Hi JR,
Take a look at may 4th Axis Indexer Timing Pulley made easy program at:
http://www.cad2gcode.com/pulley
Love your Router, makes me want to build one too.
Bob

This is the latest addition to my router bit collection. I was spending a lot of time making drill bit holders, for drilling simple holes. Today the light bulb came on. It works very good. The 1/2" shaft has to be threaded on a lathe to keep run out to a minimum. This chuck takes a 1/2"
x 20 thread, the capacity is 0" through 3/8". The drill bit in the picture is 1/16"

Pin chucks are also useful.

Gerald with small bits I'm drilling @ 100 ipm. Would a pin chuck hold the bit tight enough to keep it from slipping? If the answer is yes then I will either make one or see if I can find one. I like how small they are. The one like mine is big but can use bits up to 3/8". I think you're right both would be useful.

Never used one either for CNC myself, just wanted to mention that a smaller device, similar to your idea, is out in the market somewhere. I would be hesitant to buy on the cheap side because they may be eccentric - would trust a self-made one, or one made by that JR bloke though. :)

Did buy myself one of these a couple of weeks ago:
http://www.usshoptools.com/current_y...GS_176_180.pdf
and a set of smaller metric collets. Here is the order:

Quantity: 1
Description: 16-SET10 Metric set of 10 ER-16 collets @ $115-00

Quantity: 1
Description: S-E16R06-31N-R collet extension, ER-16, diam.625" X 3.15"long shank, @ $75-00

Havn't had a chance to use it yet.

Are you using it for stitching holes for that boat your building?

Gerald I really like those things. I'll put them on my wish list.

Hennie the full size frames (32') had 1/4" holes to bolt angle alu to. Well the person I cut them for wanted a 25% scale model (8'), so I needed to drill 1/16" holes. I think instead of trying to bolt angle to them, that would be a mighty small screw, he will use wire to hold the batting strips until the resin cures.

An example of stitch & glue boat building

Yesterday I resurfaced my 49" X 97" spoil-board @ 1000 ipm using a 1" bit, cutting 3/4" wide and .040" deep, it took less than 8 min. What a beautiful sight. I had soft limits turned on so it started ramping down about 10" from the ends, made a U turn then back to 1000 ipm.

Careful now JR . . . . . . . . there is a big risk in this . .
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everyone is going to nag you for a video :D

Someone say Video !!:D
That’s a very nice idea !!
Yep, go for it JR, let us see this F1 of yours !:eek:

v id e o video VIDEO common JR dont tease us and then leave us empty handed.. :D

OK,
Well, Im not asking for a video. :) Thats for sure! I would watch it though.

What RPM were you cutting at? 20,000 ?

Geez,at those speeds, it didn't start a fire? ;):D

A Vid would be cool.

Next time I resurface the table, I will video. In the meantime this is the tap file. I do not suggest you run it on your machine, it is configured for mine. However if you do, you do so at your own risk.

This is not a zip file, it only has a zip ext so I could upload it. Simply change the .zip ext back to .tap and read it in 'notepad'.

This was the first time I used soft limits with a cut file. Every other time when the warning box came up that says "you are in soft limit areas, continue, yes, no"...... I always chose no and turned off soft limits. Well I am here to tell you I won't turn it off anymore ............ it worked great. My suggestion is if you don't have 'soft limits' setup in Mach, take the time to do it.

Greg, 3 to 1 trans, 20 tooth sprocket .... ??? I don't know, I just built the thing. ;-) no fire, not even warm. Now that it's broke-in I might try cranking it up next time.

Greg I just gave a little thought to the rpm thing and I believe the motors are only turning about 1000 rpm @ 1000 ipm. If I'm wrong on this somebody needs to straighten me out. ;)

Oops, sorry J.R.,

My question was concerning the cutting bit RPM. :o

Greg I reread you post and now it's so obvious to me that you were talking about the router rpm, can't explain why it hit me as stepper rpm the first time. :o:o:(:confused: And yes the router was running @ 20,000 rpm.

still awaiting your video JR... not cool!!!

