Does RDCAM 5/Laserwork require a dongle?

[john banks]

Machine arrived today. I don't seem to have a dongle, not at the stage of connecting yet as it took four hours to get the machine out the crates and onto the floor, but when I run Laserwork it asks to connect the machine which suggests it might use that instead of a dongle?

A few other comments so far, will post pictures another day...

Ordered 1280 but the box said 1290, not measured it yet. The two RECI 100W tubes claim to have 115W on their test labels, and a quick glance in their boxes shows them to be well packed and apparently undamaged.

There are no covers for the front and rear slots, but that can be a first project to make some.

All the spares we ordered seem to be there but the longest focal length is 75 not 100mm.

Built like a tank.

Also there is a large compressor sprayed gold (2.2kW and 0.8 MPa!) with its own tank and gauge and taps, then a green tripod about three foot tall that looks like a part of a ship (massive bulkhead style bolts that look ready for some pressure), but it has what looks like a filter and a water trap attached to it. There is also a separate much smaller regulator and water trap. I thought I'd be receiving a little aquarium pump!

Some of the sticky pads holding the cables in place are adrift and some of the wires need a few nicks and bits of insulation added. There was an earth cable supplied but no earth post, and the earths are being taken from the mains supply connectors. There is good continuity between the earths on the mains connectors and the appropriate power supplies/casings, but earths with painted metal panels will be very tenuous. I will be looking more at this in the coming days and maybe ground any panels that are near to high voltage wiring in particular and make sure they are not flying loose near to moving parts.

Looking through the final mirror/lens I can see some swarf in the optical path, will need to work out where this is, but there is a route through the middle for the laser.

The red dot is through the mirrors rather than at the final mirror as requested. Will see how this goes.

[stan kern]

they normally protect by a dongle

[Rich Harman]

No dongle required however LaserWorks will not run if it does not see the laser attached. So.. the laser is the dongle.

[Khalid Nazim]

Congratulations. Get ready to be totally consumed. Its so much fun to make stuff. There is no dongle with RDCAM.

[Rodne Gold]

It is important you install an earth spike , a copper rod driven into the floor about 1m or so , tie all your grounds to this.

[john banks]

So even once Laserwork has seen the laser control board once it still requires it to start up? What if you disconnect once it is running?

Strange questions because this may require a rethink about what computers we put where. The idea was to do design work upstairs on a big monitor desktop, and only have a very old machine or USB sticks to the machine once the files were prepared in Laserwork, but if you can't run Laserwork on another machine then will have to migrate from cdr to Laserwork on a desktop or laptop attached to the machine. Is there much work required in Laserwork for a well prepared cdr file or is it just a few clicks and a preview?

I can't remember if the demo version (starts without a machine or dongle attached) of Laserwork lets you save files, I had installed it on a PC before I wiped it all but should be able to find the backup of it.

[Rich Harman]

If you disconnect while the program is open you can continue to use it. Every time it is started it will look for the laser.

If you have a spare motherboard you may be able to make that into a dongle. Haven't tried it myself but I am considering it.

[Rodne Gold]

The non machine linked version allows you to save files , the Demo version I have does however have some features not enabled....
Not so simple to one click import from Corel , there will be issues with lines with width and so on , however you can use the design puter to go as far as you can with the demo program and send via your network to the dedicated machine to do anything you cant on the design one. Sometimes , it's easier to actually use laserworks to design stuff if its simple.. definately much better to do arrays of multiple objects in LW than Corel.
By far the easiest way to get what you see on screen in corel for complex vector graphics that need to be engraved is to import em as a high def bitmap. We do a similar thing with our other machines that have corel print drivers , we run em thru photograv. Avoids unexpected surprises , like hidden vectors.
Not so sure the spare mboard would be that easy to hook up , it needs power and it reads and gets info from proximity sensors and such like.
I can tell you what will really help you , is to read the various versions of the manuals whilst experimenting with the machine , some stuff is covered better in other versions of the manual and the overlaps make a complete picture.

