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View Full Version : Got a quote for 7k can I make it for 500?



Gtee87
21-02-2014, 02:03 PM
Hi first time poster here.


I'm looking to create a new business this business involves cutting small pieces of cardboard around 3 and 7 mm thick into complex shapes.


I have a very modest budget of 500 I recovered a quote from a company staying that 500 wouldn't even cover the cost of the software and that 7k is a more realistic budget.


I really want to start this company but I have no chance if the CNC machine is going to cost anywhere near 7k.


I am a marine engineer to trade and don't mind making this a DIY project I just want to know if it can be done for my tiny budget ?.


Thanks

gavztheouch
21-02-2014, 02:35 PM
Hi welcome to the forum,

Do you have a sample pic of the type of cutting you wish to achieve.

Have you heard of maker spaces or fab labs, this might be a good way of accessing/(hiring time on) machines at a low cost to see if your bussiness is viable. This way you can also try out different machines to see what you might want to buy or build. There is a big variety of machines out there, laser cutters, 3d printers, routers, mills, etc

Gtee87
21-02-2014, 02:52 PM
Hi welcome to the forum,

Do you have a sample pic of the type of cutting you wish to achieve.

Have you heard of maker spaces or fab labs, this might be a good way of accessing/(hiring time on) machines at a low cost to see if your bussiness is viable. This way you can also try out different machines to see what you might want to buy or build. There is a big variety of machines out there, laser cutters, 3d printers, routers, mills, etc

Hi Gav

thanks for the quick reply , I don't have any pics as of yet was hoping to try and prototype with my own personal machine , basically its cardboard cut outs got nurseries and stuff so little teddy bears, guitars that sort of thing , maybe even some 3d creations with cardboard.

i saw this video http://m.youtube.com/watch?v=P8jbtRTV6uw

it looks perfect for what I'm wanting I just want to understand how I can get the machine and cutter like the one in the video above for around 500

thanks again

Gtee87
21-02-2014, 08:45 PM
Yeah that's a great idea thanks I will try that. I'm looking to be able to use the cnc machine like this video
http://m.youtube.com/watch?v=P8jbtRTV6uw
If I could get a system like the one in this video for around 500 I would be happy.

gavztheouch
21-02-2014, 08:56 PM
Have you looked at using a laser cutter much faster and cleaner.

Gtee87
21-02-2014, 09:08 PM
Do you have any videos of these ? And would this not leave burn marks on the cardboard I was trying to do this as clean as possible as the final product will be the cardboard it won't be painted or covered ?

JAZZCNC
21-02-2014, 09:43 PM
No is the answer to your question.! 500 won't be enough to do it correctly.
If you do try to make it for 500 then you'll only end up wasting money has it will mean buying Cheap sub standard components that give nothing but grief and won't last very long or under perform. It's false Economy and mistake often made by new people trying to do it on the cheap.

1000 is a more realistic figure for any machine that will be worth doing and even then you'll need to be very savy with what you buy and do all the work your self.

routercnc
21-02-2014, 09:47 PM
How about as pastry cutter tool (in the shape you want) and a fly press?

If you want a cnc machine for 500 that is a very low budget. Using some very low-end bits you might be able to knock something together (e.g. wood frame, gas pipe rails, home made v-bearings, all-thread leadscrews. . . .) but it would not be much good for anything more demanding. But that might be good enough for cutting cardboard with a drag knife.

JAZZCNC
21-02-2014, 09:47 PM
Yeah that's a great idea thanks I will try that. I'm looking to be able to use the cnc machine like this video
http://m.youtube.com/watch?v=P8jbtRTV6uw
If I could get a system like the one in this video for around 500 I would be happy.

The Drag knife alone is $229 and to do it correctly like you see in the video you need the software or know how to modifie G-code.

Gtee87
21-02-2014, 10:00 PM
How about as pastry cutter tool (in the shape you want) and a fly press?

If you want a cnc machine for 500 that is a very low budget. Using some very low-end bits you might be able to knock something together (e.g. wood frame, gas pipe rails, home made v-bearings, all-thread leadscrews. . . .) but it would not be much good for anything more demanding. But that might be good enough for cutting cardboard with a drag knife.

Thanks for this I am really starting to believe that I should go with a manual approach until I get some traction and cash to go for the full CNC machine . Only thing is how do I make the cutters and can this be done to cut right through cardboard ?

m_c
22-02-2014, 12:13 AM
Seeing that vid has just given me an answer to a problem I'm facing!
I may now have to build a router frame...
.
You could make your own drag knife, although if you're wanting to cut thick card, a tangential knife setup would work better although is good bit more complex.

deisel
22-02-2014, 01:47 AM
Thanks for this I am really starting to believe that I should go with a manual approach until I get some traction and cash to go for the full CNC machine . Only thing is how do I make the cutters and can this be done to cut right through cardboard ?
In that case depending on the number of each type/card cutting you want to cut would stencils made out of alu plate say 5 mm thick be any good layed down over the card and a couple of hand tools knocked up..small rollers on the end with a blade that can be adjusted for depth of cut..

Tenson
22-02-2014, 02:02 AM
What size parts do you want to cut?

You might be able to do this with a second-hand CNC3040 and narrow endmills. Probably no help for production but could do some prototypes I imagine. A new CNC3040 could be had from eBay for ~650. I know they are not sturdy machines but for cardboard it could be easy and cheap.

