Is it possible to buy a metal hoop?

[dvddvd]

I'm planing on building a spray booth rig for spraying guitars.

I was planning on using 20mm steel conduit.

I've found a pillow bearing flange/ base for the base plate.

Then I was going to bend some steel conduit into a large u shape with a 90 degree where it goes through the base plate.

I wanted a 400mm round wheel/hoop at the bottom so I can turn the piece while I spray the body..

Is there any pre made metal hoops that I could use that can be welded onto the conduit?

 

[dvddvd]

 

[dvddvd]

A bit like this but instead of the D shape handle on the bottom a circular hoop.
How easy would it be to bend a perfect circle in 20mm conduit with a manual pipe bender machine?

 

[ChaiLatte]

How easy would it be to bend a perfect circle in 20mm conduit with a manual pipe bender machine?

It would not be possible. The best you might get is two individual, separate bends just over 180 degrees, but full circle, no.

All conduit benders use a former, so whatever bend you get will be the radius of the provided former. You can probably look up (or go to a local multistorey carpark and measure) what that radius is for 20mm conduit but it will be smaller than 200mm.

Look at a picture of one and think about what you see and how you would proceed. You need a straight length projecting from the end of the conduit to hook under the part that resists the bending force. Once you have pulled the first 90 or 120 degrees of the bend, how do you slide the conduit forward to hook back under that part to pull the remainder of the bend?

https://www.angliapipetools.co.uk/p...bender-20-25-mm-hilmor-el25-parts-compatible/

For a full circle, a 3 roll bender is the tool, and you need to buy wheels for it that accommodate 20mm diameter material (the 3/4" ones below would probably be OK).

https://stakesys.co.uk/rb38-3-roll-bender

If you have more time than money, you could copy that one using some 3D printed wheels, some bearings and a scissor jack all mounted between two stout pieces of wood (e.g. kitchen worktop offcut). I have also seen pictures of someone mounting two rollers to the bed of a milling machine, using the spindle as the third roller and the Y-axis to put on the squeeze.

I would be tempted to cut a plywood circle a bit smaller than the ID of the finished ring, fill the tube with kiln dried sand (ends capped) and pull it around the circle, restraining it from lifting as you go. You will need to go maybe 125% around the circle as the two ends will not bend.

Edit:

https://www.smythstoys.com/uk/en-gb...ts-basketball-hoop-wall-mounted-45cm/p/233755

Hacksaw off the excess and file smooth. I think it could be 450mm.

 

[Chief Sawdust Maker]

Have you got a good exhaust fitting shop near you? Not one of the big chains but a local specialist
We have a local one and he has a cnc pipe bender and will make stuff to order in mild and stainless in a wide range of diameters

 

[ChaiLatte]

Have you got a good exhaust fitting shop near you?

I have not seen many 20mm diameter exhaust pipes. The boy racers around here tend to go for 5".

A CNC bender will not do a full circle because it has to grab the pipe in the same way as a manual bender. A full circle has to be rolled. For superb exhaust bendsmanship, please see lancethegass on Youtube.

 

[Amplidyne]

You can bend 20mm conduit with a long piece of hardwood, with a slack fitting 20mm hole through it, and a bit of a radius rasped on the hole. A side piece off a pallet perhaps.
You bend the conduit by putting it through the timber, put one of the timber on the ground, and bend the conduit a little at a time, moving it through the bending block as you do it. It's how we learned to bend conduit as apprentices.
Draw the required bend on the floor. It's possible to make quite a good job of it.
You can even bend quite a tight circle. I have one here from long ago that I did to house a fish tape for conduit. I guess that if you offset the bend slightly you could bend a circle as a spiral, cut it off, and bend it back into a circle.

 

[Chief Sawdust Maker]

I have not seen many 20mm diameter exhaust pipes. The boy racers around here tend to go for 5".

A CNC bender will not do a full circle because it has to grab the pipe in the same way as a manual bender. A full circle has to be rolled. For superb exhaust bendsmanship, please see lancethegass on Youtube.

