When I need a bit of MDF I use a clipboard from the dollar store. Cut (or break) off the spring-loaded clamp, and it makes for a reasonably nice piece of wood to work with.
Dang it, I thought I was the only one who thought about dollar-store clipboards. My girls love going there, and I've been surprised at what I've found there. Sometimes I make solo trips there (so as to not be distracted by my cuties) just to wander through and make mental notes about items which could be repurposed for robot materials and a (hopefully) universal parts source around the country. I had two favorites disappear just in the last month or so. Universal IR remotes and packages of 12" wooden dowel rods in varying diameters and colors. I would have used both of them in my upcoming robotics class, DOH! In a related story, I see those $1 remotes being sold for $2-3 at the TRW swap meet!
More specifically, I am eyeing the dollar store clipboard as a cheap platform to build a robot arm printer on. Retain the clipboard function to hold paper down as an arm writes on it, as my BS2 printer did at https://www.youtube.com/watch?t=20&v=5-Z56kPpcM4
Hmmm, Gordon, that sounds like another book-worthy chapter!
When I need a bit of MDF I use a clipboard from the dollar store. Cut (or break) off the spring-loaded clamp, and it makes for a reasonably nice piece of wood to work with.
The clipboard material I have seen is more like tempered hardboard (masonite), quite a bit different from the HD MDF.
The clipboard material I have seen is more like tempered hardboard (masonite), quite a bit different from the HD MDF.
True, "MDF" covers a lot of ground. By it's nature, most of the clipboard backings I've seen are fairly similar to Masonite, which is a high density fiberboard/hardboard. When you get to the smaller thicknesses, true M(edium)DF can be too flaky. At least that's been my experience. When you mentioned 1/8" MDF, I assumed you were referred to something more like Masonite or other hardboard. I think the thinnest MDF I've seen is 1/4", and even that can be fairly weak.
There's also printed laminates at the flooring store. pretty cheap by the square foot. (When I need just a small piece, I raid the flooring samples at Home Depot and Lowe's. Cut off the tongue and grooving, and there you go.)
Would love to see 1/8" MDF, but never have. We cut tons of 1/4" MDF on our laser for all sorts of jigs, fixtures, etc. My industrial engineer models up designs in AutoCAD and prints them straight to the laser using kerf offsets based on the cut width of the laser beam. Very nice fits of dovetail and other types of joints. I envy his CAD skills often as he consistently shows how much "3D work" can be done with a "2D laser".
It's a beauty to behold, that's for sure. But I wonder if the material is called MDF out of tradition, but is actually closer in density to a hardboard. Most of the traditional MDFs, at 1/8", would be fairly brittle.
If you still have a receipt for the material you previously bought, maybe it has a UPC on it, and we could look up its manufacturer. According to this page, Georgia Pacific sells it down to 1/10" inch, and they call it "thin MDF." Whether it's density matches that of the thicker MDFs isn't noted on the page (maybe the density is shown in the PDF spec, which I didn't download).
Not sure if I still have a UPC code. Good news is that I may have found a new source. Edensaw in Port Townsend is sending me a few sheets. Sounds like the same stuff or very similar to what I was using before. I'll know in a few days.
MDF just might indicate 'medium density fiberboard' as there is plywood with an MDO covering where MDO means Medium Density Overlay. MDO plywood is used for furnature and signs ... where one doesn't want any grain to show.
You piqued my interest, so I ran out to Edensaw to look at the MDF. I've never used it, but it looks like interesting stuff. At $7.00, it's half the price of the .110" Meranti doorskin I've been making things from. However, the tag on the MDF warned that it contains formaldehyde. 'Not sure what the consequences of that are for laser cutting, but at least it's not a chlorine compound (CH₂O).
(Somehow, I managed to get out of Edensaw with as much money as I went in with -- a rare occurrence.)
I know one can get finer detail with a laser cutter but for thin MDF (or whatever it turns out to be) and plywood does laser cutting offer an advantage over routing if a router can handle the detail desired?
I imagine laser cut plywood would have cleaner (smoother) edge than plywood cut with a router. Is this the case? I'd think there would be times when a router would be preferred over a laser cutter since laser cutting leaves a charred edge.
I imagine laser cut plywood would have cleaner (smoother) edge than plywood cut with a router. Is this the case? I'd think there would be times when a router would be preferred over a laser cutter since laser cutting leaves a charred edge.
