ERC TimSav - Cheap DIY CNC Foamboard Cutter

Sero

Elite member
Problem with X-axis

I created a Bronco G-code and I messed up on sheet 2 as the width was set too wide and the X went off. Fixed that and X axis still went off, this time it wasn't following the G-code. So I swapped out the driver on the CNC shield for a new one and all seemed good until X-stopped working all together and the heat sink was super hot.
I'm assuming I fried my CNC shield? Anybody experience this?
 

Dudley1001

Member
Its very hard to fry the shield as there are not many components there. Are you sure you installed the driver the proper direction. Also anytime you change a driver you should set the vref max current adjustment on the driver. Also be aware that if you move the gantries by hand, the motors can act as generators and fry the drivers. If the heatsink is that hot then the driver probably toast. Try moving the y driver to that location and see if it works. Good thing is that A4988 drivers are cheap, bad thing is you have to wait to get them. If you fried anything it would be the uno that would take the hit after the drivers. You can also rule out the motors by swapping the x to the y driver and so on
 

Sero

Elite member
Its very hard to fry the shield as there are not many components there. Are you sure you installed the driver the proper direction. Also anytime you change a driver you should set the vref max current adjustment on the driver. Also be aware that if you move the gantries by hand, the motors can act as generators and fry the drivers. If the heatsink is that hot then the driver probably toast. Try moving the y driver to that location and see if it works. Good thing is that A4988 drivers are cheap, bad thing is you have to wait to get them. If you fried anything it would be the uno that would take the hit after the drivers. You can also rule out the motors by swapping the x to the y driver and so on


Driver is installed correctly.
I knew nothing about setting the vref max current adjustment. I don't see any numbers on the stepper motors, I purchased the second kit from Edward. Resistance of the motor phase is 4ohms.

I usually always unplug the motors when moving the gantries, but have forgotten occasionally. Pretty sure that wasn't the cause this time, I feel like it has something to do with the X-axis jamming up when it went out and interfered with the foamboard corner brackets.

I'll give those things a try, thanks for the advise.
 

Dudley1001

Member
Try setting the vref to about .8- .9v and that should be close. If the motors are getting hot, turn it down a bit and if you get skipped steps, turn it up.
 

Sero

Elite member
Try setting the vref to about .8- .9v and that should be close. If the motors are getting hot, turn it down a bit and if you get skipped steps, turn it up.

Vref is set at .6v.

Installed another driver, did a dry run, ok. Cut one sheet all ok, stepper motors at room temp. Started cutting another sheet and 1/4 the way through the driver heatsink got hot and the x-axis stopped.

I think my next step will be to swap the stepper motors.
 

Sero

Elite member
No problems with my x-axis after installing the above mentioned Amazon order. The generic Uno board in that kit did what my first Uno did, randomly stopped, froze and occasionally re-started only to move somewhere very random. Luckily I had a genuine Arduino Uno board and no problems with that. (not yet anyway) So 1 out of 3 generic Unos worked for me.
 

dgraviett

New member
Hi I’m fixing to build this cutter and I have a few questions. I’m trying to figure out what head to build. Seen where a few where talking about the ball bearing head. I watched the video but it doesn’t show it with the motor and needle setup. Does anyone have a pic. or suggest a better head. What jeweler pliers do you use to make the needle. I did a search and there is all kinds of jewelers pliers. And what power supply do you use that wires directly to the shield is it the same power supply that Edward says to use?
 

Dudley1001

Member
I did up a head assembly with balls from a 608zz bearing and it worked well but the vibration of the cutter caused the balls to wear into the the plastic pieces. I went with a different design that uses a small piece of 2020 v-rail and rollers and it worked great. As for winding a needle, most use a printed needle holder that is in the files section on the facebook page. Also be advised that Edward has pulled the files from thingiverse and they are now on cults3d but with a cost of about $20 to download. https://www.thingiverse.com/thing:4785628
 

dgraviett

New member
I did up a head assembly with balls from a 608zz bearing and it worked well but the vibration of the cutter caused the balls to wear into the the plastic pieces. I went with a different design that uses a small piece of 2020 v-rail and rollers and it worked great. As for winding a needle, most use a printed needle holder that is in the files section on the facebook page. Also be advised that Edward has pulled the files from thingiverse and they are now on cults3d but with a cost of about $20 to download. https://www.thingiverse.com/thing:4785628
I have already bought the files off of cults3d. And I don’t have Facebook. There is a stl file that says needle length jig.
 

