Home Built 40W CNC Laser
Project Overview
This was designed as a "self replicating" laser cutter engraver'. What this means, is all of the high tolerance complicated parts can be made on a laser cutter. So, once one laser cutter is done, it can help make others. All of the other parts can either be purchased or made with common home tools.
This is not a mamby pamby little diode laser than can slowly cut through a piece of thin black tape. This will cut real materials, quickly. If you want to know what it can cut, go to a Ponoko type site and check out their materials list.
This was designed to be a dirt cheap, but fully capable laser cutter. Many of the material choices were made to satisfy that goal. I am sure many people will know of better materials, but usually at a higher cost. Feel free to substitute them .Almost everything that is not an off the shelf item, can be made with a laser cutter or router. To kick start the first generation of 'self replicating lasers, I have some kits located here.
The buildlog is presented blog style (most recent entry first) if you want to go view it the other way click here... Take me to the beginning of the build
How can you contribute to the project?
- Participate in the forum.
- Suggest changes. A lot of the design comes from your input.
- Link to buildlog.net. More people + more ideas = better laser
- Donate. Help fund the cost of the web site and costs associated with this project.
Buildlog Title: Buildlog.net Open Source Laser
Builder: bdring
Member Since: 2009-11-22
Wednesday, May 5th 2010 - 10:45 PM
The timing belts for the XY assembly are MXL (0.080 pitch). They are open ended and cut to length. I suggest getting about 20 feet. That will get you all three belts, plus enough to replace one if something goes wrong or breaks. I used Stock Drive 1/4 wide p/n
A 6Z16-C025. For the pulleys, I used plastic 1/4" bore 18 tooth with metal insert and 2 flanges p/n
A 6T16-020DF2508 in all six locations. you need to verify your motor shaft size.
The Z lift is XL (0.200 pitch). For the pulleys I used plastic 5/16 bore 14 tooth with metal insert and 2 flanges p/n A
6Z_3-14DF03710 for the lead screw (qty 4). I used plastic 1/4 bore 10 tooth with metal insert and 2 flanges p/n
A 6Z 3-10DF03708...again...check your motor shaft.
Everything above is from Stock Drive.
I bought the Z belt from econobelt p/n QB-XL1032-025.
I'll put this all on the drawings soon.
Update: Information has been put on the drawings.
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Tuesday, May 4th 2010 - 3:20 AM
The new versions of the drawings have been posted on the
drawings page. This includes all the new Z lift drawings and mods to the gantry to get the motor above the extrusion. I am going to work towards the part kits next. The assembly drawings need a lot of clean up, but that should be usable anyway.
My laser will be down for at least a week while I wait for for the belt. I should be ready to start cutting after that.
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Monday, May 3rd 2010 - 11:24 PM
It attaches from the bottom with two screws. You mount it lightly, then slide the belt ends in from the side. Tighten the clamp. Then tension the belt.
I hope to post the drawings tonight. This affects a lot of drawing, some only visually.
I want to post everything at once, so there is no period where old and new are on at the same time.
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Sunday, May 2nd 2010 - 7:28 PM
Here are the mods to the gantry. The putting the motor above gives maximum clearance of the table. My previous design had to allow clearance for the motor along the left side. Now you get about 2" inches of travel. The assembly is actually easier to assembly and uses less parts. The belt is tensioned by moving the motor to the left as it is tightened.
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- Gantry - Motor End
- Gantry - Idler End
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Saturday, May 1st 2010 - 9:13 PM
I measured the belt length using a piece of wrapping paper ribbon. It measured about 113" which is right about what the CAD model said. The ribbon actually worked.
. The tricky one to thread is the one with the motor. I may move that to the front. I am sure it will be easier with a real belt that has some stiffness.
Econobelt has a 103" and a 122". I think it will be easier to to move the lead screws together, so I will go with the 103" I ordered three belts.
I wonder how they make these belts. I can't imagine they have a mold for each one.
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Saturday, May 1st 2010 - 6:05 PM
When you get to the length I need for the Z lift belt, the sizes start going in 8"-10" steps. It is tough to find the size you need. I really want to try Econobelt because the price is almost a 1/3 of Stock Drive. The Z lift lead screws don't need to go at the ends of the table, so I am going to move them closer together. This might cause an issue with the X axis motor. I thought about moving the motor to the top side of gantry. This does not change much at all and gains some usable XY range.
I am going to try this method and show the results.
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Saturday, May 1st 2010 - 1:24 PM
That is a good link. I'll post it somewhere. I also searched for the track that the Chinese lasers run on, but found nothing. There has to be an extrusion house in China making them.
The races on most bearings are hardened, so it would probably need to be ground. You can get decent bearings with no play pretty cheaply. I though a press on nylon v-wheel "tire" for a bearing might work.
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Saturday, May 1st 2010 - 3:00 AM
That would be great if you could find some.
Actually, the noise is not an issue once the cover is down. The tiny motor board fan and steppers are actually louder. The wheel are strong and ridged as hell.
