[bjesson]

$236 + Sipping to make the carriage one solid piece. The advantage is it would be as square as my industrial mill so one less thing to align The down side is I have to buy a 12"x12" chunk. Lots of material to remove

billj

[Michael In Cali]

Two thoughts:

Have your existing assembly tig welded. Might not warp too bad.

Make new parts that key together and provide the same rigidity. Might even bond them together with epoxy.

I'm thinking parts 16 and spacers machined from 3/4" plate with a tenon machined in the end of the spacer part. Pocket the #22 and #23 to receive the new tenon.

In my world, I would want to experiment with a carbon epoxy pay-up. But thats down the road a way.

[groswald]

Michael and Bill,

Re: cutting grade 8 bolts - Fibre-reinforced cutoff wheel in a Dremel!

Randy

[bjesson]

Michael and Bill,

Re: cutting grade 8 bolts - Fibre-reinforced cutoff wheel in a Dremel!

Randy

Yuck, eye protection I hope

I used an 18" cutoff saw and let the sparks fly

billj

[bjesson]

Two thoughts:

Have your existing assembly tig welded. Might not warp too bad.

Make new parts that key together and provide the same rigidity. Might even bond them together with epoxy.

I'm thinking parts 16 and spacers machined from 3/4" plate with a tenon machined in the end of the spacer part. Pocket the #22 and #23 to receive the new tenon.

In my world, I would want to experiment with a carbon epoxy pay-up. But thats down the road a way.

I had similar thoughts as well. One other thought was pinning the spacers at an offset to the center hole, same concept as a tenon and keying the parts. This is all after thought stuff since it is already built but for people not at this phase these posts are worth their weight in gold. Unfortunately I didn't join this forum until after I was completed and Bob had mentioned it That should be another selling point for the plans, the designer is at hand! Maybe someday our paths will cross and I can buy him a beer

billj

[bjesson]

Started cutting aluminum clamps for the Bosch router. Doing .0625 depth rough passes right now, gonna take about 2 hours to rough it since it is running at a slow speed right now. Didnt want to overwork the machine on 3/4" aluminum since I am not in a hurry to get it done. So far so good...here's a pic:

billj

[bjesson]

I can safely say it does 3/8ths aluminum so far and no stair-stepping which is impressive for a belt drive.

billj

[R_garza]

That looks awesome. I hope I can get my machine working like that, I'm still working on the aluminum. I didn't drill the holes exactly correct, but I hope it still works.

[groswald]

I made a little (very little) progress over the weekend. My wife seemed to think spending the weekend in the shop was not a really good idea. Mother's Day or some such...

Pictures are linked below.

The first is the electronics package from CNCRouterParts. Very nice, looks to be high quality. The only issue is that the motor cables have very nice molded DB9 connectors on both ends. This means I'll need a large hole in the side of the case to pass them through to the Gecko. I'm still working on a nice way to cover the hole.

Second pic is all of the parts for the left and right gantry sides. They are now assembled. Picture to follow later.

The third and fourth pictures show my method for cutting all the studs. The block of wood is threaded 1/4-20. It is tapered slightly from top to bottom (top is wider) so that the all-thread is held tightly when the face-clamp is tightened. I run the all-thread out to the stud length + 1/16" and then cut it off with a hacksaw. Then a quick meeting with a disc sander to flatten the ends and create a chamfer and voila! I'm sure you can tell I spent a lot of time developing this very useful tool.

The last shot was promised some time ago. Bits from the router I was going to make prior to coming across the Momus plans. The gantry sides are 1/2" baltic birch play laminated with 4 or 6 oz twill-weave carbon fibre and epoxy resin. Verrrrrry stiff!

The Z-axis is 3/8" acrylic. The bearings or 3/8" bronze bushings in HDPE blocks running on 3/8" steel rods. The drive is 1/4-16 Acme with Dumpster hardware.

The Y-axis bearings are 5/8" Igus plastic cylindrical bearings al-la the HobbyCNC plan meant to ride on drill rod. They also ride in HDPE bearing holders. The Y-axis drive is 3/8-10 2-start, also with Dumpster hardware.

It is solid and smooth, but does not have the travel of the Momus. If anyone needs a Z-Axis make me an offer!

The Hubbard and Bolt Depot orders arrived Friday, so I now have all the parts except the router. I won't get to work on it again until Wednesday, so I'll post another update later in the week.