Er, Brian, JR said: "Next time I resurface the table, I will video."

Re-surfacing of tables does not happen that often.

I started out about 9 months ago with a 3/4" spoil board. Today because of resurfacing, the spoil board is 1/2". I normally take 1/16" or less during a resurface. The main reason I resurface the spoil board is for better vacuum hold down, the better the surface, the better the hold down, particularly smaller pieces. If it were not for that I could go twice as long without a resurface.

I know he did, but was hoping he might give in and surface for the sake of a video :cool:

Would someone give me some pointers on setting up mach for the laser offsets. :o

JR

If you don't have the link this should help.

http://www.cnczone.com/forums/showthread.php?t=48752

Thanks Nils, it did help.

JR you sent me a PM and I did not realise. Sorry. Check your inbox.

Greg

Who is using 'Sheetcam'?

J.R. do you want to do board processing?

Try (Cutlist) also, I have been using it now for 7 years.

JR, we have Sheetcam. We aquired it purely because it placed tabs so easily and Les Newell (the writer of Sheetcam) was willing to give us a special tab shape and a dxf output. We didn't use it to produce G-code as such.

Resurfaced the table today, and as promised here is the video. Before I ran the machine 1000 ipm. This time I decided not to run it at that speed. I am cutting .050" deep, .75 path. Sorry about the picture quality but it's all I got. :o

http://www.youtube.com/watch?v=EwO_KL1GRww

JR,
That is great! Thanks for the motivation.

Now at 1150 ipm ...... Was wondering about the dust extraction getting switched on ..... :)

GREAT video J.R.:)

JR mentioned before that he is using "soft limits" for that surfacing program, and one can see how Mach ramps the speed down before the gantry reaches the end of the table.

The first thing I did with watching that video was to time the "strokes" against my watch and verify the 1150 ipm . . . . it looks right if the table is 8' long. Not that I doubted JR's word, but because we have had some funnies with indicated speed vs true speed. (In Mach3 r1.84 we had our y-axis running at half indicated speed, In ShopBot we had all axes running slower than indicated).

Another thing to remember is that JR is using "big" motors and belt-drives. Can be considered as "non-standard" for the typical MechMate builder.

And then it must also be realised that 1150 ipm is on the limits. For table surfacing, a lost step is not the end of the world (except for hitting the hard stop on the backstroke). Not a recommended speed for general pupose work. But nice to know that Mach can get it there, and that mechanically it is okay without jumping off the rails or pinions jumping out or anything else nasty like that.

Love the video JR your machine is outstanding. ANd to think most commercial high end machines for the most part cut at or below that speed!

My spoil board is 49" X 97". The jog speed G00 on my machine is 1175 (so I can go faster if I need to):D:p. I have soft limits set at G53 X0 X101 and Y0 Y53. The soft limit ramp up and down is 11.5". It was only running 1150 ipm for 6' the rest of the time it was either ramping up or down :D.
The machine gave no indications at all that it was under the least amount of strain, everything sounded normal, smooth and under control. :cool: I don't think it missed any steps at all. ;) Next time I'll check for that.
The dust collector was on, it comes on with G-code/software. I had been working on the pipe system and did not have the MechMate reconnected, human error :o. I thought the last job (1/8" bit 1/4" material) was a little dusty :confused:. After connecting the pipe it did an excellent job even at that speed and volume.

I made a mistake in my last post. The jog speed on my machine is 1375 ipm not 1175 ipm. :o

Show off. ;)

Heath that will be next time when I surface @ 1375 ipm :p. Maybe I'll even use a sharp cutter. The one I'm using now is dull from when I cutting under the sound barrier. ;)

JR,
Have you looked into the table surfacing cutters available that have the replaceable carbide inserts? When you get dull, you just turn the cutter to another fresh face or replace it. Whiteside has a couple of different sizes and so do a few others.