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Re: Constructing Janus, by Dirk

PostPosted: Mon Sep 05, 2011 2:33 am
by bdring
I don't like how loud mine is and the strong pulsing of the air. I put a ball valve in line and usually run it with the valve half way shut. It reduces the noise and the pulsing of the air. I think it acts as a pneumatic RC filter. R = ball valve and C = the volume of air before the valve. It might work even better to increase the volume in front of the valve. Maybe a small bit of PVC pipe. I just have about 6 feet of 3/16 tubing.

Re: Constructing Janus, by Dirk

PostPosted: Mon Sep 05, 2011 6:48 pm
by dirktheeng
I've been thinking about getting this pump:

quietpump.jpg
quiet air pump


This pump does 400LPH, which is 6.6 LPM. It has 2 outputs and has 2 diaphragm pumps in it (I think they are in opposite phases which will help reduce pulsing). I was also thinking about putting a down tube from the nozzle to very close to the focal length so I maximize the force of the air. It also has flow control valves in it and is rated at 30 db from about 3 feet. it also has 3/16 outlets which match our air tube.

Janus lives.... first cuts

PostPosted: Mon Sep 05, 2011 8:55 pm
by dirktheeng
Well, today is another exciting day in my life. I got first cuts with the laser... hard to believe but true. I got everything aligned nicely now and made a couple cuts... really need to get the ventalation system hooked up as it made the place smell like burnt wood and gave me a soar throat a bit, but here's the video to prove that it works. I didn't even hurt myself at all either ! :D


Re: Janus lives.... first cuts

PostPosted: Tue Sep 06, 2011 12:19 am
by onlyjus
dirktheeng wrote:Well, today is another exciting day in my life. I got first cuts with the laser... hard to believe but true. I got everything aligned nicely now and made a couple cuts... really need to get the ventalation system hooked up as it made the place smell like burnt wood and gave me a soar throat a bit, but here's the video to prove that it works. I didn't even hurt myself at all either ! :D


Wooooo! That looks awesome! You'll have to invite me over to check it out!

I assume you used HeeksCNC to generate the GCODE?

Re: Constructing Janus, by Dirk

PostPosted: Tue Sep 06, 2011 1:31 am
by metalman
Congratulations Dirk! Lookin' good. Count me in too for the show and tell.

Jay

Re: Constructing Janus, by Dirk

PostPosted: Tue Sep 06, 2011 2:08 am
by BenJackson
Get that air suction system going. I also cut some scrap plywood right off the bat with insufficient venting and the glue has given the interior of my laser a distinctly skunky smell. I also had to clean the inside of the window to remove a fog of smoke.

Re: Constructing Janus, by Dirk

PostPosted: Tue Sep 06, 2011 11:30 pm
by dirktheeng
BenJackson wrote:Get that air suction system going. I also cut some scrap plywood right off the bat with insufficient venting and the glue has given the interior of my laser a distinctly skunky smell. I also had to clean the inside of the window to remove a fog of smoke.


Fortunately, this didn't happen with mine but I don't want to cut anything again until I get the ventilation in place cuz it stinks up the house and my wife would not like that. I can handle the smell, but life's miserable when "momma" aint happy. Happy wife, happy life! Just kidding... kindof. I don't want to do it because I know it bothers her and I love her so I can wait.

Generating spare parts and a cheap easy lens center solution

PostPosted: Wed Sep 07, 2011 12:10 am
by dirktheeng
All,

I found a good way to get the lens centered and unfortunately I scratched the lens good when I did it. However, I also divised a good way to keep from scratching anything while doing it.

Here's the end result:

DSCN4172.JPG
End Result


You can see the nice scratch I put in the lense (it runs from the lower left to the middle-upper-right with a nice hook at the top). I was originally trying to work with the lense without touching it and my tweezers slipped and put a nice scratch in it. Now I recommend just holding the lens in place with your thumb while getting the springs in place and cleaning it after it is all set up. Use a q-tip and some acetone. You can also see the circular scratches in the lens from when I first installed it... the circular scratches are off center becuase I didn't have the lens centered at first

The springs are 1/4" tygon tubing cut really thin and then cut into quarters.

I found the best way to cut the tubing is to press it on a table and use a very sharp knife. Make a cut to square up the end and discard that. Pressing the tubing down helps keep everyting square as the knife goes through. You can really cut this stuff thin this way. The more uniform the cut thickness, the better.

DSCN4163.JPG
cutting a thin section of tubing


Then just cut the sectioned tubing it into quarters.

The first 2 tubing springs go in really easy. Make sure the outer radius touches the lens.

DSCN4169.JPG
2 springs in place


Then hold the assembly with 2 fingers and pull the lens down with your thumb and be sure to cover the whole thing (make sure your hands are as clean as possible to avoid scratches).

DSCN4170.JPG
Pulling the lens down


Then you have to work the last spring in place. I used an xacto knife to get it in there. Keeping the lens covered with your thumb when you work with it ensures that you don't scratch the lens (this is what i should have done). Then you can position the springs evenly.

The nice thing is that you can visually center the lens by pushing on the edges and the tygon will keep the lens exactly where you moved the lens without springing it around... it's "grippy" enough to do this and not a really strong spring so it works well.

Once the springs are moved to the right position and the lens is centered, clean it with acetone to remove finger prints.

This works really well. I will be doing this agian when I get a new lens. I'll keep this one for a backup.

Re: Generating spare parts and a cheap easy lens center solu

PostPosted: Wed Sep 07, 2011 12:47 am
by twehr
dirktheeng wrote:Then you have to work the last spring in place. I used an xacto knife to get it in there. Keeping the lens covered with your thumb when you work with it ensures that you don't scratch the lens (this is what i should have done).


I always wear latex or nitrile gloves when handling the lens. They protect the lens, keep it clean, and provide nice grip, so the lens doesn't slip out of my fingers.

Re: Generating spare parts and a cheap easy lens center solu

PostPosted: Wed Sep 07, 2011 12:57 am
by dirktheeng
twehr wrote:
dirktheeng wrote:Then you have to work the last spring in place. I used an xacto knife to get it in there. Keeping the lens covered with your thumb when you work with it ensures that you don't scratch the lens (this is what i should have done).


I always wear latex or nitrile gloves when handling the lens. They protect the lens, keep it clean, and provide nice grip, so the lens doesn't slip out of my fingers.


Yea... we still have to clean the lens after touching it with gloves (at least we do at work). The gloves are never really clean. If you use some acetone with a q-tip it works well and leaves no scratches... juts don't press hard with the q-tip.

However, if the gloves fit tightly they do give a good grip without being cumbersome... if they are loose, the dexterity you loose is worse than the grip you get.

Clean hands are about the most gentle thing that you can use on optics as long as you do a good clean afterwards as long as you don't have to worry about a special coating or something like that.