Spindle RPM Suggestions

I have been working through feeds and speeds in the forums and on the wiki for the past two months but I feel like i’m still in the dark. I never seem to get the same results or I am too concerned to stick with them for a full cut. Carbide Create’s feed and speed suggestions always have low rpm speeds. And really to this day I have followed them and have had no issues. Although I run very conservatively as I have it always assume I’m cutting hardwood and normally step back the depth per pass and feed rate. My question is this however:

Most of the feeds and speeds say to run the router at full speed (30k rpms) and cut a little faster than i see in carbide create. Is that always best? I’d like to cut faster but i’m apprehensive.

In my experience, with baltic birch plywood as an example, I am getting away with running between 10k- 15k rpms (setting 2 - 2.5 on the makita router) while Carbide Create sometimes suggests like 8k (for hardwood!?). Normally i’ve gotten away with this doing 1mm deep passes with a 1/8" endmill at 427mm feed at the speeds I mentioned. Just wonder if i’m doing something wrong. I’ve read too many things supporting both methods :stuck_out_tongue:

My suggestion is to use the testing methodology suggested by the Precise Bits folks:

http://www.precisebits.com/tutorials/calibrating_feeds_n_speeds.htm

Start with the Carbide 3D speeds-feeds, increase the feed rate per the testing technique, and thusly arrive at the best feed rate for your machine.

Arguably G-Wizard is the best feed-speed calculator, and it has a setting for the Shapeoko 3 — but the Carbide 3D feeds and speeds are supposed to be tested / vetted and the optimal ones (in terms of being safe for everyone / all machines) — if you don’t get good results with them, please contact support@carbide3d.com with the specifics and we can work it out.

The full speed suggestions I believe date back to the Shapeoko 1/2 days, and the idea was to power through the cut with higher RPMs to make up for the machine’s lack of rigidity — in retrospect, that’s a bad idea — eventually we’ll update the entire wiki for the Shapeoko 3 (and maybe the Nomad?) and a lot of that baggage will be relegated to historical footnotes / pages.

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@WillAdams that has been my ultimate frustration. When I am told over and over to “just use the search function” it can be a complete waste of time when there are 55 entries on 55 different pages (with most, if not all, giving conflicting information). [minor hyperbole alert - - but, you get the point]

I have bookmarked at least 3 separate construction manuals and then been told to ignore them because they are “outdated” and watch the video by Winston Moy. Winston does a great job showing how to put the kit together. The problem is when I am trying to “octopus” some parts together, I cannot keep hitting pause and rewind.

My wish:
A Wiki “Front Page” which shows recently updated and/or archived items. No more outdated information…“This is the most recent information for [insert item name here]”

It would save the “professionals” on this forum so much time and stress not having to tell us noobs to “JUST USE SEARCH!!!”. And, maybe then, I could actually finish building my XL and stop using it as an expensive doorstop.

If you want to improve the wiki, please feel free to request an account and edit it as desired. It’s a community resource and in theory, maintained by the community. I put in as much time as I can manage.

There are very few (probably just the one) person telling people to “just use search” — we’re here to discuss the machines, their use, and help each other. Please direct any such complaints at the person(s) using that phrase. If you wish to flag / report any such posts, I’d be glad to look into them.

The instructions are something of an odd situation, since Edward chose the path which he did — feel free to discuss that directly with him (there’s also the beginning of an effort to make a set of assembly instructions on the wiki: http://www.shapeoko.com/wiki/index.php/Photographic_Shapeoko_3/XL/XXL_Assembly_Instructions — corrections, additions and improvements to that would be welcome. By way of a point of comparison, you may find the Shapeoko 2 assembly instructions of interest: http://shapeoko.github.io/Docs/ and their edit history of interest: https://github.com/shapeoko/Docs/commits/gh-pages

As regards “professionals”, the rules argue against that usage: http://www.shapeoko.com/wiki/index.php/The_Rules_of_ShapeOko

No one is a professional Shapeoko user.1

If you’re having difficulties with your build or your machine, please contact support@carbide3d.com or make a post specifically describing your problem.

I think the real problem is that it’s not a Carbide “current product SO3/Nomad” wiki. It’s a generic Shapeoko wiki and serves a lot of people with a wide variety of shapeoko…incantations. Getting the “old stuff” out doesn’t really work because for a lot of people, that’s the current stuff (built your own). There are really two versions of the S03 now (maybe we should start calling them 3.0 and 3.1?) which adds to the confusion.

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Awesome! thank you Will! That is actually really helpful. ha bit scary as well.

“Continue in this fashion until one of two things occurs. the quality of the cut starts to markedly deteriorate or, the bit breaks.”

I have definitely been able to see the cut deteriorate before I thought I might break a bit but that is a huge fear of mine. I can see how in larger machines it is very possible that the bit breaks before the machine incurs any damage but I don’t know how true that is for the Shapeoko3. Are there any tell tale signs you have seen more specific to the shapeoko that I should definitely revisit my feed and speed?

The nice thing about a belt driven machine is that it’s very difficult to damage the machine, and if one does damage the machine (usually by chewing up a section of belt) it’s an affordable fix (replace the belt) or one may even be able to work around the bad spot (re-position/orient the belt so that the pulley won’t encounter the bad spot).

After using the machine for a while, one will become accustomed to the sound of a good cut, and the appearance of reasonable size chips — those are the big things to be aware of — and always keep in mind the appearance of the final cut — once a part is dialed in, repetitions of it shouldn’t change markedly — if they do, something has changed (likely for the worse) and should be addressed.

Remember, endmills (and to a lesser degree belts) are consumables, and you have to budget for replacing them — best to start w/ inexpensive HSS endmills, then once one has some confidence, switch to expensive carbide.