Stainless steel cores for drip tips

[whokrz]

First I would like to say that even though I am a supplier offline on this forum I am not starting this thread for personal gain, but to solve a problem.

Most wood turners do not have the ability to turn stainless on their wood lathe and are unable to make their own cores. I get requests for just the stainless core from wood turners on a regular basis. Unfortunately I make drip tips as a hobby and do not have the time or machining capability to supply the demand. Currently there is a demand for stainless cores and nonexistent supply. I would like to see this change so that fellow turners can have another project available for their hobby that is consistently available. I hope that the people in our vaping community can come together and find a solution.

The goal: A stainless core that will spin true between centers on a wood lathe.
Turning between centers allows the work piece to spin true on the lathe. Mandrels as a general rule do not spin the work piece true and a slight wobble is common. This wobble is undesirable when cutting up to the stainless connector and can be very hard on tools. For those that don't know what turning between centers looks like here is a link to a tip that I turned between centers. http://www.gentrywoodturning.com/howitmadeimgs/ecighowitsmade/IMG_3567.jpg

I have some experience on wood lathes, metal lathes and cnc lathes, but I am by no means a expert. I will describe how I make a stainless core with the problems and solutions I have found.

I made the first stainless core by chucking 3/8" 303 stainless rod into my metal lathe. I drilled a 1/8" hole for the air way, turned the outside of the tube down, turned the connector down, cut the o-ring groove and parted the core. The core was perfect until I put it between centers on my wood lathe and instead of spinning true the core had a wobble. When drilling the bit wanders slightly which causes the air hole to not be perfectly centered in the connector. This is not noticeable on a finished tip but is very noticeable between centers on a lathe.

Once I understood the problem I chucked the stainless, drilled the hole, turned the tube and parted the core. Then I chucked the tube section of the core into the lathe, brought up the live center and turned the connector. This method compensates for the drill bit wandering and allows the connector to spin true between centers.

Using a cnc lathe to turn cores that will spin true between centers has the same problems with the drill bit wandering and would require chucking each core individually. This extra step greatly slows down the cnc production and would increases the final cost.

Turning just the connector and then pressing fitting a stainless tube may create a core that will spin true. With the drilling distance being much shorter I don't think the drill bit wandering would be a issue.

Casting or forging may also work, but I don't know if either of those methods are capable of creating a core that will spin true and have a tolerance within a few thousandths of a inch.

If you have any ideas for core design, production or would just like to see stainless cores available please take the time to post.



Thanks
Lewis

 

[malkuth]

As a test, I ordered a couple of inserts from Pink Mule (in Spain). It is about a 2 week shipping time. I was not happy with what I received. The standard inserts are extremely short (~3/8") in my opinion. That means (for me) that the insert will only go up into the drip tip about 1/2 way. However, it has provided me with a pattern I can take to other people who are able to turn metal. I will keep everyone informed.

Sam

 

[Zanderist]

misunderstood, disregard.

 

[whokrz]

It is to bad they are so short especially for turners that are working with wood. Some species can cause the user to have alergic reactions unless the air way is completely sealed.

If you are intetested I can turn a core on my manual lathe and mail it to you. The ones I used to make are about 1.5" long, air way is 1/8", tube is .185, connector is .336 and oring groove is .230. This is the type that spins true on a wood lathe.

Sent from my LG-D801 using Tapatalk

 

[chabos]

So I've been trying to figure this out and happened to stumble upon this thread. Sorry for the semi noob question, but what exactly is the point of stainless steel cores in drip tips as opposed to straight wood or stainless? Is it purely cosmetic?

 

[malkuth]

So I've been trying to figure this out and happened to stumble upon this thread. Sorry for the semi noob question, but what exactly is the point of stainless steel cores in drip tips as opposed to straight wood or stainless? Is it purely cosmetic?

There are a couple of reasons for SS cores. Both are valid and (to me) have equal weight. The first one I mention is stability/durability of the tip. Without the core, the drip tip is fragile at the point where it is coming out of the atty. At that point, the walls of the tip are very thin (how thin is based on the diameter of the vape hole in the center). This is the point of least stability, and the tip is prone to break at that point. The second reason is sealing the inside of the wood. Without an insert, the vapor channel is difficult (if not impossible) to seal. You can use a pipe cleaner to put a layer of sealer on it, but it (IMO) is not sufficient to completely seal the wood. The wood can absorb the vapor as it passes through the tip. This can cause swelling of the wood, as well as making the tip impossible to clean. You will never be able to get flavors out of the wood, once they have been absorbed into the wood. Note that this is not an issue with stabilized wood, or acrylic materials.

As far as cosmetic issues are concerned, I prefer the look of the tip without the insert, personally.

 

[whokrz]

It also provides strengh for the neck of slinder tip. The tip in the picture above broke at the neck when it was dropped and the connector held. Bigscreend on this forum came up with the idea to put a stainless tube inside the wood which solved the problem. Then the connectors started to fail so I started to make those in stainless as well.

 

[cowjelly]

Are you talking something like this? Where your wood, acrylic etc. could be glued. then turned. Like pen turning?