I don't do laser cutting but given the proper mill end, plywood cut on a router will be smooth as a baby's bottom. Sand the surfaces of the sheet first, and when the parts come out of the router they will not require any further work. Certainly no cleaning of the char.
The disadvantage is that the smallest hole/line/radius is limited to the diameter of the mill end. So fine filigree is out.
I am concerned about the formaldehyde in that MDF. It would imagine it would only be dangerous to living creatures, and not damage your equipment due to acid rain. I'd make sure the ventilators are on high, though. But that's just me...
The laser does not always char the edges, it depends upon the material. Sometimes it makes a black charred edge that will turn your fingers black, other times you can run a paper towel along the edge and it stays clean.
One huge advantage of a laser cutter over a router is that inside corner cuts can be square without any filleting. Also, because the "kerf" of a laser cutter is only about 0.005", you waste less material. In addition, there's no dust collection to worry about -- only venting -- and the machine is very quiet with no 20000 rpm whine. Finally, engraving can be as fine as 1000 dpi, and you can even do halftones (i.e. photos).
The main advantages of a router are that you can cut thicker material and do 3D cuts. Plus, you can get a router that will handle a 4x8 sheet of plywood. I've never seen a laser cutter that big.
You piqued my interest, so I ran out to Edensaw to look at the MDF. I've never used it, but it looks like interesting stuff. At $7.00, it's half the price of the .110" Meranti doorskin I've been making things from. However, the tag on the MDF warned that it contains formaldehyde. 'Not sure what the consequences of that are for laser cutting, but at least it's not a chlorine compound (CH₂O).
So did it look similar to the picture of the case that I posted? At $7 a sheet it is less than half the price of the Home Depot stuff I was using. The downside is that I'll have to cut it into 24" x 48" pieces myself.
My understanding is that formaldehyde is not harmful to the machine, but you want to make sure not to breathe the fumes.
Plus, you can get a router that will handle a 4x8 sheet of plywood. I've never seen a laser cutter that big.
Lots of lasers are that big, and bigger. Of course they are very expensive, but you could probably get a Chinese one for $12k or so. Look at Kern for US made flatbed lasers.
You forgot the other big advantage of laser cutting - not having to hold down the material.
The laser does not always char the edges, it depends upon the material. ...
... and upon the settings you're using. The ideal edge is one with caramelized -- not burnt -- resins. Think of a steak on the grill: you can get it nice and brown, or you can burn it to a crisp.
Materials that laser cleanly:
wood
paper
cardboard
acrylic (Plexiglas)
acetal (Delrin)
Materials that cut okay but leave an ash:
leather
cork
epoxy/glass
paper/phenolic (Formica)
mica (white powder on edges instead of black ash)
'Had an interesting occurrence in class today. There was a scrap of unidentified 1/4" plastic that a student wanted to cut on the laser. So we did the copper/torch chlorine test (Thanks, Rich!) on it and determined that it was safe to cut. It cut very cleanly, which prompted me to state that it must have been acrylic. But the student grabbed the leftover scrap, which had a thin "hinge" waving in the air without snapping. Acrylic is too brittle for that to have been the case. So it might have been ABS. But my experience with ABS is that it does not laser cleanly. So I'm mystified.
There is also a material called "impact-modified acrylic" that's much less brittle than regular acrylic. You can get it in very thin sheets. It's handy for windows in model boats and planes, for example. The class tried using it to make weed-proof screens for the floating-ROV thrusters. They held up pretty well, but eventually broke apart. 1/32" acetal turned out to be the more robust choice.
Finally, regarding plywood: sometimes the inner plies contain filler (think Bondo). Those areas will not cut through with a laser. I've had this happen with the cheap doorskin I buy from Edensaw. Fortunately, it's not all that common.
You forgot the other big advantage of laser cutting - not having to hold down the material.
Oh, right! That's HUGE! -- unless the material is warped. Then I use either lead weights or masking tape along the edges.
Lots of lasers are that big, and bigger. Of course they are very expensive, but you could probably get a Chinese one for $12k or so.