[Khalid Nazim]

In my experience, LaserWorks only needs to see the Laser the first time you start the program. Afterwards you can have the computer disconnected from it and use it only when you want to process something on the laser. In my setup, I have myself and my son use our laptops(not connected to the laser) to design stuff on CDR, export it out as DXF, import it in LaserWorks running on the laptops (still not connected to laser), set the cutting/rastering parameters, save the file which creates the .RDL files. We then copy these files on USB sticks and directly run the files on the laser or if we are not confident about our settings, connect the laptops to the laser and run the laser directly from the laptop. We have also connected a desktop PC to the laser recently so that we can just pull up the RDL/DXF files on the network instead of moving them around on USB sticks. We have Laserworks on the PC and we just open/import the RDL/DXF files on their and download directly to the laser.

Regards
Khalid

[George M. Perzel]

Hi John;
There are a lot of ways to approach this. Rich is correct-Laserworks needs to see machine to start.
My Setup: I have a separate computer with Laserworks on it attached to the laser. The puter is on a network. I do not use Laserworks for design work-too cumbersome and poor design tools, but great for certain apps as noted by Rodne. All work is done in CorelDraw. When I am done with a design, I save all of the raster and vector info on separate pages. I save the vector page as an Adobe AI-ver 8 file and save all of the raster info as a grayscale bitmap. I then send the bitmap and AI file to the Laserworks computer, open a new Laserworks file, and import the bitmap and then the AI file-lining them up if necessary and then grouping the images. Save the file as an .rld file.
Best Regards,
George
Laserarts

[Rich Harman]

What are the benefits of exporting from Corel into LaserWorks rather than using the Corel plugin?

[George M. Perzel]

Rich;
None-other than I do not have Laserworks installed on my design computer since it is not connected to the laser. Design computer is in an area with an atmosphere is much more conducive to creativity than the laser area-also closer to the coffee pot.
Best Regards,
George
Laserarts

[Rodne Gold]

Corel plug in is so the mnfgrs can say "it works out of coreldraw" , in fact it just "automagically" exports to laserworks. Advantage might be that its easier to amend in corel than have to re export , disadvantage is having to run a more potent puter to do Corel speedily.

[john banks]

Thanks guys. After the "day job" today, I thought I would fire up the computer side of the laser to test a few things, being certain I was connecting only that side so I didn't fire up the laser power supply with no laser tube LOL. All seems to work except some of the limit settings are a bit sloppy so that it isn't squared over the table area, but more importantly can crash into the front cover of the machine, especially at the right hand edge. I'll look for a software setting for this as it seems that the red limit sensor is at the back of the machine for this axis and presumably a dimension is in software somewhere. Also the plastic chain through which the air assist pipe runs manages to hit the top of the machine near the back (think I need to glue it down so it doesn't curve up as much), and the air assist pipe is not quite reaching the head. I'll try to feed through some slack on this pipe from its entry to the machine.

The table and head seem to keep a reasonably uniform distance in all areas of the table, by eye I reckon it varies by 1-2mm at most, but one or two of the knife blades are a bit bent from transit as they were not secured and have flown around inside the machine and were at all sorts of angles. Hopefully this shouldn't give a problem with focus on large jobs.

The Z adjustment is a bit rough sounding right at the bottom of its range, but it does move OK. This is using the rocker switch by the emergency stop, not double checked whether I expect it to move through the keypad or whether it isn't connected there.

Hope the feedback is useful for anyone else setting up to refer to in future, and some of you guys will hopefully have a few tips if any of the above prick your ears up.

Cheers,

John

[john banks]

Changed the vendor settings from 900 to 800mm and it stops the crash at the front. Fixed the plastic chain crashing and air assist pipe and hooked up my quiet 500W compressor before considering the big and noisy supplied ones.

Laserwork loads up now it has met the laser main board once, even when not connected, which will be great for flexibility.

Just need to attach exhaust, prime water/antifreeze CW5000 and align now, plus a bit more cable tidying.

[john banks]

The hose barbs on the water flow sensor leak. The actual metal is weeping, not where the hoses go onto the barbs or where the fitting is screwed into the body. I reduced it by filling the defects with solder, but will drain and strip it down and try to get replacement fittings.

The table is 1.5mm lower at the front than the back on more careful measuring. It is fine in all other directions. I wondered whether the front could be adjusted or shimmed, how/where is best?222162222163222164

The plastic chain crashing problem continues at start up or the back area of the table. Although my first reglue came apart, even if you clamp the chain to the rail as far along as you can go when it is at the right hand side, it crashes into the frame at various positions in the middle.

