Cutting PVC and Plastic help please

[donnyfl]

The suppressors are for air guns which generate a lot less heat than real guns and legal in many states. It is legal in CA. Making them out of pvc is actually better in terms of legality because like you said, if you put this on a real gun, the amount of power and heat it generates will blow it right off. Air guns are not considered as a fire arm in many states and that's the key word. In Florida, you can shoot air guns in your backyard with no problem but if you do something wrong with a slingshot you can get in big trouble with the law. On the downside, air guns can be as loud as the real ones so a lot of guys purchase aftermarket suppressors or LDC (Lead Dust Collector) so that they can shoot their guns in their backyard without disturbing their neighbors.

I just ran down to my garage to take a few pictures of the blades that I've tried. The bottom one is 180T designed for plastic yet it still chips and not flush. Second picture shows the aluminum spacers which will hopefully be replaced by the pvc. Third is a picture I recently showed ChuckOrlando of my first Carbon fiber suppressor.

I see. Again, as many of us have mentioned, sawing is your best bet. Since you have to cut a multiples of them off the same stock, cutting as you are now with those chipped edges & sanding might not be worthwhile as the next piece would have the area that was chipped off, not sure how critical that is. I doubt you would want to just use a hacksaw but it should take that much effort to do. Do you have an air supply? Air saw is another option, you can get one cheap from HF.

Your cuts aren't coming out straight now & neither would be something else hand held. I assume you would want the faces square. If it were me & I didn't have a bandsaw, parting in the lathe & deburring with a scraper would be my next choice. Are you deforming them in you lathe because of the speed of because of the chuck? I have a 6 jaw so that takes care of that. Try slower rpm & less grip on the chuck (assuming it's a 3 jaw.

Perhaps investing on a horiz bandsaw might be worth it. It will cut cleaner & you can set the work stop so you can just cut, pull the stock out to the work stop & cut again, it would be the fastest way.

Just a thought, I know nothing about guns & certainly nothing about supressors (highly illegal in CA) but would PVC even hold up to the heat in repeated use?

 

[darkzero]

Haha, I totally missed the word "air". Amazing how real they look now than when they first came out. Very nice!

 

[newbydave]

I use a plywood blade turned backwards for cutting vinyl siding and have cut pvc pipe
with my mitre box without a problem. A steady feed rate is important. Make sure saw
blade is up to speed before starting the cut.
Dave

 

[hman]

When I need to make a very clean cut on a piece of PVC pipe, I use my table saw. Unlike a miter saw, a table saw lets you keep an eye on the actual cutting area, and it's a lot easier to control the feed rate.

Be sure the blade is pretty new, or at least known to be nice and sharp. Carbide tipped, of course. If you hurry the cut, you'll often have a bit of a tab on the cutoff part. But if you slow down the feed (ie, the rate of "push") when you get to the end of the cut, there will either be no tab, or else the tab will be easy to simply snap off cleanly by hand.

If your table saw's miter gage is short, attach a piece of wood to it, so the pipe is supported all the way to the blade.

 

[Ebel440]

Is the pvc old it looks a little yellow in picture if so it could be brittle from age and more prone to chipping.

 

[donnyfl]

Good morning Ebel. I've cut a bunch of pvc tubes practicing and they all resulted the same. I started to use scrap ones I have laying around for further testing. That particular one was used outside to stake something short term. I use well water to water my backyard "fruit trees, veggies". It has a lot of iron so it gives a yellow stain. In front of my house we use reclaimed water. We are suppose to use reclaim for whole yard but I can't water my veggies with that. Good observation

Is the pvc old it looks a little yellow in picture if so it could be brittle from age and more prone to chipping.

 

[Rbeckett]

I'M a Air gunner also. I have a .177 Nitro venom, a .22 Umarex Octane and a .177 Webley Raider PCP. I would love to get off line and talk about your suppressor design because I really need one for the Webley because it has a definite sonic crack that caries a long way. Even though I live in the country I don't want to worry my neighbors with the sound of a rifle next door... the Webley is really a Hatsan AT44 in disguise and has the 1/2 fine thread barrel that will accept a standard suppressor with no problem. Drop me a PM when you have the time. And you stole my idea of using my machine tools to make suppressors for sale too!!!!

Bob

 

[KMoffett]

To me it looks like you are leaving the cutoff ends unsupported/unclamped as you cut through. They will tilt if unsupported and chip like that. If they are unclamped they will try to rotate as you cut through and chip. You will see that with any band saw, table saw, or handsaw.

Ken

 

[Fabrickator]

I've always used my chop saw and got good, clean straight cuts. Use a finer blade ( not a rip) and go through the finish slowly and you should get a clean cut.

I built a towable boat tailer (check you tube) out of 2 & 3" std PVC, seemed like a hundred cuts before I was done. It was more of an exercise in engineering, and it worked for off-road use.

 

[donnyfl]

Thank you everyone for your very clever solutions. I picked up this bandsaw this morning and it has been working great. I am sure it was user error for the other machines. Not doing at right speed, blade and etc. This one was very easy to get used to.




Bob I have to run some errands but will pm you later.