Question About Astrosyn Vibration Dampers Install

[Rolffeof6]

Hello-

Question about Astrosyn dampers. When mounting the stepper motors in an unmodified RMax V2, the drive gears are all the way to the end of the motor shaft. When adding the dampers, which are 3/16" thick, the motor is moved away from the belt by 3/16 and there doesn't seem to be a way to compensate. Doesn't this introduce a belt/drive-gear misalignment? What am I missing or is this 3/16 misalignment NOT a big deal?

[astroboy907]

From reading others posts, //I think if you flip the drive gears around you get a few mm's more room for the belts//. Let me know if this is possible, I don't have a V2 to test with ATM.
Looking at the V2 manual it seems that the drive gears wouldn't benefit from being turned around. Is it possible to loosen them and slide them out further?

[mechaneil]

I'm building my MAX v2 with three dampers (purchased from AstroBoy907: thanks for the quick shipping). Some notes:

- They're basically two plates with rubber between them. Each plate has two holes (rather than four) to attach to either the motor or the mounting surface. See here for what I mean.

- The plate that screws to the stepper motor has holes large enough to clear the screw size for the stepper. So, two M3 screws are used to mount a damper to its motor. But! the MAX kit supplies M3 10mm screws, which are too long (since the damper's metal plate is thinner than the melamine). I picked up some M3 6mm screws from Home Depot, and they work well.

- The plate that attaches to the mounting surface is threaded for two M3 screws. So, you can use the M3 10mm screws that came with the kit to fasten it to the melamine, with the screw going through the melamine and ending in the threaded damper plate.

- The thickness of the damper pulls the motor shaft back, making it appear shorter. So, instead of mounting the gear flush with the end of the shaft, you have to have the shaft inset by the thickness of the damper, which I think was 0.225".

- Having two mounting points rather than four worried me a bit. I decided that the damper-melamine junction was potentially weaker than the damper-motor junction, so I arranged those two screws such that the axis of pull (the direction that the timing belt pulls) is parallel to the line between the screws. (If that didn't make sense, don't worry about it; it probably doesn't matter anyway.)


FYI,
Dan

[Generic Default]

Make sure that the drive gear is concentric to the shaft too. If it's wobbling from the shorter contact around the shaft, there will be serious layering problems every few cm of your print.

I used cut cork squares for my motors, which are probably less rigid that the special dampers you have. The motor should be tight against the damper so it can't bend or slowly creep over time.

[Rolffeof6]

Thanks to all who responded. Placing my order for the dampers now!

[RegB]

Newbie alert; I haven't even received my first kit yet, UPS has it.

I don't know how thick the melamine is,
but if (if, If, IF) it is thick enough how about;
1) trial fit the motor,
2) draw a thin pencil line around it,
3) remove it,
4) rout out the motor area by the thickness of the astrosyn damper ?

Now, if the damper is 3/16" and the melamine turns out to be 1/4" fergettit, I didn't post this.
(-:

Option B;
Rout out 1/2 or some other fraction of the damper's thickness.

[nitewatchman]

0.260".

nitewatchman

[RegB]

Thanks, that is useful info.
(but BAHH !)
I will probably get my kit 4 days from NOW and - impatient fool that I am, start in on it.
I procrastinated the astrosyn question for too long, although I asked at a couple of places today.
Odd that stores stocking NEMA stepping motors know NOTHING about vibration isolation.

I will scrounge around for alternatives, e.g. grommets that fit over 3 mm screws and aren't TOO thick when squished,
EVA washers, etc.
Whatever I do I will trial mount, measure the shaft protrusion and eventually get the outer edge of the pulley to that spot.

[RegB]

This morning I found some 1/8 inch rubber grommets at the local hardware store.
They look like a fair fit around an M3 bolt, but of course I don't have my kit yet.
(1/8 inch ~= 3mm)

My HOPE is that I can slice them in such a way that the center cylinder/bore part is on one side and the other side is little more than a rubber washer.
IF the melamine needs to be drilled out a bit... I might do that.
If it needs to be drilled/reamed a LOT then I will probably NOT.
I'll likely just slice the center bit off and discard it, i.e. I'll have two rubber washers instead.

I will put the part that finishes up with the center sleeve on the motor side.
I will use washers under the screw heads.
I will practice on a bit of 1/4 inch wood to find the needed drill size.

Wednesday night/Thursday morning - moment of truth (-:

[beilmandesign]

Here is some additional detail as to how I manage my dampner installation:
My dampners were .235" thick. When I measured the gap between the pulley and the stepper motor with everything in the stock position (per the build instructions). The gap was .330". Adding in the dampner thickness gave me a required gap of .565. I used a stack of washers taped together to get to this height. I then placed the pulley on the shaft up against this spacer. While putting downward pressure on the pulley I tightened the set screws. I locltite'd everything.

I also measured how much the pulley projected above the melamine with the stock setup (.700"). After install the dampners and spacing the pulley as per above, I rechecked the pulley projection to insure it was exactly .700" (it was).

Your dampner thickness may not be the same as mine but:
gap when flush with end of shaft......>.330"
dampner thickness......................>.235"
spacer thickness.........................>.565"

[RegB]

I got my astrosyn dampers this morning and set about installing the X tower one.
See previous post, I had sponge rubber gaskets between the motors and the melamine and 1/8 inch rubber grommets under the screw heads, so I may already have a quieter than standard build, longer screws than standard.

