Thanks for the video. Nice and concise! I'm guessing you don't run a separate last pass to clean up the run out lines? I use hard Maple 18mm - 40mm thick and they can be quite hard to sand out, especially in intricate pieces. My last passes (0.1mm) often end with a broken bit when the force breaks the tabs (7mmx7mm ramps) and the piece get wedged.
Thanks for the video and insight. Starting to see these 28 gauge pin nailers at hardware stores. Curious if you have any experience with those and if they can be of any benefit for CNC work holding.
I love your channel. Just watched about 15 of your videos in a row. Just waiting for my CNC router to arrive to put all that new knowledge to good use :-) Thanks for sharing!
Another excellent video filled with great information, Peter! Thanks very much for sharing it! Learning when and where to put holding tabs is all a part of the process. I can confirm that larger cutters aren't a good choice for this method. I use 1/4 inch diameter downcut bits regularly, and the vast majority of the time, the dust collection system removes such a large portion of the chips/dust, there's just not enough left to hold the parts in place. Even without the dust collector running, the gap that 1/4 inch bit makes is so large, the chips don't pack in behind the bit firmly enough to hold the part in place. I don't know that there's a "one-size-fits-all" solution. I think that doing as you said near the beginning (evaluating the cut, material, and cutter, then applying the appropriate method as you see fit,) is the preferable way to go. That may entail using multiple methods on the same piece of material, or it may not. On larger panels that contain small parts, I may use the masking tape and CA glue method, plus clamps, or even just screw the material to the spoilboard. The tape and glue is there to hold the small parts down, while the clamps/screws hold the material. Oh, and I agree - building and using a vacuum table or vacuum pod would make a great video! I'm thinking about making a pod or two myself - eventually.
Thanks Mark, So many options to hold the work down and I am yet to tryout your tape and glue method. I must get onto that. I do have a vacuum table planned for an upcoming video but I don't see it happening before christmas. Cheers Peter
I have cut using a trick that I have done with air brushing. I use a can of 3m spray mount. What I did was place a board outside and spray it with the spray mount. Roughly about 4 coats and then place it in the machine and press down the work piece. Then clamp the board that I sprayed. Then I would proceed to cut and all those small pieces will not even move. You will have to make sure that the spray mount you use will work as some loose the stickiness and then your pieces will float. So you will not need a chopstick or a vacuum table for wood. The vacuum table if you decide to work on it, the spray mount will get you by till you have it made. ;)
Hi Rick, I posted links to the cutters in the article for this video. Under my videos is a link to the appropiate article for each video. At the bottom of the article i put links to the cutters and where I got them from. There is another link on the page with other possible suppliers and cutter types as well and you may find them cheaper. This is the one I purchsed from. ebay.to/2xienoR
Hi Peter thanks for the tips. How well does hard wood like oak and cherry and mahogany Work without tabs? Looks good with ply and mdf. How far past the stock is the cutter blade past the bottom? Thanks Jerry
Hi Jerry, I have no idea about those woods but I see no reason that it wouldn't wory. The cutter doesn't go past the bottom of the board. It cuts level with the bottom or else it would cut up the spoilboard. Cheers Peter th-cam.com/video/Q-Q1o16Ux-I/w-d-xo.html
Peter, I mostly cut solid wood, typically walnut. How do you think this might work in my situation? I've been using tape and super glue. Thanks for all the great videos.
also is there a concern of the dust over heating the cutter? i was under the impression it is best to evacuate the chips to prevent rubbing. Thanks again
That is a consideration and a balance between too much and not enough chip in the slot. My dust collection removes about 1/4" or so of chip leaving the last 1/4" for holding. The characteristic of the cutter is not changed so it was always going to behave like it does. I am just taking advantage of it's bahaviour. On thicher material 3/4" I have been guilty of using a vacuum to manually follow behind and clean out the slot until the last 1/4" and then let it fill the slot on the last few passes. Cheers Peter
Another great video Peter. I usually use 6mm endmills for cutting out material but after watching your train project I have ordered some 1/8" bits to try. What feedrate do you use
Great video Peter. You mentioned that your cutter was 3 months old. DId you sharpen it within that time frame? It's amazing if you get that much time on a single sharpening.
I mostly use a 1/8th inch upcut bit for cutting out and pretty much never use tabs, the sawdust holds them in just fine 99% of the time. That is only on 18mm thick material though when cutting thin stuff tabs or a stick to hold it down.
