I am planning on building the cyclone from Dec 2001 issue of best-ever
Workshops from Wood Magazine. It seems to me that I read somewhere that one
of the recommended enhancements was to extend the inlet pipe several inches
inside the cyclone cylinder to force the rotation of the airr current.
Unfortunately, all magazine and internet searches for this enhancement have
turned up 0 results.
Does anyone have a list of recommended changes to this cyclone?
Thanks,
Kevin Meier
On Fri, 31 Oct 2003 16:23:16 GMT, "Kevin" <[email protected]> wrote:
>I am planning on building the cyclone from Dec 2001 issue of best-ever
>Workshops from Wood Magazine. It seems to me that I read somewhere that one
>of the recommended enhancements was to extend the inlet pipe several inches
>inside the cyclone cylinder to force the rotation of the airr current.
>Unfortunately, all magazine and internet searches for this enhancement have
>turned up 0 results.
>
>Does anyone have a list of recommended changes to this cyclone?
>
>Thanks,
>Kevin Meier
>
I built a cyclone based on the Wood version a few years back. Since I lost my job I've been researching cyclones again with a view to making a living from selling them - no product yet though.
There are quite a few improvements that people have made to improve the Wood cyclone. It was a pretty rough design. The good news is that even rough designs work reasonably well. However, if you'd
like to build a better cyclone, here is my list of recommendations.
Use heavier gage galvanized iron. I used 26 gage and that seems fine to me. My local steel companies sometimes stock 26 gage but often the lightest they have is 24 gage.
Note: cyclones are described in terms of the diameter of the barrel. This dimension is called D. A 1D3D cyclone has a barrel that is as tall as it is wide and a cone that is 3 times the height of
the barrel. a 2D2D cyclone has a barrel and a cone that are both twice the height of the diameter.
The most efficient dust separating cyclones are 4D tall. Either a 1D3D or 2D2D design. The papers I've read consistently get slightly better but not statistically significant dust separation with a
1D3D. Many people consider 1D3D the best design.
So, if you have space, use a 1D3D cyclone. Bill Pentz claims that a 1D1.67D cyclone is a sweet spot for shorter cyclones.
Use a rectangular inlet. The standard dimension for a 1D3D cyclone (h x w)is D x D/8. However, there are studies that show better performance with a D/4 x D/2 inlet. The D/4 x D/2 inlet is also
less likely to clog than a narrower design. The dimensions also work out nicely if you use the vortex finder modification.
Use a bigger vortex finder. Bill Pentz (see link below) recommends D/2.
Use a shorter vortex finder. It needs to stick into the barrel down to at least the bottom of the inlet to prevent excessive short-circuiting (dust blowing directly from the inlet to the outlet
without spinning around). If it's too long (say down to the bottom of the barrel or longer) the air can have trouble making a smooth change of direction up the vortex finder. There is a CFD
(Computational Fluid Dynamic) model that shows a torodial eddy around the vortex finder just below the cylinder head. The eddy can carry dust straight down the side of the barrel and then straight up
the vortex finder. I'd make the vorex finder extend an inch or two below the level of the inlet bottom.
Use a neutral vane. IOW, extend the inlet into the barrel and end it on a radial plane that runs vertically through the barrel. This reduces the amount of energy required to run the cyclone. If
you're really particular, you can test your cyclone and slide the inlet in until you get minimal pressure drop. Once you find the optimal location, lock it down.
Use an air ramp. This is just a spiral ramp that starts at the top of the inlet and spirals down to meet the bottom on the inlet. This reduces the pressure drop of the cyclone.
If you have space for a 1D3D with height left over, use a downcomer tube. This is just a straight pipe between the bottom of the cone and the dust bin. It's the same diameter as the dust outlet.
The optimal length seems to be about D.
An alternative to a downcomer tube is to put a cone in the dust bin. The paper I read used a 90 degree apex angle cone about 10% bigger than the dust outlet. Both the cone and the downcomer tube
reduce the re-entrainment of dust from the dust bin. The additional pressure drop is about the same for both approaches.
