Mandrels Home Made - Im here thanks to Krysia's Link

Ness · November 07, 2009, 04:27:19 PM

Hi Fin - do you do tube too? I'd like some 6mm.

Edited to say I've answered my own question!!.

..had a look at your link and I don't think I can blow shards with an exhaust pipe!!

Redhotsal · November 07, 2009, 04:49:50 PM

Yeah, I'm after tubing too - 4mm, 5mm, 6mm, 8mm, wall thickness is not important. Got to be 316
Nine inch lengths would be perfect!

Redhotsal · November 07, 2009, 05:09:18 PM

Quote from: Krysia on October 15, 2009, 10:41:44 AM

A mandrel is quite simply a rod of metal that you can make a structure on. Due to the temperature that the glass melts and the way that some glasses contain metals in them (this is what gives them their colours) steel is good because it has a higher melting point then the glass. The working temperature of glass is around 500-600. The melting point being closer to 600 and the point that you can actually manipulate the glass into shapes closer to 520. (roughly ) That said people have burned thorough the mandrels.

Sorry to be a pedant but I reckon the working temperature is nearer 800-1000C. Certainly the temperature of the minor flame is nearer 1600C at the bottom of the flame so the old mandrels need to take a lot of abuse. Mentioning no supplier but I recently had a batch of 1.6mm which even I burned through. I guess they weren't quite stainless steel!

Fin · November 07, 2009, 05:17:42 PM

Quote from: Redhotsal on November 07, 2009, 04:49:50 PM
Yeah, I'm after tubing too - 4mm, 5mm, 6mm, 8mm, wall thickness is not important. Got to be 316
Nine inch lengths would be perfect!

Actually we probably can buy in the Tube. This sort of tubing is used in the brewing industry

I take it your sizes are for the internal bore Dia (ID)

I will find out the details and get back to you

Ilona · November 07, 2009, 05:22:46 PM

I am after 4mm mandrels - I hope you do these

Fin · November 07, 2009, 05:33:47 PM

Quote from: Redhotsal on November 07, 2009, 05:09:18 PM

Sorry to be a pedant but I reckon the working temperature is nearer 800-1000C. Certainly the temperature of the minor flame is nearer 1600C at the bottom of the flame so the old mandrels need to take a lot of abuse. Mentioning no supplier but I recently had a batch of 1.6mm which even I burned through. I guess they weren't quite stainless steel!

1390 - 1440 °C is the melting point of 316L .... so yes you will cause the mandrel to fail if its over heated...

Out of interest has anyone ever tried useing a Tungsten Electrode for a mandrel?.... The length may be to short as they are just 7" long... But they are all ready cut to length AND CAN STAND 3440 Deg C

Fin · November 07, 2009, 05:34:52 PM

Quote from: Ilona on November 07, 2009, 05:22:46 PM
I am after 4mm mandrels - I hope you do these

I will find out on Monday

Redhotsal · November 07, 2009, 07:19:13 PM

No, sorry Fin. Everyone thinks in external diameter here - So we're looking for 4mm, 5mm, etc. OD. No on cares about ID!

I know of someone who uses tungsten but I think its more expensive.

The stainless mandrels are usually fine, especially 2.3mm and over, but you do need to be a little careful when handling thinner as they can burn through. To be fair - it's usually the beginners that manage to do this and for the great majority of instances burning through a mandrel is not usually an issue but the recent batch I had were quite "weak" and burned through easily, so I assumed they were just a crappier grade stainless.

BTW - They need to be stainless as opposed to steel or they go rusty under the bead release too quickly.

Krysia@No98 · November 07, 2009, 07:21:17 PM

Quote from: Redhotsal on November 07, 2009, 05:09:18 PM
Quote from: Krysia on October 15, 2009, 10:41:44 AM

A mandrel is quite simply a rod of metal that you can make a structure on. Due to the temperature that the glass melts and the way that some glasses contain metals in them (this is what gives them their colours) steel is good because it has a higher melting point then the glass. The working temperature of glass is around 500-600. The melting point being closer to 600 and the point that you can actually manipulate the glass into shapes closer to 520. (roughly ) That said people have burned thorough the mandrels.

Sorry to be a pedant but I reckon the working temperature is nearer 800-1000C. Certainly the temperature of the minor flame is nearer 1600C at the bottom of the flame so the old mandrels need to take a lot of abuse. Mentioning no supplier but I recently had a batch of 1.6mm which even I burned through. I guess they weren't quite stainless steel!

Not at all Sal, to be honest I was kinda surprised that no one had said I got anything wrong. But as a newbie if I got everything else right I will be very proud of my self and will request a gold star

Redhotsal · November 07, 2009, 07:26:58 PM

Heh - sorry to wade in....still, either way, if you put your finger in the flame it would hurt like hell!

Krysia@No98 · November 07, 2009, 10:50:02 PM

he he, from experience - only if you hold it there and I would say, that's not something you do twice unless your me