The real issue is cost. They cost about $10 each. They are probably the most overpriced item on the design. I just bought some
nylon V wheels from Stock Drive, but the bearings are very loose. They might work under tension, but I am skeptical. I might try on a separate piece later.
I have looked around for rubber, plastic or nylon wheels and not found anything. I'll owe some real favors to anyone who can find a decent rubber wheel and riding surface combo. I even toyed with a press on nylon part to a standard bearing.
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Saturday, May 1st 2010 - 12:08 AM
I got sent half way across the country on unexpected business yesterday and my extrusions for the new z lift appear to be one their way to Ohio. I live in Illinois about 10 miles from where they ship the parts, but the tracking number shows them slowing going towards Ohio?
I think I will temporarily use the old extrusions so I can make sure everything fits as planned and swap in the part later.
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Wednesday, April 28th 2010 - 2:55 AM
Remind again me why I tore down a working Z axis?
Here is the aftermath of my battle to get the old Z axis out. The floor had to be cut in half inside the enclosure to get it out. Good thing I have a great built in exhaust fan
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Hopefully I will have all the parts by the weekend. I am sure I can keep myself busy cleaning up.
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Sunday, April 25th 2010 - 4:24 PM
This is the table bracket I am going to try. This will bolt to the bottom of the table. It uses a T-Nut to ride on the threaded shaft. The T-Nut fits into a special pocket on the bracket. It has a little float to accommodate slight mis-aligned or non straight shafts. It is only held together with gravity. This allows very easy leveling of the table. If you need a corner to move up or down a little, you just lift the table and rotate the nut in 1/3 turn increments.
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Note: This black Acrylic is really hard to take a picture of. It is like taking a picture of a mirror. I need to get a white light tent.
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Saturday, April 24th 2010 - 10:51 PM
I fabricated the new Z lift parts. I don't have the correct pulleys yet, so I only put together the motor corner as a test. The parts all laser cut very well. It is a lot easier than routing, because you don't have to babysit the machine as much. With routing there is always concern of a piece of scrap getting itself in trouble. There will also be a piece that rides on the lead screw that attaches to the bed. I will work on that next. I want that to be much more simple than it is now.
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- Motor Plate
I doubled up on the bearings. This might not be needed, but they are a little narrow compared to the belt. There is a washer between each bearing to make sure there is no stress between the inner and outer races.
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- Motor Plate close up
I added one more feature at the last minute that may not even be necessary. Each piece with a lead screw has a tapped hole. This can be used to support the piece against the bottom if it starts to sag. A screw can be lowered to contact the floor as an additional support point. The Acrylic is quite stiff. With eight support brackets, it probably is not necessary.
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- Extra support point.
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Friday, April 23rd 2010 - 2:57 AM
I laser cut two parts to test the clamping of the bearing. I think it will work great. I am still thrilled and amazed that the laser is accurate enough to cut a hole that can later be tapped (#6-32) without any clean-up drilling.
This is one of four upper bearing blocks.
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- Z Part Test
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Thursday, April 22nd 2010 - 9:50 PM
I refined the design to use a few less parts. The motor is mounted on one of the corners. This puts it in a nice location for shortest wiring. The lower right corner has the belt adjustment. This is just the sub assembly view. It mounts to the existing frame. Not all small hardware parts are shown yet.
I think I will laser out some parts and test it.
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Wednesday, April 21st 2010 - 10:31 PM
I am working on a new simplified Z lift design. I want to make all the parts out of the same 6mm acrylic material that everything else is made out of. I also want to support it from the frame only. This will make the bottom skin simpler. It will also be much easier to build and adjust.
My first attempt at the design is shown below. This assembly will be the same in all corners but one. One corner will have some adjustment of the idler pulley to allow the belt to be tensioned. The motor (not designed yet) will be in the back of the cabinet. This design looses a little Z travel, but increases the table X/Y size. I think this is better anyway.
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- New Z Lift Design Idea
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Friday, April 16th 2010 - 1:08 AM
I don't think I posted this trick before...
Misumi sells some extruded "slot cover" material. This is a little 'C' shaped piece that snaps into the slots.
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- Slot Cover
- cover_snap.jpg (Array KiB) Viewed 14774 times
I found that it works great to dress up or hide the wires. It snaps in anywhere so you can start and stop it right where you need it.
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- Captures/Hides Wires
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Tuesday, April 13th 2010 - 1:31 AM
I bumped the mirrors a few times while installing the cover and gas springs so I wanted to re-align the mirrors. I thought a neat low tech feature would be to have a remote laser trigger. This would allow me to trigger the laser while I am near the mirrors.
I already had a manual button on my front interface, so I just put a 1/4" mono jack connector in parallel with it. I then put a button at the end of a long cable with a mating plug.