In my experience there are 2 more points where you can use this method (even with up-cutting endmills): - if you use real small diameter tools (I often use 1 - 2 mm) - if you don't use dust collection (better for small bits), because the saw mill will kind of clamp the parts.
Thanks ZenziWeren. I haven't had much luck with very small bits in the past. I'm probably far to rough with them. PS. I like your website site. I've been looking at a couple of your projects with a view to making a couple of them. Cheers Peter
You may have read, that I am using a quite small machine. So my feeds and depth per pass might be in another league. Further more I love to sit and watch my tiny "Zenzi" cutting :) Thanks for your nice words. I just can give them back as I really enjoy watching you videos. Lot to learn in things cnc ... If you built one of my projects I'd really love to see results. That is actually a great part of the fun that keeps me publishing the plans.
I saw on the videos that it was small but I didn't realize that it was called a Zenzi. Now I understand the channel name. Even more embarassingly, I now realize your name isn't Zenzi😊 I will video the project. Cheers Peter
Hahaha, nope, Zenzi is just kind of a funny made-up name for "c-n-c" transferred to the abbreviation for the old Bavarian girls name "Kreszentia". No reason to be embarrassed about ... I suppose I am making some strange mistakes while trying to get my School-English going ...
Often I use the "onion skin" approach... Just set the depth of a through cut say 30 thou short of completely through. Then its just a simple mater to punch out the parts by hand. the bit of wood left is easy to get rid of by basically light sanding by hand. No big deal as upcuts always leave some fuzz anyway.. I often use 3/4 and 1 inch router buts for hogging out a LOT of material and follow the profile ( inside or outside) with a 1/4 end mill to deal with what the 3/4 inch bit cant get at. Saves a lot of time even when tool changes are considered too.
+John Ware Another tried and true technique. I found that it worked best for me on mdf. The only thing I had to remember was to remove the part by pushing it through to the back or it would destroy the rear surface of the part. Cheers Peter
Not sure if we're talking about the same thing, but you can also onion-skin with the larger cutter and cut out with the smaller. The small cutter will not jam when the part shifts as it cuts out. There may be an issue if there is excessive material left in the corners due to an overly large difference in cutter diameters but, if you're careful about where the cut begins and ends, those corners can become 'tabs' of a sort in the onion-skin. Just make sure to end the cut between those. With the smaller cutter it becomes possible to 'arc on and off' at the beginning and end so as not to be cutting the part as it separates. I leave a few thousandths on the profile with the larger cutter for the smaller to clean up.
That's an interesting idea and one I hadn't thought of. For me the onion skin needed to be cut with a knife at the end of the machining and then either sanded ot a flushtrim bit to clean it up. If you get it just right it can be paper thin and need vert little encouragement at all to be got rid of. The idea of cutting with a bigger bit then finishingwith the smaller never occurred to me. I will have to bear it in mind. Cheers Peter
Another very useful video Peter, my only question is, do you mean 10 operations to cut the wheel out or 10 toolpaths? or does the term 10 toolpaths = 10 operations and I am your cnc nut job :-)Cheers Bernie
I call each individual cutout a toolpath. ie it is a separate path that the tool has to cut. That said it is all created in VCarve Pro using a single toolpath which in CamBam they call a Machining operation or MOP for short. Cheers Peter
Thanks as always for the great content! what i tend to do for really small parts that i am worried may break the cutter is just to pocket machine them instead of profile cutting. it adds a little more machining time but i know its all dust not a solid bit
I thought of that as well because then there is nothing but chips but in the train project it might be a bit much. It used to be my standard trick in VCarve Pro before they included the click to delete pieces from the pictures of the completed cuts. To be honest I have neer broken a cutter doing this but there is always a first time for everything. Cheers Peter
7 ปีที่แล้ว
I've destroyed a few cutters by getting them pinched between the loose piece and the material. Small cutters (3mm or smaller) break fairly easily. Bigger ones, like the 6mm, are really difficult to break when cutting wood, but if it gets pinched, it will burn the wood and overheat, losing heat treatment and becoming dull. When it comes to small holes, I often pocket machine them, too. Yes, it takes a bit longer and uses up the cutter a bit more, but it saves the time, effort and sandpaper needed to remove tabs in tight holes.