Another approach is to use a vane, about one inch tall near the bottom of the dust outlet. This vane is just fastened to the cone wall. IIRC, the paper I found that in used a length of 1D on a 3D
cone. They reported that it improved collection efficiency. Unfortunately, I haven't been able to find that reference again. I suspect it works much as the downcomer tube does.
The bad news is that the modifications to improve separation efficiency increase the pressure drop. The downcomer tube costs about 20% more pressure drop. Using the D/2 x D/4 inlet in conjunction
with a D/3 dust outlet (about what Wood magazine specified) costs about 20%.
That means that it is important to use the modifications that reduce pressure drop. In particular, use a neutral vane. Bill Pentz reports that a neutral vane reduces pressure drop by about 30%.
On one of his spreadsheets, Bill Pentz estimates that using an air ramp saves about another 15% in pressure drop.
You can also make the cyclone a little bigger; running a 1D3D with an inlet velocity of 2,600 fpm costs less pressure drop than the standard 3,4200 fpm but does little to collection efficiency, it may
even help.
To keep the air flow up, you'll also have to make sure that you have nice smooth transitions and long-radius curves in your ductwork. You'll probably want to run 6 inch pipe.
And don't forget to get a big enough blower.
Whew! Sorry for the long post.
There is a wealth of information at Bill Pentz's web site:
http://cnets.net/~eclectic/woodworking/cyclone/
I posted some of my "lessons learned" after I built my first cyclone:
<http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=3b2d934f.21004476%40news.cncx.net&rnum=1>
Bob S
On 02 Nov 2003 22:02:14 GMT, [email protected] (Bob
Summers) wrote:
What would be the estimate cost for a 2 HP cyclone?
>On Fri, 31 Oct 2003 16:23:16 GMT, "Kevin" <[email protected]> wrote:
>
>>I am planning on building the cyclone from Dec 2001 issue of best-ever
>>Workshops from Wood Magazine. It seems to me that I read somewhere that one
>>of the recommended enhancements was to extend the inlet pipe several inches
>>inside the cyclone cylinder to force the rotation of the airr current.
>>Unfortunately, all magazine and internet searches for this enhancement have
>>turned up 0 results.
>>
>>Does anyone have a list of recommended changes to this cyclone?
>>
>>Thanks,
>>Kevin Meier
>>
>I built a cyclone based on the Wood version a few years back. Since I lost my job I've been researching cyclones again with a view to making a living from selling them - no product yet though.
>
>There are quite a few improvements that people have made to improve the Wood cyclone. It was a pretty rough design. The good news is that even rough designs work reasonably well. However, if you'd
>like to build a better cyclone, here is my list of recommendations.
>
>Use heavier gage galvanized iron. I used 26 gage and that seems fine to me. My local steel companies sometimes stock 26 gage but often the lightest they have is 24 gage.
>
>Note: cyclones are described in terms of the diameter of the barrel. This dimension is called D. A 1D3D cyclone has a barrel that is as tall as it is wide and a cone that is 3 times the height of
>the barrel. a 2D2D cyclone has a barrel and a cone that are both twice the height of the diameter.
>
>The most efficient dust separating cyclones are 4D tall. Either a 1D3D or 2D2D design. The papers I've read consistently get slightly better but not statistically significant dust separation with a
>1D3D. Many people consider 1D3D the best design.
>
>So, if you have space, use a 1D3D cyclone. Bill Pentz claims that a 1D1.67D cyclone is a sweet spot for shorter cyclones.
>
>Use a rectangular inlet. The standard dimension for a 1D3D cyclone (h x w)is D x D/8. However, there are studies that show better performance with a D/4 x D/2 inlet. The D/4 x D/2 inlet is also
>less likely to clog than a narrower design. The dimensions also work out nicely if you use the vortex finder modification.
>
>Use a bigger vortex finder. Bill Pentz (see link below) recommends D/2.
>
>Use a shorter vortex finder. It needs to stick into the barrel down to at least the bottom of the inlet to prevent excessive short-circuiting (dust blowing directly from the inlet to the outlet
>without spinning around). If it's too long (say down to the bottom of the barrel or longer) the air can have trouble making a smooth change of direction up the vortex finder. There is a CFD
>(Computational Fluid Dynamic) model that shows a torodial eddy around the vortex finder just below the cylinder head. The eddy can carry dust straight down the side of the barrel and then straight up
>the vortex finder. I'd make the vorex finder extend an inch or two below the level of the inlet bottom.
