DC Arm for 21829

[Bill in Buena Park]

Still playing with ways to improve my DC using the new Delta, I decided to try constructing some above-table DC for my 21829 through a branch line riser to my blade guard.

Like my bandsaw DC experiment, I used 3" black PVC drain pipe, the OD of which couples fairly nicely to the 4in DC hose, but used a fitting that had a 2in Y branch on it. To the branch I added a 2" arm/riser assembly, to the end of which I Gorilla-taped a short piece of 2.5" shopvac hose. The shopvac hose goes over and down to the blade guard, which is my stock guard modified by sawing out a channel at the top and attaching a modified vacuum attachment.

The whole contraption is also fitted to the 2.5in DC port on the back of the saw using a 3in-2in reducer and a rubber coupler, and is quickly attachable and removable from the saw. I created a support hanger from scrap ply and some L-brackets, which is T-nutted to the back rail, which easily supports the weight of the whole deal.

Results - working to my satisfaction, very little dust getting past the blade guard even with my ZCTP in place. Don't think I would have tried this split-line approach with my shopvac.

Thanks for looking.

[LCHIEN]

That's a problem I have been mentally wrestling with for ages. Still spewing dust off the top of my BT.
Your solution looks good except...
what do you do when you make a bevel cut?

[pelligrini]

That's pretty cool.

I just have a 4" clear flex hanging from several bungee cords going to my shark guard, and another 4" black flex connecting at a manifold I built for my jet 650.

[Bill in Buena Park]

Loring, Erik - thanks for comments.

...what do you do when you make a bevel cut?

I haven't tried this for a bevel cut yet, but recalling my last bevel cut... With our right-tilt arbors, this will still work since the hose is flexible and I left enough to span... and my 21829 guard is raised off the table a little (by design) on the right side, I believe to accommodate the right-tilt bevel. So there will still be airflow, just not sure how effective, especially at 45 dg. I'll try that this weekend and report back.

[kevincan]

That's a cool looking set up. I seem to get a lot of dust from the top of the saw especially with a ZCTP in place. How far away from the blade is it - can it be removed if you are cutting longer items on the SMT?

[Bill in Buena Park]

...How far away from the blade is it - can it be removed if you are cutting longer items on the SMT?

Kevin,
The riser sits a foot or better behind the back teeth of the blade, but more importantly, about 21" behind the front teeth. This allows a crosscut depth greater than I can get on the SMT.

The riser also sits about 22" to the left of the blade, meaning that I'd need to crosscut something where the remnant to the left of the blade would be larger that 22" wide and 21" deep before I bump the riser.

For crosscutting (or ripping) items that large, the riser arm/hose assembly can be loosened and removed from the adapter fitting I've mounted to the saw's dust port with a twist-lift and a tug (currently a friction fit.) Also installs that fast. Accordingly, the support bracket is needed to defeat gravity and hold things in place.

[docrowan]

Loring, Erik - thanks for comments.



I haven't tried this for a bevel cut yet, but recalling my last bevel cut... With our right-tilt arbors, this will still work since the hose is flexible and I left enough to span... and my 21829 guard is raised off the table a little (by design) on the right side, I believe to accommodate the right-tilt bevel. So there will still be airflow, just not sure how effective, especially at 45 dg. I'll try that this weekend and report back.

I think Loring's concern is when you tilt it to 45 then you lose the support of your plywood brace. Since you are right tilting the brace won't interfere with the travel, but it won't tilt with it, so no support.

[pelligrini]

The low port could swivel, might still be a little messed up in alignment with the bracket though. I'd probably just disconnect the low port when doing tilted cuts. (which isn't all that often for me)

[Bill in Buena Park]

I think Loring's concern is when you tilt it to 45 then you lose the support of your plywood brace. Since you are right tilting the brace won't interfere with the travel, but it won't tilt with it, so no support.

Ah, yes - now I understand, and think a minor modification to the plywood brace can accommodate.

As Erik states, the low port will swivel, allowing the arm to stay level - so my original thought was to pivot the brace upward to the left from its pivot point on the rail, but that would place the pressure on the left edge of the brace, not into the hook part - probably strong enough, but maybe not stable.

I'll reconfig the brace so the bottom part also pivots so the hook can be at the bottom, even when the longer portion is swung out to the left.

Thanks for the improvement suggestion. I'll post a pic of the mod to the support when done.

[Bill in Buena Park]

Support brace Redux

Ok - I think I have this brace issue corrected.

I took the straight brace, cut it in half, and added an "articulating" pivot piece, which allows me to manipulate the brace into a more desirable position for the DC arm anywhere from 0 to 45 dg. The segment that attaches to the rear rail has been cut down to allow for better movement, and the wingnuts (which I will most likely replace with star knobs) do a decent job of holding things firmly together.

Ran the DC while at 45 dg, works very well - but not sure if this is because there is now better under-table pull since I had to change from the ZCTP to the stock TP, which improves airflow.

Discovered that lifing the arm to accommodate the 45dg cut reduces my distance from blade to arm to 17in (i.e., max off-cut piece left of the blade.

Other improvement insights are welcome! Thanks for looking.