After the research I've done, I'd rather spend the bucks for a U.S.-made laser cutter with a metal laser tube. Before ordering the Epilog Zing 24 for the HS class, we talked with several maker spaces in Seattle. And, while the Chinese lasers are temptingly inexpensive, they all seemed to have issues, many surrounding their glass laser tubes. Purchasing the Zing (~$15K) is not a decision we've regretted. And it gets almost continuous use during class time.
But my experience with ABS is that it does not laser cleanly. So I'm mystified.
I used Pololu's laser cutting service a few years ago and had them cut some ABS parts. I thought the parts came out great. I have one of the small pieces sitting in front of me. I could take a picture of it if you'd like.
One side of the ABS is smooth and the other textured.
One side of the ABS is smooth and the other textured.
That's exactly what the scrap piece my students found looks like. It's also opaque black. Maybe I need to reconsider my disdain for lasering the material.
Has anyone done vacumn formed thermoplastic, and then trim the edges as required?
It seems the focus is just on box shaped enclosures so far. But as best as I can recall, one may use a regular vacumn cleaner and heat lamps on a small table made of perforated masonite (usually used for hanging tools).
All sorts of shapes can be created.
Some of these boxes are sized to just use an oven broiler as the heating element. Results are very creative and useful. I see complete chassis for a quad copter has been done as one single unit.
American plywood will use filler in voids in veneer, but there is marine grade and European plywood that is guaranteed to be without voids. Much of this is used as light weight material for the interior of airplanes and there are a few specialty suppliers listed with the airplane interior materials.
There are also exotic light weight panels with foam or honeycomb cores for airplane partitions and cabinets. Of course, they aren't cheap.
Hi
I do some vacuum forming of thermoplastics.
Mostly I use a material called PETG.
It forms well, it's clear and it trims pretty smoothly with a dremel tool.
The plastics I form start out as mostly 0.188" 3/16.
I have done odd shapes and draws up to about 10" from a 24"x24" piece of plastic.
I use a shop vac to start the vacuum process, but in order to pull some detail, I have a storage tank that I pull to about 24" mercury vacuum.
My 1st heating oven uses a heating element from an electric meat smoker.
..
To start, you need some type of oven, frame to clamp the plastic sheet, source of vacuum.
then you need to build the tool over which to stretch the heated plastic.
Rounded things form better than square things.
Most time is spent trimming away the plastic that is not the part.
If you have no method of recycling the plastic, the process is pretty wasteful of material.
..
For small parts, I usually have them 3D printed by a printing service like MakeXYZ,
I also use 1/8" MDF board when building small boxes and such.
Here's a closeup of the textured side of my piece of laser cut ABS.
Hard to determine scale, but first glance I would have suggested it was HDPE. It can have a similar patterned side. HDPE is surprisingly easy to cut on a CNC router, BTW. It's what they use for the Eddie platforms.
Depending on the size of that part, these will come out much nicer looking on a router, ABS or HDPE.
Hard to determine scale, but first glance I would have suggested it was HDPE. It can have a similar patterned side. HDPE is surprisingly easy to cut on a CNC router, BTW. It's what they use for the Eddie platforms.
Depending on the size of that part, these will come out much nicer looking on a router, ABS or HDPE.
Hard to determine scale, but first glance I would have suggested it was HDPE. It can have a similar patterned side. HDPE is surprisingly easy to cut on a CNC router, BTW. It's what they use for the Eddie platforms.
Depending on the size of that part, these will come out much nicer looking on a router, ABS or HDPE.
The ABS is 1/8" thick. I'm glad to hear it cuts well with a router. ABS is another one of those nice plastics for robotics.
I suppose ABS and HDPE look similar but, as I'm sure you know, it's pretty easy to tell ABS isn't HDPE once it's in your hand.
Comments
Dang it, I thought I was the only one who thought about dollar-store clipboards. My girls love going there, and I've been surprised at what I've found there. Sometimes I make solo trips there (so as to not be distracted by my cuties) just to wander through and make mental notes about items which could be repurposed for robot materials and a (hopefully) universal parts source around the country. I had two favorites disappear just in the last month or so. Universal IR remotes and packages of 12" wooden dowel rods in varying diameters and colors. I would have used both of them in my upcoming robotics class, DOH! In a related story, I see those $1 remotes being sold for $2-3 at the TRW swap meet!