>
>Use a neutral vane. IOW, extend the inlet into the barrel and end it on a radial plane that runs vertically through the barrel. This reduces the amount of energy required to run the cyclone. If
>you're really particular, you can test your cyclone and slide the inlet in until you get minimal pressure drop. Once you find the optimal location, lock it down.
>
>Use an air ramp. This is just a spiral ramp that starts at the top of the inlet and spirals down to meet the bottom on the inlet. This reduces the pressure drop of the cyclone.
>
>If you have space for a 1D3D with height left over, use a downcomer tube. This is just a straight pipe between the bottom of the cone and the dust bin. It's the same diameter as the dust outlet.
>The optimal length seems to be about D.
>
>An alternative to a downcomer tube is to put a cone in the dust bin. The paper I read used a 90 degree apex angle cone about 10% bigger than the dust outlet. Both the cone and the downcomer tube
>reduce the re-entrainment of dust from the dust bin. The additional pressure drop is about the same for both approaches.
>
>Another approach is to use a vane, about one inch tall near the bottom of the dust outlet. This vane is just fastened to the cone wall. IIRC, the paper I found that in used a length of 1D on a 3D
>cone. They reported that it improved collection efficiency. Unfortunately, I haven't been able to find that reference again. I suspect it works much as the downcomer tube does.
>
>The bad news is that the modifications to improve separation efficiency increase the pressure drop. The downcomer tube costs about 20% more pressure drop. Using the D/2 x D/4 inlet in conjunction
>with a D/3 dust outlet (about what Wood magazine specified) costs about 20%.
>
>That means that it is important to use the modifications that reduce pressure drop. In particular, use a neutral vane. Bill Pentz reports that a neutral vane reduces pressure drop by about 30%.
>
>On one of his spreadsheets, Bill Pentz estimates that using an air ramp saves about another 15% in pressure drop.
>
>You can also make the cyclone a little bigger; running a 1D3D with an inlet velocity of 2,600 fpm costs less pressure drop than the standard 3,4200 fpm but does little to collection efficiency, it may
>even help.
>
>To keep the air flow up, you'll also have to make sure that you have nice smooth transitions and long-radius curves in your ductwork. You'll probably want to run 6 inch pipe.
>
>And don't forget to get a big enough blower.
>
>Whew! Sorry for the long post.
>
>There is a wealth of information at Bill Pentz's web site:
>
>http://cnets.net/~eclectic/woodworking/cyclone/
>
>I posted some of my "lessons learned" after I built my first cyclone:
><http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=3b2d934f.21004476%40news.cncx.net&rnum=1>
>
>Bob S
-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----
At this point I just have cost targets. For my first product,
I want to be able to sell a cyclone without the blower for
something in the $300 to $400. That's still more of a kit
than a complete solution but it would allow someone to put
together a 2 HP dust collector for less than the comparable
PSI model.
I'll have a better idea of the cost after I get some quotes
for manufacturing them. I'll need to finish my drawings to
do that.
One thing that I have learned so far is that I can't fabricate
cyclones fast enough to make a living!
Bob S
On Sun, 02 Nov 2003 17:55:28 -0700, WD <[email protected]> wrote:
>On 02 Nov 2003 22:02:14 GMT, [email protected] (Bob
>Summers) wrote:
>
>What would be the estimate cost for a 2 HP cyclone?
>
>
>
>>On Fri, 31 Oct 2003 16:23:16 GMT, "Kevin" <[email protected]> wrote:
>>
>>>I am planning on building the cyclone from Dec 2001 issue of best-ever
>>>Workshops from Wood Magazine. It seems to me that I read somewhere that one
>>>of the recommended enhancements was to extend the inlet pipe several inches
>>>inside the cyclone cylinder to force the rotation of the airr current.
>>>Unfortunately, all magazine and internet searches for this enhancement have
>>>turned up 0 results.
>>>
>>>Does anyone have a list of recommended changes to this cyclone?
