WAITING OVER! #15 - Chicago, IL

[zetacnc]

Greg,

Is looking very good!

Keep working!

[edco78]

I noticed in post #47 you had to fill in a gap in a joint. When I was a welder in a steel foundry, I used a chunk (piece) of graphite as a backer on the back side of a hole or gap, and welded the front side to fill it in. It doesn't blow through. The graphite will not stick to the steel. Thought this might help the readers out there.

[Doug_Ford]

Cool. Thanks Gerald. I heard you could use copper but graphic has to be cheaper these days.

[Gerald D]

Welcome Gerald - hope to see more of you around.

You guys are far too exotic - we use aluminium for this. But you have to spell it right.

[domino11]

Gerald, Gerald and Doug,
Yeah I have used copper as a backer to fill in welds, but unfortunately I don't usually have graphite around my shop! I have never thought of using aluminium, is that the same as aluminum? Must be the same just different continent.

[J.R. Hatcher]

Greg, I know I'm a little late with this post but.... I used full nuts behind the guide rollers everywhere instead of half nuts, therefore my racks are bottomed out in some places. I will now go back and turn these nuts down a little in thickness (maybe 1/16"). This will allow the rails with racks to be moved out a little making the rail adjustment better.

Originally Posted by gmessler

Hello Gerald,

Just got back to work on the machine today. I'm working on the y rails and their attachment to the gantry. I marked my rails at 1.81" per the drawing however when I place that line along the centerline of the gantry tube it seems as though the rail hangs way to far out. I thought I'd check out J.R's machine to see what it looked like. To me it looks like his holes in his gantry tubes are closer to the inside.

What amount of clearance should there be between the back side of the rack and the gantry tube?

By the way I welded up my Y car and it turned out just fine. I used a couple of pieces of aluminum, clamped them to the sides to cover the gap, then welded into the hole just like all the others. when I removed the aluminum the weld took on the same shape as the original tab only longer. Afterward I put a slight filet weld on the inside no longer than the tab as you instructed. I'll probably use the caulk to fill the gap so it should look fine when painted.

[gmessler]

Thanks J.R.

Glad to have you back. I used half nuts from http://www.Fastenal.com. That might save you the time and aggravation of turning your own down. I wish I had time to get back to work on my machine. For now I guess I'll have to satisfy my MM craving by watching others build theirs.

[sailfl]

Greg, I think I know what a half nut is but when you go to the website and type in half nut, the search doesn't understand. Can you provide a part # or a better link. Thanks

[garyc]

They are probably talking about jam nuts, They are about half the thickness of regular nuts

[smreish]

The correct fastener nomenclature is jam nut...or hex jam nut. So, if you were to order say a Stainless Steel 1/2" threaded jam nut with course thread you would ask for a SS 1/2-13 UNC hex jam nut. A great book to pick up when your at your local ACE or True Value hardware store is a small book called the pocket reference guide. Very helpful in everything you do from ordering hardware to booking an airline ticket. Sean

[gmessler]

My bad. Jam nut it is.

Hello everyone. Sorry to be gone for so long.

Had a little free time so I tried to pick up where I left off on the beast.

So many changes and so many beautiful running machines. SOOOO many new posts to catch up on.

I started working on the cable chains and chain mounts. For the gantry extension I used a section of wire shelving. For support between the angle brackets I used angle iron. Probably overkill but at least it won't bend.

After reading all the comments on grinding the z plate I made the decision to take the plate to a knife grinder. They did a great job for only $40. Plus I don't have to worry about the bearings in my table saw.

Sorry no pics for now.

[Doug_Ford]

Welcome back bubba. I was wondering what happened to you.

[gmessler]

Thanks Doug,

My job keeps me on the road most of the time but it's great to be welcomed back.

[Gerald D]

Good to have the original Raildancer back!

[gmessler]

LOL

[gmessler]

Here are some pics of the unfinished cable chains on this Classic style Mechmate.

IMG_2958 (Small).JPG

IMG_2959 (Small).JPG

IMG_2960 (Small).JPG

IMG_2961 (Small).JPG

[Gerald D]

Good stuff Greg!

Those are nice trays/ladders you found there.

[sailfl]

I like you cable chain setup also.

