So having built my C-Beam earlier this year and successfully done some line drawing, life got in the way and I've only just got round to looking at this again.

I've ordered a Dewalt 26200 router which should be here tomorrow and I'm keen to remove some material from some inanimate object with spinning metal.

Initially, at least until I've got a little bit more experience I'm probably just going to mill MDF board but would like to graduate to making some Aluminium plates at some point.

What I'm missing now are the milling bits. Can anyone give me a few tips on specific milling bits that a complete noob like me should purchase to get going with.

The Dewalt has a 1/4" chuck so I presume I need to stick to 1/4" bits, but what types should I look to get?

I'm in the UK and have been recommended to look at GBR Engineering Services Ltd as a supplier and they're local so that's handy.

Any advice much appreciated!

 

Elaire Corporation - Dewalt Router Collets
Look at dewalt 611 for diferent collets you can use.

 

Okay, so I'm probably asking a dumb question here, but can I not just purchase milling bits that will fit straight into the router as it will arrive? Or do I need another collet first?

 

so the router you are getting already has a 1/4" collet so if you got 1/4" bits then you would be fine. If you are going to use smaller shank bits you will need a new collet for that

 

I had the same experience. Took two weeks for mine. Send them an email and see if they've even shipped them, they hadnt when I emailed them.

 

I was delayed for a a few more days. I had to order additional sizes of screws and additional t-nuts. I hope the revisions do not call for another order of parts. I am ready to have this machine up and cutting.

Anxiously awaiting the revisions....

 

Okay, thanks for confirming. I'll plan on buying some Elaire collets in the near future, but for now I'd just like to get something I can use so I'll try and pick up some 1/4" bits for the weekend.

So my next question is what should I pick up for my initial experimenting period? I'm guessing some end mills will do me for now, perhaps a square end and a ball end but what spec for the bits in terms of flutes and material/coating?

Or could I just experiment with a set of simple router bits?

Sorry for all the questions, I'm just keen to make some progress on this project and get it 'unstalled'.

Cheers, Ross.

 

wiring question here. do you need to use (or does it make life easier) a drag chain for the wiring? I was reading on the XL page that there is going to be one but didn't find any reference to one here? I am not anywhere near the wiring stage but kind of need to know.

 

well at that point in the build that I need to get my spoil board down and since I am not using MDF, it's time for some metal work. I have a 13x17x.625 aluminum plate that I am going to cut down to 12x12....now just to do the cutting.

I plan on using the C-Beam itself to true everything up and clean up the edges so I am going to leave things a little long for now. going to have to recess some spots for the screws in the gantry plate as well as setup some holes for bolting it down. going to use 1/4-20 x 1/2 to hold things together

anybody know the best way to cut this? I am thinking my table saw with good lube but am open to other options

 

Table saw will work, but with the right blade. I've been using an 80 tooth Diablo carbide blade in my chop saw and it works great. Something similar for the table saw should work pretty well with a cutting lube. The cutting lube should be a wax based lube (won't get flung everywhere when the blade starts to spin).

If you just want a good level surface, then you may want to look into getting a chunk of cast aluminum tooling plate (also known as MIC-6). It's super flat, and there is a company on ebay that sells 12"x12" slabs for a pretty good price (ssshapirometal on eBay). Their cut tolerance is pretty good, so if you order a 12"x12" slab, there's a pretty good chance it will come in +/-1/16"

 

I think I have a 60 tooth carbide in there right now but not sure. I have a similar blade in my chop saw so I might use that instead since I have a junker one that I don't care if anything happens to it

the plate I got was from a local metal shop and it was a cutoff and a decent price. I am not that concerned with it being super level because I am going to run a surface pass over the top to take care of that. not quite sure yet if I am going to use an MDF spoiler board or get another aluminum plate for that. I am going to have threaded holes in the build plate so either way I would just need to transfer those over so I can screw into them for hold downs

 

Cutting aluminum plate on a tablesaw sounds scary to me. I cut aluminum plate with a circular saw and guide. I use a 7 1/4" 60-tooth carbide blade with a triple-chip grind, specifically made to cut non-ferrous metals. A bit of wax-based lubricant really quiets the blade down.

With the guide clamped to the plate, the piece can't move and my cuts are nice and straight. Both hands remain on the saw so my hands aren't placed in harm's way. I've cut 1" thick plate this way multiple times, as well as a lot of thinner material.

 

that was a lot easier than I expected. put an old 60 tooth carbide blade in and used a cross cut sled and took .125" passes. The only thing I should have done different is worn long pants and my work boots....those chips are sharp and HOT!!

cut quality was very good and it's about as square as my table saw will cut but I oversized it by 1/16 on all sides so I can true it up when I have everything together and I know everything is calibrated correctly

 

Glad that things worked well. The crosscut sled is a great idea.

Yeah, the chips from cutting aluminum are a LOT different than plywood.

