I’m nearly finished with assembly. The guide mentions a gap between the linear rod supports and the sled when first installing and tightening each of the six bolts until the gap is gone. Does anyone know a rough idea of how large that gap should be?
Mine was around 3/10ths of an inch and as I tightened the bolts, the small top on linear rod support cracked along its arch. There’s still a small gap, but I’m hesitant to tighten more.
This was mentioned in the feedback thread here: Maslow 4 assembly guide feedback - #72 by bar
Wise to wait for analysis from @bar
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Yeah that part shouldn’t crack 
Shoot an email to Anna@MaslowCNC.com and we’ll send you a replacement.
I think that the linear rod needs to be seated a little lower in the sled. I would loosen the clamp on that and give it a couple gentle taps with a hammer.
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Thanks! I’ll email now. I did gently (but also somewhat firmly) tap the rods in when first installing. I will undo the clamps and give it another tap.
I should have measured the depth of the seat and marked it on rod before installing it to be sure I’d reached the correct depth.
The rest of the assembly has gone very smoothly and the guide has been great. Thanks again to the whole maslow team!
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I’m at this part of this assembly where 4buck had some issues. I’m also wondering how much of a gap is expected underneath the linear rod supports. I have made sure that my linear rods are fully seated in the sled and that the top of linear rod supports is also seated fully on top of the rods - yet I see just over a 1/8" gap. As I slowly start to tighten the 6 screws, I notice that the sled gets pulled slightly upward away from the table i’m working on. Loosing those screws levels the sled back again. My thinking is that the gap is too much to properly eliminate by gradual tightening all the way. I don’t want to cause a crack that 4buck experienced (although my gap is less to begin with), nor does the idea of causing the sled to warp a bit seem good.) Curious as to thoughts on a tolerable initial gap amount and whether I should do some shimming with maybe a 2mm thick plastic plate under the linear rod supports? (I think I might have seen someone else post something regards to that but I can’t seem to find that post.) Thanks.
Hey TR7, there was still a small gap when I got my replacement parts hooked up but it closed without a problem the second attempt.
I used a mallet and tapped the rod into the sled and then put the support on the top of the rod and tapped that down as well. I think tapping the support from the top down was what made the difference. The gap was less substantial and tightened without anything breaking.
Thanks 4buck, that’s good to know. So how much of a gap would you say was still there the second time around?
(I ended up taking the rods out, measuring how far they could go into the recess - then got them inserted to that depth and for good measure tapped then down with a mallet, however, I’m still getting the gap of slightly larger than 1/8" and seeing some effects of tightening down this much of a gap.)
I didn’t measure my second gap and I remember thinking that it still looked too large but then it tightened down just fine and I haven’t seen any issues since then.
I realized after the fact I should have measured the recess, marked the rod to that depth, and guaranteed it was fully inserted.
If you measured and hammered, I’d bet you’re good to go. And the assembly guide does say to expect a gap there.
I’m in a position of needing to disassemble my Maslow and reconfigure/finesse the idlers to hopefully alleviate issues with belts not retracing/overly difficult to expand etc.
One of the lingering points that I had during initial assembly was that my supports seemed to be overly ‘gappy’ and had a real struggle to fit. Looking at the machine on the bench, where the supports clip over the rods didn’t feel like a good fit and (although it doesn’t look too bad on the image) there seemed to be a pronounced bend upwards:
As I will need to remove and refit these anyway - aside from being a little more liberal with my mallet - should I expect the tops of the supports to fit flush/flat with the rods? 
Richy.
Yes I don’t think I will get the crack that you got since my initial gap is less. I will go ahead and tighten everything down and observe any notable results - particularly regards to any lifting up of the sled under that area and also any bending of the top part of the support arm - which I noticed in your earlier photo - and just now am seeing another example of in Richyread’s photo as well. Richy, I can definitely notice that upward bend in your photo and I also think that it’s probably not a good thing. It looks like stress on the parts and such things may or may not translate to other issues. I haven’t gotten as far as you with regards to engaging the belts etc, but I am also thinking that these smaller assembly issues can add up to other potential issues. I’m curious if you end up seeing any different results after you have reassembled everything.
I definitely think that I will assemble those parts the opposite way I initially did it; rather than attach the top clip to the arm and then press them into place on the rods, I think I will try fitting to the rods first and see if that makes any difference/noticeable improvement.