More specifically, I am eyeing the dollar store clipboard as a cheap platform to build a robot arm printer on. Retain the clipboard function to hold paper down as an arm writes on it, as my BS2 printer did at https://www.youtube.com/watch?t=20&v=5-Z56kPpcM4
Hmmm, Gordon, that sounds like another book-worthy chapter!
The clipboard material I have seen is more like tempered hardboard (masonite), quite a bit different from the HD MDF.
True, "MDF" covers a lot of ground. By it's nature, most of the clipboard backings I've seen are fairly similar to Masonite, which is a high density fiberboard/hardboard. When you get to the smaller thicknesses, true M(edium)DF can be too flaky. At least that's been my experience. When you mentioned 1/8" MDF, I assumed you were referred to something more like Masonite or other hardboard. I think the thinnest MDF I've seen is 1/4", and even that can be fairly weak.
There's also printed laminates at the flooring store. pretty cheap by the square foot. (When I need just a small piece, I raid the flooring samples at Home Depot and Lowe's. Cut off the tongue and grooving, and there you go.)
If you still have a receipt for the material you previously bought, maybe it has a UPC on it, and we could look up its manufacturer. According to this page, Georgia Pacific sells it down to 1/10" inch, and they call it "thin MDF." Whether it's density matches that of the thicker MDFs isn't noted on the page (maybe the density is shown in the PDF spec, which I didn't download).
http://www.buildgp.com/hardboard-thin-mdf
Look here for some info; http://www.edensaw.com/MainSite/Store1/StoreProducts/ProductDetail/3660
http://en.wikipedia.org/wiki/Medium-density_fibreboard
Masonite is a brand and I believe it actually might be considered higher density, maybe a different process.
http://en.wikipedia.org/wiki/Masonite
Has anyone tried bamboo? It seems to be a material of choice where I am.
You piqued my interest, so I ran out to Edensaw to look at the MDF. I've never used it, but it looks like interesting stuff. At $7.00, it's half the price of the .110" Meranti doorskin I've been making things from. However, the tag on the MDF warned that it contains formaldehyde. 'Not sure what the consequences of that are for laser cutting, but at least it's not a chlorine compound (CH₂O).
(Somehow, I managed to get out of Edensaw with as much money as I went in with -- a rare occurrence.)
-Phil
I imagine laser cut plywood would have cleaner (smoother) edge than plywood cut with a router. Is this the case? I'd think there would be times when a router would be preferred over a laser cutter since laser cutting leaves a charred edge.
How do the two cutting methods compare?
I don't do laser cutting but given the proper mill end, plywood cut on a router will be smooth as a baby's bottom. Sand the surfaces of the sheet first, and when the parts come out of the router they will not require any further work. Certainly no cleaning of the char.
The disadvantage is that the smallest hole/line/radius is limited to the diameter of the mill end. So fine filigree is out.
I am concerned about the formaldehyde in that MDF. It would imagine it would only be dangerous to living creatures, and not damage your equipment due to acid rain. I'd make sure the ventilators are on high, though. But that's just me...
The laser does not always char the edges, it depends upon the material. Sometimes it makes a black charred edge that will turn your fingers black, other times you can run a paper towel along the edge and it stays clean.
The main advantages of a router are that you can cut thicker material and do 3D cuts. Plus, you can get a router that will handle a 4x8 sheet of plywood. I've never seen a laser cutter that big.
-Phil
So did it look similar to the picture of the case that I posted? At $7 a sheet it is less than half the price of the Home Depot stuff I was using. The downside is that I'll have to cut it into 24" x 48" pieces myself.
My understanding is that formaldehyde is not harmful to the machine, but you want to make sure not to breathe the fumes.
Lots of lasers are that big, and bigger. Of course they are very expensive, but you could probably get a Chinese one for $12k or so. Look at Kern for US made flatbed lasers.
You forgot the other big advantage of laser cutting - not having to hold down the material.
Materials that laser cleanly:
paper
cardboard
acrylic (Plexiglas)
acetal (Delrin)
Materials that cut okay but leave an ash:
cork
epoxy/glass
paper/phenolic (Formica)
mica (white powder on edges instead of black ash)
'Had an interesting occurrence in class today. There was a scrap of unidentified 1/4" plastic that a student wanted to cut on the laser. So we did the copper/torch chlorine test (Thanks, Rich!) on it and determined that it was safe to cut. It cut very cleanly, which prompted me to state that it must have been acrylic. But the student grabbed the leftover scrap, which had a thin "hinge" waving in the air without snapping. Acrylic is too brittle for that to have been the case. So it might have been ABS. But my experience with ABS is that it does not laser cleanly. So I'm mystified.