>>>
>>>Thanks,
>>>Kevin Meier
>>>
>>I built a cyclone based on the Wood version a few years back. Since I lost my job I've been researching cyclones again with a view to making a living from selling them - no product yet though.
>>
>>There are quite a few improvements that people have made to improve the Wood cyclone. It was a pretty rough design. The good news is that even rough designs work reasonably well. However, if you'd
>>like to build a better cyclone, here is my list of recommendations.
>>
>>Use heavier gage galvanized iron. I used 26 gage and that seems fine to me. My local steel companies sometimes stock 26 gage but often the lightest they have is 24 gage.
>>
>>Note: cyclones are described in terms of the diameter of the barrel. This dimension is called D. A 1D3D cyclone has a barrel that is as tall as it is wide and a cone that is 3 times the height of
>>the barrel. a 2D2D cyclone has a barrel and a cone that are both twice the height of the diameter.
>>
>>The most efficient dust separating cyclones are 4D tall. Either a 1D3D or 2D2D design. The papers I've read consistently get slightly better but not statistically significant dust separation with a
>>1D3D. Many people consider 1D3D the best design.
>>
>>So, if you have space, use a 1D3D cyclone. Bill Pentz claims that a 1D1.67D cyclone is a sweet spot for shorter cyclones.
>>
>>Use a rectangular inlet. The standard dimension for a 1D3D cyclone (h x w)is D x D/8. However, there are studies that show better performance with a D/4 x D/2 inlet. The D/4 x D/2 inlet is also
>>less likely to clog than a narrower design. The dimensions also work out nicely if you use the vortex finder modification.
>>
>>Use a bigger vortex finder. Bill Pentz (see link below) recommends D/2.
>>
>>Use a shorter vortex finder. It needs to stick into the barrel down to at least the bottom of the inlet to prevent excessive short-circuiting (dust blowing directly from the inlet to the outlet
>>without spinning around). If it's too long (say down to the bottom of the barrel or longer) the air can have trouble making a smooth change of direction up the vortex finder. There is a CFD
>>(Computational Fluid Dynamic) model that shows a torodial eddy around the vortex finder just below the cylinder head. The eddy can carry dust straight down the side of the barrel and then straight up
>>the vortex finder. I'd make the vorex finder extend an inch or two below the level of the inlet bottom.
>>
>>Use a neutral vane. IOW, extend the inlet into the barrel and end it on a radial plane that runs vertically through the barrel. This reduces the amount of energy required to run the cyclone. If
>>you're really particular, you can test your cyclone and slide the inlet in until you get minimal pressure drop. Once you find the optimal location, lock it down.
>>
>>Use an air ramp. This is just a spiral ramp that starts at the top of the inlet and spirals down to meet the bottom on the inlet. This reduces the pressure drop of the cyclone.
>>
>>If you have space for a 1D3D with height left over, use a downcomer tube. This is just a straight pipe between the bottom of the cone and the dust bin. It's the same diameter as the dust outlet.
>>The optimal length seems to be about D.
>>
>>An alternative to a downcomer tube is to put a cone in the dust bin. The paper I read used a 90 degree apex angle cone about 10% bigger than the dust outlet. Both the cone and the downcomer tube
>>reduce the re-entrainment of dust from the dust bin. The additional pressure drop is about the same for both approaches.
>>
>>Another approach is to use a vane, about one inch tall near the bottom of the dust outlet. This vane is just fastened to the cone wall. IIRC, the paper I found that in used a length of 1D on a 3D
>>cone. They reported that it improved collection efficiency. Unfortunately, I haven't been able to find that reference again. I suspect it works much as the downcomer tube does.
>>
>>The bad news is that the modifications to improve separation efficiency increase the pressure drop. The downcomer tube costs about 20% more pressure drop. Using the D/2 x D/4 inlet in conjunction
>>with a D/3 dust outlet (about what Wood magazine specified) costs about 20%.
>>
>>That means that it is important to use the modifications that reduce pressure drop. In particular, use a neutral vane. Bill Pentz reports that a neutral vane reduces pressure drop by about 30%.
>>
>>On one of his spreadsheets, Bill Pentz estimates that using an air ramp saves about another 15% in pressure drop.