Right between the left handed hammers and the snake oil. 😉
7 ปีที่แล้ว
It can certainly be done with an up-cutting endmill, too, I've done it many times. I've never used a down-cutting bit. I should perhaps get a few of those, as they seem much better for this. I think that with these small cutters (say, up to 1/4" or 6 mm), it is impossible for a piece to get flung out of the machine with enough momentum that it is dangerous (of course, a CNC router is an industrial machine and there is always risk involved, don't take advice from random people say on the internet, especially if you're worried about safety). What usually goes wrong is that the cutter gets pinched between the loose piece and the surrounding material and that destroys the piece (often in a fairly spectacular fashion, with plenty of smoke and loud noises) and it sometimes breaks the cutter or burns it so that it loses heat treatment and is instantly dulled. I sometimes use lead weights as gravity clamps to hold large and medium sized pieces, and that usually works very well (just don't forget clearance on the z-axis, haha). It also helps to flatten plywood.
+Krešimir Cindrić I've never tried doing it with an up cutting bit before. I've never thought of using weights as a hold down either. That's a really interesting idea. Cheers Peter
Peter, great video and tip. I have left off tabs from parts before by accident and noticed the same behaviour. Nice to know it wasn't just a fluke. Joe
Thanks for the video. Nice and concise! I'm guessing you don't run a separate last pass to clean up the run out lines? I use hard Maple 18mm - 40mm thick and they can be quite hard to sand out, especially in intricate pieces. My last passes (0.1mm) often end with a broken bit when the force breaks the tabs (7mmx7mm ramps) and the piece get wedged.
Love your sense of humour. Thanks!
Thanks for the video and insight. Starting to see these 28 gauge pin nailers at hardware stores. Curious if you have any experience with those and if they can be of any benefit for CNC work holding.
I love your channel. Just watched about 15 of your videos in a row.
Just waiting for my CNC router to arrive to put all that new knowledge to good use :-)
Thanks for sharing!
+heriberthuber54
Thanks.
You are in for an adventure.
Cheers
Peter
Oh dear!
I kinda was hoping more for something in the piece of cake league....
+heriberthuber54
Where's the fun in that?
true :-)
Another excellent video filled with great information, Peter! Thanks very much for sharing it!
Learning when and where to put holding tabs is all a part of the process. I can confirm that larger cutters aren't a good choice for this method. I use 1/4 inch diameter downcut bits regularly, and the vast majority of the time, the dust collection system removes such a large portion of the chips/dust, there's just not enough left to hold the parts in place. Even without the dust collector running, the gap that 1/4 inch bit makes is so large, the chips don't pack in behind the bit firmly enough to hold the part in place.
I don't know that there's a "one-size-fits-all" solution. I think that doing as you said near the beginning (evaluating the cut, material, and cutter, then applying the appropriate method as you see fit,) is the preferable way to go. That may entail using multiple methods on the same piece of material, or it may not. On larger panels that contain small parts, I may use the masking tape and CA glue method, plus clamps, or even just screw the material to the spoilboard. The tape and glue is there to hold the small parts down, while the clamps/screws hold the material.
Oh, and I agree - building and using a vacuum table or vacuum pod would make a great video! I'm thinking about making a pod or two myself - eventually.
Thanks Mark,
So many options to hold the work down and I am yet to tryout your tape and glue method. I must get onto that.
I do have a vacuum table planned for an upcoming video but I don't see it happening before christmas.
Cheers
Peter
instablaster
I have cut using a trick that I have done with air brushing. I use a can of 3m spray mount. What I did was place a board outside and spray it with the spray mount. Roughly about 4 coats and then place it in the machine and press down the work piece. Then clamp the board that I sprayed. Then I would proceed to cut and all those small pieces will not even move. You will have to make sure that the spray mount you use will work as some loose the stickiness and then your pieces will float. So you will not need a chopstick or a vacuum table for wood. The vacuum table if you decide to work on it, the spray mount will get you by till you have it made. ;)
+Steven Cook
Thanks Steven.
Peter, where did you find the 1/8 in downcutting bit? I have look and can't seem to find one. Thanks
Hi Rick,
I posted links to the cutters in the article for this video.
Under my videos is a link to the appropiate article for each video.
At the bottom of the article i put links to the cutters and where I got them from.
There is another link on the page with other possible suppliers and cutter types as well and you may find them cheaper.
This is the one I purchsed from.
ebay.to/2xienoR
Hi Peter thanks for the tips. How well does hard wood like oak and cherry and mahogany Work without tabs? Looks good with ply and mdf. How far past the stock is the cutter blade past the bottom? Thanks Jerry
Hi Jerry,
I have no idea about those woods but I see no reason that it wouldn't wory.
The cutter doesn't go past the bottom of the board. It cuts level with the bottom or else it would cut up the spoilboard.