Regards,

Randy

[louieatienza]

I made a little (very little) progress over the weekend. My wife seemed to think spending the weekend in the shop was not a really good idea. Mother's Day or some such...

Pictures are linked below.

The first is the electronics package from CNCRouterParts. Very nice, looks to be high quality. The only issue is that the motor cables have very nice molded DB9 connectors on both ends. This means I'll need a large hole in the side of the case to pass them through to the Gecko. I'm still working on a nice way to cover the hole.

Second pic is all of the parts for the left and right gantry sides. They are now assembled. Picture to follow later.

The third and fourth pictures show my method for cutting all the studs. The block of wood is threaded 1/4-20. It is tapered slightly from top to bottom (top is wider) so that the all-thread is held tightly when the face-clamp is tightened. I run the all-thread out to the stud length + 1/16" and then cut it off with a hacksaw. Then a quick meeting with a disc sander to flatten the ends and create a chamfer and voila! I'm sure you can tell I spent a lot of time developing this very useful tool.

The last shot was promised some time ago. Bits from the router I was going to make prior to coming across the Momus plans. The gantry sides are 1/2" baltic birch play laminated with 4 or 6 oz twill-weave carbon fibre and epoxy resin. Verrrrrry stiff!

The Z-axis is 3/8" acrylic. The bearings or 3/8" bronze bushings in HDPE blocks running on 3/8" steel rods. The drive is 1/4-16 Acme with Dumpster hardware.

The Y-axis bearings are 5/8" Igus plastic cylindrical bearings al-la the HobbyCNC plan meant to ride on drill rod. They also ride in HDPE bearing holders. The Y-axis drive is 3/8-10 2-start, also with Dumpster hardware.

It is solid and smooth, but does not have the travel of the Momus. If anyone needs a Z-Axis make me an offer!

The Hubbard and Bolt Depot orders arrived Friday, so I now have all the parts except the router. I won't get to work on it again until Wednesday, so I'll post another update later in the week.

Regards,

Randy

That is the coolest z carriage assembly!

[bjesson]

very nice Z, too bad it uses acrylic.

billj

[groswald]

Thanks Bill and Louie,

The Z axis does indeed look pretty cool, and it seems to work pretty well. I think it would have been OK. Now we shall never know.

Randy

[momus_cnc]

Maybe someday our paths will cross and I can buy him a beer

Unfortunately I've mostly been away from the computer for the last week, so I'm just catching up on the posts now. A beer would be great! Maybe at the first annual Momus Design convention. I'll print up the T-shirts if you host.

I didn't have a problem with the studs breaking, my issue was the studs freeing themselves from the threadlock.

I'm really intrigued by this problem you had with those studs/bolts not being tight enough and causing racking. Ive abused my machine hard enough to cause the belt to jump teeth and the stepper motors to lose steps, but never had this problem. Or anything else loosening up for that matter. The clamping force that you can get with 1/4-20 threads is pretty high, and there isn't that long of a moment arm putting racking forces against the carriage. Am I just that much more aggressive in tightening nuts than everyone else?

When I installed my studs, one thing I did do was clean out all of the holes thoroughly with a Q-tip. I mostly did this because I am sometimes a supreme idiot, and used dishwashing detergent as a tapping fluid (read about it on the internet, so it must be OK). It did work wonderfully for tapping, but it turns out it is highly corrosive which caused me to spend several hours with Q-tips under running water, cleaning out every hole. So when I put the studs in, the holes were squeaky clean. I also used the "permanent" version of Loctite. These studs are not coming out without the use of heat.

I do like the idea of threading the spacers to act as a locknut. And it would solve the annoyance of them freely rotating all over the place until things are snugged up.

So have you had any more problems with this since installing the 5/16 SHCS?

Those aluminum clamps look beautiful, by the way.

-Bob

[bjesson]

I'm really intrigued by this problem you had with those studs/bolts not being tight enough and causing racking. Ive abused my machine hard enough to cause the belt to jump teeth and the stepper motors to lose steps, but never had this problem. Or anything else loosening up for that matter. The clamping force that you can get with 1/4-20 threads is pretty high, and there isn't that long of a moment arm putting racking forces against the carriage. Am I just that much more aggressive in tightening nuts than everyone else?