GEOFFREY
22-02-2014, 09:12 AM
I think that cardboard requires a drag knife,not a rotary cutter. I have log believed that a drag knife blade could be held in an unpowered spindle would work in a small cnc machine and did indeed intend to try this, but have never yet got around to trying it. My wife uses a a card cutting machine (craft robo) which works well for THIN card, sadly however the blade diameter is too small for my i/8" collet chuck. My intention had been to try to get one of my many (too many) broken 0.5mm cutters reground with an offset point, but the road ro hell is paved with good intentions!!! I still think it would work though. G.

Clive S
22-02-2014, 09:31 AM
My wife uses a a card cutting machine (craft robo) which works well for THIN card, sadly however the blade diameter is too small for my i/8" collet chuck. Dremel and others make a very small 3 jaw chuck that might hold .5mm you might be able to hold the chuck in your collet with an adaptor. Just a thought. ..Clive

JAZZCNC
22-02-2014, 11:01 AM
You could make your own drag knife, although if you're wanting to cut thick card, a tangential knife setup would work better although is good bit more complex.

M for drag knife to work as good as it does in the video the knife has to do litle U turns at each corner to orientate the blade. If you check out the site or do a search there is the Code which does this for you and alters the G-code file.

They do work without it but no where near as good as it looks in the video. Tangential Knife is best option but defeats the Cheap requirement.!!

GEOFFREY
22-02-2014, 12:08 PM
Dremel and others make a very small 3 jaw chuck that might hold .5mm you might be able to hold the chuck in your collet with an adaptor. Just a thought. ..Clive

Thanks Clive. You have slightly mis-understood what I meant. I use PCB type end mill cutters which all have 1/8" shanks. The 0.5mm cutters have a very short length of cutting flutes so the broken ones leave quite a long length of 1/8" solid carbide shank to regrind as a dragknife with a decent offset to get the knife to follow. from what I read into the comment from Jazz, this may well work, but would benefit from using a modified G code. G.

JAZZCNC
22-02-2014, 12:24 PM
from what I read into the comment from Jazz, this may well work, but would benefit from using a modified G code. G.

Yep Geoff if you watch the video carefully you can see the machine Jiggle at the corners doing very fine moves so the blade orientates to the direction to cut.
It almost looks like Tangential knife because blade spins before moving in direction of cut but the rotation comes from the machine movements not the spindle and the blade is just held in an Offset holder which spins in bearings held in outer assmebly that's held in spindle collet.

Without this extra code to orientate the blade it can tear or pull sharp corners.!!

EddyCurrent
22-02-2014, 12:49 PM
So does anyone use a stepper motor to hold the knife so that it can be turned using G code as if it were a 4th axis ?

GEOFFREY
22-02-2014, 03:15 PM
Eddy, the blade is normally freely rotating and follows like a supermarket trolley castor. I think that Jazz is only referring to sharp turnsetc. for any code mods. G.

JAZZCNC
22-02-2014, 03:23 PM
So does anyone use a stepper motor to hold the knife so that it can be turned using G code as if it were a 4th axis ?

Yes that's the way Tangential works, Mach as an option to use an Axis for Tangental moves.

Edit: Heres a vid of Tang knife and site to look at with some info. http://www.rockcliffmachine.com/forum/showthread.php?440-tangential-knife-cutting-Styrene

http://www.youtube.com/watch?v=aY3h352Lhn4

Swarfing
23-02-2014, 12:08 AM
Check out this guy who does exactly what you want to do by the looks of it. His machines are quite light weight but adequate for the job and he makes drag knifes also.

DonekTools - YouTube (http://www.youtube.com/user/DonekTools/videos)

m_c
23-02-2014, 01:05 AM
Swarfing, that's the same guy as the video we discussed on the first page. It would appear Donek have more than one youtube account.

Swarfing
23-02-2014, 02:22 AM
I missed that link so i just checked it out and so it looks like he is into snowboarding as well.

GEOFFREY
23-02-2014, 03:59 PM
Just for information. This morning I took a blunt 1/8" shank 30 degree engraving cutter, ground a new point slightly offset to the centreline - don't know what the the offset was as it was only done by eye on a green wheel, but probably about 0.3mm and ground the face opposite the flat face down to form a point - I hope that makes some sense. I then used temporary tack adhesive to stick a 0.25mm A4 acetate sheet to a self healing mat, drew a cutting program for 40 of my 1/12 scale streetlamp head glazing panels, edited the spindle start out of the code in the post processor and ran the program. Result? I now have 80 lamp glasses (I ran the program twice). The cut is quite acceptable and the cutter was clearly following in the cut direction and swiveling nicely at the corners. To be fair this was a very simple shape - just a trapezium with the four corners cut back to clear any excess solder I get when building the lampheads. The first sheet I cut at about 1500mm/min and the second at 2000mm/min. I do not think the speed made any difference, but I was trying to hold each cut piece in position as I had used the "tacky" very sparingly so that there was not much adhesive to clean off. There is no noticeable "dobbing" of the corners and no alterations were made to the G code. g.

Tenson
24-02-2014, 02:30 AM
If the blade can be held freely rotating (I had assumed it needed a dedicated motor) then the CNC3040 could be adapted easily, surely? Just don't power the spindle. If it's big enough that is.

JAZZCNC
24-02-2014, 02:42 AM
If the blade can be held freely rotating (I had assumed it needed a dedicated motor) then the CNC3040 could be adapted easily, surely? Just don't power the spindle. If it's big enough that is.

Yep I agree and cutting cardboard is a great use for this machine. Still wouldn't buy one my self but yes I agree in this case if he could find a cheap second hand machine then it's worth a stab.!