[Khalid Nazim]

The table height can be adjusted manually. The table moves on 4 screws - one at each corner which are connected via a belt which is driven by a motor mounted on the frame under the table. You should loosen the bolt on the plate under the table to reduce the tension on the belt. Then you can manually move the each of the screws to raise/lower that particular side of the table. Rich Harmen has written an excellent procedure to manage this on one of his postings. Search for that.

[john banks]

Thanks!

Any thoughts on the air assist/plastic chain crashing into the black panel as you can see in the photos where it is in front and behind the black panel it crashes into?

[Rich Harman]

The cable chain hitting is an annoyance but common for these machines. As you use the machine it should lose some stiffness. Mine does not hit as readily as it used to. I believe it is the plastic tubing and it's resistance to bending combined with the light weight of the chain that is the cause. A heavier chain might do better in this regard but it would increase the moving mass of the laser head.

[Rodne Gold]

Perhaps use a rubber band to "tension" the chain so it doesnt hit the lid , will have "give" and not really affect the performance of the chain.
You could put some of the soft foam double sided weatherstriping on the chain too , so if it does hit , its muted and non damaging/scratching.

[Rodne Gold]

One of the first things we did is ditch the "blade" table , We then checked the base table is level and just use the honeycomb or elevate stuff on blocks of perspex , yet got to work out what the blade table is good for..... maybe cutting...

[Dan Hintz]

yet got to work out what the blade table is good for..... maybe cutting...
Yep... you'll see it quite often on the larger (<cough>kiloWatt<cough>), more industrial lasers.

[Khalid Nazim]

Rodne, I rarely use the Honeycomb table and my standard table is the knife edge as I do more cutting than engraving.

[john banks]

Hopefully Jane has managed to get a new hose barb today and we can level the table and get the water flowing properly tonight to do a full alignment.

On a brief test before I noticed the leak, the beam was central at the first mirror, but offset at the second mirror. However, it was at the same spot when the second mirror was near and far from the first. Does this imply that the high voltage end of the tube needs to move or the first mirror?

I expect to learn a lot about alignment by doing it, but the red dot and the laser are not at the same point either, so the red dot will need adjustment where it is mounted I guess.

To clean the first mirror I'm doing it blind as I can't get my fat head in a position where I can see through the chassis cutout to see it and have been putting an IPA soaked cotton bud in there. I also wondered if I wanted to remove the red dot whether the extra attachment to the mirror would detach easily, but don't want to fiddle more than I have to before the machine is up and running properly.

I do have a laser output at the head already and at 400mm/sec (this was the max I could set it on the keypad, will look at software settings to see if it might go higher) at 25% power it rather impressively sliced into cardboard and had a nice sharp line. My "first cut" :)

[George M. Perzel]

I use only the honeycomb. I tried the knife table once for cutting-thin ply. Cut pieces fell at angles, head hit them and moved table and messed up rest of job. The table is one heavy mother -now used only to keep pile of ply flat-trying to sell blades on Ebay to vets for use in circumcising elephants-no takers yet.
George
Laserarts

[john banks]

You take out the whole table to fit the honeycomb?

[Rich Harman]

I don't use the honeycomb table unless I need to use magnets to hold something flat. My home made pin table is what I use almost exclusively.

[john banks]

Levelling the table is interesting. You can get it level in all corners, tighten up the z belt again and confirm it is still level in all corners. Then move the table up and down and it can be low in one corner again. A lot is trial and error. Might be worth greasing the jacks to make it run smoother perhaps, but the belt isn't skipping.

[Rodne Gold]

Look for a member here called vincent de klerk , msg him , he redesigned the whole table thing uses chains etc.
Remember one thing when leveling a table , and that is that the head must maintain its distance all over the table , you might level successfully , but have the head not maintaining its distance at some points , you basically use the head to "clock up" the table.

[Rich Harman]

If the belts are not skipping I don't see how the table can be changing it's levelness.

The method of attaching the table to the brackets was terrible on my machine. It caused the brackets to be angled down when weight was applied to the table, which would cause the brackets to bind on the jack screws. To fix it I bolted a steel bar that joined the left side bracket to the right and then bolted the table to that. Now the brackets are always perfectly level and cannot bind. I have not had a single problem with the table since.

Pictures in this post: http://www.sawmillcreek.org/showthread.php?166611-Chinese-lasers-they-re-here-!!!&p=1761562&highlight=#post1761562

[john banks]

Thanks. I am using the distance between the head and the table to level it. So I now have 9mm in three corners and 10mm in the last with the supplied presumably 50mm lens (9mm focus stick was ribbon tied to the head on arrival). I will play a little more with it, but what is acceptable?

