Thread: New Router Table Build

I'd read Mikes thread a few weeks back and had just started doing the Fusion 360 design work for using a Spindle in a new router table as part of the full shed refit underway so i'm interested in where you are up to Chris, i have nearly zero CNC knowledge but lot's of 3D print experience include design and build of a large delta printer so the linear motion stuff is understood and i was just stumbling big time over did i want to write software control for the RT.

Cheers
Phil

Work has stopped for a lot of reasons, I am doing a house renovation while I can still walk for our later years and I ran up against a few issues I couldn't get my head around for some time. I was using a spindle and Mike used a router and using the same length linear rails as he had was the problem as I could not get the position of the rails and the spindle travel to work out. Longer rails sorted that out.

I have chosen to use threaded inserts for all the fixings and obviously the inserts have to match what is being screwed onto them pretty closely which has caused a few accuracy issues. It turns out that the linear bearing blocks threaded holes vary in dimension on the block and they are also offset to one side of the block, this may be old news to CNC users but I found out the hard way. To get the accuracy I wanted I decided to build an XY table for the drill press because the commercial tables are simply too heavy and have nowhere near the travel required and it will also have DRO's on each axis. I have drawn out the plans in Fusion 360 and using the DRO's it should make things a lot easier. All holes will have to be drilled with counter bore drill bits to allow for any mis-alignment, just another lesson in the whole saga. If using a CNC a lot of this stuff is redundent of course and I wish I had one.

To make the XY table required stuff out of China and the dreaded lurgy hit about that time and it took months for the stuff to arrive but by then I was knee deep in house renos so no progress is the result. It has been a learning experience to say the least. This all started because I wanted an electric lift on my Hammer thicknesser believe it or not and while the RT was one the back burner we decided to use all the electronics on the thicknesser. The smoke escaped from the wires while installation was taking place so eventually Mike will have to look at that as well. He has built a newer and much more simplified version which I will eventually get hold of but he too has had personal problems as well. All in all it has come to a grinding halt but hope springs eternal I am told.

Thanks Chris ... i'm about to run into a similar issue i think with a required bathroom/ensuite reno that will eat up available funds, I actually bought a bench top mill to do the metal work stuff for the planned large format 3D printer and it's DRO gear should arrive in the next week or so so yeah i get the need for accuracy.
You have caught me by surprise on the bearing blocks as i thought you had standard SBR rails guessing 20 or 25mm based on the photo's and all the spec/dimension sheets i've looked at show the holes consistent from each edge with all measurements seeming to be center based..

Anyway my plan is to use a 2.2kw water cooled spindle with an er20 collet set... i'd love a spindle that used a er32 collet set as i already have a full set for the mill. Might be able to delay this a little since i worked out via brute force how the old GMC2050R comes apart so i can do an above table threaded lift.

Have a look at this video, the comments explain that CS fixings are not the way to go and counter boring is the preferred method. I too tried the CS method and without a mill or a dro table it is nearly impossible to get so that the plate when mounted on the two rails slides freely. At this stage was when I stopped and reality took over and I bought some counter bore bits and the XY table build was started. I can't see that doing the layout in Fusion and then trying to put that onto a finished plate was a good thing and believe me I tried. I think I have made three vertical lifts and none of them are what I would call any good. Hours of work for nothing really but the design accuracy is needed because of the threaded inserts I am using.

Thanks for the video, interesting that he could set it up by rotating the slide bearings around, seems like the holes in the bearing blocks are consistent space per se just not consistent to an edge.
Well that sent me down another few hours of utube videos learning even more stuff especially about setting up and using my mill looks like i should order a counterbore set but couldn't find any seller using any shipping faster than 25-49 days .... probably just bite the bullet tomorrow after sleeping on it
I will admit to 3D printing where possible a template to prove various spacings and i'm confident that my printer is more than accurate enough to spot the level of misalignment shown in the video.

Think i'll start ordering parts next week to kick this off

I have found the threaded holes not to be consistent either thus the counter bore need. If you have some blocks do some careful measuring and see how they vary. The block dimensions can be downloaded from the net and surprisingly I found dimensioned diagrams on Ebay. This may be clear enough.


12mm lead screw mount dimension.jpg.

which counterbore bits are you using/planning to use, Chris? The ones I've found all seem to have slightly odd-sized pilot hole requirements, or limited bore sizes...

