sarconastic

Fix for sloppiness is Laserpoint machine.

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When I first got my machine I went over it with a fine tooth comb adjusting dialing and just basically getting it cutting as good as I could for a Chinese machine. I got it close but I still wasn't 100% satisfied, I'm kind of a perfectionist in that respect. So I was installing my blade holder and noticed a little front to back slop in the holder. What I mean is, you grab onto the blade holder bracket after you have a blade in place and lightly pull back and forth on it from front to back of the machine.

After studying the machine for a little bit I saw that on the left side of the cutter head are two roller bearings that are screwed in the head, there are spring like bars running up and down that keep these bearings in line and prevent the lower cutter head from rotating on the solenoid shaft. This may sound a little technical but it's not that hard to fix. I will post a pic when I get time to do it.

the way this works is there is a threaded screw that runs through one bearing, a nut to lock that bearing in place. then another bearing gets tightened against the nut when you tighten the screw, The first bearing on mine was little loose, allowing the cutter to slop back and forth. I  removed the screw, place a piece of paper under it, there are several tiny little washers in there.

I removed the inner bearing and the nylon washers on either side of it. Then tightened the jamb nut tight up against the outer bearing. then I put the washers and inner bearing back on, then reinstalled the whole assembly and tightened the screw back down...

Huge improvement in the corners and I got rid of most of the little pig tail it was leaving at the start of a cut. Almost all of the play I had is gone and it seems much tighter.

Hope this helps someone else with similar problems. What it does, is show that sometimes even though a machine is inexpensive a little ingenuity can make it work like a much more expensive piece of equipment.

Kevin

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Kevin, thanks for taking the time to post this tip and explain... I'm sure this will be very helpful to the other LP users.

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A picture tells more then thousand words. :thumbsup:

Paco

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,I am gonna get a picture on here, when I get some time to take it apart again. but the fact is if ya can't figure it out from the words, ya probably hadn't ought to mess with it ;-)

Kevin

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I did mesh with the head already for the laser point connection so the cover was removed already more then once and I checked for play in the part that moves up and down and carries the knife holder.!  :thumbsup:

I also have som play but do not knwo if this is inside the specs of the machine as it was from the start this way.

But I am stupid engineer so have to be told by pictures first. :thumbsup:

I wait and see what you mean by the pciture.

Regards,

Paco

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Even after I adjusted mine there is a small amount of play in the actual Solenoid shaft that I couldn't do a lot about. but tightening the bearings took out a good amount of horizontal front to back play at the knife holder. Maybe this evening I can get time to snap a pic of it and post it. I just haven't had a lot of free time here lately to mess with it.

I always think about things like pictures after I finished and the fix actually works. I used to work CNC Maintenance in a factory, and had more fun messing' with engineers on those machines, they were a good bunch of guys too.. But I never did let them know that I had a degree in Electrical Engineering too. Our running joke was if Maintenance ran out of something to do, just call an engineer and have em redesign something for us. Guaranteed work for 3 months.

Thanks

Kevin

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Nice job man.

I took mine off and tightened the nut which was pretty loose and it definitely took some of the front-to-back play out of it.  Like you, I still have some play in the solenoid and sliding shaft.

I have never had any problem with it not closing cuts, but I figured what the hell.

Thanks!

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Thanks for the fix, Kevin!

Since I'm routinely up to my elbows in computer guts or covered in parts from one of our moving lights I figured this can't be all that much different and decided to give it a look-see.

I'll start by saying "damn I'm glad I'm ambidexterous!" since you need to pretty much hold the head with your right hand and undo the screw with your left. I noticed that the jamb nut -was- lose and gave it a quick twist with screwdriver and pliers. I also noticed that I did -not- have as many washers as I thought I should have (I had three, where I think there should really be four, one for each side of each bearing). Once tightened it was a quick put-together (I don't think I could live without a #2 Philips screwdriver).