[Rodne Gold]

It's really unlikely it will make a huge difference , I would shim the table up on that corner with a 1mm thick washer, the lenses supplied with the machine are 40mm unless you expressly asked for 50mm to be fitted. The 40mm ones work well , we cut 12mm acrylic with it quite nicely. dont trust the focus stick , rather check focus , lots of ways described in the forum, and make your own. We bought 50mm lenses for our Spirits and they arent the same focus points as our original one ... supposedly "imported" ones .. (all the yellow lenses from china are the "imported" ones , but I dunno , we were quoted $500 a lens from our GCC agents and the ones from china cost me $15....
Don't despair , once you over the niggles , the machines work real well , you will be smiling...till something goes wrong...but you got spares...
So far the only thing to fail on our 2 machines is a cheap 60w tube (operator error) and I suspect my 80w Reci isnt pushing its full potential but it's working well , so I wont scratch where it doesnt itch.
Pascal seems far less diligent than Blanca - but I think she can't interfere as Pascal is the North amerika "agent"
I've sp[oken to em about a western package , much much tighter QC and a sapres pack , but they so paranoid over pricing , they think this will scare ppl to their competitors , they need edukashin.
That cobined with a decent Corel driver and manual (I was going to re-write it , but lost motivation...maybe a forum collaborative effort would be good...) will make em king...
Penny wise , pound foolish is the best way to describe it all...........

[john banks]

Thanks. Not despairing, enjoying the massive saving and most grateful to you and the forum for all your advice and being the trailblazers with these machines.

Calmer waters will be lapping against the shores of matrimony when this is all setup ;)

[Rodne Gold]

Your attitude is right , positive and not raving on about the niggles , the best of all , those niggles FORCE you to learn your machine inside out ..

Here's a Haiku to brighten the day , not Chinese but what the hell....

Bright light issues
Tsunami of relief
Comes the calm after the storm

[George M. Perzel]

Rodne's not the only poet:
Behold the noble Hindu
He does all he kindo
Away up there with nothing to wear
he has to make his skindo

[Khalid Nazim]

9mm stick is for 40mm lens. I actually used x-axis bar as my reference point. I measured the distance between the bottom of the x-axis bar and the table and adjusted the height of the table. I dont think that a difference of 1mm across your large table should create a problem.

[john banks]

All working well after a big alignment session today. The tube still fires at 4.5% and engraves a line 80gsm paper, but is more consistent at 5% so you can't see a thicker line where the laser turned on initially. Increasing the speed from 400 to 800mm/sec in vendor settings didn't seem to make a difference to the speed when using the keypad controls despite doing read-write-reset.

5mm hardwood cuts great and easily at 85% power at 5mm/sec, even through knots and if the wood is warped. The kerf angles improve with the 75mm lens. Trying to work out what alignment I could improve if any to get them to improve a little with the 40mm lens. At the front of the table when I put a spot on card and then move the table down about 20mm and repeat, it drifts a few mm rather than being superimposed like it is at the back of the table. I thought this might mean that number 1 mirror needs adjustment, but the spots are superimposed at the inlet to number 2 mirror in all positions.

Still, the kerf angles are better with the 75mm lens than anything we saw from Epilog despite them sending away some of our wood to tech in the USA to have a go, and the worst with the 40mm are similar to Epilog's best.

It doesn't cut through thick oak even with the 75mm lens quite as well as the same power RF tube by GS laser, although they had much more powerful air assist and used two passes which I haven't attempted yet.

Filters in my extractor look brown instead of white, no haze in the room, but some smell, I think because the open slot at the front and my impatience to get the work out on completion doesn't help, but our extractor setup is noisy when everything else is quiet.

With alignment I did notice that there was effectively only one possible mirror position to make the spots coincide at both ends of travel on each axis. However, the spots are not exactly in the middle and it doesn't look practical to move the mirror holders to achieve this. It isn't far out, perhaps in places a third of the way across the mirror rather than bang in the middle. Perhaps tweaking the laser tube position might help more?

Overall delighted! Particularly pleased with the delicacy of this RECI tube. Amazed it works down to 5%, will have to see if it is consistent doing that over time.

