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This foam kind of turns to goo if you try too fast of a cutting speed.
about the power supply, i read the geckos wont give more than 67% of the current you select with the current set resistor, so i was thinking 12 amps could cut it. We havent found a power supply yet so were still open to options. Should we do the 16.5 amp + supply?
What about using a variac bridge rectifier and cap as a power supply? dial the voltage and be done with it.
Dylan
If the foam is melting, it's because you're going too slow, not too fast. Or you need a different type of cutter. With the right router bit, you can cut foam at 1000 ipm or more. Melting foam or plastics, or burning wood, is from too slow feedrates and/ or too fast spindle speed.
As for the power supply, it will probably be fine. Doing the math it comes out to around 11a needed. Most likely you'll need less.
I am just now getting into CNC cutters. I have a lot of CAD programs available, as my dad is an engineer. I was wondering if this would be a good starting project? I will mainly use it to engrave tags, and make foam airplanes. It seemed like a good choice as it would be fairly cheap. I have a Wizard which is very similar, and about the same size as a drimle (spelling?). All opinions would be helpful. By the way what is the total cutting area?
Thanks,
Brian
My build is coming along. The linear bearing calls for 0.344 holes for the 5/16 through bolt I measure at 0.301 diameter. Should the dimension be tighter? Is the slop intentional to allow for some misalignment? Thanks
BrMiHi08: The cutting area is about 30" x 15" x 6". A dremel tool would work, but you can only use 1/8" diameter cutters.
carlnpa: I usually made my holes larger to allow for inaccuracies/adjustment. If you made your holes to size and your holes are off by .010, it probably won't work. Here is how I assembled the linear bearings:
For assembly #8, clamp a piece of wood to the side of the angle parallel to the bearing that you want to assemble. Stick a bolt through the hole and put a spacer on the other side. Put the bearing on next. Screw on another nut to hold the bearing on. Don’t tighten the bolt yet. Put a Vise Grip C-clamp on as shown in the image below to preload the bearing and tighten up the nut making sure that the bearing does not pull away from the piece of wood. Tighten up the bolt.
really nice plans...
Actually I don't have a lot of experience in building DIY routers so this might be a stupid question. I would like to use this route also for PCB (printed-circuit-board) milling and I was wondering whether two leadscrews for the x-axis (somewhere near to the bearing on the left and right side) would improve the stiffness and accuracy?
If two leadscrews would improve the stiffness what would make more sense, to use two stepper motors (one for each leadscrew) or just one stepper motor with timing belt?
I m in the process of building this, but I gotta tell you.. You'd better be ded-on on the drilling of the angle bering's holes! Mine got off by a hair and really screwed things up! Thre's a link to a guy in the NL who makes a similar bearing plate.. http://www.zoltar.nl/
Seems like a pretty viable alternative to trying to get angle bars/wood/slots/bolts/etc. trued up..
sorry.. the actual link is http://www.rcmodels.net/cnc/system3/index.html
jgro,
Just wanted to thank you for the plans. I am in the process of building your machine and all is coming together nicely.
Steve
What are the tolerances/accuracy that are being achieved with this design?
Thanks,
I have machine with similar construction. If x-axis is in the one end and you are moving working head in the direction Y-axis, the sledge is not rigid enough. It bends somewhere anyway and the tolerance will go down appr. 1 mm or so. If you are cutting only thin chips or engraving the effect will disappear. So the tolerance depends of how sharp is your cutter, what is the position of x-axis, how much are you cutting and so on. I process wood and can say that tolerance is enough for intarsia. If anybody have an idea how to avoid the problem please speak.
Question about the pipes.. Lowes sells 2 types.. black pipe, and silver pipe.. silver is more expensive, but APPEARS to have a better finish.. anybosy used these pies? Are these what I am looking for? Is one better than the other? I am wanting to start purchasing parts to buld as I can afford them, but can't afford to buy parts more than once.. HAHAHA
thanks. Eddie
Also.. someone suggested a different type of screw fo MDF.. I thought it was something like comformat, or something, but not sure.. it is the type of screw that they use in pre-cut furniture that you have to assemble, i think.. anybody know what kind of screw this is?
Does it really work better?
The black pippe is fine. The "silver" pipe(its called galvinized) just has a zink coating on it and would be of no advantage. The pipe I bought was awfull and I will replace it with drill rod or shafting one of these days. It has pits lumos and dings all over it. Machine still workd remarkabky well.
Garry
I found this in another thread:
Quote:
xairflyer, When screwing MDF together I think the best fastener is a confirmat screw. Here is a link that shows how one guy uses then in cabinet work.
http://www.norrod.com/shop/screws/
You don't need that fancy drill bit, but you need a clearance hole (8mm) for the the shoulder and a pilot hole (5mm) for the threads.
This eliminates the tiring tappping of MDF and holds fantastic.
I used the "silver" pipe, it feels much smoother than the black gas pipe. I used plywood instead of mdf with 1-3/8 deck type screws, these hold really well and are fast. Noted another post that these deck screws also work well with mdf.
Yep, the deck screws work very well indeed. They will split the MDF if not predrilled and countersunk so be careful.
I like the little plastic caps thatconfirmat screws have though.
colin
Okay.. know this is a stupid question, BUT...
regarding the Confirmat screws... you are using these to replace the #10 machine screws in the plans, correct?
also.. which screw size should i buy? -
Small 4x5x8x40mm
or
Large 4x7x10x50mm
Eddie
Still curious about the confirmat screws.. anybody know which size matches up with the screws needed for this plan, and which screw do they replace?
Thanks,
Eddie
I haven't seen the plans, but use them to replace any screws joining a flat to an edge. Either size would be fine, but you have to use the special drill bit, or they won't work properly. Another source is here: http://www.mcfeelys.com/subcat.asp?subcat=20.1.1.1