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Lloyd
01-27-2008, 01:12 PM
I have read several posts about adding an additional air source to blow the dust and chips away from the bits while the machine is running. I was wondering what would happen if the muffler was removed and a flexiable hose attached and routed into the z truck and attached so it would always be blowing the chips away. If a downdraft table was also used wouldn't this arrangement keep the machine cleaner or would it cause a problem that I am overlooking.
I have not tried this, just wanting to get some opinions if this is possible?

Jeff_Birt
01-27-2008, 01:40 PM
I would not recommend routing the exhaust back into the machine. The exhaust is hot air laden with fine dust particles. If you route it back into the machine you will be risking overheating the cut motor by greatly restricting its cooling air flow (due to the small tubing required) and recirculating the same (hot) air.

It's best to use an external air source.

Ken Massingale
01-27-2008, 03:32 PM
I would not recommend routing the exhaust back into the machine. The exhaust is hot air laden with fine dust particles. If you route it back into the machine you will be risking overheating the cut motor by greatly restricting its cooling air flow (due to the small tubing required) and recirculating the same (hot) air.

It's best to use an external air source.
What's the reason for not attaching a vac to the muffler port to evacuate the chips and hot air while the machine is running?

Jeff_Birt
01-27-2008, 04:50 PM
What's the reason for not attaching a vac to the muffler port to evacuate the chips and hot air while the machine is running?


Huh? There was no mention of a vac in this thread at all. The OP was talking about routing the CW exhaust back into the machine.

Ken Massingale
01-27-2008, 05:39 PM
Huh? There was no mention of a vac in this thread at all. The OP was talking about routing the CW exhaust back into the machine.
I know what the OP was asking, Jeff.
I'm not allowed to ask an associated question that is related to the OP?

TIMCOSBY
01-27-2008, 06:04 PM
port with a vacuum would not pick anything more up than it allready does and that aint much. some of the exhaust is rerouted to blow across the board.

bjbethke
01-27-2008, 06:52 PM
I think it would build up more fine dust into the machine to route the exhaust back into the machine. I believe that would mess up your safety switches. A lot of dust comes out of that port. The sock on my Vacuum Bag Assembly has a hole in it and carving walnut my walls are covered with walnut dust. I plan on using a 2 ½ inch hose on the Vacuum Bag Assembly and route it through my vacuum system and blow all that fine dust out of my building. I don’t use a bag to collect the chips; they help cover up the Arkansas rocks outside.

With my down draft system I do not have any chips around my carving bit. The exhaust blower, the up spiral bit and the speed of the Z truck blow the dust from the carving area, and the down draft removes the dust (see Photo). More dust is left on the carving with the 3/8th straight bit, but not where the bit carves. It is easy to clear these chips with an air hose when the carving comes out of the machine in long carvings. Small carvings do not collect chips.

The only problem with up spiral bit is they leave all those fuzzes, but a down spiral would pack the chips into your carvings.

I think this is a great machine. It works well for me. It’s easy to operate, once you understand what it is trying to do.

twinpeaksenterprises, LLC
01-27-2008, 10:05 PM
Feel free to do what you want in the quest for better chip and dust control but i believe the bottom line is as so many others have said before me, a downdraft system is the solution to so many problems. Its the only option that makes sense in my opinion. I wouldnt try to do any modification to the muffler whatsoever except clean it regularly. But i highly reccomend a homemade downdraft system. Its mind boggling why that port on the bottom of the machine is not mentioned in the manual. Here is a few pictures of our simple homemade down draft system which was made by modifying a previous workbench. Made a small chamber and inserted a 90 degree dust collection elbow. Then measured and made a cut out of the port on the bottom of the machine. Layed out adhesive foam to make an air tight seal and hooked into our 1200 cfm dust collector.

pkunk
01-27-2008, 10:20 PM
Heheh, when you have a big enough DC, you don't need to bolt the Carvewright down!

badger
01-28-2008, 02:12 AM
Heheh, when you have a big enough DC, you don't need to bolt the Carvewright down!



lol, not everyone here knows how to set up a nuclear rig like yours though ;)

Ive not had any problems once about every hour blowing some of it away during a carve and after every carve blowing the rest of it out of the machine.