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- Remote Trigger
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Yes....my manual power control knob is timing pulley. I did not have a real knob and the pulley fit
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Saturday, April 10th 2010 - 10:14 PM
I did some finishing on the enclosure skins. I just painted them gloss white. Before I painted the front skin, I split it into three sections. I want the middle section to be easy to remove to get occasional low access from the front.
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- Painted Enclosure
I also got thew gas springs working. They were putting too much stress on the hinge. I previously had to alternate the screws because the heads were bumping into each other when the hinge was completely closed. I got some flat head M3 x 5mm and that allowed all holes to be used without the heads interfering. It works well now.
Edit: I realized the gas springs are mounted upside down and fixed. The McMaster info page on gas springs says the fat end should be mounted above the thin end wherever possible. I think this makes the seal last longer..
- Gas Springs
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Sunday, April 4th 2010 - 8:12 PM
I finally got around to cutting the window for the cover. It looks pretty good. I didn't put all the screws in place yet, because I will be painting it. I think I might add a window to the front too. It is nice to be able to see the work at a low profile when it is cutting/engraving. I put the gas springs in too, but they are distorting the hinge a little. I think I just need to add a few extra mounting holes right near the ends of the hinge. I have some simple handles too that will go on after painting.
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Wednesday, March 31st 2010 - 12:38 AM
- V25Aspire_Final_Logo.jpg (Array KiB) Viewed 13855 times
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I have been using my
Vectric Aspire program to laser cut some parts. I made a post processor file for it. Aspire is way overkill for laser cutting, but it should work for all Vectric's other programs as well.
Cut-2D is probably a good candidate for lasering and is a decent price. You can download a semi-working version for free.
The post processor is for use with Mach3 and the E1P1/E1P0 control style. I will detail my E1P1 control method in a later post.
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Monday, March 22nd 2010 - 10:52 PM
Self ReplicationMy ultimate goal with this open source laser is to make it possible to build one with no special tools. I want all of the complicated part to be fab'able by another laser. If enough people build one, there will be an easy supply of parts.
I finally got around to cutting one of the laser's own pieces. This is the laser carriage plate. You can see the original (installed) and the new piece. I put a piece of white foam board under all the pieces to give a little contrast in the picture. I have not cleaned-up the assist hose routing since I made the new cover. I actually have some new self coiling tubing I want to try.
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Sunday, March 21st 2010 - 12:49 AM
I have had this dust blower for about 4 years. It did a lame job on my router. The shop vacuum did much better. I decided to hook it up to my laser with it located right at the wall to minimize leaks that could cause gas to re-enter the shop. It is almost ready to go. It was a lot of work to plumb in and get it out the side of the house. I got ride of the bag and all the other attachments.
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Wednesday, March 17th 2010 - 4:01 PM
I found a good gas spring at McMaster Carr. The gas springs are McMaster p/n 4138T551. I did some graphical calculations on using it. As I understand it, I want to fully extend the spring at my full open which is going to be about 80deg. I want it to almost fully compress as it closes, but I want the spring to have some over-travel so the last few inches actually push it closed rather than pushing it open.
The spring is available in a lot of strengths, but I will go for the lowest, I really only want a minor amount of assist and enough to hold it open. Any extra is just unwanted stress on the enclosure.
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- Click to enlarge
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Wednesday, March 17th 2010 - 12:38 PM
I built the cover out of the framing material and temporarily put it in place without the skins. I think it will work. I think I will put two small gas springs to hold it open and closed. I think one gas spring would eventually warp the cover. I need to get some more plywood and the windows is due later this week.
I might also hinge the lower front or at least make it a quick release.
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- Cover testing
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Tuesday, March 16th 2010 - 4:27 PM
Here is more on the proposed cover. The cover has a frame that is 2020 extrusion. The cover frame fits inside the enclosure frame, but the skins for the cover are the full width of the enclosure. This will hide any gaps and seal a little better. I have the skins made out of plywood with an Acrylic window, but the whole top skin could be Acrylic.
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Sunday, March 14th 2010 - 4:26 PM
I finished aligning the laser. It is accurate to a few thousands of an inch. See this
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I started working on a cover. I originally thought a door the size of the work area would be good, But I think the reason I have held off on the cover is that I like to have full access from the top. So I have a full cover concept going. If anyone has any input, let me know. I will probably start cutting the pieces soon.
- Cover Concept
It is basically a L shaped extrusion assembly that will be skinned in plywood with a transparent window above the work area (not shown yet). I found some really cheap piano hinge that works pretty well with the extrusion. Below are some pictures of a mock-up. I have two scraps of plywood shown. One piece will actually be more like a optional decorative trim strip on the stationary side of the hinge. I plan to put at least one gas spring to hold it open.
- Hinge View
- Another view of the hinge
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Yes, Econobelt is way cheaper than stock drive, at least for the belt. Unfortunately the belt needed is not in stock. No word on shipment yet. I am tempted to try it without the fold back bearings in the corners. I think it will work and will be simpler, cheaper... What do you think. Look at the top of a Makerbot.
Kits will start when laser is back on line.
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