Cheers
Peter
th-cam.com/video/Q-Q1o16Ux-I/w-d-xo.html
Have you heard of the painters tape / superglue combo?
Peter, I mostly cut solid wood, typically walnut. How do you think this might work in my situation? I've been using tape and super glue. Thanks for all the great videos.
You would need to try it but I think it will work for you.
Cheers
Peter
also is there a concern of the dust over heating the cutter? i was under the impression it is best to evacuate the chips to prevent rubbing. Thanks again
That is a consideration and a balance between too much and not enough chip in the slot. My dust collection removes about 1/4" or so of chip leaving the last 1/4" for holding. The characteristic of the cutter is not changed so it was always going to behave like it does. I am just taking advantage of it's bahaviour. On thicher material 3/4" I have been guilty of using a vacuum to manually follow behind and clean out the slot until the last 1/4" and then let it fill the slot on the last few passes.
Cheers
Peter
Another great video Peter. I usually use 6mm endmills for cutting out material but after watching your train project I have ordered some 1/8" bits to try. What feedrate do you use
I started off at 50ipm and increased it's feedrate from there until i was happy with the results.
Cheers
Peter
ok thanks Peter
Forgot to mention that the spindle speed was 10000rpm
Peter- good instruction and lessons learned. Thank you. I find each of your vids to be value added.
Thanks Mocarver
Thanks Peter for another informative video. What font did you use on the mdf and ply?
Now your getting really technical. It's called Cooper Black and should be a standard windows font.
It does look nice.
cheers
Peter
Thanks Peter. I"m designing a shop sign and after seeing your video that font is what I'm going to use.
Great video Peter. You mentioned that your cutter was 3 months old. DId you sharpen it within that time frame? It's amazing if you get that much time on a single sharpening.
+rchavez 505
No I didn't sharpen it but it don't use it continuously either. It is just 1 of the tools I use as needed.
Cheers
Peter
CNCnutz (Peter Passuello) How many bits did you go through to cut the train? Did you use 1/8 for all of the cutting?
+rchavez 505
I used the old cutter for just over 3/4 of the Train before I cottoned on and changed it.
+rchavez 505
I only used a 1/8 bit for the entire cut and had I put a new one in at the start I would have only used a Single cutter.
CNCnutz (Peter Passuello) Wow that's pretty good. Great job on the train.
I mostly use a 1/8th inch upcut bit for cutting out and pretty much never use tabs, the sawdust holds them in just fine 99% of the time. That is only on 18mm thick material though when cutting thin stuff tabs or a stick to hold it down.
Thanks Den
It is good to know that others use similar methods and that a 1/8' upcut can work in the thicker material.
Cheers
Peter
Thanks for another great video Peter.
+Bruce Fleury
Thanks Bruce.
In my experience there are 2 more points where you can use this method (even with up-cutting endmills):
- if you use real small diameter tools (I often use 1 - 2 mm)
- if you don't use dust collection (better for small bits), because the saw mill will kind of clamp the parts.
Thanks ZenziWeren.
I haven't had much luck with very small bits in the past. I'm probably far to rough with them.
PS. I like your website site.
I've been looking at a couple of your projects with a view to making a couple of them.
Cheers
Peter
You may have read, that I am using a quite small machine. So my feeds and depth per pass might be in another league. Further more I love to sit and watch my tiny "Zenzi" cutting :)
Thanks for your nice words. I just can give them back as I really enjoy watching you videos. Lot to learn in things cnc ...
If you built one of my projects I'd really love to see results. That is actually a great part of the fun that keeps me publishing the plans.
I saw on the videos that it was small but I didn't realize that it was called a Zenzi.
Now I understand the channel name. Even more embarassingly, I now realize your name isn't Zenzi😊
I will video the project.
Cheers
Peter
Hahaha, nope, Zenzi is just kind of a funny made-up name for "c-n-c" transferred to the abbreviation for the old Bavarian girls name "Kreszentia".
No reason to be embarrassed about ... I suppose I am making some strange mistakes while trying to get my School-English going ...
Thanks for another great video Peter.(Next vacuum table great)
Thanks MTD
A vacuum table is on the list, but I'm not holding out much hope for this year.
Cheers
Peter
Which font did you use for the "MDF" letters? Thanks
I'm sorry Leba I can't remember and I didn't keep the file.
Cheers
Peter
Seems like Cooper to me.
I think you're right Dimitris, thank you
Often I use the "onion skin" approach... Just set the depth of a through cut say 30 thou short of completely through. Then its just a simple mater to punch out the parts by hand. the bit of wood left is easy to get rid of by basically light sanding by hand. No big deal as upcuts always leave some fuzz anyway..
