Have I messed up my lens already?

[Jiten Patel]

So been using the speedy 400 for the odd job and lots of testing. I cut a job of some small wood pieces (veneer MDF 6mm) and cleaned the lens before the job. After the job, I cleaned the lens and have this spot on it which won't come off. Now I know some people have mentioned using vinegar and other things to get it off, but don't really want to use something that will further mess it up. How do I clean this thing up?

Thanks

Jit266579

[Dan Hintz]

It looks salvageable, but you may have ot putt a little elbow grease into cleaning it. Any darker and I would say the lens is damaged. Clean using your normal method, but this time you won't get away with wet-and-drag, you'll need to do some rubbing with the Q-tip.

[Scott Shepherd]

I agree, I think you are fine. Could be damaged, but I've done a lot worse myself and it's come clean. Make sure you don't run the machine with the nose cone on and the air off. That'll cause what you see there. Not saying that's what caused it, but it will cause a serious issue. Air On- Nose Cone On. Air Off- Nose Cone Off is my rule.

[Jiten Patel]

What would cause that after only an hour and half of cutting?

[Dan Hintz]

It's an avalanche process... once a small amount of residue sticks to the lens, that area heats up, which allows more residue to stick, and so on.

[Jiten Patel]

Thanks guys. Nose cone was on, air was on....so not sure where I went wrong. Is it a point of just scrubbing hard for ages?

[Dan Hintz]

Think of it in terms of many many light strokes rather than a few hard ones. You want to soften that residue without scratching the lens.

[Jiten Patel]

Got it, thanks guys...really appreciate it. Will post up when I get it off!

[matthew knott]

I would avoid scribing hard as the AR coatings are fragile, I have used distilled vinegar ( the clear stuff) to great effect on dirty optics ! There's a company near me in Stevenage that sell new optics and cleaning kits, they make the highest grade optics and are pretty helpful if you need optic advise (umicore)
hope you can recover it Jit, how are you getting on with new machine?

[Jiten Patel]

Guys you are brilliant! All done - just some elbow grease needed. I was worried about scrubbing too long just in case I scratched it as my galvo would never get build up like this as it is too far away from the bed. Thanks again 266583

[Scott Shepherd]

What would cause that after only an hour and half of cutting?

Insufficient air flow on the exhaust. I had that for a while and I could not keep my lens clean. Upgraded my exhaust for it and it immediately resolved the issue.

[Jon Colley]

If you haven't done so already, I would pop off the bottom cover at the back of the unit and make sure the air assist valve is opened up. If it was already wide open, stick with the nose cone that has the smaller opening for higher air assist pressure.

[Jiten Patel]

Right, so I will turn up my air assist. The exhaust is a Trotec atmos, so should have sufficient air flow should it now? The thing is built for these machines?

Matt, getting on great. Love playing with it....far more complicated than the galvo's that's for sure. So many things to think about before running a job, but I guess it will become second nature with practice. Got hundreds of product ideas, just trying to source everything I need to make and package them and we are away. The second business should be launching Jan 14 if all goes well. Lots of R&D to do...which means lots of £££!

Jon, thanks for the advise....not sure what you mean by opening the back of the unit and the air assist valve....do you have pics?

[Tony saunders]

Mmmn - interesting thread!
I just took delivery of my new Speedy 400 yesterday. I'd had a 300 since the beginning of the year on loan and cut LOADS of MDF (which is messy!)

Anyway, I used the vacuum bed with the 400 - first use - engraving (actually light vector cut lines) on 2mm MDF - job ran for 100mins. it was only when it was trying to run the 30 second cutout that I noticed it wasn't cutting well at all...

The 2.0" lens is absolutely ruined!!!...

I noticed that the air assist was off in Job Control, but to be honest after many many similar omissions with the 300 - nothing like this has happened before! It looks like a new lens - I've tried cleaning / soaking etc...

Bit of a blow after only a couple of hours use :(

I'm using an out-to-air kit - 1.5KW blower with a 150mm pipe and a 'T' off to the vacuum port on the machine... (all Trotec Supplied)

Gutted!!!! :confused:

[Dan Hintz]

At least it;s a relatively inexpensive resolution, Tony... imagine if you had let a fire run unabated in the machine. That would have hurt a bit more.

