# which plastic tube is the best to build a non wooden dummy?



## martialit (Feb 7, 2021)

HI 
do anyone have knowledge and or xp on wich material would be best to use to build a non wooden dummy in kind of a plastic?
abs? pvc? cpvc? other stuff i dont know.?

i would use wooden arm maybe so the ube should be solid et not crack.

some material have thickness options like 40 pvc 80 pvc 120 pvc 

tx for your suggestions


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## jobo (Feb 7, 2021)

martialit said:


> HI
> do anyone have knowledge and or xp on wich material would be best to use to build a non wooden dummy in kind of a plastic?
> abs? pvc? cpvc? other stuff i dont know.?
> 
> ...


why dont you build one out of wood ?

i see building one out of pcv with wooden arms as being problematic,, where as using a wooden frame with pvc arms to be a lot easier


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## yak sao (Feb 7, 2021)

This is one of those things where you're better off spending more for a quality dummy because it will cost you more in the long run.
Cheaper alternatives break and you end up having to repair/ replace.

The dummies themselves aren't too much, what gets expensive is the shipping.
You may be able to find a local woodworker who could build you one or depending on where you live you may be able to drive and pick one up and save on shipping.


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## martialit (Feb 8, 2021)

hi 
well that is not really helping me on my quest hahaha maybe  we ll see where it goes
being problematic what do you mean by that ?
I wont use wood, it requieres to many tools, too long too expensive. 
As for breaking, what is your concrete experience with that ?

tx


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## jobo (Feb 9, 2021)

martialit said:


> hi
> well that is not really helping me on my quest hahaha maybe  we ll see where it goes
> being problematic what do you mean by that ?
> I wont use wood, it requieres to many tools, too long too expensive.
> ...


i mean if your trying to firmly afix a peice of wood in pvc pipe and then bang it, it will quickly become lose, in fact it will quickly become lose on its own because of the different expansion rates.

if you get a solid peice of pvc, then you have more of a chance, but that no lighter or less exspensive( possibly more exspensive) than wood and ive never seen such a thing though im sure it exists some where

if you use pvc pipe in to pvc pipe you can use adhesive  that effectivly welds it in place, im still not sure about its long term duriability, but at least it will be fixed to start of with

if you start of with round in section timber,  its not the hardest job to drill some holes and bang it together, making it look nice is a touch more difficult

i suspect buying one will work out cheaper in the long run


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## geezer (Feb 9, 2021)

martialit said:


> HI
> do anyone have knowledge and or xp on wich material would be best to use to build a non wooden dummy in kind of a plastic?



 I vaguely remember seeing plans available online. They called for the trunk to be made out of large diameter schedule 40 pvc which has pretty hefty walls, about 1/4 inch thick, I believe. The arms are turned hardwood which you can purchase through a number of martial arts suppliers online and have square tenons  that fit through square sockets cut into the central pvc trunk. 

If you are a Wing Chun student, you can probably find someone in your lineage to give you details about what your branch considers optimal. If  you're not a WC student, you can just experiment.


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## martialit (Feb 9, 2021)

geezer said:


> I vaguely remember seeing plans available online. They called for the trunk to be made out of large diameter schedule 40 pvc which has pretty hefty walls, about 1/4 inch thick, I believe. The arms are turned hardwood which you can purchase through a number of martial arts suppliers online and have square tenons  that fit through square sockets cut into the central pvc trunk.
> 
> If you are a Wing Chun student, you can probably find someone in your lineage to give you details about what your branch considers optimal. If  you're not a WC student, you can just experiment.


HI that is the direction i want to take . Instead of wasting by trial error, i want to find info of how well it went for other projects with thick walls. 
do you think you could trace it back this projet you saw? tx


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## jobo (Feb 9, 2021)

martialit said:


> HI that is the direction i want to take . Instead of wasting by trial error, i want to find info of how well it went for other projects with thick walls.
> do you think you could trace it back this projet you saw? tx


try google wing ch7n dummy in pvc

How to build a Wing Chun wooden dummy in PVC - 6DRAGONSKUNGFU.COM

i still think it will break, in fact so do they in the introduction


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## Eric_H (Feb 9, 2021)

Guess it depends on your funds available vs cost of your time, if I wanted a PVC dummy, I'd get one from here:

PVC Dummy (Body Only) | Little Raven

I've bought a probably 30 or so wasters for my wutang fencing club from them over the years. They produce great stuff.


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## ShortBridge (Feb 9, 2021)

I have a little bit of experience with this. My dummy is one that was imported from China and made from old temple pillars, so they were fully cured and it's really nice, but it cost me about $1,000 and we coordinated an order for multiple people and even multiple area schools and waited a good while, so shipping was reasonable. 

Another local sifu's students bought him a really nice one in a garage sale.  So it is possible to get lucky.

