Inventables Community Forum

High feed speeds and only getting dust when i cut

so i just cleaned my shop vac filter recently. i cut exclusively with a dust shoe because i work in my house. and as the name says theres hardly anything other than dust. super duper fine dust to. as opposed to the full on wood chips i get with my profile cuts with my my 1/4inch 2 flute spiral bit.

i know that my 1/8 ball nosed cut are making a ton of strait dust. but i also do alot of vcarving

i run all my cuts at 700-800mm per minute in birch plywood as im still cutting alot of practice stuff and its cheap and fast to vcarve nameplates for my friends. can anyone tell me if the dust is normal. or a sign i should go faster. it already looks like its going crazy fast.

What RPM are you running at? You can try slowing it down if you don't want to up the feed rate.

1 Like

Ditto on lowering the RPM. With small (under .25 inch) bits the Dewalt should be set to a very low speed setting (like 1 or 2). Besides getting the very fine dust you are seeing you may also be burning the wood (and wearing out your bits).

Yeh burn marks and dust is what im getting. How di i determine my rpms in the future with other materials.

And yeh its been at at 6

I have been using GWizard. It took me a couple of weeks to get a feel for how to use it.
What I discovered was it optimizes for the bit which can take a lot more than the machine can.
So I limit the RPM to a lower setting and that gives me a workable feed rate.

Here is a simple Excel spread sheet I built to calculate the Dewalt speed setting based on the chipload recommended and the feedrate.

In most cases you will see that even the lowest speed setting for the Dewalt is faster than recommended when using reasonable feedrates for the X-Carve. So the rule of thumb is just keep the RPMs low and use a feed rate that gives you a good result.

Let me know if you have any questions.

CNC Speed Calculator for Dewalt.xls (38.5 KB)

alright. ill have a go at it in the morning. my windows tablet is the only pc in the house that has my Microsoft office on it. and its got a dead battery.

thanks guys.
and PhilJohnson. that one post actualy made alot of sence. i really wish i could find a tutorial that explains a few things that well. because really ive got alot done in the last month. but im really kinda winging it

1 Like

Hey -

Sorry to be reviving such an old post but I’m hoping you could help clarify something for me since your Excel file seems to show what I’ve been seeing in a lot of places.

It looks like all the manufacturers seem to have roughly the same recommended chip-loads for their bits which end up calculating out to feed rates upwards of 150 in/min for materials like MDF and Plywood (when using a 1/4" bit and setting the router to 1-2). This seems pretty drastic when you compare it to the recommended settings from Easel (40 in/min mostly).

Are these settings more for commercial CNCs and not the XCarve or is Easel just incredibly conservative with its suggestions? Any tips or experience with running the XCarve at higher feed rates?

Also - Glad to see another Ramblin’ Wreck on the forum. Go Jackets!

I had almost forgotten about the Excel sheet I made. But you have a good question. The discrepancy in feed rates is driven mainly by two factors. The first is that the Router most people are using is just way to fast for most of the tools being used on the X-Carve. The high RPM is forcing the calculated feed-rate to be pretty high in order to generate the recommended chip load. But then the second factor kicks in with a vengeance. The X-Carve is a great machine, but it is not a super rigid CNC add that to the relative lower torque of the router and the X-Carve is just not physically capable of running at the faster feed-rates.

So as I have said many times on this forum (in the distant past) - Just make the best of the situation with the tools you have. Unfortunately this means you are not going to be able to generate optimal chip loads. So we reduce the feed-rate to what the X-Carve can deal with and reduce the RPM’s of the router as much as possible and compensate with the only other variable we can really control, the depth of cut.

And for the most part you should be able to get some great results from the X-Carve.

The main reason I made the spreadsheet was to help others realize just how fast the Router was spinning compared to where we needed it to be, I had many discussions with some very smart people on the board (years ago) about what the proper speed setting on the router should be. There was one camp that would just set it to 5 or 6 and leave it there, thinking faster is always better. I hoped that my spreadsheet would help show them that even at a setting of 1 the RPM’s were way to fast for most of the tools being used.

I think for the most part now that way of thinks has been pretty widely adopted.

1 Like

Thanks for the quick reply - That’s super helpful. I guess I’ll just keep playing with the speeds knowing those are the limitations.

I appreciate it.

Mfgr suggested bit parameters usually assume a rigid machine, with coolant/flooding if required and is therefore a best case scenario.

As Allen state, the Xcarve and most hobby machines are not that capable. Also the build quality is different as each Xcarve is assembled by different people, so what works for A may not be good for B.

1 Like