My main observation from this exercise was - yes, the jamb nuts aren't put on right at the factory - BUT that's not what I think the problem really is. Even tight, the head still has what I consider a bit too much play (.25-.5mm). The bearings do not touch both the front and back guide rails at the same time, instead riding either one or the other depending on which way the feed rollers are moving. It's a -very- small amount of play but, then, the "pigtails" on the vinyl are -very- small, also. I can't see any way to tighten the rails short of bending them (which would change them from parallel guides to angles or arcs - which is Not Good) so I'm wondering if a strip or two of vinyl adhered to the inside of one might not tighten it up a bit more while keeping them parallel.

So - I ran a quick test cut on my production company's logo (6" wide and 2.5" high, two lines of curves and swoopy text) since we can always use a few more case labels. My first observation - it weeded a LOT easier. My second observation - still has pigtails, though perhaps not as many nor as severe/large.

Conclusion - I think this is a fix that could be helpful to a number of people (and is something you should probably check anyhow) but, sadly, isn't the Magic Bullet repair many of us were hoping for to deal with the pesky problem of cuts not fully closing. Thanks again for the breakdown and photo - both definitely helped!  ;D

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Yikes. I can't see tearing mine apart. I have had similar issues with cuts completing. It seems to come and go though. It usually messes up when I really need something, but does fine when I am just messing around.

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Its not the bearings that have the play in it .It is the solenoid its self that has the play in it.After playing with this for a couple of weeks and taking the cover off and looking at it.holding the assembly and lightly moving it back and forth it plainly shows that the solenoid that moves the blade holder is what has all the play .Poorly made .I just bought this 24 laser and also bought a mh -365 and the 365 kills the 24 by no comparison .Mh-365 is not built like the 24. trying to look at all angles here ,but so far I think this 24 is nothing but problems.

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If you have play in the solenoid then you have a bad one. there is no play in my solenoid that is significantly noticeable. the bearing fix is a very common problem. I have had dozens of people on here try this fix and tell how much it improved the machine. No it won't cut like a Graphtec, but it can be made better. I have been cutting extremely detailed and fine small print with mine since I took the time to actually set the machine up correctly.

I personally would be hard pressed to believe ( From what I have read on here)  that the MH could outperform a properly setup LP. The Pcut maybe, since it's basically the same machine, sans laser.

Kevin

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HMMM... I am only going by what I see .I take all advice from everyone here and have tried the bearing thing as well.And yes their is play in the solenoid .So I am assuming from you say this is bad? This was only from my personal experience with both machines as of now.I grab the assembly on the mh and have no movement what so ever .Grab the assembly on the laser and it is terrible.When I last posted this laser cutter was two weeks old.If this is the case that it is bad and have read that their are bad parts and missing screws and what else not on these machines .The manufacturer is terrible and they need to shut down .Who wants to deal with buying a new piece of equipment and it is a piece of junk.Granite it is a cheaper unit but that is no excuse for this kind of nonsense.Good customer service -yes but what do you tell someone when they ask you -hey how is that new cutter you got from US cutter ?I do not bad mouth anyone ever so what Am I and others suppose to do ? get stuck with a piece of recycled junk? For what it is I am happy with it,but Do not understand why a so called new piece of equipment is so beat.For the record here I am not bad mouthing anyone or pointing the finger at anyone .Defective parts -yes this occurs but it seems like it happens way to much with these units.

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I cut thick media as much as thin.

If you think this is an issue with thin media you should try thicker media.

Thicker media causes more strain on entire blade holder assembly.

So running across sarconastic post I was all ears.

I took the cover off and followed along step by step.  When I went to tighten down the nut I noticed mine was already very nice and tight. I reassembled everything and checked for the slop in the back and forward motion.

Every bit of it was still there. So I looked a little harder at where all the slop was coming from and though I did notice the support bar on the right that's connected to the solenoid had a little play in the sleeve the bulk of the slop was coming from the bearing area on the left. After looking behind the left little bracket that the left bearing ride on and has the ground wire mounted to it, I noticed the problem.

Behind this bracket there is a small thin metal strip. I assume it is to act like a shock absorber for the blade bracket.

But found it to be more useful for slop than anything else and really is not needed IMO.

If you look at the bracket from the side profile you will see it has a dip bent into the bracket then the thin strip bridges over the gap. This gap allows the thin metal strip to flex into the dip when the bearing push against it.  This is where I was getting all my slop.