But, that's not what you asked about. I've seen a few PVC ones and they don't come close, but for practicing the form, they're useful. You're not going to be able to wail on them and expect them to hold up, nor will they give you the right feedback, but footwork, range, repetition of the form, it's not a waste of your money as long as your expectations are reasonable. I don't think the material is all that important, cutting the angles right for the arms will be.

I've seen advertised some "arms" that clip onto bags or a post and I think they would accomplish the same thing. I have a utility pole in my front yard and I've thought about mocking up some kind of arms and leg that I could affix to it so I could go out and run the form a few times and take down. I think it would work, but it would not enable me to train the way that I was taught to on a mook jong. 

One last example, regarding building a wooden one. The trunk is the problem. Arms and the leg are easier if you you have a lathe or they can be bought. The trunk is supposed to be hardwood and either dried in a very large kiln or aged for decades, so that it doesn't change size and shape. Cutting the slots at exactly the correct angles is very difficult and I'm not totally sure how it's done, especially in old hardwood. An student of my SiFu was a extremely talented cabinet maker, very in-demand and had a professional shop. He made one, but he used a softer and greener wood for the body and he wasn't able to figure out how to cut the slots for the arms correctly. They should be at very specific angles, though that does differ a bit by lineage, and larger than the appendages, so that they move in the slots as you express force on them. He didn't get the angles right and it sucks to do the form it as a result, you contort yourself into odd positions, which is essentially bad training. Also, because the wood was too soft, the shape of those slots has been rounding off over the years and it's getting sloppy. No one likes doing the form that dummy. Personally, if that's the best he could do, I think it's a long shot for the average weekend woodworker to do it passably well. Probably if he made a few dozen, assuming he could get the right wood and season it appropriately, he could do as well as anyone, but, getting it passably right on the right first was not how it played out for him. 

If you are a Wing Chun student has been taught the form and how to train on a dummy and this device will be your only mook jong, I don't think you're going to be happy unless you buy a proper one. If you're looking for something to practice the form on at home and you have access to a good jong at your club, it might be okay. If you're not a Wing Chun student who is being taught this form, but want a dummy to work out somehow, I'd look at one of the wall mount ones or bag mounted ones honestly. You don't have to say, I'm not trying to out you, but your profile was empty, so I just didn't have context. Feel free to PM me if you'd like to discuss and don't want to disclose publically. No judgement from me. 

Otherwise, hopefully something in there helped.


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## Flying Crane (Feb 9, 2021)

Save up and buy quality.  In the end, you will be happier.


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## wckf92 (Feb 10, 2021)

Eric_H said:


> Guess it depends on your funds available vs cost of your time, if I wanted a PVC dummy, I'd get one from here:
> 
> PVC Dummy (Body Only) | Little Raven
> 
> I've bought a probably 30 or so wasters for my wutang fencing club from them over the years. They produce great stuff.



Yeah Raven is awesome. Excellent products.


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## dvcochran (Feb 10, 2021)

martialit said:


> HI
> do anyone have knowledge and or xp on wich material would be best to use to build a non wooden dummy in kind of a plastic?
> abs? pvc? cpvc? other stuff i dont know.?
> 
> ...


ABS is stronger and more durable, especially across temperature ranges. It is usually black.
It warps when repeatedly exposed to direct sunlight. Is illegal is many construction/building applications.  

PVC is the most common, durable and usually white or red. Gets more brittle in cold weather. When is fails it usually fails big. Long cracks along the extruded direction. Only rated for fluid but it is used for low pressure air and certain gasses frequently. If you build something structural the thicker the better. At least schedule 80 and 120 would be better. 

CPVC is very brittle in comparison to the other two and, while cheaper, would not be good at all for your application. 

PVC and ABS are close in price but I do not remember ever seeing ABS is the thicker schedules. For me it would come down to whichever I could source the cheapest.


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## Danny T (Feb 10, 2021)

While I prefer wood dummies made of PVC Schedule 80 can do well. The thing is dummies aren't for hitting hard on but for fine tuning positioning in relation to the dummy and proper vectoring. So if you aren't going to be pounding on the arms or the dummy PVC can be a good economical option 'IF' made properly and mounted on a good stand.


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## martialit (Feb 23, 2021)

hi , seems interesting is the pvc empty or it has something inside the body ?
did you see cracks ever?


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## martialit (Feb 23, 2021)

HI yes i have had acouple classes a long time ago.
how important is it that the arms and leg are loose? vs fixed or screwed in?
would you happen to have a document with the angles i think i could aim right.


