It's painted, moving, and making dust! #7 - Saskatchewan, CA

[Roadkill_321]

Greg,

I was using a center punch, but I think you are talking about a transfer punch set. You can get them in different sizes to match whatever hole you are trying to copy but I don't have a set. The six rollers are there as Sean says, it gives the Z-slide a little more movement in the Z direction all while always having at least 4 V rollers on the slide at one time.

[Gerald D]

Nic pic John!

Sometimes you just want to pull that slide 2" further up to get a long cutter clear of a thick block on the table . . . . .

To match the holes, I tack-weld the tube to the plate and drill the pilot holes right through from the plate side.

[Marc Shlaes]

Gerald,

Do you leave it "welded" or do you subsequently grind it off and clean it back up?

[Gerald D]

Grind one tack, break the other tack, then
- tap holes in tube, de-burr, paint
- enlarge holes in plate, countersink, de-burr, paint.

You can't leave them tacked because the plate side holes must be clear and not tapped. If you tap through both, the joint doesn't tighten.

[Marc Shlaes]

Duh, sorry. Didn't think that through. I realized it after I read about 3 words in your reply.

Some days you eat the bear and some days the bear eats you!

[Gerald D]

I am very fond of tack-welding. But it must be done with some finesse. When deciding the tack location, consider if you will get a grinder to it for breaking, as well as for cleaning.

[Marc Shlaes]

You have a real talent for making people think...

A couple of (very tiny) dabs of thickened epoxy would work also. A little bit of heat would pop it right apart. the heat wouldn't distort any more than the tack weld.

Thx!

[Gerald D]

If you tack weld something right at its end, it cannot cause any distortion. And that is normally an easy place to get in with a grinder.

[Marc Shlaes]

By the time I get this thing done, I will have your picture on my wall, and J.R.'s and Doug's and Sean's and Mike Richards...

I have so many watching over me that I can't fail!

[Gerald D]

Picture, or stuffed head with a bullet hole behind the ear?

[smreish]

Hey, I work in the theme park world....maybe you would like a nice animated bobbing character of yourself Marc! The sounds of "it's a small world" running in the background makes a nice picture

[revved_up]

First there was the notion of coffee cups, baseball hats, pocket protectors and ink pens. Then came the kilts and coat of arms, now Sean wants to make bobble heads!! I suppose we could velcro a Gerald bobble head to the gantry he could be kinda the patron saint of MechMate.

[sailfl]

Craig,

You forgot the secret handshake.

[Roadkill_321]

Here's another update: The Cable chains are installed.
Cable-Chain-001.jpg
The Mamba supports worked very well, except for the X-axis where I had to do a little clearancing with the angle grinder on the last link of the chain to get it to snap together at a 90 degree angle. That would have been the chain's problem, not the supports.
The chain is Murrplastik, it is very robust stuff.
John
Cable-Chain-002.jpg

[Gerald D]

Hi John

The bend radius on your chains is slightly bigger than what I allowed for in the design. This means that the point where the y-chain attaches to the y-car may have to be lifted a bit if the chain binds on itself when the y-car is over to the y=0 position. You can bend the bracket's point up, or put in a spacer.

The X-chain could have a similar issue - already you had to modify the chain a little, and that has probably cured it.

If I remember correctly, I worked around a 3" bend radius - yours looks nearer to 4"? Very nice for low strain on the cables, though.

[Roadkill_321]

Gerald,
The particular chain that I ordered was the MP3000 Series Multiline chain and I specified the MP3002 chain which has an inside width of 37mm (1.46") and a bend radius of 70mm (2.76"). The problem that I had with the end link on the X-chain was that I couldn't get the end link to snap together at a 90 degree angle. It would go together at about a 45 deg. angle but no more. So I had to grind off a little bit of the end link to give enough clearance between the pivot on the chain and the end link.

The bend radius looks pretty good I think, when the chain makes the loop, the links are snug but not stressed at the pivot at all. Your design worked very well with what I have for chain. Thanks.

[Roadkill_321]

Well, after much trial and error the MechMate has made it's first steps. I have run a few part programs on it and have had no major problems yet. I did have one of the Geckos show a fault at first, but it was due to one of the XLR connectors having two motor wires shorted out. (My poor soldering technique)

Anyway, now I am happily drawing things on the spoilboard with a Jiffy Marker until I get my router and brackets.

John

[Gerald D]

Wise people in Wiseton......delaying installation of the router until you've drawn a few pictures on the table

[smreish]

Whoooo hooo.
Congrats John, fun drawing pictures isn't it?
Happy doodling.
Sean

[domino11]

John,
Congrats on the doodles. Do we get to see some pictures of your graffiti?

Originally Posted by J.R. Hatcher

I found if I moved the skate faster and not allow the metal to heat up it didn't burnish the wheel as bad.

The same thing occurs in my abrasive chop - the smaller area I cut, the less heat, the faster the cut. For example, take a 1/4" x 3" flat bar and cut it laying flat side down. It will heat up, the cut slows down. Then try cutting the same flat bat with it standing on end - it slices right though in no time flat.

david

[Roadkill_321]

Here are the fruits of my labour so far...
Jiffy-Marker-Drawings-002.jpg
The table bed is not quite level as you can see...
Jiffy-Marker-Drawings-003.jpg
Jiffy-Marker-Drawings-004.jpg
I still have a bit of wiring and tidying up to do (OK a lot) but it moves and is predictable.

Drawing pictures with a marker is fun, but I'm still going to get a router attached to that thing.

John

[Gerald D]

John, your z-slide assembly should be rotated 180 degrees inside the y-car. You want the router to be nearest the camera in the first pic ave. And then it would appear that your table top offset is to the far side?

[Roadkill_321]

Yes, you are right. The offset is to the wrong end of the table. I had the Z-axis flipped around in the Y car yesterday to try and remedy the offset being backwards. It will work it will just be a pain to change cutters in the router.

I'm not sure if there is any other remedy short of remanufacturing the table, is there?

[Roadkill_321]

I only just discovered this problem yesterday and haven't really thought much about how to rectify it. I am thinking now that all I have to do is flip the Z around in the Y car, the way it should be. Then pick up the gantry and flip it end for end on the X axis and move the X cable chains to the opposite side. I think that should orient everything so that I dont have to re manufacture the table. Is this the right idea?

[Gerald D]

Your logic in the last post is correct. It isn't a big pain to get it all correct now.

Besides the stretch to get to the cutter, realise you may still have a dust hose and collector foot. Also, it is best for vibration and flex to get the router as near to the y-motor as possible.

Rather fix it now - I'll buy you a drink afterwards

[Roadkill_321]

Thanks Gerald, I'm glad I've got your sharp eyes checking things out for me. That drink will be just what I need.

[Gerald D]

Originally Posted by Roadkill_321

it moves and is predictable.

What more could anyone want?

[sailfl]

John,

Congratulations! It is looking very good.

[domino11]

John,
Awesome pics. Thanks for sharing. Cant wait to see the first cuts.