I didn't comment on any exhaust pipe being 20mm,

The majority of CNC benders can manipulate a wide range of size tube
With regards to CNC's and bending a full circle that would depend on the type of CNC and how it actually bends.
If the machine is capable of freeform bending i.e. it can bend a bend stright after a bend without a stright section then it can bend a full circle, the limitation being on pipe diameter pipe material and the desired bend radius.
CNC benders have various options for pipe clamping and do have to grab the pipe the same as a manual bender.

I was offering a possible solution based on experiance however I will get my coat!!!!

 

[Duncan A]

Ask a blacksmith if they can do something

 

[ChaiLatte]

I didn't comment on any exhaust pipe being 20mm...

Who wrote "Have you got a good exhaust fitting shop near you?" above?

An exhaust shop will have a machine that suits the type of work and the diameters of pipes it bends every day.

Why would they spend the money on a set of formers suitable for such small diameter or a machine that does a full bend if no customer ever in five years asks for that service?

If you walk into your local Kwikfit with the rear wheel off a tractor, they will be unable to assist you because although their business is snapping wheelstuds changing tyres, and they have machines that do this, the service you request from them with is not within their standard capability.

 

[Jake]

I think ring rolling would be the process you would need to achieve a hoop (a few years ago I had some 1" brass angle ring rolled into 1.2m circles for mirror surrounds).

But I don't see why the circle helps over a square with elbows at the corners. Or just some wood (and maybe a lazy susan bearing) and bolt something like this to it as the base.

Edit: Oh I think I get it, the hoop is a handle. How about a bicycle rim? BMX would be about that size.

 

[mwinfrance]

Morris marina steering wheel from a breakers is roundish..Almost any other steering wheel is actually round, some are small and might do for what you want.Actually , if it is to replace the D shape, bigger diameter of the "stand" is probably better..Motor bike wheel, or steel car wheel with hub , so it would turn ? There are also some stands for hanging garments that are used in shops that have large tubular metal circles at top and bottom, some already "spin" so that the customer can turn the garments on their hangers towards them.Shop fitters will be the place to try, keep both top and bottom rings and the vertical pipe bit, so you can hang other parts to be sprayed and turn as required.Here one would cost you about €50.00 and upwards, new.

I used to use an old one ( shop display carousel stand , chromed steel tube tube circle at the top and bottom ) for hanging tanks and small parts from back when I had a custom painting business. you can clamp things , or extensions to the top rings too.Just make sure that it isn't out of balance or too top heavy so it won't fall over.

 

[Chief Sawdust Maker]

I

Who wrote "Have you got a good exhaust fitting shop near you?" above?

An exhaust shop will have a machine that suits the type of work and the diameters of pipes it bends every day.

Why would they spend the money on a set of formers suitable for such small diameter or a machine that does a full bend if no customer ever in five years asks for that service?

If you walk into your local Kwikfit with the rear wheel off a tractor, they will be unable to assist you because although their business is snapping wheelstuds changing tyres, and they have machines that do this, the service you request from them with is not within their standard capability.

I repeat my earlier comment I made no reference to 20mm exhaust pipe, I referenced that an exhaust shop may have a CNC Bender

Depending on the type of machine formers are not always required bending is carried out by the positioning and movement of rollers

The comparison with Kwikfit and tractor tyres isn't really valid not all tyre and exhaust companies can do all types of work the same as they cant supply all makes of tyres.

I simply suggested that a local exhaust shop may be able to carry out the required bending, I didn't state that the exhaust shop would be able to do it but offered it as a suggestion I thought the whole idea of the forum was for people to try to help others based on their knowledge or experience, my experience being that an exhaust shop I have used for over 30 years doesn't just bend exhaust pipe

 

[Cabinetman]

So all you need is a base that spins? Lots of ways to do that. And no conduit would need to be, well anything!

 

[dvddvd]

Thanks for all the answers..

The basketball hoop looks good but then I thought still got to make some spokes and a hub etc.

I watched a lot of ring roller videos and it seems a slow process. Apparently using round tube and rod can be troublesome as it twists in the rolling process so doesn't come out flat..then I would need to weld it etc.

So had the idea of still using steel condiut for the main body and use a manual conduit bender to bend the shape of the main body.

But instead of using a hoop as the handle to spin it, use 4 rods that come out of the condiut at 90 degrees with a ball on the end of each one...I could drill and tap the main body of the conduit and say use 5mm rod for the handles

This is the base for spinning it