A little challenge

[shipwright]

I just looked up the stats on my HFDC here http://www.harborfreight.com/2-hp-indus ... 97869.html and as you can see at 1550 cfm it has almost 5 times the volume that the DC330 (330 cfm) has. So thats likely the reason for my good fortune with the chips because as we all know with dust collection its all about volume.

Paul M

[Ed in Tampa]

I relate to all that you say. I believe we have exactly the same configurations. A couple to pictures taken from the right position will reveal that.

I have scratched a mark in my headstock and lower saw guard to aid in alignment so that when the table is lowered it contacts the movable gate on the lower saw guard evenly.

The area where I located the dust deflector is very close to the saw blade. Without going out to check, I would say there is less than a 1/4" clearance. Maybe more like an 1/8".

Dusty
Perhaps I don't understand. I thought you and cabinetmaker found the problem to be the space on the front of the lower blade shield between the shield and the table.
Is that right?

If it is then I think the reason I don't have a problem with dust is two fold. Usually my lower blade guard is tilted so the front of it contacts the table first. Then I also use my saw in with more of the blade exposed so the table is closer to the lower guard.

Now if you put the two together my table and saw guard almost touch where you put the addon shield. That is probably why I hardly get any dust and others do.

If I install the lower blade guard level (which never happens no matter how hard I try) and keep the table height adjusted so a small portion of the blade is exposed then I would have gap you fashioned the shield to close.

[mbcabinetmaker]

Dusty
Perhaps I don't understand. I thought you and cabinetmaker found the problem to be the space on the front of the lower blade shield between the shield and the table.
Is that right?

If it is then I think the reason I don't have a problem with dust is two fold. Usually my lower blade guard is tilted so the front of it contacts the table first. Then I also use my saw in with more of the blade exposed so the table is closer to the lower guard.

Now if you put the two together my table and saw guard almost touch where you put the addon shield. That is probably why I hardly get any dust and others do.

If I install the lower blade guard level (which never happens no matter how hard I try) and keep the table height adjusted so a small portion of the blade is exposed then I would have gap you fashioned the shield to close.

This is all making a lot more since now that I have read this post. I use my 520 almost exclusively to cut either 1/4 x 1/4 inch dado's or 3/4 wide x 1/8 deep dado's so I have always had this problem. I can't remember the last time that I had a 10 inch blade on but it would have been for a project out in the field with out a dust collector. I had never really looked at the space in front between the blade guard and table. The little deflector that I made works great at redirecting the chips being produced basically on top of the dado blades and I am sure dustys device does as well. I agree with dusty that the challenge has been met and thanks to all for the help, my 520 is still my favorite tool in the shop.

[dusty]

Dusty
Perhaps I don't understand. I thought you and cabinetmaker found the problem to be the space on the front of the lower blade shield between the shield and the table.
Is that right?

If it is then I think the reason I don't have a problem with dust is two fold. Usually my lower blade guard is tilted so the front of it contacts the table first. Then I also use my saw in with more of the blade exposed so the table is closer to the lower guard.

Now if you put the two together my table and saw guard almost touch where you put the addon shield. That is probably why I hardly get any dust and others do.

If I install the lower blade guard level (which never happens no matter how hard I try) and keep the table height adjusted so a small portion of the blade is exposed then I would have gap you fashioned the shield to close.

Yes, I did misunderstand what you were saying and I can close down on the size of the gap by tilting the lower saw guard so that the infeed edge is higher than the outfeed edge.

There are many variables in this set up and we have touched on only a few of them. What this means, I think, is that if you are not satisfied with the level of dust collection that you experience you may want to play around with this arrangement. However, if you are satisfied - leave it alone.

I am going to modify my guard modification to be more like Mark's. I think the combination of our two approaches will yield very good results and will only limit the setup variables slightly. (With the guard modified the lower saw guard cannot be closed down tightly on the blade)

I need to slip in another comment here: The other changes that I have made are really Ed Reibles' previous contribution to this issue.

[dusty]

I have been working on this problem for a while but had slacked off some. Mark reignited the challenge and I have done a bit more toward an improved dust collection method.

Why dust saw dust escape. Take a look at just a couple images and you will see. These photos are were taken with the Mark V ready to make saw dust.

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[dusty]

To reduce the amount of escaping dust, I cut and installed a reflector that I inserted into the lower saw guard. The vast majority of the saw dust escapes at the infeed edge of the lower saw guard. You can see that area in one of the previous four pictures. These shots were all taken with the insert removed, looking down through the insert opening. Notice how much of the floor and the Mark V under carriage can be seen (through the dust collector).

I have installed a dust deflector that keep some (most all) of the saw dust from escaping through this area. The saw dust is simply held within the lower saw guard so the the DC air stream can collect it.

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The final configuration.

The first two views in this thread simply show where the deflector is mounted. I changed its size and shape on the run.

One other thing that I plan to do is revise the saw insert to occupy some of that space below the insert. This will lower the under table surface so that there is less space between the lower saw guard and the table. The more that dust cannot escape the more dust will be collected by the DC.

[dusty]

If anyone is interested, here are the dimensions of dust deflector that I now have installed. It is cut from a piece of plastic like material that is very flexible while at the same time remains flat if no pressure is applied to it.

[ATTACH]9469[/ATTACH]

[BigSky]

Do you have a before and after that shows how effective this is.

Does this deflector attach to anything or is it just wedged in place.

Does it allow you to change the depth of cut.

[tryinhard]

Remember that making any of these additional mounts permanent will affect the use of the lower guard for sanding disk operation.

For the flat disk, you won't be able to use the dust collector since the table cannot be brought down to the center of the disk.

For the conical sander, you might actually get better collection since a front deflector in the saw guard will intersect the dust flying off the sanding disk.

[dusty]

Remember that making any of these additional mounts permanent will affect the use of the lower guard for sanding disk operation.

For the flat disk, you won't be able to use the dust collector since the table cannot be brought down to the center of the disk.

For the conical sander, you might actually get better collection since a front deflector in the saw guard will intersect the dust flying off the sanding disk.

I don't do well visualizing these things] Making permanent modifications to the Mark V can and often does impose restrictions on other functions. It is not obvious, on the surface, just how complex the design if the Mark V is until you start changing it. Everything is interdependent and until you have operated it in all of its various modes you do not know for sure.[/color]