Ultra foam 1"

[Robert E Mason]

Hi all,

quick question about 1" ultra foam, it's a light urethane foam core with a stiff surface on each face. I've never cut it before but a client wants some lettering cut out of it (with a metallic vinyl on the top surface that they have applied).

I'm using a 60W Speedy 300 and guessed a power/speed figure of 50power 3.0 speed and 500dpi. It didn't quite cut through so dropped speed to 2.6 and it cut through fine BUT the inner foam core of the board had pretty much melted away.

Been trying a few different setting and now running 10power, 1 speed and doing approximately 10 passes with a short cool down period between passes. This is cutting the material, with minimum melting but as you can guess it's going to take an age to do the job and no way the client will want to pay the price for the job.

Does anyone have experience with this material being laser cut?

I'm swinging between giving the client the full cost with the expectation that they will decide against it or just give them a "happy" price as the laser isn't crazy busy right now and choosing between a $150 for me pressing "go" every 10 minutes and $0 with the machinee sat idle seems a no-brainer (my business is making scale architectural models and I'm currently sticking stuff together as opposed to cutting). If I went the "happy" price route I'd tell them I'll do it this once but if they want it again it's going to be crazy expensive.

thanks in advance

[Chuck Stone]

what about bringing up the power to 100? That should allow you to also
bring up the speed, which should help eliminate the melting.
Or am I missing something?

[Robert E Mason]

Thanks for the reply. TBH I never even thought of that, Monday morning brain fog! Will go give it a go.

[Robert E Mason]

Ok, tried 100 power with 6 speed. Same melting problem as before so upped speed to 12 with several passes (again with a cooling pause between each pass). Also, I have air assist on all these cuts.

See attached image.

Top part:50 power, 2.6 speed cut through the material in a single pass, heat generated by the laser badly melts the inner foam core of the board. Subsequent passes melt previous ones.

Second from top: 15 power, 1.0 speed, 12 passes. There is reduced melting but still some ribbing at the extents of each passes cutting.

Third from top: 10power, 1.0 speed (note after 12 passes I snapped the part out to check progress, hence bottom of it is ragged). This is the best results I'm getting. Still ribbing where the material melts but due to low power settings each melt line is smaller.

Bottom part: 100% power, 12 speed, 4 passes. Very distinct ribbing shows where each pass cuts to.

Long story short this material cuts fine on the hard surface skin but the inner core is so low density that it melts with even low power and fast speeds. will see what the client is willing to pay compared to how good they need it to be and see if the money is there to do it right. I think in the passed they have had the letters CNC's but for some reason (possibly due to how fine some of the script is CNC isn't suitable this time).

[Chuck Stone]

I just saw that they've put vinyl on it BEFORE you put it in the laser?
You'll want to be very careful with that.. vinyl and lasers don't play well together.

I think that at this thickness you're going to need to focus inside the material,
not on the surface. And being urethane foam, you're going to want that beam
moving as quickly as possible to minimize the melting. Perhaps less dpi? The more
power you can apply, the more speed you can use.

Do you have a longer lens? That might help too.

But that vinyl would worry me. It can cause problems with the metal parts in
your laser.

[Robert E Mason]

Thanks for the response.

I don't have a longer lense unfortunately but am focusing a little through the material. The vinyl is about a hairs thickness, so although it isn't ideal I'm letting it go this job, I have really good extraction also. Client agreed to pay more so am just going to do the fast speed and low power with multiple passes and have told them for future jobs this isn't an ideal method.

[Joe Pelonio]

I would have passed on the job. I have experimented with this, it's basically foam core with polystyrene instead of paper on the surfaces. If you make it work pass on the details, the best I could do was nice sharp edges on the styrene but concave edge on the foam that not only looks poor but weakens it's resistance to smashing on the edges.

[Mike Null]

I would focus well into the material and boost the pressure on your air assist.

I'm not an advocate of cutting vinyl but I do it in limited amounts with good air flow.

It would be helpful if you'd take the time to fill in your profile so we can see what equipment you have and the location.

[Robert E Mason]

Thanks for the replies.

I wish I had turned this one down too and will be telling the client this was a one off. The material is such a pain to work with there is never going to be enough money in a job to pay for itself and in this case it was only worth doing as the laser wasn't busy anyway (I'm not a laser cutting business really, but the client made me the sign for the outside of my workshop so approached me about doing this for him).

I did finally complete the job using the best case settings I mentioned in my preivous post. As well as multiple passes I focused the job at the top surface for the first cut to ensure a nice clean cut through the vinyl then moved the focus point to about 30% into the job for the remaining cuts. It wasn't amazing but it's acceptable. The sign is going 10 feet in the air above a doorway so the slight ribbing that is visible with the part in hand isn't going to be visible when installed.

[Robert E Mason]

Also, updated my profile to add info and made asig for future posts.

[Mike Null]

Robert

Thanks and good luck.

[George D Gabert]

Just a thought (have not cut this material). Could you cut this slightly oversized in 1 pass to get through material. Then cut the material fast to size. this will allow for some place for the heat to blow the materials into and away from the cutting area. Maybe even weed and then do a final trim cut to size.

GDG

[Scott Shepherd]

Just a side note, I didn't see anywhere where you mentioned the frequency you were using. What frequency did you cut with? A very low frequency might improve things. Not sure it'll solve them, but it should help.

[Robert E Mason]

The job is fine script so there isn't really rooom to do that. Problem is also that with enough power to cut through the material in 1 hit the inner core melts a lot, about 1/2" eaither side of the cut line.