I haven’t as yet completed a calibration (my board came without any software installed and I have had real issues with the belts being overly tight and/or slack to the point where one got caught inside the frame) so I haven’t really put it under any real stresses as it were, but absolutely agree that it does look like it’s not fitted properly and could be an issue in the future.
Not sure if I will have time over the weekend to reassemble it all, but will make a note to come back and share some feedback on how I get on.
Richy.
Sounds good. (It also occurred to me to try to attach the top clip after installing the linear rod support, however I wasn’t sure if there’d be enough access space to tighten the horizontal bolts of the top clip. Hopefully there is.)
4buck and Richy, I found that post I was referring to where someone (geertdoornbos) ended up using slight shimming to fill the excess space under the linear support rods. Its a good post to read: Maslow 4 assembly guide feedback - #85 by geertdoornbos
Here is a photo from there. The following words from there resonated with me: “A good fit with no material stress and parallel rods.” I think if one has made sure the rods are seated flush and so are the top clips, and the gap underneath still seems too much to try eliminating by over tightening, the idea of filling in the gap with some solid shimming seems like a potentially good solution.
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Well I did manage to get some time this week to disassemble and refit the motors/idler - it made a noticeable improvement and I was actually able to retract all the belts successfully.
When re-assembling the frame I made sure to pay extra attention to the support rod caps and tried my best to get them level etc.
Removing the caps I could see very faint white line on the inside arches (stress fractures?)
Then with the caps re-attached to the supports the hairline fractures are more noticeable:
And finally after very carefully/cautiously reattaching the supports to the sled…
both of the support caps have clearly now cracked in the inside arch.
I’m absolutely gutted 
I tried to persevere with attempting a calibration run and I was initially pleased to see it actually working (I got a fitness of 0.4 but expected that as I don’t have my final frame setup yet so the bolts were very loose/rough etc. )
But, my feeling of making progress was short lived as upon retracting the belts to pop Maslow to bed for the night…he once again decided to eat one of the belts!
It must be the 3rd time at least now, that I have had to partially disassemble the frame in order to recover from a crossed, jammed or completely seized belt.
I am still quite optimistic given the great posts coming through from other users that if I can get over the calibration hurdles then things should calm down and Maslow’ll start behaving 
(assuming that he doesn’t destroy himself in the process….) but it’s certainly been a frustrating few weeks.
I’m not sure what the best way forward is in terms of my cracked rod support caps . I’m almost exclusively going to use Maslow in a horizontal position - @bar would some epoxy be sufficient to repair them and prevent further cracking/movement or do I need to look at replacing them?
@tr7 thank you for digging out that post - I also think the idea of using small shims for my unit will be useful as, I guess unlike the prototypes, perhaps there just isn’t sufficient flexibility in the final part compared with the 3D printed version as I would also estimate a good 2-3mm gap between the support arms & the sled etc.
Richy
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From he photograph it looks like the shafts are too long, forcing the support caps to flex when you tightened things down. Have you considered grinding the ends down to the 210mm (I think) length? That along with new parts might fix the problem.
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I’m just reading through the other linked thread and that’s the same conclusion I’ve come to thank you 
When I get back home from work I’ll take some measurements to double check.
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Also this part does not seem to matter all that much other than to keep the rods in place (which probably don’t have a lot of contrary force I would think). I think its more for a place to hold onto the maslow than anything else.
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Ron Lawrence wrote:
Also this part does not seem to matter all that much other than to keep the
rods in place (which probably don’t have a lot of contrary force I would
think). I think its more for a place to hold onto the maslow than anything
else.
The rods transfer the forces on the router (from the belts) to the sled, @bar
had issues with the 3d printed prototype sled not being stiff enough, and
therefor the rods would tip instead of moving the sled (which would tilt the
router rather than moving the sled) so he added the linear rod brackets.
the molded sled is much stiffer, so it may not be as sensitive to this issue.
I think the top brackets need to be redesigned so that instead of a cap on the
top of the rod (very sensitive to rod length) it instead clamps around the rod
(not sensitive to length)
David Lang
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I noticed the my rods weren’t “flush cut” so there was extra material on one side of the rod on both sides… Probably adding a 1-4mm of extra length… I opted not to pound it into the sled or the top peice…
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@James_Presnail one of my rods had a small lip of material and I used a file and grinded that down. I do also think there was a slight length difference between the two rods.
@Richyread they were quick to send me the replacement caps after emailing Anna. I don’t know enough to know if glue or epoxy could repair the cracked ones to whatever level is acceptable.
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