>>
>>You can also make the cyclone a little bigger; running a 1D3D with an inlet velocity of 2,600 fpm costs less pressure drop than the standard 3,4200 fpm but does little to collection efficiency, it may
>>even help.
>>
>>To keep the air flow up, you'll also have to make sure that you have nice smooth transitions and long-radius curves in your ductwork. You'll probably want to run 6 inch pipe.
>>
>>And don't forget to get a big enough blower.
>>
>>Whew! Sorry for the long post.
>>
>>There is a wealth of information at Bill Pentz's web site:
>>
>>http://cnets.net/~eclectic/woodworking/cyclone/
>>
>>I posted some of my "lessons learned" after I built my first cyclone:
>><http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=3b2d934f.21004476%40news.cncx.net&rnum=1>
>>
>>Bob S
>
>
>
>-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
>http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
>-----== Over 100,000 Newsgroups - 19 Different Servers! =-----
On Bill Pentz's website (the link was given above), he gives the email
address for a guy named Clarke Echols. He's selling snap together
kits using Bill's design. Cost is $150 + $35 shipping to the
Continental US. He's also selling steel blowers for the same price.
You would still have to buy a motor ($79 from the guy on Ebay Bill
used in his airfoil design), an impeller (I'm going with an airfoil
for $135 I think), and the filter. Just another option.
Cheers,
cc
In article <U%vob.89691$EO3.55445@clgrps13>,
"Kevin" <[email protected]> wrote:
> I am planning on building the cyclone from Dec 2001 issue of best-ever
> Workshops from Wood Magazine.
I'd recommend a much stronger material, besides, you may want to re-read
the magazine some time.
;-)
-JR
aka
Wiseass
Never mind, I just found what I was looking for on
rickswoodshopcreations.com
Kevin
"Kevin" <[email protected]> wrote in message
news:U%vob.89691$EO3.55445@clgrps13...
> I am planning on building the cyclone from Dec 2001 issue of best-ever
> Workshops from Wood Magazine. It seems to me that I read somewhere that
one
> of the recommended enhancements was to extend the inlet pipe several
inches
> inside the cyclone cylinder to force the rotation of the airr current.
> Unfortunately, all magazine and internet searches for this enhancement
have
> turned up 0 results.
>
> Does anyone have a list of recommended changes to this cyclone?
>
> Thanks,
> Kevin Meier
>
>
The absolute master of home made cyclones is Wayne Davey. His
messages and the pics and instructions for the cyclones he makes are
free and they are easy to build and work.
Wayne posts on Australia's woodwork Forums
http://www.woodworkforums.ubeaut.com.au/showthread.php?s=&threadid=3749&highlight=cyclone
Glenn
www.metalbashatorium.com
"Kevin" <[email protected]> wrote in message news:<U%vob.89691$EO3.55445@clgrps13>...
> I am planning on building the cyclone from Dec 2001 issue of best-ever
> Workshops from Wood Magazine. It seems to me that I read somewhere that one
> of the recommended enhancements was to extend the inlet pipe several inches
> inside the cyclone cylinder to force the rotation of the airr current.
> Unfortunately, all magazine and internet searches for this enhancement have
> turned up 0 results.
>
> Does anyone have a list of recommended changes to this cyclone?
>
> Thanks,
> Kevin Meier
Kevin
Have a look at Bill Pentz website
http://cnets.net/~eclectic/woodworking/cyclone/Index.html
There is quite a lot of useful info there as well as free plans using
an optimised design.
Regards George SA
Wow, he has quite the web site discussing cyclones. Thanks for the
reference to it Glenn.
--
Larry C in Auburn, WA
"Glenn Cramond" <[email protected]> wrote in message
news:[email protected]...
> The absolute master of home made cyclones is Wayne Davey. His
> messages and the pics and instructions for the cyclones he makes are
> free and they are easy to build and work.
>
> Wayne posts on Australia's woodwork Forums
>
>
http://www.woodworkforums.ubeaut.com.au/showthread.php?s=&threadid=3749&highlight=cyclone
>
> Glenn
> www.metalbashatorium.com