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Michael Ramsey
08-19-2017, 4:26 PM
Greetings all. New to all of this and have a question or two.

Looking to start up a small part time business. Mainly a hobby really. Long story short if I had my druthers I'd have a small wood working shop with a can but alas I just don't have the space at my current home for a proper shop and I am not giving up my garage. My next best solution is a laser that fits in my office at home.

The laser I am looking at is the Rabbit Laser RL 60-6090 and the Rabbit Laser RL 80-6090. I plan to primarily use wood, paper, corrugated cardboard perhaps some occasional acrylic. I really don't see cutting thicker than 1/4" material but 3/8" might come I to play. I would also engrave on some of these materials as well as glass bottles etc.

Some of my reading would indicate the 80 watt may be destructive on some low power intricate cuts / engravings. Does anyone have some examples of what those might be? Also interested in user thoughts on these lasers. My main draw is that they are in Ohio as am I.

John Lifer
08-19-2017, 7:31 PM
Corrugatted isn't a good material in my opinion for a laser, the voids can cause flare-ups and won't cut consistently, but I've not done a lot. Others may have solution. I've a 80 watt, and for low power I tend to struggle at getting proper settings and good outcomes. 60 might be better for Engraving, really depends on what you tend to do. Others will comment, not really a bla ck and white answer.

Dave Sheldrake
08-19-2017, 10:25 PM
1/4 is the sensible limit for any budget priced laser if you want decent quality or production speed.

80 watt is fine for small cuts (the spot is actually smaller than a 60 watt) but the problem *could* be being able to set the power low enough (10% of 80 watts is 8 watts, 10% of 60 watts is 6 watts)

To be honest I'd probably go with the 80

Kev Williams
08-20-2017, 1:51 AM
My 80w RECI has never proven to be to much power for what I do, but I can see where 100w or more would be...

at 70% power entered, my meter hits a dead-on 26mV, which I assume is close to 80w, and if 70% is actually 100%, that's a factor of 1.43 to add to my power % entered to calculate watts...

With my 40w LS900 I run black/white rowmark at 60% power, which factors out to 24 watts, and 80% speed comes to roughly 1460mm/sec...
The RECI I run blk/wht at 15% power at 700mm/sec., 15% x 1.43 = about 21.4% of 80w, which comes out to just over 17 watts. Factoring half the speed the 17w is applying about 34w in the same space and time as the LS900, and the assumption that 24 RF watts is more efficient than 34 DC watts, then it does come out roughly equal...

(hope that was clearer than mud! ;) )

The RECI will fire reliably at 8% power, 8x1.43=11.44% of 80w = just over 9 watts...

I actually don't know if it'll fire reliably at much lower than 8%, I know it WILL fire at 6%, but I've never done a 'reliability test' at 6% :)

Michael Ramsey
08-20-2017, 10:22 AM
All good info! I think I would say for certain that the 85% majority of what I intend to produce will be on wood. That being 1/8 - 5/16 ply and hardwood. Carole @ RL seemed to think that as log as I was not trying to engrave fonts smaller than 6pt the 80 would be fine. From my reading and limited understanding I believe the 80 RECI tube to be a superior tube over the standard 60w. I am sure that is somewhat dependent on the use case. My fear with the 60w for cutting is that I would make it work much harder thus shortening the useful tube life to some degree.

Kev - If I use your example of firing reliably at 8% ~9 watts can you give me an example of what materials or types of work where that might be used?

Doug Fisher
08-20-2017, 11:12 AM
The quality level of the power supply is going to be a factor in this too. If the RECI tube is genuine and comes with a genuine RECI power supply, an 80w tube will probably engrave well. I would expect this would be what you would receive from a reputable dealer such as Rabbit USA. With other dealers who might be looking to cut corners, that may not be the case.

Michael Henriksen
08-20-2017, 11:17 AM
You can see in my signature what tubes I have in my machines. The 80W is a really good compromise between cutting and engraving capability. They are also very affordable. With the 100W I sometimes struggle to go fast enough on cutting jobs in thinner materials. I upgraded from a std. 60W to the 80W RECI and it was a big improvement IMO.

Bert Kemp
08-20-2017, 4:05 PM
You won't go wrong with a Rabbit Laser I have a 60 watt and it works fine for me but if I had to do over again I'd go 80 watts as I do a lot of cutting. 1/4 Baltic birch I cut ok but its slow about 10 mmps

Michael Ramsey
08-20-2017, 6:40 PM
You won't go wrong with a Rabbit Laser I have a 60 watt and it works fine for me but if I had to do over again I'd go 80 watts as I do a lot of cutting. 1/4 Baltic birch I cut ok but its slow about 10 mmps

Thanks Bert, That's just what I needed to hear.