There is also a material called "impact-modified acrylic" that's much less brittle than regular acrylic. You can get it in very thin sheets. It's handy for windows in model boats and planes, for example. The class tried using it to make weed-proof screens for the floating-ROV thrusters. They held up pretty well, but eventually broke apart. 1/32" acetal turned out to be the more robust choice.
Finally, regarding plywood: sometimes the inner plies contain filler (think Bondo). Those areas will not cut through with a laser. I've had this happen with the cheap doorskin I buy from Edensaw. Fortunately, it's not all that common.
-Phil
After the research I've done, I'd rather spend the bucks for a U.S.-made laser cutter with a metal laser tube. Before ordering the Epilog Zing 24 for the HS class, we talked with several maker spaces in Seattle. And, while the Chinese lasers are temptingly inexpensive, they all seemed to have issues, many surrounding their glass laser tubes. Purchasing the Zing (~$15K) is not a decision we've regretted. And it gets almost continuous use during class time.
-Phil
I used Pololu's laser cutting service a few years ago and had them cut some ABS parts. I thought the parts came out great. I have one of the small pieces sitting in front of me. I could take a picture of it if you'd like.
One side of the ABS is smooth and the other textured.
-Phil
This is the piece flipped over.
I think you can see the kerf (I suppose it should be the angle of the kerf (which I think has its own word))in this last photo.
As you can see, the small hole cut nice and clean.
Edit: Here's a link to the ABS section of Pololu's laser cutting service.
https://www.pololu.com/docs/0J24/3#abs
My experience with Pololu's service was very positive.
-Phil
It seems the focus is just on box shaped enclosures so far. But as best as I can recall, one may use a regular vacumn cleaner and heat lamps on a small table made of perforated masonite (usually used for hanging tools).
All sorts of shapes can be created.
Some of these boxes are sized to just use an oven broiler as the heating element. Results are very creative and useful. I see complete chassis for a quad copter has been done as one single unit.
http://diydrones.com/profiles/blogs/the-flying-squirrel-an-unbreakable-diy-drone-concept
Seems to be ABS of some sort. http://www.curbellplastics.com/sign-pop/abs.html
American plywood will use filler in voids in veneer, but there is marine grade and European plywood that is guaranteed to be without voids. Much of this is used as light weight material for the interior of airplanes and there are a few specialty suppliers listed with the airplane interior materials.
There are also exotic light weight panels with foam or honeycomb cores for airplane partitions and cabinets. Of course, they aren't cheap.
http://www.honeycombpanels.eu/64/panels-for-aircraft-interiors
I do some vacuum forming of thermoplastics.
Mostly I use a material called PETG.
It forms well, it's clear and it trims pretty smoothly with a dremel tool.
The plastics I form start out as mostly 0.188" 3/16.
I have done odd shapes and draws up to about 10" from a 24"x24" piece of plastic.
I use a shop vac to start the vacuum process, but in order to pull some detail, I have a storage tank that I pull to about 24" mercury vacuum.
My 1st heating oven uses a heating element from an electric meat smoker.
..
To start, you need some type of oven, frame to clamp the plastic sheet, source of vacuum.
then you need to build the tool over which to stretch the heated plastic.
Rounded things form better than square things.
Most time is spent trimming away the plastic that is not the part.
If you have no method of recycling the plastic, the process is pretty wasteful of material.
..
For small parts, I usually have them 3D printed by a printing service like MakeXYZ,
I also use 1/8" MDF board when building small boxes and such.
gg
Hard to determine scale, but first glance I would have suggested it was HDPE. It can have a similar patterned side. HDPE is surprisingly easy to cut on a CNC router, BTW. It's what they use for the Eddie platforms.
Depending on the size of that part, these will come out much nicer looking on a router, ABS or HDPE.
HDPE would also make a better hinge material...
The ABS is 1/8" thick. I'm glad to hear it cuts well with a router. ABS is another one of those nice plastics for robotics.
I suppose ABS and HDPE look similar but, as I'm sure you know, it's pretty easy to tell ABS isn't HDPE once it's in your hand.