When I installed my studs, one thing I did do was clean out all of the holes thoroughly with a Q-tip. I mostly did this because I am sometimes a supreme idiot, and used dishwashing detergent as a tapping fluid (read about it on the internet, so it must be OK). It did work wonderfully for tapping, but it turns out it is highly corrosive which caused me to spend several hours with Q-tips under running water, cleaning out every hole. So when I put the studs in, the holes were squeaky clean. I also used the "permanent" version of Loctite. These studs are not coming out without the use of heat.

I do like the idea of threading the spacers to act as a locknut. And it would solve the annoyance of them freely rotating all over the place until things are snugged up.

So have you had any more problems with this since installing the 5/16 SHCS?

Those aluminum clamps look beautiful, by the way.

-Bob

Hey Bob,

I'm going to just chalk it up to the initial problem being my issue. Once the threadlock broke free I actually worked in reverse to fix the problem. I believe Mike brought up a good point, the stainless steel cap screws were weaker then the allthread. I used the high-strength threadlock on the studs but still broke them free. I can't imagine it being from grease or dirt as I put all parts through the ultrasonic bath prior to threadlocking. They were squeeky clean. You are correct in stating the amount of force that can be placed on 1/4-20 not to mention four 1/4-20 is sufficient enough. the first racking was most likely my bolts not tight enough, second and third racking was most likely the SS capheads "stretching" from over-tightening. But, the 5/16-18 have eliminated the issue completely so no more worries there.

Thanks for the compliments on the aluminum clamps! originally I was using the modified aluminum clamps which I then used to make more precise clamps for the 2401 router which made squaring the bit a whole lot easier, and finally I used the 2401 to make the bosch clamps. Then the Bosch and highly tuned CNC to cut the aluminum clamps. With everything tuned and tightened and no play in the belts I had no "steps" in the sides of the aluminum clamps, everything was dead on. I was able to machine clamps out of 3/4 6061 aluminum with a little patience, I didn't want to rush it since I was still testing if the 5/16-18 cap heads solved my racking issue. Every thing is running smoothly now.

Have a good weekend all!
billj

[groswald]

Between the cold and rainy weather and the vacation day I took on Friday I have made a fair bit of progress.

I haven't been working in the recommended order. Instead, I wanted to get the gantry done and mounted. The first two photo's show the initial test run. The right side was about right, by I was too wide on the left. I took the left side apart, lengthened the slots for the carriage assembly, and remounted everything a little further right. it's now just fine.

Photo 6 shows the right carriage after fixing another problem I had. (Sorry, I loaded the photos in the order I took them) I found that I didn't have enough clearance for the outside horizontal bearings. They scraped all the paint off my shiny mounting angles!

I had to jack the top bearings as far down as I could, raise the right X rail until it was flush with the bottom of the mounting angle, and replace the horizontal bearing washers with thinner ones I found in my bolt bucket. It's ok now, but there isn't much more that an hair to spare! Has anyone else had this problem? I'm not sure I would have noticed had I not painted the mounting rails.

In any case it is all sorted now. The gantry rolls smoothly and is rock solid. It is so smooth that a small hang up in one spot was very noticeable. I couldn't see anything, but could just feel a very slight rough spot on the inside of the right X rail that was causing the horizontal bearing to hang up ever so slightly. Two strokes with a fine jeweler's file and it is now smooth as glass.

Photo's 3 -5 show the electronics installation. I mounted the Gecko vertical and high to keep all of the signal wires as far from the AC line cord as I could. I also put in a terminal block to use as a ground bus. Everything seems to work so far. I have holding-torque on the X stepper.

If you look closely at # 5 you'll see the red LED is lit on the Gecko indicating the e-stop switch has been pressed. It's green in photo 6 having been released.

The sixth picture is Momus in his new home, and least until I can make a cabinet. I was thinking of putting the computer on a shelf above the machine, but that would interfere with the lid. Not sure what I will end up doing.

That's all for now. I have to get back to working on a tall-clock I have in progress for my wife so work on the router will be slow for a while.

Regards,

Randy

[kemper45]

Thanks for posting the photos Randy. I too have a Gecko 540 so seeing how you installed yours is a great help for me. I'm pretty wet behind the ears in the electronics department so I was hoping you (or someone else) can provide a quick description on the how's and why's of the terminal strip as a ground bus. I am trying to follow the various wires in the photos but can't figure it out.

Thanks, Dave

PS Love the paint scheme, mine is going to look pretty drab beside yours.

[louieatienza]

Between the cold and rainy weather and the vacation day I took on Friday I have made a fair bit of progress.