Dudley1001

Member
forgot about that one. I looked at it but never made one. For length of the needle I usually just cut it just a bit lower than the mig tip then sharpen it with a wet stone. I have used a few different head designs but I am happy with mine as I also use my frame as a laser cutter/engraver and the head design allows me to change between the needle and laser quickly and also has less play in the cutter allowing for very good cuts. I have built 4 timsav's now, 2 as needle cutters and 2 as lasers (for friends). The green foam in the picture was a depron type foam with no paper but painted on one side. The needle cuts are pretty much perfect. I have also copied the needle holder for you. Too bad that your not on facebook, the ERC Timsav group has a lot of info on it from the last few years. Be aware that the FT plans now make it hard to convert for cutting.
 

Attachments

  • TimSav PETG Needle Loop.stl
    13.2 KB · Views: 0
  • IMG_1225 (Medium).JPG
    IMG_1225 (Medium).JPG
    85.5 KB · Views: 0

dgraviett

New member
forgot about that one. I looked at it but never made one. For length of the needle I usually just cut it just a bit lower than the mig tip then sharpen it with a wet stone. I have used a few different head designs but I am happy with mine as I also use my frame as a laser cutter/engraver and the head design allows me to change between the needle and laser quickly and also has less play in the cutter allowing for very good cuts. I have built 4 timsav's now, 2 as needle cutters and 2 as lasers (for friends). The green foam in the picture was a depron type foam with no paper but painted on one side. The needle cuts are pretty much perfect. I have also copied the needle holder for you. Too bad that your not on facebook, the ERC Timsav group has a lot of info on it from the last few years. Be aware that the FT plans now make it hard to convert for cutting.
Better cut than I can do with a knife lol. Looking at your prints on Thingiverse it doesn’t have the motor and needle portion. Is that off a different build?
 

Dudley1001

Member
forgot about that, yes I used a parts from a previous mod. Like I said, went through about 5-6 different designs :) I am a little ocd and was trying for the best cut I could get. I would also suggest the double wheel for the x axis https://www.thingiverse.com/thing:4603770
 

Attachments

  • v_mount_gear.zip
    323.5 KB · Views: 0
Last edited:

dgraviett

New member
I’m trying to source all the parts and most of the links on the parts list are no longer available. Does it matter on the screws if they are hex cap or hex button head?
 

Dudley1001

Member
I don't think there is a problem using any other type of screw heads. I used what I had in a scrap screw box (used to fix CRT monitors) and surplus motors from copiers. The main thing is the screw size as far as diameter goes. I also used sheet metal screws to hold the rails to the end block rather than drilling and tapping.
 

Edwardchew

Active member
Hi guys Happy New Year! Everyone still cutting foamboard with the TimSav? :D

There's a change regarding the 3D STL I have been sharing freely and I have made an announcement below in the FB group.

The last few years have been a very tough environment for my business due to the trade war, covid, war, inflation and the coming recession. It's a 40% yoy drop
2639.png


The ERC TimSav was created as a "Giving Back to the Community" project and I believe thousands have benefitted from the free downloads.
Today, I would like to announce that the 3D Files are no longer free for download. This is so that I could generate a bit of extra income going into the 2023 recession.

I've listed it on Cult3d or Etsy for a limited time of $19.90 for those who wish to download.
Link 1 - https://cults3d.com/.../erc-timsav-cheap-diy-cnc...
Link 2 - https://www.etsy.com/.../erc-timsav-cheap-diy-cnc-foamboard

If you have got the free file already and you have $20 to spare to support me you are more than welcome! 😘

** And I request that those who got the 3D files earlier please respect my work
1f600.png
and not to share it to anyone or on any sites. *this does not apply to remixed version from the fans

Please direct them to my Cult3D page.

Thank you guys!
 
Last edited:

CapnBry

Elite member
My TimSav (link) has been sitting idle for a long time now. The head I designed starts off working really well, then quickly gains slop as the needle wears through the nozzle, and the whole thing has a small chance of wrecking itself while cutting if the wheels holding the tool plate come off. I've been trying to decide what I wanted to do with it since I am not that keen on going back to the CAD drawing board. I do a lot of my own custom DTFB designs though so it would be nice to have a tool that does something helpful though, so I am considering modding it to just be a plotter to draw my plans on the material.

The issue I'd want to resolve first though is dealing with the bowing of the DTFB. I'd previously addressed this with a DTFB vacuum table hooked to a shop vac, and that sort of worked ok, but the suction bits were relatively fragile and I didn't have anywhere to store them so they fell apart quickly. Has there been any innovation in this area? I thought maybe having the toolhead have a couple omniwheels or casters or even just a smooth stainless ball on it that just applied some weight to the DTFB under the toolhead would be enough to smoosh out any concavity of the material, or something along those lines.

I'd also like to point new users to the Inkscape mod I made long ago that allows 4 different depths of cut based solely on the color of the line in Inkscape instead of having to do multiple layers / runs with the cutter: Multicut Inkscake Extension (link)