 

[whokrz]

Yes, very similar to turning pens between centers. Where you glue the material on the core and turn it to the desired shape. It would be great to eventually see cores for sale at places like penn state ind and craft supply usa.
Here is a core that I made on my metal lathe, sorry I should have posted the picture earlier.

 

[cowjelly]

That's a good idea. The cost to machine would be better on a cnc. Setup and run a thousand or so. The end product would be nice and more durable than a typical tip for sure.

 

[whokrz]

Today I made a stainless core that spins true between centers for malkuth to show machinists. This is a one piece core and it requires the work piece to be chucked in the metal lathe twice so it will spin true on a wood lathe.

Then I started to play around with a press fit stainless core that would be easy to manufacture on a cnc lathe. I still had some 3/16OD 0.020" wall stainless tube that I used to use for making drip tips prior to the acrylic connectors failing. After a couple of tries I made the first press fit stainless core.

Bottom is a one piece core.
Middle is a press fit core with one o-ring groove
Top is a press fit core with two o-ring grooves (The connector on these are a little long for my DID)
Monday all three of these cores will be on their way to malkuth.

Tip of cores

Base of cores

This is the stainless tube cut to ~1.5" that I purchased on Stainless Steel 304L Welded Round Tubing, 3/16" OD, 0.148" ID, 0.020" Wall, 36" Length: Amazon.com: Industrial & Scientific

This is the connector prior to press fitting the stainless tube.
I made the connector by chucking a piece of 3/8 303 stainless rod into my manual lathe. I faced the rod to clean it up and center drilled. Then I used a #13 bit to drill in ~1/32. A #13 bit drills a hole in 303 stainless that is slightly larger than the 3/16 stainless tube. When pressing in the tube this helps get it started. Then I used a #14 bit to drill out the rest of the connector. Next I turned the OD of the connector to .335", made the o-ring grooves .230" and parted. After applying a little canola oil to the connector and tube I pressed them together with my vise.

As for the beer my favorite is Black Butte, but Mirror Pond will work for today

 

[malkuth]

My samples arrived yesterday. I must say I am impressed. They look very nice, and I love the dual o-ring cutouts. I will pass this on to the machinist that I am working with. It should be much more cost effective to use this method, rather than turning the entire insert.

 

[pt91]

Great news. Following this closely and appreciate your interest and help.

 

[whokrz]

Glad to hear you like how the cores came out and I hope all goes well with the machinist.

 

[Vapant]

They are looking nice.

Looking at the pic of the dual O-ring core, I got to thinking that if you got rid of the O-ring dividing wall and the top wall/flange, leaving a push fit tube with a single flange at one end, you could use the driptip material to create the shoulder at the other end.

Then only a sliver of stainless would be visible , and you would further reduce machining costs and reduce length.
Or am I missing something?

I was planning to just cast some Polyeurathane connectors that I could glue onto the same tube I would be lining my drip tips with, however I'd prefer stainless as I don't know how polyeurathane would react to the heat and juice in the top of an attie.

 

[malkuth]

I actually prefer the dual o-ring. They seem to be more stable. I happen to be one who picks up my Reo Grand by the drip tip, so I need all the stability I can get.

 

[Vapant]

I prefer the dual too but if they were shorter, they would fit more atties.
If the connector was single flanged you could choose single or dual o-ring when you are turning the drip tip part.

 

[whokrz]

They are looking nice.

Looking at the pic of the dual O-ring core, I got to thinking that if you got rid of the O-ring dividing wall and the top wall/flange, leaving a push fit tube with a single flange at one end, you could use the driptip material to create the shoulder at the other end.

Then only a sliver of stainless would be visible , and you would further reduce machining costs and reduce length.
Or am I missing something?

I was planning to just cast some Polyeurathane connectors that I could glue onto the same tube I would be lining my drip tips with, however I'd prefer stainless as I don't know how polyeurathane would react to the heat and juice in the top of an attie.

That's a great idea removing the o-ring dividing wall. When I get some time I will experiment with it and see if it will fit in my DID. I would recommend leaving the stainless shoulder so the turner doesn't have to turn the shoulder to ~.336". This would also be nice for turners that don't have calipers.

 

[Vapant]

True, also some less stable woods may expand and contract too much to be good for making a shoulder out of, plastics, stone and metals would be fine though.

Would it be possible to push two single flanged connectors onto the shaft/tube? either both the same facing (towards the mouth piece end) for single O-ring, or the top one reversed (flanges at opposing ends) for dual O-rings?

I would quite like to have the option for single or dual O-rings in one item but not if it is tricky to push fit two connectors onto the tube.

I would imagine the shortened dual O-ring version would be perfect for most though

 

[whokrz]

It should be possible to press two connectors onto a tube but it would make the connector really long.
I was thinking the machinest would press the connector onto the tube. Some people may want just the connector so they can make the tube as long or sort as they like then press in the tube. This would also save the machinist time. The only downside is if the tube bent in the vice it would be a real pain to remove the bent tube.