Air assist head for K40 machine - LSR-LH1820B

[RogerC]

I have a K40 on order, my first laser, and one thing everyone seems to agree on (other than the horribleness of the OEM control boards) is that air assist is pretty much a necessity for certain types of work, and very helpful for most others.

With that in mind I ordered one of your air assist heads, but was slightly concerned by one of the reviews which suggests that the laser's focal point will be raised by about 8mm. Is this correct and if so, is this going to be something I have to correct for or will the focus be "good enough" without further adjustment? Does anyone have any experience with this head?

Thanks,

~R~

[Tech_Marco]

Yes it's true. You may want to remove the the cramping apparatus (installed on the table) and add a honeycomb. That should give you a pretty good readjustment. Or, you can add a washer(cut form a 3mmn epoxy glass) inside of the laser head to raise the lens up by 3mm to make it even better.

Marco

[RogerC]

Thanks for the info. Good tips, especially about the washer. I'd been thinking about ways to modify the machine, but hadn't thought of that one.

~R~

[Seeker]

Hi all!

I have just started reading here after buying a couple of parts then discovering this forum, and I feel smarter already! Well, sort of.

One of the things I bought was this air-assist head. Looks great, but I had a few questions... or at least one question and a confirmation that I understand how/where to put the lens.

I am guessing I remove the small (M3?) set screw and drop the lens in so it sits just above the air inlet. Correct? I am worried when I tighten up the set screw it might land on the lens and break it. A 'test mount' looks good, but it is very close.

And the question... how strong of an air flow do I need, and will a stronger one help with cutting hard to cut material. I read here someone said any small pump, even an aquarium pump would do. I was thinking something stronger that would not only keep smoke away from the lens, but also blow down through the nozzle and clear the smoke out of the cut too, and put out any fires . My original thought was a 50-60 psi airbrush pump. But if it would not do any more than a small aquarium pump, the added cost savings and lower noise levels would be a benefit. At least for my wife.

Thanks in advance for your help! I plan on spending a lot of time here.

[waltfl]

hi seeker
a airbrush pump would be what you need.
as in regards to the air assist cone I don't know what kind you got but the lens usually goes in the upper part of the laser head and the cone on the lower end of it.
greetings
waltfl

Hi all!

I have just started reading here after buying a couple of parts then discovering this forum, and I feel smarter already! Well, sort of.

One of the things I bought was this air-assist head. Looks great, but I had a few questions... or at least one question and a confirmation that I understand how/where to put the lens.

I am guessing I remove the small (M3?) set screw and drop the lens in so it sits just above the air inlet. Correct? I am worried when I tighten up the set screw it might land on the lens and break it. A 'test mount' looks good, but it is very close.

And the question... how strong of an air flow do I need, and will a stronger one help with cutting hard to cut material. I read here someone said any small pump, even an aquarium pump would do. I was thinking something stronger that would not only keep smoke away from the lens, but also blow down through the nozzle and clear the smoke out of the cut too, and put out any fires . My original thought was a 50-60 psi airbrush pump. But if it would not do any more than a small aquarium pump, the added cost savings and lower noise levels would be a benefit. At least for my wife.

Thanks in advance for your help! I plan on spending a lot of time here.

[Seeker]

hi seeker
a airbrush pump would be what you need.
as in regards to the air assist cone I don't know what kind you got but the lens usually goes in the upper part of the laser head and the cone on the lower end of it.
greetings
waltfl

Hi Waltfl, thanks for the reply!

I thought the airbrush pump was that way to go. As far as the air-assist model, it is the LSR-LH1820B mentioned in the title of the thread. That is why I posted in this thread rather than start a new one. It seemed logical to keep all of the info on one product in the same place. I realize you had no way to know that and I should have mentioned it in the original post.

The version I got was the newer one with the air-input barb rather than the large fitting. The only place I can see for the lens to fit was the way I described it, but I wanted to make sure I wasn't missing something obvious.

Hopefully I can get to Harbor Freight this weekend and pick up a pump. This my first real mod to the K40. Once this is done I'll have to decide what to do next!

[Tech_Marco]

The M3 screw is used to hold the laser tip from drop off. Your lens should be installed inside a ring above the M3 screw. It is detachable and some folks may confuse that it was a single unit but it is not. The laser head is combined with 3 parts

Marco

[Seeker]

The M3 screw is used to hold the laser tip from drop off. Your lens should be installed inside a ring above the M3 screw. It is detachable and some folks may confuse that it was a single unit but it is not. The laser head is combined with 3 parts

Marco

Ahhhh... I see. I knew it was three parts, but I thought the middle part was just to hold the mirror mount (top part) on to the bracket the whole thing rides on. Like the middle part on the original head. Now I see, it is the lens mount.

Hmmmm... I just noticed... the threads are the same as on the original head. So if I keep the middle part of the original head and use it to attach the new mirror mount to the bracket (or just use the original mirror mount and it the way they are) I can use the new lens mount part and air nozzle tip. This keeps the lens at the original location and not 8mm higher like some have complained about. I got the impression from that statement (the 8mm thing) that only the three new parts were to be used. But using one of the old parts makes everything fit perfect.

Does that make sense, or should I take pictures?

Edit to add: Marco, I just looked at one of your older posts from last year, and I see this is exactly how you did it. Sorry, I hadn't read that far back until just now.

[Tech_Marco]

No problem. Even though myself got lost and couldn't recall where I put those post. I was trying to find the pictures I took and posted it here but I couldn't find it on my PC. Was thinking to re-take images when I got back to office. Since you got it fix, now I can take a break, enjoy my coffee and cookies

Marco