[john banks]

Just done some engraving in cherry, Aztec calendar. It looks fantastic, tried 400 and 800mm/sec and power from 30 to 90%. At 90% it does a really deep engrave, amazing 3d look with lovely contrast, about 1mm depth from the look of it, no banding, no pixelation. Really impressed, can't stop looking at it :)

I have noticed that the ammeter peaks when the laser starts up, so if you are cutting at 90% it settles almost immediately to the 26mA the tube is supposed to run up to to get prolonged life, but the peak is for a fraction of a second higher. Presumably this isn't an issue? When engraving with up to 90% power the meter shows less as it averages out.

[john banks]

30mm/sec cutting of 4mm kiln dried hardwood which I think is cherry. Lots of playing with wood resulted in our scrubber clogging, so we are going to vent outside, the supplied 550W extractor doesn't seem too noisy (especially compared to our 1500W dust collector) but we needed to strip and rebuild it to stop the leaks. Tried the Shenhui supplied compressor (which is very noisy, metal, 2.2kW and not earthed, and will do up to 0.8Mpa) and oil/water collector/filter (which leaks) and ran it at 16 PSI (compared to 6 PSI from the 500W 420l/min aquarium compressor. Cutting performance or flaming on the 4mm wood was no different, so we'll run the quiet small aquarium compressor.

50mm squares of wood (don't have acrylic yet) cut with a decent kerf angle in all corners of the table. The size is 49.5mm. I guess when we try 100mm we'll look for 99.5mm and if not consider adjusting the steps.

Still delighted :)

[Khalid Nazim]

You can actually adjust the settings in the vendor setting menu to take care of the error on the x/y axis. I will post some pictures later to show that.

[Khalid Nazim]

Step 1:
Open File/Vendor Setting (pwd rd8888). Click Read. Click Save - use any filename (this is going to save the original vendor setup file that came programmed on your motherboard)

Step 2 - Adjust for the error.
Select x axis. Select Step Length (click on the 3 dots button) "...". In the dialog box, enter 50 in graph length and 49.5 in measuring length. Click Ok. Select y axis and repeat the same process. Then WRITE. Now you would have adjusted for the error on the machine.

See image attached for reference.


222756

[john banks]

Thanks. Would you recommend I correct to the size of the shape I cut out or the size of the surround from which I cut it?

I think I'm going to have to take the lid and top section off the machine and work on this panel where the air assist chain catches because the lid is also catching on it and making a horrible noise when the door opens, scuffing the paint as it does so.

Disabling the "enable home" means that the machine doesn't remember its position through a power cycle, so it will crash into its limits after being restarted in the non-home position. Also enabled the limit setting which means that if the machine does hit a hard limit in these circumstances it stops and throws up an error, but hopefully now that "enable home" is back.

On another note, I loaded up a .ai file I saved in CorelDraw from an .eps and Laserwork gave an error when opening. Also Laserwork doesn't seem to open a .cdr file, but it will open a .dxf when I saved in this form from CorelDraw. I just need to play with it more I think.

[Rich Harman]

Don't forget to account for the width of the material that the laser removes.

[john banks]

Micrometer ordered so we can get it precise.

Tomorrow I get up on the roof to install 6" ducting. This will let me relocate the exhaust fan up into the attic where you can only just hear it compared with the loud sounds in the workshop. With the small compressor up there will also take in cool air from there and this will mean we lose less heat from the workshop perhaps, but don't have to worry about filters clogging with wood smoke. The sound and smell outdoors are negligible whilst cutting wood and seem acceptable given our rural setting.

Below are pictures of a bracket we added to stop the chain crashing into the panel just behind the lid hinges.

222878222879222880

[Rich Harman]

Micrometer, or digital caliper? I just picked up a 12" digital caliper from Harbor Freight yesterday. The standard 6" was coming up short.

Seeing those pictures makes me wish I had ordered the knife table. Not to cut on, but to support the honeycomb. With the honeycomb directly on the flat aluminum table there is a whole lot of flash back. If it were raised up off of the aluminum table it would be much more useable.

[john banks]

222881
Not tried the honeycomb yet but the back edge of cut wood is perfect even with n00b complete guesswork on speed/power and only 5.5 PSI air assist. Of all the laser demos we attended before purchasing I only ever saw a nice honey color edge on laser ply, but it is also appearing on hardwood. So the guessing fairies (plus all the reading on here!) are working well.

