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Plastic Tubing having standard ID sizes?

Zahnrad Kopf

Zahnrad Kopf

Diamond
Joined
Apr 5, 2010
Location
Tropic of Milwaukee
Signal to noise ratio of google returns is too small to waste too much time so thought to ask here.

Where would one look for some manner of "plastic" ( Nylon, Acetal, Polypro, etc... ) tubing having "standard" ID sizes? By "standard", I mean 0.500", 0.750", 1.00", 1.250", 1.375", etc... with something in the 0.010" - 0.030" oversize range.

I am entertaining making some spindle liners for a turning center. Would like to avoid sizing the IDs if at all possible.
 
There is a technical difference between tubing and hose. Tubing goes by the OD measurement, and hose goes by the inside diameter. Might help you narrow the field which otherwise might seem to be a random mixing of dimensions without any logic. It also demonstrates why you cannot have your cake and eat it too :D
 
Limy Sami said:
Any help? PVC Pipe Size Dimensions Chart — FORMUFIT
Click to expand...

Hi guys. I was not clear... let me try to remedy that...

I am aware of how pipe is sized. And, I'm aware of what tubing is. And, I'm not sure why I'd want to use hose for spindle liners, but what I am looking for is to use something in a plastic family instead of steels. Hence, my search for whatever-you-want-to-call-it having a through hole of appropriate size for standard sizes of stock to pass through without binding made of some manner of plastic that is not brittle.

I have contemplated making a fast-n-dirty way to drill out plastic tubing to nominal sizes, but I'd really rather avoid making more work than necessary.

Bottom line is that spindle liners for this machine are not as ubiquitous as other machines, and when they can be found they want stupid money for them, or for having them made. So, we'll make some, but I was considering to make them lighter and easier to make by using plastic.

Clear as mud?
 
Zahnrad Kopf said:
Hi guys. I was not clear... let me try to remedy that...

I am aware of how pipe is sized. And, I'm aware of what tubing is. And, I'm not sure why I'd want to use hose for spindle liners, but what I am looking for is to use something in a plastic family instead of steels. Hence, my search for whatever-you-want-to-call-it having a through hole of appropriate size for standard sizes of stock to pass through without binding made of some manner of plastic that is not brittle.

I have contemplated making a fast-n-dirty way to drill out plastic tubing to nominal sizes, but I'd really rather avoid making more work than necessary.

Bottom line is that spindle liners for this machine are not as ubiquitous as other machines, and when they can be found they want stupid money for them, or for having them made. So, we'll make some, but I was considering to make them lighter and easier to make by using plastic.

Clear as mud?
Click to expand...

Is it OK if I don't answer your question if I describe what I did to address the same issue? :)

We made our liners out of 4130 tubing with aluminum donuts slid over the tubing and secured with set screws, and orings in grooves around the donuts to keep them in the drawtube. .058 (or .049) wall 4130 is pretty light and the ID is just a few thou. over standard sizes so it fits round stock real closely. It would also allow us to slide soft tubing/hose inside if we wanted noise reduction, but that hasn't been an issue. Our oldest one is 10+ yrs old and still in fine shape.

If you find the OD/ID plastic, I'd like to know the source too.
 
Mud said:
Is it OK if I don't answer your question if I describe what I did to address the same issue? :)
Click to expand...

Of course, Sir. :)

Mud said:
We made our liners out of 4130 tubing with aluminum donuts slid over the tubing and secured with set screws, and orings in grooves around the donuts to keep them in the drawtube. .058 (or .049) wall 4130 is pretty light and the ID is just a few thou. over standard sizes so it fits round stock real closely. It would also allow us to slide soft tubing/hose inside if we wanted noise reduction, but that hasn't been an issue. Our oldest one is 10+ yrs old and still in fine shape.
If you find the OD/ID plastic, I'd like to know the source too.
Click to expand...

And that is exactly what the plan is at the moment. :cool:
If I'm being honest, I'm still vacillating between Ally doughnuts and Nylon66 doughnuts. Otherwise, we've the exact same plan of attack. :) ( I assume you also used DOM instead of ERW for the obvious reason )

To be very honest, I've been wondering why one couldn't simply use doughnuts, solely... Installation not much unlike ramming the wad of a black powder rifle, just done at intervals of depth... I'm sure there's a good reason. I may even discover what it is...

:cool:
 
Zahnrad Kopf said:
( I assume you also used DOM instead of ERW for the obvious reason )

To be very honest, I've been wondering why one couldn't simply use doughnuts, solely... Installation not much unlike ramming the wad of a black powder rifle, just done at intervals of depth... I'm sure there's a good reason. I may even discover what it is...

:cool:
Click to expand...