Anyway, not too bad a retro fit;
I measured the thickness of the damper to be 0.235, so I set the pulley out from the shaft end by the same amount. I was unable to "sight" the belt line for proper tracking.
I took out the bottom belt roller for ease of access and I took the belt clamp out to give me LOTS of slack.
I clipped the belt ends together with a binder clip from the build plate so I didn't have to re-thread.

Looking at the motor face; the damper is screwed to it at top right and bottom left corners because I figured that top left and bottom right would be the least difficult pair of screws to put back through the melamine.
I am KEEPING the rubber grommets under the screw heads, without them the screws would go into the motor - and I can't find the original shorter screws from the kit anyway.

TIPS; GOOD LIGHT HELPS.
Threading a bit of scrap filament through from the motor side can help hands to find the holes.
Dipping a screwdriver blade in melted candle wax can help philips head screws STICK to it while inserting through difficult places.
A hemostat is a nice needle nose pliers for snaking the bottom right screw into position.

BTW, I noticed that the belt clamp is cracked, so I assembled that very carefully.
Not clear WHY, maybe it was canted when I clamped it down in July.

I have trick trucks on order, so I will probably print the new belt clips for those today and fit the Y and Z motor dampers when the trick trucks are here.
I don't want to go through the belt fitting routine more times than necessary and there is a CHANCE that I cracked one of the other melamine belt clips worse than the X tower one.

Hmmm, I might design and print a couple of belt clips for the cheapskate, for backup.

EDIT:-------later the same day-----
I took the Y tower belt clamp out to copy it, I had hoped to scan it, convert the scan to a drawing, scale that and extrude.
I need to work on that process a little more (-:
So, while it was out I figured I might as well do the Y tower's motor damper.

Bahh, just when I've learned a skill one way I have to re-learn it "left handed" (-:
Again, not TOO bad a task.

I printed a few copies of the belt clamps that I will need for the trick trucks, 15 minutes or so for four of them.
I can't say the printer is any QUIETER, it might even be a bit louder. The sponge rubber gaskets may have been doing a better job.
The clamps came out well enough, I didn't re-calibrate or adjust anything.

[Eaglezsoar]

I got my astrosyn dampers this morning and set about installing the X tower one.
See previous post, I had sponge rubber gaskets between the motors and the melamine and 1/8 inch rubber grommets under the screw heads, so I may already have a quieter than standard build, longer screws than standard.

Anyway, not too bad a retro fit;
I measured the thickness of the damper to be 0.235, so I set the pulley out from the shaft end by the same amount. I was unable to "sight" the belt line for proper tracking.
I took out the bottom belt roller for ease of access and I took the belt clamp out to give me LOTS of slack.
I clipped the belt ends together with a binder clip from the build plate so I didn't have to re-thread.

Looking at the motor face; the damper is screwed to it at top right and bottom left corners because I figured that top left and bottom right would be the least difficult pair of screws to put back through the melamine.
I am KEEPING the rubber grommets under the screw heads, without them the screws would go into the motor - and I can't find the original shorter screws from the kit anyway.

TIPS; GOOD LIGHT HELPS.
Threading a bit of scrap filament through from the motor side can help hands to find the holes.
Dipping a screwdriver blade in melted candle wax can help philips head screws STICK to it while inserting through difficult places.
A hemostat is a nice needle nose pliers for snaking the bottom right screw into position.

BTW, I noticed that the belt clamp is cracked, so I assembled that very carefully.
Not clear WHY, maybe it was canted when I clamped it down in July.

I have trick trucks on order, so I will probably print the new belt clips for those today and fit the Y and Z motor dampers when the trick trucks are here.
I don't want to go through the belt fitting routine more times than necessary and there is a CHANCE that I cracked one of the other melamine belt clips worse than the X tower one.

Hmmm, I might design and print a couple of belt clips for the cheapskate, for backup.

I must have missed the link to the Trick Laser Truck belt clip. If you have a copy or know what link it is could you post it here? Thanks.

[RegB]

Right about here;
http://repables.com/r/424/

They tuck in under the axle holder, BRIGHT BLUE in the pics.

[RegB]

I got impatient AGAIN this morning and did the Z tower motor.
I know, I know, I coulda/shoulda waited for the trick trucks....

Anyway, I want to add another TIP:
If you are anywhere near as ham fisted and klutzy as I am with small mechanical assemblies DO go to http://repables.com/r/424/ and make yourself a few of these BEFORE taking out the standard belt clips.

All three of my melamine ones have cracks, they may be mere surface cracks, they may be structural, I'm not about to push/pull on them enough to find out (yet, though when I get the trick trucks I might P.M. them).
I *suspect* that they may have been canted a bit when I did the 5 hand assembling trick of belt clip, allen key, roller, washer, bolt, belt tension, etc all on one side of the clip - then the roller, washer, bolt, allen key on the other side.

I'm saying HAVE BACK-UP, i.e. three of the new type belt clips that go under the axle holder - just in case you cracked your standard belt clips during the initial build.
I think mine are going to hold, but at least I (now) have a plan B.