I haven't been working in the recommended order. Instead, I wanted to get the gantry done and mounted. The first two photo's show the initial test run. The right side was about right, by I was too wide on the left. I took the left side apart, lengthened the slots for the carriage assembly, and remounted everything a little further right. it's now just fine.

Photo 6 shows the right carriage after fixing another problem I had. (Sorry, I loaded the photos in the order I took them) I found that I didn't have enough clearance for the outside horizontal bearings. They scraped all the paint off my shiny mounting angles!

I had to jack the top bearings as far down as I could, raise the right X rail until it was flush with the bottom of the mounting angle, and replace the horizontal bearing washers with thinner ones I found in my bolt bucket. It's ok now, but there isn't much more that an hair to spare! Has anyone else had this problem? I'm not sure I would have noticed had I not painted the mounting rails.

In any case it is all sorted now. The gantry rolls smoothly and is rock solid. It is so smooth that a small hang up in one spot was very noticeable. I couldn't see anything, but could just feel a very slight rough spot on the inside of the right X rail that was causing the horizontal bearing to hang up ever so slightly. Two strokes with a fine jeweler's file and it is now smooth as glass.

Photo's 3 -5 show the electronics installation. I mounted the Gecko vertical and high to keep all of the signal wires as far from the AC line cord as I could. I also put in a terminal block to use as a ground bus. Everything seems to work so far. I have holding-torque on the X stepper.

If you look closely at # 5 you'll see the red LED is lit on the Gecko indicating the e-stop switch has been pressed. It's green in photo 6 having been released.

The sixth picture is Momus in his new home, and least until I can make a cabinet. I was thinking of putting the computer on a shelf above the machine, but that would interfere with the lid. Not sure what I will end up doing.

That's all for now. I have to get back to working on a tall-clock I have in progress for my wife so work on the router will be slow for a while.

Regards,

Randy

Looks great! Love the blue rails!

[bjesson]

Photo 6 shows the right carriage after fixing another problem I had. (Sorry, I loaded the photos in the order I took them) I found that I didn't have enough clearance for the outside horizontal bearings. They scraped all the paint off my shiny mounting angles!

I had to jack the top bearings as far down as I could, raise the right X rail until it was flush with the bottom of the mounting angle, and replace the horizontal bearing washers with thinner ones I found in my bolt bucket. It's ok now, but there isn't much more that an hair to spare! Has anyone else had this problem? I'm not sure I would have noticed had I not painted the mounting rails.

Yep, had same issue and caught it same way, red paint was scraped off the top of the angle. I tried cranking down the top bearings to lift the horizontal bearings off the angle but didn't help to solve much since I had already had them adjusted most of the distance to level the gantry. What I ended up doing is removing the angle and milling off about 1/16th of the height and solved it that way. Your almost done, can't believe your going to shelf it to finish a clock! But on the other hand dont blame you for giving in to the wife's demands. Got to pick and choose battles sometimes here too I also don't want to see my tools in the next garage sale. Lookin good so far!!

Billj

[bjesson]

Thanks for posting the photos Randy. I too have a Gecko 540 so seeing how you installed yours is a great help for me. I'm pretty wet behind the ears in the electronics department so I was hoping you (or someone else) can provide a quick description on the how's and why's of the terminal strip as a ground bus. I am trying to follow the various wires in the photos but can't figure it out.

Thanks, Dave

PS Love the paint scheme, mine is going to look pretty drab beside yours.

Dave,

From what I can tell the current wires in his setup are...

From the power supply:
Black/White/Green are the AC cables from wall outlet..Load/Neutral/Ground.
The lower Black and Red wires are the positive/negative driver supply line which depending on the PS will be adjustable up to 36V.

The two black wires below the power supply leading out of the box are a ground and supply line...ground is going to the terminal bus and the supply line is the single black line into the driver.

If you want to use a terminal bus as a grounding bus all you do is short all the terminals together on one side by daisychaning wires to each screw so it is a continuous short on one side and then connecting any ground wires to the opposite side screw terminals will short them all together which helps against floating grounds from happening. The ground bus would be a common ground point for Estop, Limits, and home switches. I don't see much else wired up in his machine from the pics.

Billj

[groswald]

Dave,

Bill pretty much nailed it regarding the wiring. I'll take a few close-ups and post em, probably tomorrow.

The ground bus is definitely optional. You will end up with several wires all coming back to one pin on the Gecko (11, I think). The ground bus just helps keep things neat and easy. I had one laying around and it was easy to do.

Regards,

Randy