[javeria]

me too, the cable chain - nice idea - and looks neat too!

[gmessler]

Thanks Guys!

Got the chance to work on the machine tonight for a few hours.

I decided to work on the z assembly.

I made my 4 support bushings (classic design) I picked up a small metal lathe a couple of months ago. It came in handy for making the bushings. I have a lot to learn but they turned out ok. Wish I had it while I was making my skate.


welded the motor plate and bearing nuts to the spider plate. drilled, tapped, and counter sunk the slide plate/slide tube. I was a little disappointed because while I was counter sinking the plate, the limit lock on my drill press slipped and I over counter sunk one of the holes.

I got the rack cut and drilled but I don't have a bottoming? tap. Off to the tool store.

Got the Stub axle plate made drilled and tapped. I'll give the lathe a workout tomorrow and make the axle. I'll have to counter sink the bolts because I put the cable chain too close and the bolts hit it.

Sorry, no pics again. I'll get something together tomorrow.

That's all for now.

[domino11]

Greg,
Looks more like a fairly big metal lathe.

[J.R. Hatcher]

Greg, a few suggestions.
"I was a little disappointed because while I was counter sinking the plate, the limit lock on my drill press slipped and I over counter sunk one of the holes. " Weld up the screwed up one and re countersink it. Trust me this works . Been there done that.....

"I'll have to counter sink the bolts because I put the cable chain too close and the bolts hit it." Would it work to cut the head of the bolt down in height with the lathe?

[gmessler]

Hi J.R.

Thanks for the suggestions.

On the bolts, because the plate is so close, it would be easier to just counter sink.

On the plate....great suggestion which I may try but my welding is pretty bad. Do you think there would be any issues with the heat in the plate? I'm just using regular steel, not the nice tool grade stuff suggested.

I'll try to post some pics today.

[J.R. Hatcher]

Greg I don't think it would be a problem. Try laying the plate on a soaking wet rag while welding, this will keep it cooler around the area of the weld.

[gmessler]

I tried different bolts in the stub axle plate. It's close but it may be ok. I've included a pic of the plate bolted (without teflon washer) up against the y car.

Here is a pic of the slide plate with the over counter sunk screw.

Here's a pic of the stub for the axle plate and the bearing support base. I had ordered an extra v bearing to use for this but I'm not sure it's going to work.

More later.....

[Gerald D]

For the over-countersunk, a copper washer might do the trick, if you can find one. It should be soft enough to deform and fill the gap.

There seems to be multiple issue with the hold-down roller, but I have to take the missus a 6am cup of coffee now. More later . . . . .

[Gerald D]

First get a suitable sealed ball bearing that will roll under the angle iron of the rail. It is supposed to be a 6304.2RSR, but that is not critical. A V-Roller is the wrong thing in this application, to roll under the flat part of the rail. Two things to check when finding the right bearing:
1. It must be narrow enough to miss the screw heads you used for the cable chain brackets where they are screwed into the side of the gantry. (Or you need to move those screws lower down and shorten the brackets).
2. The outer diameter must be big enough (and the ID small enough) so that the stubshaft will miss the underside of the Y-car. It has been know to grind notches in the shaft and/or y-car to get the clearance.

Then you have the smaller problem of the screws touching the plastic cable chain. You could countersink the screws, or you can dump the screws and weld it together. You could even cut away the bottom section of the bearing support base plate before welding it together.

[Gerald D]

On the over-countersunk of the z-slide plate, you could use longer screws to reach the other side of the rectangular tube. Or even longer and fit nuts on the other side of the tube.

[gmessler]

Thanks Gerald,

I was afraid you were going to say the bearing wouldn't work. After your message last night I figured you had seen something I didn't so I took a look at things again. Under the Y car to see how the bearing was riding. The one side of the "v" just barely made it on the rail. By the time I add the teflon washers it may not touch at all.

I think I'll give the copper washer trick a try. If it doesn't work I'll probably go with J.R.'s suggestion.

[Greg J]

Greg,

I had the same issue with the bolt heads touching the cable chain.

I welded the plate to the pivot plate (forgot proper name) in strategic locations (so it's easy to remove with grinder). My bearing shaft is attached with a "V" head bolt and counter sunk on the outside of the plate.