Connecting rods on fisher

Just broak a few of mine, don't overtighten them

But it got me thinking about a nice spring loaded design based on cloth pin springs, basicly a strong bar with half a cloth pin at eather end, servicing would be so easy.

One of mine broke early on too. I admit that I may have done the nuts up too tight, but at the time, I was focussing more on there being no play with the joint to the balls.
Personally, I believe that the laser cut holes in the ends of the arms are too large on the supplied arms. This requires the nuts to be done up tight, and in my case, the screws holding the balls (on the head and carriages) rubbed on the arms.

I'm lucky enough that I have access to a laser cutter, and so I r-modeled the arms to have slightly smaller holes. I laser cut a 4.5 mm and drilled them out with increasingly larger holes until I was happy with the result. In the end, the holes I settled on were 4.8 mm. Doing this also meant that the nuts provided to act as spacers were too small, however, I found that the new gap was pretty much exactly 3 mm... so I cut the end off of the original arms and used them as spacers. This also meant that the arm pairs didn't bow in the centres. When tightening the screws/nylocs, I did them up as tight as I dared using an allen key and socket, then using only the socket I slackened the nuts until the head of the screw began to spin. I now have no play at all in the arms, and they don't squeal like they did previously when the head was moving.

Edited 1 time(s). Last edit at 08/01/2015 03:04PM by bluesign2k.

I am going ahead with my plan til make new rods, found some 6x6mm aluminium bar and 1x6mm plate, plan to use some 6mm Belt locking spring and a 6mm ball router bit to see if it is posible, will post update when I get the stuff.

I made two cracks on the middle plate where the hex cap crews on. I fixed the cracks by gluing the middle and top.
I cracked on one of front panel while pushing the green icon on it also.

My next printer will have zero acrylic parts and I may upgrade the fisher over time as replacement parts start comming out, that said it's a really nice little starter machine.

Couple of mine broke even though I hadn't tightened them, the breaks looked like fractures. Don't have a laser cutter so I used the spare acrylic to make connecting rods.
Place a rod on the spare acrylic to get the approximate position for one of the end holes then drill it out.
Put the template rod back and use a spare drill pushed through the holes in both pieces to get the correct position for the other end of the rod.
Drill out the other end of the rod and place a spare drill into both end holes.
Now, with the template rod held in place, drill both the inner holes and score the outline of the template.
Place in vice and carefully file to outline.
There is enough spare acrylic to make a complete set. I also epoxy glued one of the broken rods. Both rods are still OK as are all the originals. Three prints so far with no bother approx 3 hours in total.

Good idea to use remnant from the panels cuts for repair parts. However, having only cracked an effector plate repaired with cyanoacrylate, I have thrown out all the acrylic after the build. Should have spared some. A warning in the manual may be needed.

However, I have 3mm styrene panels which may fit better (no risk of cracks).

There is sufficient room on the panels (see here : [github.com]) to print spares for arms, effector and extruder.
That will take slightly more time to cut, but that may save troubles.

Imagin this but with a 6x6mm alu rod and stuff

Interesting!

Just in case anyone needs them, the arms, available in pairs, are here on our webshop: [reprappro.com]
We are now stocking a range of Fisher parts: [reprappro.com]

Ian
RepRapPro tech support

Hey, I just broke one rod today, newbie accident...., i might get the chance to lasercut one tomorrow.. Can i simply use the dxf file and cut the vectors or do i have to change something?

And has anyone thought of doing the rods of CF?

Cheers

I have also broke 3 rods. But i have replaced them with others made from FR4 pcb sheets (that what i have in had 12 o'clock Saturday night). Then work very well.
I am thinking on replace them with rod ends. I cannot find any information about what is the size of the hole of the ball. It needs to be able to be inserted
on the M3 screws of the Fisher.

Hi,

I'm working under creo, and I've try to convert the solidworks assembly with GrabCAD but some parts are "missing" (they are shown but not available for download), the rods for example.

Does someone has already converted it as step or iges ?

Thanks for your answers.

I'm working on making some rods from carbon, Ive already got the carbon rods, just I'm waiting for parts to make the ends, and will let you knowhow it goes

---

RepRapPro Mendel 3 Tricolour
RepRapPro Fisher
-Carbon Arms
-Easy adjust Carriage+effector
-axis stiffness mods
HE3D -600 delta
-Duet 0.8.5
-PanelDue
-DC42 Height probe
-RobotDigg metal components
Simplyfy3D
RS Design Spark CAD

I made the same mistake of tightening up the nuts on the rods after I had gone through the commissioning stage, doh! I've ordered a set of spares from RepRepPro which should be with me in a few days but in the meantime I have been wondering if anyone had looked at replacing the rods with ball sockets and threaded rods? I noticed a number of different ball sockets for RC cars on ebay and was considering buying some to give it a go but thought I'd ask here first in case someone else had already tried/failed/succeeded with this?

Quote
dparker1980
I made the same mistake of tightening up the nuts on the rods after I had gone through the commissioning stage, doh! I've ordered a set of spares from RepRepPro which should be with me in a few days but in the meantime I have been wondering if anyone had looked at replacing the rods with ball sockets and threaded rods? I noticed a number of different ball sockets for RC cars on ebay and was considering buying some to give it a go but thought I'd ask here first in case someone else had already tried/failed/succeeded with this?

see Carbon arms