[mussersail]

I posted a few questions on my machine build in a slightly earlier post but the title of the post was my question so I'm starting a new thread for the continued progress of build and more particularly questions I have while I move forward.

Update on progress - My initial machine disfunction was entirely my making - I didn't load the newer version of the Mach 3 file from CNC Router Parts. It was nice to jog the machine around. I work usually 7 days a week and probably 100 hours or more so I'm squeezing in the build when I can. With that said, this machine is a tool for my shop, not a toy. Over many years in construction tools have shifted from "cool toy" status, to "how much money is this going to make me..." My 22 year old son, who works for me, is in the "toy" phase right now. So the bottom line is I'm trying to balance making money with building a machine (tool) that I hope to make me more efficient, or at very least, speed production up and improve accuracy and more important, repetitively.

My goal this past weekend was to actually cut something. I put in a temporary small spoil board and cut a simple sign using Cut2d to get familiar with things. Worked great, although I'm still working on understanding positioning and a few other intricacies of Mach 3. My second test was to import a PDF image into Cut2d and make the cut that involved two different tools. Initial cut I was waiting for a tool change prompt or something but I guess this is something I need to figure out. A second attempt loading and running the two different tool paths separately went fine, however, I realized I need to connect the dust collector ASAP. I ordered the Kent dust shoe and the extra air flow adapter for the Hitachi Router I'm using (will get a Spindle when I'm confident I won't f_ck the spindle up). I have a small General Dust collector I am going to try as a dedicated machine for CNC, but if changing smaller bag too often becomes a problem I'll extend the larger shop system. I expect to have this system up and running as soon as shoe arrives.

In meantime... I installed a piece of 3/4" MDF as the spoil board. Since I built a wood table for machine and have no access from underneath I was slightly worried that lining up t-bolts would be extremely tedious and frustrating and wasn't sure if it was even possible. What do most do? Drill and tap cross rails? In lieu of guidance I took the easy way out and drilled 1/2" countersunk holes with a forstner bit and used GRK 5 3/8" construction screws to attach directly to the plywood top of my base. Thoughts? Spoil board is rock solid, but it seamed too easy and am I missing a potential problem? See photos for my screw pattern - should I add more or is sufficient?

Part 2 of this question is surfacing the spoil board. Maybe I'm putting my foot in it, but is this absolutely necessary? I jogged the machine to about 20 different points on the spoil board and used the auto-zero z axis function and recorded the z machine height. There was a .011 variation between the highest and lowest number. I'm a woodworker, not a machinist and plan on using machine primarily for cabinet components. .011 isn't even close to 1/64" and I don't even bother with accuracy less than 1/32" or 1mm given wood movement etc. Again, if this was a hobby I'd probably spend the time and shave off a hundredth but if I don't have to waste the time, tooling, dust,...etc.. I'm not sure if this is a normal variation or generally it is worse. We did use a rotary laser during the entire construction process to level base and then level machine on base with brass shims, maybe that helped?

Looking at cabinet software right now - leaning toward Moziak? spelling? but any suggestions in this department? When dust collection is up and running I'll post an update.



Sorry, can't figure out how to rotate the photo on here - no matter the orientation of my file

[Kosh]

I certainly wouldn't do it that way. You are without a doubt "sucking" the spoiler board down a little and making it not flat. No to mention you only have 1/4" left
of MDF for those screws to bear against. It will tear out on you eventually.

Lining up T-bolts isn't that hard. Just make sure you have your spacing on the cross members and nice even number (loosen and move them with a rubber mallet to get then close to perfect).

Then just draw lines at the same spacing on your spoil board, and pre drill a slightly oversized hole ( and countersunk!) for the T bolt to come through. Takes a little playing around
to get them all lined up and through the holes, but it works well.

The hard part of course is that if you don't have t-bolts, you have to use T-nuts like I did (can't install them afterwards very easily!). So, I did this. I got some all thread and made long "studs" which I put into the t-nuts, and used for threading through the spoiler board holes. Then, once the board is in place and with the t-nuts under the holes, you CAREFULLY unscrews the studs and replace with a regular bolt that goes into the T-nut.

Then YES, you need to surface you spoiler board. Think about this, you will eventually want to cut a outline profile with tabs/onion skin, and you want it to be accurate for that.