 

Continuing with efforts to make the C-beam kit functional and reliable as I am comfortable with, I have posted some extremely naive questions here before. Since I am not mechanically inclined, I decided to look at MY build and try to solve MY PROBLEMS my own way.

Here is what I have done so far.
1. I gave up using the xPro controller for a driver I feel comfortable with and at much lower cost. I use 3 modules of Toshiba TB6600 rated at more than 4amps and 45Volts. The drive module is made by a Chinese vendor named Haoyu -PowerMCU (TB6600 1 axis Stepper Motor 2-phase Driver Board for CNC Router [HY-TB6600-Module] - US $16.00 : HAOYU Electronics : Make Engineers Job Easier) and costs $16 per axis. It can do 16microsteps and no worries about using GRBL Control software version 3.6.1
2. Used a Arduino UNO v3 and uploaded the GRBL 9j.
3. Used a pair of 80mm PC fans to cool the whole assembly just in case. (not necessary as the drivers run cool even at 3amp setting running voltage of 36v).

The whole system has been left running with the spindle off and cutting air (I currently have Bosch Colt palm router that I may change to either DWP-611 or Makita RT0701C) for the past 36 hours doing concentric cycles WITHOUT any issues that I had reported before.

4. In doing so, I found that the Y axis screw has some whipping at high feed rate. I located the problem to the loose fitting of the screw inside the supplied end ball bearing -!!!). I wrapped two turns of 0.002" brass shimming over the screw for a tight fit INSIDE the ball bearing and it is now running very well even at feed rates up to 4800mm/sec. But I have set the values for $110 -$111 (X and Y max rate) at 4000mm/sec and Z ($112) at 2000mm/sec. My step settings are all 400step/mm as I am using 16 microsteps.

5. I now have safe X=300mm and Y=300mm travel which is sufficient for my present use.

I do not know if anyone here has used Homing sequence prior to machining -using mechanical, optical or magnetic stops. I need to home the tool tip and not the table. Any suggestion?

 

tapping (14) 1/4-20 holes in 5/8 6061 T6 is a ***** and tapping fluid is your friend!

 

I haven't seen this tip posted here. Tapping can go a LOT faster than a lot of people think with the right tools. After watching a YouTube video where someone used an air impact wrench to power tap some sheet steel, I've started using my cordless impact driver to tap aluminum wherever I can. The key is using the right type of tap. I'd link the video, but I can't seem to find it at the moment.

Standard taps don't push the chips forward, they tend to wad up in the flutes, so you need to reverse and break the chips regularly. Spiral point taps have a tip that is ground with a cutting edge that forces the chips forward into the hole ahead of the tap. Spiral flute taps are another thing all together. In most cases, they're not something I'd turn to. Spiral flute on the left, spiral point on the right. The angled cutting edge is pretty clear in the picture.



I only buy spiral point taps now, they work fine for hand tapping too. They're readily available at places like Enco and MSC. They're not expensive, about $3 each for the 5mm ones I bought if I recall. To hold them, I use Hanson tap sockets and a 1/4" hex to 3/8" square adapter. I've run both my cordless impacts, the little 12-volt one does fine. I'm sure I will snap a tap this way eventually (especially now that I have said that I haven't), but so far, things are working great. I've power-tapped plates and extrusions for my current 3D printer build, as well as a few things for the C-Beam so far. I've only tapped 1/8" and 1/4" plates, but I have tapped extrusions to the depth of the threads on the tap, so I am sure thicker plates wouldn't be a problem.

The keys?

Only tap through-holes. The chips have to have a place to go.
Make sure your pilot holes are the right size and de-burred.
Use good cutting fluid. I use Tap Magic.
Make sure the tap goes in straight. A tap block can help a lot with this.
Clean the tap between each hole.

 

GREAT info there. I know I don't have a spiral point because the chips were just bunching up so there was a lot of in and out and in and out and I was tapping through holes. fortunately I have plenty of cutting fluid and the more I used the easier things were (duh).

 

got the new tap yesterday (have to love Sunday delivery from Amazon) but haven't used it yet. I DID get everything assembled and did a temp hook up of the electronics and got the beast to move

I haven't decided if I want the electronics attached to the c-beam or in a remote box. If I do the box it will be easier to place the stop switch and protect the electronics a little more. My big issue is going to be dust as this is going to be in a SMALL (read 10x12) woodshop so there is always sawdust in there.

once I get everything working fine and it's calibrated and dust collection is sorted out for it, I plan on enclosing everything to help keep the dust down from the other work I do in there. Guess I need to finish the dust separator project I've been working on

 

My first time cutting 1/4 Aluminum (6061).

Bit: Yonico 31011-SC O-Flute Up Cut Solid Carbide CNC Router Bit, 1/8 x 1/2 x 1/4 x 2"
700mm feed rate
0.20 per pass

 

Thanks!

This forum is the main reason I was able to do this without breaking several bits before I got it right. Thanks everyone for posting detailed speeds and feeds, it helps.

 

looks nice and I assume your DOC was .2mm not .2"

 

Yup, 0.20mm