Goot cutting!

Today I started cutting some Plylite that I bought from http://www.javis.co.uk/. This is 2mm thick and I cut some welded words quickly and effectively using this material. Speed 20mm/s and 8A did the job in 4 passes.
I have found a good source of cleaning materials for the lens. A friend of mine gave me some cleaning packs for cleaning my spectacles. These contain isopropyl alcohol and keep my lens clean very well.
I am going to put a small patch of rubber on the tops of the adjusting bolts of ly adjustable table to reduce vibration being transmitted to the work. This is important when doing multiple passes to stop the work moving on the honeycomb!
I seem to be getting more success and I keep a note of the speeds and current on every cut I do to aid setup for future jobs.

Good and bad!

I have been cutting for a while now and I find that the water needs to be changed about once a month. I am using disstilled water but I find that after a while it goes all gloopy so I have to chuck it away and replace. I have been wondering wether I should add something to it like anti-freeze to try to limit this happening.
I have been cutting 2 and 3mm thick acrylic and found that the finish of the cut edge is really good. I have been cutting 3mm acrylic on 10m/s and 11 on current.
I have been cutting some 0.8mm thick plywood but I have to do 3 or 4 passes to get a decent cut without excessive blackening of the ply. Cutting 3mm MDF gives good results. I use cereal box cardboard for my test cuts and that cuts really nicely. I have found that when cutting intricate letters I have to slow the speed down otherwise vibration in the machine makes  the work move on the honeycomb resulting in scrap!
Before I cut anything I set the distance to the work using a digital readout vernier so that I get a good result.
THE BAD
I replaced the base plate with a sheet of plain aluminium and added stops to ensure the work was always at the origin. It now looks like one of the limit switches has moved as it does not go back to the origin correctly so now I have to work out where the limit switches are and how to adjust them!

Ongoing Reliabilty

The machine has been working tolerably well of late so long as I keep the lns clean and the cutting height correct. Yesterday I changed the cooling water and I am using ditilled water to cool the laser tube.
However; I heard a slight cyclic noise when the macjine was operating and now the origin seems to have shifted by about 6mm. Very irritating as previously I could place work on the table against my origin stops easily. Now I have to locate the origin manually.
I have found that cutting 2mm acrylic gives a really nice finish and I have not had any problems with the platic welding itself back together s I did with polypropylene.
I have improved my knowledge of Coreldraw, in particular, with respect to lining the obects to the edge of the page. I find this makes it easier to position the work for cutting.
I have been cutting mainly paper, card and MDF but have also lasered a design on th back of my mobile phone and then filled the dessign with acrylic paint to give a better appearance.

Work positioning

I put some tape near the origin and then ran the laser cutter along the X an Y axes to show the 0,0 point. Then I cut some square section aluminium tube, drilled it and then positioned over the tape and spotted through onto the aluminium bed. I then drilled and tapped the bed with M6 and bolted the tube to the bed.
Now I can palce my work at the origin repeatedly and get the cut correct every time. I realise you could do this with a red laser dot but I don't have one and this seemed the simplest solution.

Working well but the odd problem

Having changed the bed for a sheet of flat aluminium and put in an adjustable table, things are going well. I am using honeycomb to put the work on and that works fine. However, when cutting white card or paper, I get a browny/orangey deposit left on the honeycomb which sometimes is transfered to the work. Not an issue for some things but for white card, not pretty!
I am cutting hardboard, MDF and thick card bjut need to do several cuts to avoid a very blackened cut surface. I keep a record of speed, current, material and thickness for every cut I do so that it makes setting much easier.
If anyone has any helpful tips on anything I have raised, then feel free to post them.

Learning about marking and cutting

For some time I have been trying to engrave something and then cut out afterwards. With previous software and machines, it was a case of making various layers visible or invisible. However, yesterday I got it cracked with this machine and the Corel software.
I put the engrving/marking on one page in Coreldraw and the cutting on a different page. Then I ran the engraving, then ran the cutting after the engraving had finished and hey presto, success.
Shortly after, the fuse went on the machine and everything stopped.This time I knew how to change the fuse and a few minutes later the machine was working again. It doesn't inspire confidence for the machine to blow fuses occasionally. So while the machine is cheap, I would say if you were thinking of getting one make sure that you have a warranty that actually is effective. <the crew I got this machine from are useless and had no interest in solving the very real problems that existed.

Making Progress

I have been using the machine and learning more about it. Cutting 1mm thick card works really well and I am cutting at current setting of 10 and speed of 25mm/s. Results are good. I have cut paper and have achieved good results. However, cutting corrugated cardboard has not been successful. It may be that I have been laying it on the bed and the focal length is not correct, so I am oing to experiment and will probably make and adjustable height table. I have ordered some 3mm thick aluminium sheet for the bed and I have bought some honeycomb so soon I will modify the machine so that at all times, the surface that I am cutting is the same distance from the laser lens.
I have cut some foamboard with satisfactory results and also cut shiny gold paper by cutting mirror image on the reverse side.
I have been cutting welded words from card very successfully and now I want to try engraving rubber stamps. I have ordered some laserable rubber so when that arrives I will try it out.
The machine is set to 1000dpi and the speed seems to work OK now.