Veteran K40 owners: Do you find that the stock vent manifold that extends into the bed is valuable, or have you removed/trimmed it back without noticing a decrease in ventilation?
I ask because, during testing I’ve found I have an additional ~30mm of play on both axes and I’d like to be able to use, and the vent manifold is in the way.
Thoughts?
I cut mine maybe an inch. That’s the material my grinder can cut without hitting the wall. The vacuum is still the same with the exhaust
I removed mine
Took mine out. The exhaust works well without it in the way. It’s probably the first mod most people do to these.
Given how much room it takes up compared to the size of the chassis hole, I wouldn’t be surprised if exhaust actually improved somewhat by removing it entirely. Okay then, thanks for the feedback. I’ll yank mine entirely and give it a try.
I cut mine only hoping to get a bigger cutting area. Removing it did not give me more. That’s why I only took what I need. Beyond that, it dies not give more area
my laser head is capable of traveling to about 230mmx330mm, and the manifold does occupy some of that extra space. shrug I guess we’ll see what happens when I actually try to use that space for a job. 
@Bob_Buechler not a “veteran” but I removed mine once I knew everything was working ok. Removed it and installed a bigger fan by cutting a round hole in the extraction point. In my view it’s much better and keeps the chamber fume free. that’s the main reason I did it rather than more bed room.
Anyway you want to do it when you go for the honeycomb bed mod ;-))
I can’t find a decent adjustable bed mod that doesn’t cost an arm and a leg…
@Bob_Buechler
best idea is that one
https://plus.google.com/+ScorchWorks/posts/UkrvPtra7UK
I totally removed mine. I get 330 x 230mm on my K40 bed. Removed what I believe was a covering angle bracket over the front stepper motor to gain maybe +10mm to bring it to 230 on the Y.
I also attached some plywood onto the default exhaust fan at the top half (which didn’t suck through the air vent hole anyway) because it was preventing a good seal on the K40 vent area.
@Bob_Buechler I picked up a $15. Lab jack from ebay, attached it with double sided tape to enclosure bottom and sit honeycomb bed on the jack. Works good enough that I’m considering extending the jack knob out the front for easier adjustment.
I have no idea how the stock one worked as it came out within 5 minutes of owning it. I can say that with the squirrel cage blower I have on it I don’t need the duct… just printed this guy today as an additional mod to the vent system.
I cut my manifold back flush with the edge of the XY table frame. I found that the airflow taking fume away from the part being cut was much better than fully removing it. I used a decent in-line duct fan in my outlet tube and I am very satisfied with the air flow. Here is my duct fan which I put closest to the exit of the house so as to minimize the portion of the duct which was exposed to positive pressure. I bought the 6" dia version.
I also used this dust hood adaptor to connect to some duct work. It fits perfectly on the back of the K40. I immediately used standard duct work to convert this to 6 in dia duct work. You can see the fumes flying away from the work. Nice!
I trimmed mine back so it did not cross the rail. I took it out all together once and smoke was all over, but that was also with the stock fan. I have upgraded that to a real blower and never been happier.
I left it in so the air flow is going across the top of the piece, rather than underneath where it isn’t doing any good. But if you’ve got a big enough fan it probably doesn’t matter.
My manifold is screwed in and not spot welded like the older ones, but it doesn’t seem easy to remove. They cut part of the back gantry rail to make room for it, and now that the tube compartment is in place, the manifold looks kinda wedged between what’s left of the rail and the bottom of the tube compartment. And since the manifold is larger than the rear exhaust hole, I can’t just pull it out from the back.
Any tips on how to remove it without taking apart the gantry?
@Bob_Buechler Mine seemed the same as what you describe. I pulled it out by removing the gantry. The gantry removal was very simple (just 4 bolts if I recall correct).
@Yuusuf_Sallahuddin_Y hmm. Did all four rails have to come out, or just the back rail?
