
I was looking out for the problem, so was extra cautious to get it all lined up and pushed in straight.

But it cracked. :(

Only an ebony slimline.
 

jumps

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nev":39yovsfh said:
Has anyone had a problem with acrylics cracking? made a couple of pens earlier in the week from timberbits https://www.timberbits.com/amethyst-pol ... clone.html
Had to resharpen the skew every three or four cuts :shock: but got there in the end.
Nev, how do you blunt a skew on polyester resin?

Acrylics do not like getting hot, is there some way you are stressing it with cuts or finish?
 

nev

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jumps":s6pwn1ef said:
nev":s6pwn1ef said:
Has anyone had a problem with acrylics cracking? made a couple of pens earlier in the week from timberbits https://www.timberbits.com/amethyst-pol ... clone.html
Had to resharpen the skew every three or four cuts :shock: but got there in the end.
Nev, how do you blunt a skew on polyester resin?

Acrylics do not like getting hot, is there some way you are stressing it with cuts or finish?
Beats me :) Not had the problem with previous acrylics, so i am guessing this opal pearly thing is a bit tough :?
almost as soon as a cut (light), maybe two the length of the blank had been made , had to move to a fresh bit of the edge, then another etc and then back to the grinder :shock: otherwise it just rattled and bounced and polished.

I did use some friction polish for the final finish so maybe got it a bit too hot when applying that?
 

Melinda_dd

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I've made loads of acrylic pens and only time i've ever had cracks is if I over push when fitting the bits together.
Never had any crack after assembly
 

Bill Mooney

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When I mill the ends of the blanks I usually touch the ends of the brass tube with the milling tool which puts a burr on the inside ends of the tube making the inserts tight to press in. I remove the burrs with a small file rubbed inside the tube ends before turning & have no problem pressing in the inserts or cracking of the timber or acrylic.Hope this helps.
 

nev

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It wasnt me going mad! emailed timberbits about the hardness of the blanks , this is his reply...

Hi Nev

Thanks for purchasing the pen blanks.

The Poly Resin is much harder than the acrylics. You should use a roughing gouge instead of a skew.

Let me know if you have any further questions or need more information.

Thanks again for purchasing the pen kits, your business is very much appreciated.

Regards

David


i guess i should also have asked about the cracking :oops:
 
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