I simply took the little bracket with the ground wire off and hammered it flat, then made SURE it was perfectly flat and straight by laying it on glass.  Even though I hammered it flat to take the dip out there still was a small little tiny dips from the bend lines on the bracket. These need to be filled in other wise the bearing will roll over these dips and just causes the lifting and lowering to not be as smooth as I prefer.

I also noticed that even though when installed it looks as though the rolling face of the bearing is dead in line with the mounting plate of the bracket, so you would think by having a great flat bracket now the bearing would touch and ride the bracket but there is still a little small gap.

What I did here was place the thin strip back in like it was before with the now flattened metal bracket and though it does not seem to make much sense it filled the gap perfectly.

Now when I move the head forward and back the slop (what very very little is left) is from the solenoid support shaft and its coupling on the right.

I will post pics soon if it would better help to understand what I am talking about here.

Bottom Line

Now that the left bearing is rolling against a more solid surface it does transfer a little more noise from the up and down motion of the blade holder but I am very happy with the outcome and it's greatly fixed my slop and gap issues.

Eric

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db, I'd really love it if you posted a few pictures about this fix. - Thanx!

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Check blade offset if using SB program it’s under: file, cutter, setup, blade offset. On a 45 deg blade us cutter tells you .24, I had to go to .35 the previous blade .22 was needed. Also behind the left little bracket that the left bearing rides on has a small thin BI metal “spring steel" strip. It keeps tension on the bearings for alignment for the blade and prevents binding.

mine had gotten slightly bent out to determined this just remove and lay it on a flat surface holding finger tips on the part where the screws hold it down the end should be touching the surface as well, also flex the spring steel to give it a little more bend ..Make sure it’s a smooth curve avoid bending it in such a way that its makes sudden bends remember the bearing needs to roll smoothly right! Be sure not to over do it. Another thing to check is the spring rollers. make sure they are working properly no bends or cracks "the spring rollers are on top of the carriage" another thing for small decals slow down the cutting speed and re test the cutting pressure it can change with the speeds slower speeds take less pressure depending on sharpness of blade too. Watch out moding your vinyl cutter a lot of testing designing went into it! I have found out very seldom you can mod a product and get over all better performance from it you my get it to do that one thing your after but by doing it you may sacrifice dependability and more :thumbsup:

Email me

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I know I am kinda reviving this thread from the dead, but will these fixes mentioned help me get rid of the tabs that are left when I try to cut smaller lettering and such? When it cuts them it leaves small tabs that stick to the rest of the vinyl that I am trying to weed. It is so frustrating that it makes me want to buy $1k+ cutter that i cant really afford lol

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I know I am kinda reviving this thread from the dead, but will these fixes mentioned help me get rid of the tabs that are left when I try to cut smaller lettering and such? When it cuts them it leaves small tabs that stick to the rest of the vinyl that I am trying to weed. It is so frustrating that it makes me want to buy $1k+ cutter that i cant really afford lol

if using flexi or scalp add to the overcut in the cutting section of the program so it cuts a little past the end

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There is always a lot to consider. Every machine is different, and some are more capable than others. While 180 IPM is neither realistic nor really slow, it is more a matter of how the whole machine can handle the velocity.

The CMT cutter is excellent, I have that same cutter.

The speed and feed calculate to .004 chip load on a 3 flute cutter. That is good, but then the issues become:

1) Can the chips move out of the cutter fast enough? With a pointy cutter like you have the flute gullet at the tip is very very small, while at the top large. Still, tongue in cheek I say, sure, that's ok.

2) With "V"- grooving, the machine is making extremely rapid changes in axis directions. That is a large amount of weight changing direction very very quickly. Is the machine rigid enough and powerful enough to overcome the forces in the changing directions? Again, tongue in cheek - errr - maybe not.


So, With chip load in mind and the machine rigidity in mind, and the changing direction in mind - I will recommend trying this:

90 IPM, 8000 RPM, this stays with a .004 chip load.
You could change only feed rate to 75 IPM and still have a chip load of .003 which is OK.

If this does not work, then I would suggest looking into how tight the bolts are, adjusting the linear slides, generally tightening up the machine.

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