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## martialit (Feb 23, 2021)

dvcochran said:


> ABS is stronger and more durable, especially across temperature ranges. It is usually black.
> It warps when repeatedly exposed to direct sunlight. Is illegal is many construction/building applications.
> 
> PVC is the most common, durable and usually white or red. Gets more brittle in cold weather. When is fails it usually fails big. Long cracks along the extruded direction. Only rated for fluid but it is used for low pressure air and certain gasses frequently. If you build something structural the thicker the better. At least schedule 80 and 120 would be better.
> ...


Very usefull info htx


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## martialit (Feb 23, 2021)

HI Jobo, what do you mean by  become lose on its own because of the different expansion rates. the dummy will stay indoors so what do you mean, ?tx


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## jobo (Feb 24, 2021)

martialit said:


> HI Jobo, what do you mean by  become lose on its own because of the different expansion rates. the dummy will stay indoors so what do you mean, ?tx


i mean that disimilar material exspand and contract at very different rates so if it tight and the pvc expands greater than the wood it will become loose , pvc exspands and contracts quite a lot with heat, wood doesnt, wood exspands and contracts greatly with moisture content pvc doesnt.

so youl end up with either the hole getting bigger or the wood getting smaller or the hole getting bigger and the wood getting bigger by a greater amount which will wear the hole and make it bigger when the wood contracts again or  or some other vatiation

the net result will be that quite soon it will be come loose


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## Svarog (Mar 10, 2021)

My friend uses PVC dummy for decades. He runs a club and that dummy gets beaten 3 times a week for almost 30 years. So, buy PVC pipe with the thickest wall , build a frame ,which is fairly easy, you can easily find plans online and buy the arms although you could build them by your self. Many people will tell that material is very important , it must be this and that, but what is really important is that dummy is properly adjusted to your body profile, like position of the arms, heights ... material is completely unimportant. Wooden, PVC, metal ...they are the same from the perspective of the dummy's training proposes.  If you decide  to build dummy by your self, PM. me and i will explain how to adjust it to your body frame.


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## dvcochran (Mar 10, 2021)

jobo said:


> i mean that disimilar material exspand and contract at very different rates so if it tight and the pvc expands greater than the wood it will become loose , pvc exspands and contracts quite a lot with heat, wood doesnt, wood exspands and contracts greatly with moisture content pvc doesnt.
> 
> so youl end up with either the hole getting bigger or the wood getting smaller or the hole getting bigger and the wood getting bigger by a greater amount which will wear the hole and make it bigger when the wood contracts again or  or some other vatiation
> 
> the net result will be that quite soon it will be come loose


PVC expansion is 4 to 5 times more than metal or steel pipe.
ABS, PVC and CPVC pipe, like other piping materials, undergo length changes as a result of temperature variations above and below the installation temperature. They expand and contract 4.5 to 5 times more than steel or iron pipe. The extent of the expansion or contraction is dependent upon the piping material’s coefficient of linear expansion, the length of pipe between directional changes, and the temperature differential. 
The coefficients of linear expansion (Y) for ABS, PVC, and CPVC (expressed in inches of expansion per 10°F temperature change per 100 feet of pipe) are as follows: 
Material Y (in./10°F/100 ft) ABS 0.66 ABS Plus 0.500 PVC 0.36 CPVC 0.408 The amount of expansion or contraction can be calculated using the following formula: e = Y (T1-T2) x Lp h 10 100 e = Dimensional change due to thermal expansion or contraction (in.) Y = Expansion coefficient (See table above.) (in./10°F/100 ft) (T1-T2) = Temperature differential between the installation temperature and the maximum or minimum system temperature, whichever provides the greatest differential (°F). Lp = Length of pipe run between changes in direction (ft) 

Example: How much expansion (e) can be expected in a 60 foot straight run of 2” diameter PVC pipe installed at 70°F and operating at 120°F? Solution: e = .360 (120 - 70) x 60 =.360 x 5 x .6 = 1.08 inches

So for the application expansion should not be an issue. I think the variability of wood will be the bigger factor.


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## geezer (Mar 13, 2021)

dvcochran said:


> So for the application expansion should not be an issue. I think the variability of wood will be the bigger factor.



As the wooden arms are quite loosely fitted into the trunk using the mortice and tenon method, expansion and contraction are not really a problem regardless of whether you use wood, metal or PVC for the trunk. There is normally a significant amount of "slop" in the joints so that the arms can move. Wear and tear would probably be a greater concern than coefficients of expansion. Good thing too ....since my math skills suck!

BTW if the tenons wear and allow too much movement, the joint can easily be tightened with shims, etc. ...or, as I planned to do, slip a piece of bike inner-tube over the tenons for both a snugger fit and less noise. ...and maybe fewer complaints from my wife and neighbors (I had the dummy out on the back porch). Got a cool neighbor now, and my wife tolerates me, so I never got around to it. Been meaning to test the idea though ....maybe with some heavy duty rubber-bands?


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