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View Full Version : Making dust pickups, adapters etc



Tom Bender
02-13-2018, 7:37 PM
My Dust Cobra has a 2 1/4" hose which I use to vacuum the shop and connect to machines as I use them. It came with a wand and a few attachments. Having spent years designing industrial dust collection, I am not happy with the dust pickups and other hose end devices. They are designed by hacks who don't test their product. So I made a couple, one from PVC pipe and one from stiff paper and wood. The PVC attachment for vacuuming the floor is better than the one provided but there is room to improve. The paper and wood pickup works great on the bench top for sanding and routing but is just a mockup. It should be more durable. The traditional plastic used is the right stuff but I don't know how to work with it. Any suggestions?

Jeff Robinson
02-13-2018, 8:42 PM
I believe the plastics for most vacuum attachments are injection molded. Those machines are tens of thousands of dollars so getting the same plastic doesn't seem practical unless you know someone who already does injection molding. I like your thoughts on the attachment modifications though with pvc. Any pictures?

Peter Christensen
02-13-2018, 9:28 PM
You could make a male mould the shape you want for best airflow etc., out of plaster, coat with mould release or wax and fibre glass it. Smash out the plaster when done. Or if the shape is more complex make the mould out of styrofoam and use epoxy to fibre glass it. When cured the styrofoam can be dissolved out with acetone.

Bill Dufour
02-14-2018, 12:25 AM
PVC can be heated and shaped over a form. It can also be glued easily.
BILL D

Charlie Jones
02-14-2018, 12:31 PM
I made several of my 6" dust collection fittings from PVC Sewer and drain pipe. Just heat the pipe until it gets soft. You can hand shape it with gloves or bend it around a form.

Tom Bender
02-14-2018, 7:04 PM
Fiberglass was what I was thinking but hoping for something easier.

I have tried bending PVC with some success, but it didn't seem promising for a new fabrication.

John K Jordan
02-14-2018, 7:37 PM
Fiberglass was what I was thinking but hoping for something easier.

I have tried bending PVC with some success, but it didn't seem promising for a new fabrication.

Tom, photos or drawings of your prototypes may trigger useful ideas for fabrication methods. JKJ

Lee Schierer
02-15-2018, 3:08 PM
3D printing can make pretty much any shape or contour. Most 3D printers use plastic so you could make a prototype that is more durable and exact than paper or cardboard. You would have to learn 3D design and the printers aren't exactly cheap. Some community colleges offer courses in 3D design and they may also have printers.

Malcolm McLeod
02-15-2018, 3:45 PM
3D printing can make pretty much any shape or contour. Most 3D printers use plastic so you could make a prototype that is more durable and exact than paper or cardboard. You would have to learn 3D design and the printers aren't exactly cheap. Some community colleges offer courses in 3D design and they may also have printers.

Some 3D printers can extrude several different plastics with varying properties, including fillers for strength - perhaps even durable enough for routine use?? Might be able to get a design fabricated by an existing 3D owner, or with/by a Makerspace group.

Not to rain of the parade, but I made a living at injection molding (...some time back:eek:), and while high volume production is relatively cheap, a ticket to the dance is steep. Guessing, but in today's dollars I'd bet a small injection molding machine (50 ton) might run $250,000 or more. Large machines (500 ton and up) would probably cost well into the millions. Tho' if you buy the mold(s) (maybe $100,000 for a small one..???), a contract molder might produce parts for you. IMHO, I'd think you need to get a pretty serious sales commitment before taking this 'ride'.;)

Any history buffs out there? I've not looked into the history of 3D printing, but I'd speculate that the very high entry cost of injection molding gave rise to 3D printing...?

Mike Null
02-17-2018, 2:14 PM
20+ years ago we leased a stereolithography machine for the purpose of prototyping parts. At that time I understand the cost of the machine was over $1 million.
That, I believe, was the forerunner of the 3d printing equipment of today. (watching that machine produce a part was something like watching grass grow)

Having been in the appliance manufacturing business, injection molding machines were in common use. Cincinnati Milacron made most of our behemoths.

Tom Bender
02-17-2018, 7:57 PM
Ok can we back up to a toy called vacuform? Some youtube vids make it look fairly easy. Would need to work with some heavier plastic or make multiple layers. Anyone done this?

Marc Jeske
02-19-2018, 6:55 PM
Seems to me I would google image search existing attachments by various companies, find what looks good for you, buy it, test it attached w tape or whatever.

If it works like you hope, you can easily make it fit to your hose or whatever w a bit of creative thinking.

Possibly using off shelf PVC plumbing pipe or fittings.

There are posts on this forum, plus a number of Youtube videos on PVC custom adapters using PVC glue and/ or heating.

Don't be afraid of the heating and re forming.. works great.



Marc

Tom Bender
02-19-2018, 8:03 PM
Actually I'm thinking of working in sheetmetal, as I have some experience there.

John Lifer
04-26-2018, 6:19 PM
Thread a Little old, but having just got a 3d printer, and as entry level at $150, it works pretty good. Then PLA material is decently rugged and there are a number of 3d hose fittings already designed and some of them have open source programming allowing you to input dimensions and make your own specialty. Size of print is a bit constraining, I can make up to roughly 200mm cube. As an old injection molding engineer, they are pretty neat toys.

Marc Jeske
04-26-2018, 8:19 PM
All should keep in mind "Old" threads archive as a collective brain , at least for those that understand the value of using Advanced Search, drilling down w poignant keywords.

Almost all of what we discuss here remains true for many years.

A WEALTH of info.

Always use Advanced Search here, and other forums when you need to quickly and efficiently learn a specific topic, and we should never be shy to resurrect an old thread unless it is time relevant, like a current Craigslist offering, etc.

Every contribution a member makes is for the Greater Good longterm to help us all.

Marc

Matt Lau
05-15-2018, 12:53 PM
Tom, can you draw what you have in mind?

I've been looking into this myself as 1.) I'm cheap; 2.) I'm using a shopvac (albeit very good shopvac) for dust collection.
I'm tempted to make one out of pine and shape it by rasp and chisel.

Jim Andrew
05-16-2018, 1:18 AM
You can make things out of plexiglass, cut it with a coping saw,or jig saw, just remember to make cuts slowly, bend it with a heat gun, and glue it together at corners with fiberglass resin.

Joe Rogers
10-01-2018, 9:53 AM
I know this is a stale thread but I have been making holsters out of Kydex. Kydex is a poly vinyl material that is supplied in sheets and is a thermoplastic. Heat in a toaster oven, regular oven ( if the wife allows...some odor ) or locally apply a heat gun until it reaches appooximately 325 degrees F. When plyable mold over a buck or by hand with gloves and cool quickly with a cold wet rag. Material is available in different thicknesses and is durable. It can be glued using pvc plumbing glue. If I needed a custom fitting, it is what I would use.
https://en.m.wikipedia.org/wiki/Kydex
Joe

Matt Lau
10-07-2018, 12:41 AM
Hey Joe,

Great idea!