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.

Yea I did, they are a little pricey for me right now. They use the carbide cutters like metal lathe tool holders use. I think it's a good idea and in the long run I would come out a lot better. All in time :D. Thanks for the suggestion.

I wish I could turn another fresh face when I get dull! :eek:

Life needs to be convenient ;). This is why I made changes in the dust foot.
Dust foot 5th gen:
Attachment 2555Attachment 2556
Most of time I had to raise the Z so I could drop the dust foot to do a bit change :( ..... no more :D.
The black knob is spring loaded and keeps the front half in place until pulled about 1/4", to replace the front you just push it back in until it clicks :cool:.

Dust foot 4th gen here:
http://www.mechmate.com/forums/showt...&postcount=258

Vacuum hold down system here:
http://www.mechmate.com/forums/showt...&postcount=281

Attachment 2557
I also added another blower to create more vacuum for hold down.
Didn't cut anything yet so I'm not sure how much more it sucks, will report later. 1 was working good so I know 2 is going to be even better :rolleyes:.
Thanks Gerald for recommending that I keep all the blowers.

Nice work J.R.,

It's interesting to see the different methods/styles individuals come up with for the dust foot.

At one time, I was all excited about the Z zero device. With the Shuttle Pro and a piece of paper, I can zero the Z in under 20 seconds. It's all personal preference. :)

Yea, it is interesting to see how many ways there are to accomplish the same objective. I like the way yours works. How did you make the hinge? Are you a skype member?

Yeah the hinged one reminds me of that truecnc one (do I dare mention that here?) JR great work what material is the foot made out of?

Brian I made it from PVC 1 X 8 fascia board like Lowe's or Home depot sells. It cuts good and it's light weight.

The hinge is a round outer profile with a step cut into it. A hole is drill thru the two half's for a #10 screw.

Yes, I'm a skype member.

I meant to respond last night, but I was playing with some inlay work. This MM is amazing. The detail is phenomenal and the ease with fabricating inlays is almost too easy.

My machine is doing a lot better, it's not making near the number of mistakes it did when it was younger. Several months ago it was making moves that were totally unexplainable. I tried not to place blame. I reasoned that G-code is a new language to it and it will eventually understand it. Well after several months it seems it has pulled itself together and is acting much more responsible, remarkably fewer mistakes.:eek::rolleyes::D I think it just needed some time to sort things out, or perhaps ... it ... has ... finally ... learned ... G-code.:cool:

It is amazing how these machines learn by themselves as times go by...:p