I often use 3/4 and 1 inch router buts for hogging out a LOT of material and follow the profile ( inside or outside) with a 1/4 end mill to deal with what the 3/4 inch bit cant get at. Saves a lot of time even when tool changes are considered too.
+John Ware
Another tried and true technique. I found that it worked best for me on mdf. The only thing I had to remember was to remove the part by pushing it through to the back or it would destroy the rear surface of the part.
Cheers
Peter
Not sure if we're talking about the same thing, but you can also onion-skin with the larger cutter and cut out with the smaller. The small cutter will not jam when the part shifts as it cuts out. There may be an issue if there is excessive material left in the corners due to an overly large difference in cutter diameters but, if you're careful about where the cut begins and ends, those corners can become 'tabs' of a sort in the onion-skin. Just make sure to end the cut between those. With the smaller cutter it becomes possible to 'arc on and off' at the beginning and end so as not to be cutting the part as it separates.
I leave a few thousandths on the profile with the larger cutter for the smaller to clean up.
That's an interesting idea and one I hadn't thought of. For me the onion skin needed to be cut with a knife at the end of the machining and then either sanded ot a flushtrim bit to clean it up. If you get it just right it can be paper thin and need vert little encouragement at all to be got rid of. The idea of cutting with a bigger bit then finishingwith the smaller never occurred to me. I will have to bear it in mind.
Cheers
Peter
Another very useful video Peter, my only question is, do you mean 10 operations to cut the wheel out or 10 toolpaths? or does the term 10 toolpaths = 10 operations and I am your cnc nut job :-)Cheers Bernie
I call each individual cutout a toolpath. ie it is a separate path that the tool has to cut.
That said it is all created in VCarve Pro using a single toolpath which in CamBam they call a Machining operation or MOP for short.
Cheers
Peter
makes sense now as i use vcarve and counted it as 1 toolpath, thanks
Thanks as always for the great content!
what i tend to do for really small parts that i am worried may break the cutter is just to pocket machine them instead of profile cutting. it adds a little more machining time but i know its all dust not a solid bit
I thought of that as well because then there is nothing but chips but in the train project it might be a bit much.
It used to be my standard trick in VCarve Pro before they included the click to delete pieces from the pictures of the completed cuts. To be honest I have neer broken a cutter doing this but there is always a first time for everything.
Cheers
Peter
I've destroyed a few cutters by getting them pinched between the loose piece and the material. Small cutters (3mm or smaller) break fairly easily. Bigger ones, like the 6mm, are really difficult to break when cutting wood, but if it gets pinched, it will burn the wood and overheat, losing heat treatment and becoming dull.
When it comes to small holes, I often pocket machine them, too. Yes, it takes a bit longer and uses up the cutter a bit more, but it saves the time, effort and sandpaper needed to remove tabs in tight holes.
A 20 minute video so someone could tell me to treat my CNC job like a Chinese takeout lol
So that's how you do it! Will you be selling those magic wands on your website Peter? :-)
Right between the left handed hammers and the snake oil. 😉
It can certainly be done with an up-cutting endmill, too, I've done it many times. I've never used a down-cutting bit. I should perhaps get a few of those, as they seem much better for this.
I think that with these small cutters (say, up to 1/4" or 6 mm), it is impossible for a piece to get flung out of the machine with enough momentum that it is dangerous (of course, a CNC router is an industrial machine and there is always risk involved, don't take advice from random people say on the internet, especially if you're worried about safety). What usually goes wrong is that the cutter gets pinched between the loose piece and the surrounding material and that destroys the piece (often in a fairly spectacular fashion, with plenty of smoke and loud noises) and it sometimes breaks the cutter or burns it so that it loses heat treatment and is instantly dulled.
I sometimes use lead weights as gravity clamps to hold large and medium sized pieces, and that usually works very well (just don't forget clearance on the z-axis, haha). It also helps to flatten plywood.
+Krešimir Cindrić
I've never tried doing it with an up cutting bit before. I've never thought of using weights as a hold down either. That's a really interesting idea.
Cheers
Peter
Peter, great video and tip. I have left off tabs from parts before by accident and noticed the same behaviour. Nice to know it wasn't just a fluke.
Joe
That's probably how these things start and then they develop from there.
Cheers
Peter
Haha....... I heard it slip... A future vacuum table build... Wink... Wink
Foot in mouth again. 😩