Just a 6" digital caliper off ebay, will see how it goes. I know it is a fraction out in one axis as you can reinsert a 50mm square at its cut angle (tight fit) or 180 degrees, but at 90 degrees it is either loose or tight depending on whether I started with the tight or loose dimension. Very close, but I like precision.

Another thing I discovered, it is aero on Windows 7 (and presumably Vista) makes the menus in RDCAM draw the background slowly which makes even a fast computer sluggish. Disabling aero for this application by right clicking the shortcut and clicking properties, then checking the setting as shown disables aero just for this application.

[Rich Harman]

Aside from checking the step lengths, be sure to check for squareness. Mine required mechanical adjustment to get the x axis exactly 90 degrees to the y.

[john banks]

Thanks, good point. What did you adjust mechanically?

[Rich Harman]

The Y axis motor drives a torque tube in the back of the machine. You can loosen one of of the couplers and turn just one side of the torque tube by hand. Moving just one side will skew, or rather un-skew, the X axis relative to the Y axis.

The easiest way I found to check is to cut a rather large square out of mdf and check it with a large carpenters square.

[john banks]

Thanks, will investigate.

[Dan Hintz]

Micrometer ordered so we can get it precise.

Tomorrow I get up on the roof to install 6" ducting. This will let me relocate the exhaust fan up into the attic where you can only just hear it compared with the loud sounds in the workshop. With the small compressor up there will also take in cool air from there and this will mean we lose less heat from the workshop perhaps, but don't have to worry about filters clogging with wood smoke. The sound and smell outdoors are negligible whilst cutting wood and seem acceptable given our rural setting.

Below are pictures of a bracket we added to stop the chain crashing into the panel just behind the lid hinges.
Micrometer already questioned, so I won't go there...

But I hope you plan to use a quality moisture trap on that air line... pulling in air from a non-conditioned area may mean a lot of moisture, and the last thing you want for a healthy lens is condensation build-up. It also sounds like you might be planning on pulling in air from outside to use as vent air across the table... same warning.

[john banks]

Thanks Dan. Would a reasonable test be to blow the air onto a piece of glass by the machine to see how it performs? The glass of course wouldn't have a laser heating it up.

The area I could pull air from is an eaves cupboard from the office area above the workshop. The office area is heated and insulated, but the eaves cupboard is not, the cupboard doors are 1/2" wood without insulation and the compressor would be just behind them in there, when the compressor is running the laser would be in use and a bit of extra noise in the unoccupied office is fine. It would be relatively easy to pull air from the heated office room instead. The compressor isn't hellish noisy so I do have options. Interestingly the machine as supplied doesn't have any other airflow across the table, only input is from the air assist. The UK has high humidity, so warning heeded, will be careful. Thanks for the heads up.

Is the issue with the micrometer/caliper the size in that you can't tell the small errors, or is it quality of the cheap ones? At the moment I use a millimetre ruler, so this has to be an improvement.

[Dan Hintz]

I think the issue was the difference between calipers and micrometers... you want a set of calipers (generic ones are good to 1mil, as in 0.001"). Micrometers, on the other hand, are 3 orders of magnitude greater accuracy, but are really meant for measuring different things.

[Rodne Gold]

Laserworks has a kerf width compensation setting
Double click the layer/colour in the work tab and the cut parameter screen comes up , click on the advanced tab near the bottom and the "other cutting parameters " dialog comes up , you can compensate inward or outward by whatever amount you want. (they call the kerf the "sew width")

[Khalid Nazim]

Oh that's what this is for? What is the kerf width for an 80 W RECI laser using a 40mm lens?

[Dan Hintz]

Oh that's what this is for? What is the kerf width for an 80 W RECI laser using a 40mm lens?
Probably on the order of 7mils (maybe as low as 5, if you're lucky), but you'll want to measure it to be sure.