All the import sets i have looked at either direct via AE or locally on ebay seem to have the same specs, and they are all tighter than the close fit tolerances in the ISO spec but certainly with enough clearance for the socket head cap screws I can buy.
I'm wondering what you mean by odd sizing for the pilot holes?
Cheers
Phil

Originally Posted by Bernmc

which counterbore bits are you using/planning to use, Chris? The ones I've found all seem to have slightly odd-sized pilot hole requirements, or limited bore sizes...

I bought a cheap set from Ebay for the purpose the sizes seem OK but I have not used them yet. It would be easy to adjust the bore for the bolt with a drill if needed and I was only concerned with the counter bore size.

Originally Posted by Aussiephil

I'm wondering what you mean by odd sizing for the pilot holes?l

These are some AE specials - pilots are x.2 or x.3mm. Never used the things, but I have 3mm/3.5mm drills etc - not many of the x.2s

Screen Shot 2020-08-19 at 13.46.43.jpg

The set I bought 7X M3.2-M12.4 Counterbore End Mill Pilot Slot Slotting Milling Cutter Shank XL | eBay

Ah sorry i wasn't considering the x.2 to be odd as the counterbore pilot point has cutting edges and would for hobby/home use effectively center itself on a x-mm nominal hole, fractional .1 steps are available for reaming the drill holes so in normal milling/cnc you would likely just take it to (for example m6) 6mm drill - 6.2mm reamer and then counterbore, well on the cnc you would just do 6.2

Sorry if we are hijacking your thread Chris.

Here is a link to the standard metric counterbore sizings
Counterbore Hole Dimensions Chart (Metric)

in most of the smaller sizes your finish the through hole at the .5 size step for just over a close fit tolerance or maybe if you had some really bad alignment issues then jump to +1 for just over a standard fit tolerance leaving quite a bit of mount wriggle room

Edit: i got a set from an AU seller for around the same price

Originally Posted by Aussiephil

Ah sorry i wasn't considering the x.2 to be odd as the counterbore pilot point has cutting edges and would for hobby/home use effectively center itself on a x-mm nominal hole, fractional .1 steps are available for reaming the drill holes so in normal milling/cnc you would likely just take it to (for example m6) 6mm drill - 6.2mm reamer and then counterbore, well on the cnc you would just do 6.2

Sorry if we are hijacking your thread Chris.

Here is a link to the standard metric counterbore sizings
Counterbore Hole Dimensions Chart (Metric)

in most of the smaller sizes your finish the through hole at the .5 size step for just over a close fit tolerance or maybe if you had some really bad alignment issues then jump to +1 for just over a standard fit tolerance leaving quite a bit of mount wriggle room

Edit: i got a set from an AU seller for around the same price

No apologies needed and the more input the better I reckon. I have the fusion files for the lift but I haven't done the fence drives yet. BTW what I call the fence drive boards and centre lift will be made from 12mm phenolic, it was either that or MDF. I see no problem with MDF as long as it is painted or the water resistant stuff. Phenolic of course can be direct threaded and the inserts done away with. To clarify, my first attempts were in MDF for prototype purposes and as the build went on I decided to use phenolic beacuae I have access to some at the right price.

Originally Posted by Chris Parks

No apologies needed and the more input the better I reckon. I have the fusion files for the lift but I haven't done the fence drives yet. BTW what I call the fence drive boards and centre lift will be made from 12mm phenolic, it was either that or MDF. I see no problem with MDF as long as it is painted or the water resistant stuff. Phenolic of course can be direct threaded and the inserts done away with. To clarify, my first attempts were in MDF for prototype purposes and as the build went on I decided to use phenolic beacuae I have access to some at the right price.

Access to stuff at the right price is always a good thing. At the moment and i have yet to draw it up i'm planning the the z axis to be a modular component likely done with Alu plate and 4040 extrusions, call it a learning exercise for a future 3D printer build. I'll try and keep the parts as off the shelf as possible so others can just take a BOM and duplicate. Hopefully i can make it to be used either with the stepper/automation or via a "normal" above table style threaded rod and lock mechanism.

The spindles are now priced right to use instead of a router in my view and we just generally lack a easy table/adjustment implementation.

A thought on your lift design from the photo's earlier is that the inward facing rails could end up binding easier than if they were mounted more traditionally, can't nail a reason but more of a feel that any movement of the independent sides could cause issues. it also creates a multiplane alignment nightmare as you end up having to align in all three planes rather than two if both rails are on a common plane.