We used seamless 4130 to get the thin wall and corresponding ID. Also it was on the rack here.
We've done donuts only also. Used UHMW. We've also made the donuts tight on the stock and loose in the drawtube. For one part of 1.125 hex we broached the ID with a tool made from the raw stock, then split it and it sprang closed to hold tight to the stock. You only need 2 sleeves for a 4' piece, they advance with the stock then pull off it at the end. You need to be able to retrieve them without taking the chuck off, when right you can just blow them back out with air to put on the next piece.

OT - We mounted a stock support to the floor outside the lathe to allow a 6' liner or a 6' piece of stock for some fast moving jobs.
 
If your prepared to do it its not hard to cast these in polyurethane rubber, get into the 90 shore hardness range and they will work very very well and hold up damn near indefinitely. Totally unaffected by oils or coolant. Molds nothing more than a rod and tube affair with a suitable end cap on one end and support to keep things centered, so long as the tube id is well waxed and the rod, they pull out with out too many bad words.
 
Aren’t liners cut on angle, and isn’t plastic, uh, “plastic”?

Do the math, get the thickness spot-on, and overlap the butts on a mandrel.

Then slice off the overlap.

ON EDIT:

Perhaps my understanding is flawed. Oh, well...

I now suspect the third party makers don’t start with a tube, but a reel of “ribbon”, wrapped on a mandrel, welded to form a small version of spiral duct, then the O.D. is finished to spec.

Spiral-Pipe-Web.gif
 
Zahnrad Kopf said:
To be very honest, I've been wondering why one couldn't simply use doughnuts, solely... Installation not much unlike ramming the wad of a black powder rifle, just done at intervals of depth... I'm sure there's a good reason. I may even discover what it is...
Click to expand...

Full disclosure, I haven't actually seen the system in real life, but the manual for my turning center describes a system they offered which was basically that. However it also uses spacers between the donuts to control axial position. So you would have spacers that just slip into the drawtube and have a thin wall and are used universally, then donuts with various IDs to match your stock. Load them up alternating between donut and spacer and then ram the whole stack together. Obviously that means you need some kind of lip at the chuck end of the drawtube to push against, and a removable means of providing the same at the other end (maybe bore a step into a big shaft collar, or put tapped through holes in some kind of draw tube extension that line up with the last donut).
 
Zahnrad Kopf said:
You've been using SMC tubing for spindle liners?????? Really? On what? Swiss? Seriously. Not kidding. Genuinely curious. Thanks.
Click to expand...

Bad suggestion, largest size is 1/2". The stuff is durable and stays flexible. Use it for paint gun air hose. Also use it as piping on sheet metal edges.
 
Would Delrin (acetal) tube work? McMaster sells that in various Imperial IDs, also Nylon. The length is limited to 5' but they can often special order custom material.
 
Zahnrad Kopf said:
Clear as mud?
Click to expand...

More than clear. You seek "tube" or "tubing", as a structural shape, if you will. But not "tubing", nor "hose", meant for fluid conveyance and sized to fit common couplings.

EX: Rigid lengths, but not continuous rolls or reels, of Acrylic, polycarbonate, Carbon fibre, FRP, Micarta are sold that way - to specific dimensions not generally relevant to families of either OD or ID "connectors" at all.

As simple examples, the tubes that space those cheap stackable molded plastic shelving units. Plastic railings. Picnic table umbrella shafts. Some types of furniture. Some may look like "plastic pipe" until one tries to substitute pipe for it and finds it does not fit.

But a few examples of "many":

All Round Tubing - Carbon Fiber & Composite Tubes

https://www.professionalplastics.com/?gclid=EAIaIQobChMItODTrcHu3gIVxpyzCh3PqQXLEAMYAyAAEgLSbfD_BwE

Share the sizes you seek, someone on PM probably deals with it every day.

CAVEAT: Many of the plastics used ARE candidates for cracking too easily, reinforced ones the reverse.
 
Zahnrad Kopf said:
Signal to noise ratio of google returns is too small to waste too much time so thought to ask here.

Where would one look for some manner of "plastic" ( Nylon, Acetal, Polypro, etc... ) tubing having "standard" ID sizes? By "standard", I mean 0.500", 0.750", 1.00", 1.250", 1.375", etc... with something in the 0.010" - 0.030" oversize range.

I am entertaining making some spindle liners for a turning center. Would like to avoid sizing the IDs if at all possible.
Click to expand...

This is not something typically available, at least as plastic tube from distributors in that business. The mills' typical product offering is going to be +/- .010 at best on tubing ID nominal size, and most of them will usually run to minus, so that you CAN size them;-) I imagine that this is what you have already seen from McMaster's offerings. Sometimes you can end up with a run of oversize ID's by luck, but it's a total crap shoot based on factory tolerance. You may be able to have your local plastic distributor check some IDs on their stock materials, and by extension, they may also be able to check with their suppliers to see if any have runs of material that are indeed oversize on ID. But it isn't especially common.
 
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