Lloyd
01-28-2008, 08:13 AM
Thanks for all the imput. I do have a down draft table under the machine, but a lot of dust and chips still land in areas that will not be removed. I thought maybe more air flow would cause thwe chips to be picked up. I guess I will continue to stop every 15-20 minutes and use the shop vac. That has worked so far.

twinpeaksenterprises, LLC
01-28-2008, 08:24 AM
Just out of curiousity how many cfg is your dust collector. Its inevitable were going to have to deal with some chips theres no way around it. Its the fine dust that worries me not only for my own health but for the health of the machine and the dust getting into switches and the motor and other electrical areas where dust isnt supposed to be.. Happy Carving!

twehr
01-28-2008, 08:46 AM
Whether we are talking about the dust collector or the project, size matters.

The larger the dust collector capacity (air movement), the better it will remove both dust and small chips through the downdraft port in the bottom of the machine.

At the same time, the larger the project (height), the smaller the amount of dust and chips you can get to the downdraft port. I use a 14.5" sled for nearly all of my projects. That means there is almost no access to the downdraft port and all the chips still build up on the project and sled.

Sounds like a decision needs to be made: Is it better (faster, easier, cleaner, better quality, cheaper.....) to eliminate the sled and get better dust collection, or use the sled and 7" additional wood and work harder at cleaning during and after projects? For the most part, I have chosen to spend the time cleaning. I have a process down that, as long a followed, virtually eliminates all the sensor errors and stuck bits. But still, if there were a way.....

In another post, I have seen the attempt at putting the 4" collector port on the back side (opposite the control panel). I recall the experimenter thought it did not do much good. My question, in case anyone has tried this, is: What would happen if you used that same approach AND used compressed that is pointed to direct the air (and chips and dust) toward that collector port?

One idea I plan to try (as soon as I am out of warranty) is to replace (or fit) the clear cover with both an air source (for suspending the chips and dust in air) and a DC port for extraction.

(BTW - if you are concerned about blocking your view of what is going on inside, I have a solution for that. I already set up a cheap video camera with microphone ($39) that goes to a 7" monitor. It allows me to watch and listen from my attached office. If I suspect a problem, the machine is only 8 feet away - closer that I usually am when I stay in the shop and work on other things.)

Just some thoughts. Whoever figures out a system that works, regardless of the size of the project, will surely be a hero to the rest of us.

Lloyd
01-28-2008, 08:49 AM
I don't know what the cfm of the collector is. It was a cheap one that I bought at a tool sale. It works good on my router table, bandsaw and scrool saw it could be it's just not big enouhg to handle a downdraft table. I modified it so that it exhasts outside to try to keep the dust down in the shop. My shop is in the basement so dust control is very important.

Semper Fi
01-28-2008, 08:59 AM
As a matter of fact, I did hook up my exhaust port to a hose and reducer that directed the air into the cutting area. I have a downdraft table built for my machine and I too figured if I could get the chips and dust in suspension, the dust collector would suck them out and away. It did work to a certain degree, but not what I would call satisfactory. I went back to blowing out the areas with my air compressor while the machine was carving. I also had a concern with the heat on the cut motor because I had to reduce the opening of the hose to get enough velocity to move the chips and dust. It would be nice to come up with a way to keep the machine clean while it was cutting and carving. The Holy Grail alludes for now, but I'm gonna keep trying! :)

Ernie

pkunk
01-28-2008, 10:23 AM
Most shop vacs under $250 are not designed to run for long periods. They will burn up! I have several that I use on my random orbit sanders that will but they have 2 stage motors and cost around $350 each. Less expensive shop vacs also are very prone to excessive static charges. You all would be better off with an inexpensive DC & upgrade the Bags/filter to a better micron rating. You don't need the 1800 cfm that I have. I often have 2-3 machines running in the shop at the same time that are needing major chip removal such as a table saw, jointer, & shaper. I can fill that 55 gal container 3-4 times in a good day.:p