[john banks]

Got the 6" extraction up behind the wall and through the attic and put a chimney on the roof with nice parts, too dark now to photograph, but pleased with it, became an involuntary roofer following January storms so got quite familiar our old clay pantiles. No small job as it is around freezing but in the daytime the frost has been thawing nicely, but the extraction arrangement is nice and quiet and pulls well. There was a few square inches of gap around where the extractor pipe runs out the workshop into the wall, tomorrow we were going to cut a ply or MDF surround to make it neat. When the exhaust is on there was a considerable draft, but not due to a leak as it was coming into the room as shown by putting the edge of a sheet of paper over it, a leak on the suction side would have pulled the paper in. Opening the door 30 feet away quickly made it stop. Conclusion is that the extraction through the machine (which still has the front and rear slots open) is taking a lot of air out of the room as you guys had previously advised. We'll fill the gaps in the machine and the wall and try to assess whether the room gets much negative pressure compared to the outside. However, at temperatures about freezing (which is about as cold as it has got this winter so far), to heat the air to a comfortable level will take (back of envelope calcs ignoring humidity effect on heating air and heat from machines heating the space) an extra 4000W when the extractor is running. Balancing that is that this extractor uses 550W instead of 1500W so there is an energy saving there and without the filter the smaller pulls better. So a net change of +3000W in winter and -1000W in summer. Net effect is 2kW extra heating when the extractor is running which based on 25 hours a week over 45 weeks a year that is £225 a year extra electricity costs. That probably balances the costs of filters etc.

[john banks]

Things are going well. New extraction working great with no visible smoke or smell outside, and very quiet in workshop. Not a disaster to heat. Compressor is also remote now with no obvious pressure or flow loss and the eaves cupboard seems to be much drier than outside as when there is freezing fog outside, things seem great at the compressor, water trap and lens.

Sealing where the vents come through the wall has helped, as has temporary pieces of bath panel to reduce the area of the front and rear slots.

Jack screws oiled which has helped and now the table stays level. Have been using the final mirror to get the beam central at the head and then adjusting the head mount to get it all vertical by making marks at various table heights. On the 40mm and 75mm lenses kerfs are great. 7mm hardwood cuts at 10mm/s but that rises to 30mm/s for 4mm so 4mm seems sweet.

Will fiddle with engraving as when engraving text it looks like the edges are not perfect but other non-text engraving looks great.

Jane is doing well with the machine when I went back to the day job and is enjoying her new adventure.

[Rodne Gold]

You need to do bidir compensation to get lettering 100% , you need to do it at a slow spped , a mid speed and a high speed and then the machine will interpolate all other speeds.

[john banks]

Thanks.

I noticed that when we received the machine, the convex side of the lens was pointing down. It appears to be planar and one side and convex on the other. The manual and other information I read suggests it should go the other way so that the convex side is upwards. I tried this but actually the cut at the same power is not quite as deep, so it has gone back on again the wrong way around.

I also tried removing the red dot and the mirror with it, and there was no obvious effect on cut depth at the same power, so it has gone back on again.

[john banks]

Can anyone identify what the two types of lenses I have are? Most including the standard one are yellow (ZnSe?) and the red dot passes through. Two are green/blue and reflective to visible light like a mirror and opaque to the red dot. Are these ZnSe or GaAs? I asked for GaAs but was told they weren't available.

[Dan Hintz]

Flat side towards the substrate... and you'll want to find the new focal point.

[john banks]

And that has helped, thanks. The focal point for best cutting was 1.5mm closer than the supplied focus stick.

[Ed Arroyo]

Quick question and I need some help:
I'm new to laser engraving and I purchased a Chinese 50w laser from a family. The person who previously used the laser passed away and the family had everything except the following:
1) focus lens ruler
2) software disk

How can I get a copy of Laserworks and a focus lens ruler?
The manufacturer has been no help since I did not buy the machine directly from them.
Any assistance would be greatly appreciated.

Thanks,

-Ed-

[Dan Hintz]

You can make your own ruler. Find the proper focal point of the system, then cut your own out of acrylic. Place a piece of painted or anodized aluminum at an angle on the bed (one end touches the bed, the other end is propped up about 1/2"), and set your estimated focus to roughly the middle of the sheet. Laser a line from the low end of the sheet to the high end... the sharpest part of the line shows you where the actual focal point is, so set your machine to that point from now on.

[Khalid Nazim]

When using this method of determining the correct focal point with the material at an incline how would you measure the distance accurately between the point on the material which is the sharpest in focus and the end of the cone? I have just placed a ruler vertically on the spot with the sharpest focus and then eyeballed the distance between the cone and the material. Is there a better way of doing this?

[Dan Hintz]

Math. Let's say the end of a 10" sheet is propped up by a 1" spacer. If the best focal point appears to be 5.5" up the sheet from the table, that says the best focal point is 0.55" higher than the table is currently set to.