[Tony saunders]

At least it;s a relatively inexpensive resolution, Tony... imagine if you had let a fire run unabated in the machine. That would have hurt a bit more. True Dan.. Over the weekend I've been using the 4.0" lens and watching it carefully. I'm definitely of the opinion that the exhaust isn't doing a good enough job clearing the smoke / fumes. I've had to tape off over half of the back vent in order to get the same sort of flow I used to get on the 300. That's no good if I'm using the whole bed though!

[Michael Reilly]

Yes, always run with the built-in air assist (assuming yours has it) and with the cone on. That positive pressure air keeps debris off the lens. We misplaced our cone once while cleaning and ran without it while engraving some acrylic on our Speedy 500 and like you saw, it tapered off, and when we looked, the lens had build up on it and was cracked.

More recently, we were using high pressure air assist from our main compressor and even though it goes though a self-draining water separator at the wall and then 3 more separators in the machine itself, the first of the three was self draining but clogged and all three filled up completely. Since this is behind a machine side panel, it wasn't noticed. This lead to it spraying water and oil onto the lens. When I tried to clean it, it cracked.

While the lenses are from the company II.IV, I found the cheapest replacements at Clear Beam Corp which makes the lenses for Epilog. I get 2.5 plano convex lenses for $190 plus shipping vs $300-400 elsewhere. I've seen no difference in performance. I just bust the old lens out (it shatters into dust) clean out the glue and glue the new one in place with jewelers glue.

[Tony saunders]

Hi Michael,

Interesting - thanks for posting that. Exactly the same issue - lens absolutely ruined. Trotec to be fair, provided me with a new lens FOC.

JobControl X interestingly always has the Air Assist OFF by default?!?... surely it would be preferable to be ON by default. It's easy if building up a list of material settings to forget to change this on the drop down.

Speaking to the tech guys today, it seems that the out-to-air units are 3 phase and rated to provide extraction and also a vacuum take-off for the vac table. Since we don't have 3 Phase, I have been supplied with a single phase pump and it appears it's not upto scratch for the job.

QUESTION to anyone: - Trotec have asked me to see if I can source a pump externally from another supplier that will work and provide appropriate suction comparable with the ATMOS system. If I can, they'll credit me with the cost and take the one supplied back. Has anyone got any recommendations as to a suitable single phase pump (out-to-air) - no filters needed where we are. If not, perhaps a 3 -phase pump that can be wired for single phase operation with appropriate motor-rated capacity??

Thanks in advance -

Tony

[matthew knott]

You need to get the Spec of the 3 phase motor they use, you might be able to run it with an inverter, if you can't because a single phase supply doesn't have the juice to run said motor I would be skeptical that you will find a single phase motor that will do the job. Seems a bit 'passing the buck' ish, I cant see how its your job to source anything, get them to do it.

[Jiten Patel]

Can they not upgrade you to an Atmos. We use one of those and have no issues with suction or smoke build up.

[Tony saunders]

You need to get the Spec of the 3 phase motor they use, you might be able to run it with an inverter, if you can't because a single phase supply doesn't have the juice to run said motor I would be skeptical that you will find a single phase motor that will do the job. Seems a bit 'passing the buck' ish, I cant see how its your job to source anything, get them to do it.

Yes, I thought that myself!... however, I am impatient to get this behind me so I can get on and use the machine properly so i have been having a look around. If I have no luck, I will bounce it right back in their court.

[Tony saunders]

Can they not upgrade you to an Atmos. We use one of those and have no issues with suction or smoke build up.

Where I live (and work) is quite remote so I can get away with an out-to-air which is cheaper to run re: filters etc.
I did have a loan BOFA unit with the Speedy 300 and was getting through so many filters (cutting MDF!)

What do you cut with yours Jit? are you finding that you get through filters at all?

[Michael Kowalczyk]

Tony make sure the motor is "continuous duty" rated. I use the 3 hp impeller section from an extra blue tornado cyclone system I had. I bring a 6" pipe down to the laser and split it with a 4" Y with blast gates on both 4" inlets. One feeds the back exhaust and the other comes from underneath so I can have a vacuum table also. I can adjust the amount of CFM with the blast gates. Works great and I do direct vent into a ceiling mounted vent in a commercial tilt wall building. You may find a good deal on a dented or used cyclone system and just use the impeller portion to get your air extraction.

