Crack off machine.

**VertigoGlass** · 09-22-2010, 05:41 PM

I am thinking about building a crack off machine. I have seen a couple in person and the fab side of it would be cake work for me. I am wondering about the hydrogen torch that goes inside the tube and also the diamond bitthey use to score it, i assume its the same type of diamond bit that is used to dress grinding wheels. I dont want to pay 5-6k for one from a store when i can build all the frame work myself. I alrady have a supply of pillow blocks, steel, pulley, gears and stepper motors. Any info anyone wants to share would be great. thanks.

**Natedizzle** · 09-23-2010, 08:54 AM

If you build one for a reasonable price that works... I'll buy one... Been needing one for a minute now!

colonel4bin · 09-24-2010, 09:20 AM

You don't have to use hydrogen, I've always just used a national torch with a small tip. As for scoring you can use anything that will scratch it, maybe buy a blade for a scoring knife and mount it. I've seen a lot of different crack-off machines and most do the job well.

**HomegrownGlassStudio** · 09-24-2010, 10:01 AM

Hydrogen still will always get the best crack off it just gets hotter....

**VertigoGlass** · 09-24-2010, 10:12 AM

I don't want to build a machine that is going to go an ok decent or do the job well. I would stick to the method i have now if that was the case. I want the extremely clean precise perfect fire polished ends that a good crack off machine with hydrogen offers.

**Greymatter Glass** · 09-25-2010, 03:40 PM

Yeah the diamond would just be any decently mounted industrial diamond. A dressing wheel diamond would be perfect. You could also use a carbide point, less brittle, not as hard... fair trade off as any chatter in the tube might chip your diamond... I'm thinking a slow enough speed and a spring loaded cutter head would be enough to protect the diamond tho.

As for cracking off, the ones I have seen have the torches cross fired on the outside of the tube with an electric spark ignition... dunno if there would be an easy way to get it inside..... but it makes sense to do it that way.... seems like it would take longer to load the tubes, since you have to slide them off, not just lift out... *shrug*

Would love to see pictures of the build process if you get started on it!

-Doug

**Riley** · 09-25-2010, 04:04 PM

graffix had one they never used. it had the a single port torch that ran hydrogen. it had a long metal feed line that ran inside the tube. then it was just basically a couple sets of rollers with a motorized roller set to keep it going around. i'd imagine it would have had to have a sparker.

i'm not sure if you'd need the torch mounted inside, but maybe affects the overall performance ? anyhow, i didn't get a good study of their machine and i'd love to see what you come up with.

**nicko0** · 09-25-2010, 04:35 PM

diamond scribes arent too expensive. they can make that single smooth scratch

the tube torch that goes inside i think just has six tiny holes drilled radially in the end. premix.

**Flaming Balls** · 09-25-2010, 04:50 PM

Saw kimbles crackoff machine up close n personal. It had external torch n used water n just scored it in a small maybe 1" spot worked really nice

**Greymatter Glass** · 09-25-2010, 05:21 PM

yeah that'ss the style I've seen.... (external, water, short scribe)

The only way to light an internal torch would be an electronic ignition, or to flood the tube with the gas/air mixture, ignite one end, and let it propagate to the torch tips... would make one hell of a pop!

I've always wondered is a hot wire cutter would work on heavy wall tube.... I have the parts to make one, just haven't done it (yet).

**nicko0** · 09-25-2010, 05:26 PM

i think you just leave the torch on and just slide it in and out

**Adkins** · 01-12-2011, 11:57 PM

Are you still looking at building a crack-off machine because im selling one that is a crack-off and at other end is set up to make mouth pieces

**Riley** · 01-13-2011, 12:08 AM

i'm interested. maybe you could start a glassifieds ad, and drop some pics and a price so we can see whatcha working with.

**Adkins** · 01-13-2011, 12:23 AM

We have one going out tomorrow so ill post picture with this one you can cut glass and make mouth peice at the same time but with two people on one machine . That one goes for $3500

**mindblowingglass** · 01-15-2011, 10:55 AM

The new "jaws" mike will be releasing will make a cut off machine obsolete.

**boxfan willy** · 01-15-2011, 11:24 AM

booo to the thread jack! Inappropriate...

I am def interested in the crack off machine

boxfanwilly@gmail.com

**Adkins** · 01-15-2011, 10:04 PM

here is a picture

**hwcglass** · 01-15-2011, 10:36 PM

I sure wish I had any idea what that thing does.

I know it's not worth time educating a non buyer but I really want to know.

Videos? Pics in action? Pics finished glass?