Kev Williams
08-22-2017, 2:05 AM
All good info! I think I would say for certain that the 85% majority of what I intend to produce will be on wood...
Kev - If I use your example of firing reliably at 8% ~9 watts can you give me an example of what materials or types of work where that might be used?

I did this quick test before running my next batch of cowbells, I just draped some done-with customer prints over the bell clamps, focused the lens to it and this is the results--
first off, the paper is lying a bit, I typed 8% but turned it down and ran it at 7% power, and 500mm/s. Gap space was .08mm, and I used a 3" lens...
first shot shows the paper, not really flat, 2nd shot shows the results, note the power fell off at the "8%" where it was a bit out of focus.
It does show that the power is pretty low--
366553366554

So I drew 3 quick rectangles, and cut them at 300mm/s and 7% power, with both MIN and MAX settings at 7%-
I did this on purpose, I'll explain shortly...
1st pic was during the cuts (had to act fast with the camera!)
366555

And here's the cuts. Now, notice the corners are cut thru, but not the long straightaways--
366556

I turned the paper over to better show this--
366557

--the reason I set the MIN and MAX settings the same was to explain what these settings are for, as many people don't seem to really know--
The corners cut thru is because the machine was in the process of decelerating toward the corner to change direction, and then acclerating away from the corner. During this time the machine is obviously running slower than 300mm/s, BUT THE POWER REMAINED THE SAME-- so the corners burned thru-
--This is what the MIN power setting is for, to lower the laser power when it's in decel/accel mode. Had I set the MIN power to around 5% (roughly 70% of 7%), the burn thru would have been much less or eliminated. However, at this low of power setting, the laser may not have fired at 5%.. So the trick is to experiment at 'real' power levels, such as vector engraving outlines in wood, change up the MIN power setting until the burn around the entire square is nice and even. Make note of the percentage differential, and use that as a starting point when vectoring at other power levels...

Western machines take care of this problem automatically. I would guess some Chinese machines may do this to some extent too, but I know mine doesn't!

That all said, as you can see, I can set my 80 watt machine to where it won't cut thru paper! --barely! ;) -probably a bit tougher task with a 100 watt+ machine...

Bert Kemp
08-22-2017, 12:48 PM
On my Rabbit and I'll assume the one the OP is looking to buy from Rabbit, there is a corner power setting, so you can actually change that power up or down as needed.

Michael Ramsey
08-23-2017, 2:52 PM
On my Rabbit and I'll assume the one the OP is looking to buy from Rabbit, there is a corner power setting, so you can actually change that power up or down as needed.
Yes I am actually looking to get the RL-80-9060. Gotta go with the RL so I can get it into the basement.

Michael Ramsey
08-23-2017, 2:54 PM
Thanks for that test Kev


I did this quick test before running my next batch of cowbells, I just draped some done-with customer prints over the bell clamps, focused the lens to it and this is the results--
first off, the paper is lying a bit, I typed 8% but turned it down and ran it at 7% power, and 500mm/s. Gap space was .08mm, and I used a 3" lens...
first shot shows the paper, not really flat, 2nd shot shows the results, note the power fell off at the "8%" where it was a bit out of focus.
It does show that the power is pretty low--
366553366554

So I drew 3 quick rectangles, and cut them at 300mm/s and 7% power, with both MIN and MAX settings at 7%-
I did this on purpose, I'll explain shortly...
1st pic was during the cuts (had to act fast with the camera!)
366555

And here's the cuts. Now, notice the corners are cut thru, but not the long straightaways--
366556

I turned the paper over to better show this--
366557

--the reason I set the MIN and MAX settings the same was to explain what these settings are for, as many people don't seem to really know--
The corners cut thru is because the machine was in the process of decelerating toward the corner to change direction, and then acclerating away from the corner. During this time the machine is obviously running slower than 300mm/s, BUT THE POWER REMAINED THE SAME-- so the corners burned thru-
--This is what the MIN power setting is for, to lower the laser power when it's in decel/accel mode. Had I set the MIN power to around 5% (roughly 70% of 7%), the burn thru would have been much less or eliminated. However, at this low of power setting, the laser may not have fired at 5%.. So the trick is to experiment at 'real' power levels, such as vector engraving outlines in wood, change up the MIN power setting until the burn around the entire square is nice and even. Make note of the percentage differential, and use that as a starting point when vectoring at other power levels...

Western machines take care of this problem automatically. I would guess some Chinese machines may do this to some extent too, but I know mine doesn't!

That all said, as you can see, I can set my 80 watt machine to where it won't cut thru paper! --barely! ;) -probably a bit tougher task with a 100 watt+ machine...