[Jiten Patel]

Tony, we mainly cut card, acrylic and on the odd occasion MDF. Our filer is hardly used to not too worried about it and as we are close to residential, it was essential for us due to the smell of wood and acrylic. Our of curiosity, how much did you pay for the replacement filters?

Why not pick up a cheap dust extractor from Machine Mart, or try the inline fans if noise is an issue that quite a few people on here use. Very quiet and supposedly work a treat.

[Dave Sheldrake]

Very quiet and supposedly work a treat.

They are great Jit but do need to be sited close to the extraction point or as Dan mentioned they just don't have the ooommppff to pull much in the way of static air. More than 2 feet of hose and they drop in efficiency very quickly although up to 6 can be daisy chained to increase pull :) as you say though, VERY quiet compared to the MM 1.5HP models.

best wishes

Dave

[Tony saunders]

Tony make sure the motor is "continuous duty" rated. I use the 3 hp impeller section from an extra blue tornado cyclone system I had. I bring a 6" pipe down to the laser and split it with a 4" Y with blast gates on both 4" inlets. One feeds the back exhaust and the other comes from underneath so I can have a vacuum table also. I can adjust the amount of CFM with the blast gates. Works great and I do direct vent into a ceiling mounted vent in a commercial tilt wall building. You may find a good deal on a dented or used cyclone system and just use the impeller portion to get your air extraction.

Thanks for that info Michael - I will have a look later tonight once I've cut all the grass. I didn't realise until I started looking at this subject how much depth there is with extraction. I confess I thought it was much more straightforward... but like most things, it ain't quite so :)


Tony, we mainly cut card, acrylic and on the odd occasion MDF. Our filer is hardly used to not too worried about it and as we are close to residential, it was essential for us due to the smell of wood and acrylic. Our of curiosity, how much did you pay for the replacement filters?

Gotcha... well, MDF is NOT pleasant and very messy. Oily residues / noxious smell - the works! - the upside was that it is cheap and plentiful.

I didn't pay so couldn't tell you. Trotec loaned me a Speedy 300 with this filter unit when I placed my Speedy 400 order in January this year and they weren't available yet. Trotec kindly sent the 300 out and I had a great day with one of their engineers. The two types of filter it had were a cardboard 'concertina' square primary filter and a secondary heavier, metal-cased charcoal (I think!) unit about a foot high.

I got through the primary filter each week and the secondary one several times inside about five weeks!

Trotec then loaned me an out-to-air kit (which I wanted anyway) and it probably saved them a lot of money in filters.

Top marks to them for their support!

Cheers
Tony

[Mike Lysov]

I run a 2HP two phase blower with my 280W laser with 8" inlet and outlet. It has been supplied with the laser.
It gets all smoke and dust out even when I cut 18mm thick MDF so you can imagine how much smoke I get.
I do always run it with air assist on, about 60 PSI. It should be 70 PSI but my air compressor cannot run for a long time supplying so much pressure and I have set it up at maximum of 60.

And the laser has quite a big bed too, it is 1300x900mm.

The other blower I have is 0.5HP and I run it with a 100W LaserPro and 35 PSI air assist for cutting up to 6mm thick MDF.
It does the job but sometime it cannot take all smoke out straight away.
It was doing it much better when it was new. I think it's just very dirty inside and I need to clean all tubing and the blower itself from residue.

[Tony saunders]

I run a 2HP two phase blower with my 280W laser with 8" inlet and outlet. It has been supplied with the laser.
It gets all smoke and dust out even when I cut 18mm thick MDF so you can imagine how much smoke I get.
I do always run it with air assist on, about 60 PSI. It should be 70 PSI but my air compressor cannot run for a long time supplying so much pressure and I have set it up at maximum of 60.

And the laser has quite a big bed too, it is 1300x900mm.

.

Sounds like your 2HP blower works a treat Mike.

In the end I have put it back with Trotec. The (initial) plan they have come up with is to possibly have a separate vacuum pump and are speaking to a third-party about solutions for the exhaust. As soon as I have anything of interest I will post back.