If your overall thickness isnt a primary concern you just cut a hole out of a piece of material the thickness of what you want your counter bore to be and use it as a shim. Or you could use the same...
Type: Posts; User: stangtjk
If your overall thickness isnt a primary concern you just cut a hole out of a piece of material the thickness of what you want your counter bore to be and use it as a shim. Or you could use the same...
Here's some proof that I actually got something done lol. I still have a bunch of holes to drill before I can start assembling but its a start. As you can see the gantry sides are not exactly like...
I just got in. Spent the past 12 hours in the shop. The gantry is pretty much done I just need to drill a few more holes and weld on the motor/bearing mounts. I ended up going with 1/4" steel...
No its going to be steel, I was going to use aluminum for the sides of the gantry but I think I'll end up using steel for that as well. I was using this chart for the rpm...
Keep in mind this is purely vertical loading. If you calculate deflection from a horizontal load your deflection is going to be considerably more because the moment of inertia becomes much lower as...
Nope no handbook. Quick online search yielded 250 RPM. The drill press at the shop is an old school flat belt driven type, something like this. I'm not even sure what the rpm is for each step of...
You may want to rework that, I ran the calculation using your numbers and came up with a deflection of 0.076"
edit: I ran the simulation in solidworks with simply supported ends and the 70lb...
I think you're using the wrong dimensions for I. Its calculated using the cross section, so in this case your base (b) is the thickness (1/4") and the height (h) is 3" so your moment of inertia is...
Your moment of inertia is way off. For a rectangular cross section I=bh^3/12
I picked up the M8 bolts I needed for the rail today from fastenal. They only had 100pc bags so I ended up getting 2x more than I need but that's alright. I've been thinking of how I'm going to...
I don't think its critical that it be a perfect 90 degrees it's just for support.
The big buttons are usually rated at higher amps and are used to completely shut off power. The little one are usually rated for lower amps and are used to signal an e-stop.
Also I'm not sure what modeling program you're using but I know solidworks will calculate the moment of inertia for you. It's been so long since I've done it by hand I would have to open up one of...
The moment of inertia will depend on the shape and orientation. As I said before the moment of inertia for a solid rectangular cross section is I=bh^3/12. For a hollow rectangle its the same...
Each of these would accomplish the same thing. With out doing the calculations and knowing what amount of deflection is acceptable to you I cant really say what you should use. I big thing to keep...
It really depends on what you're expecting from your machine. You're not going to see really high cutting forces milling pcbs so for that application you're probably not going to see a noticeable...
Using 1/2 steel plate is going to be extremely heavy and a flat piece of steel isn't going to be near as stiff as a piece of square tubing.
With the z-axis you're fighting gravity and all the weight is being supported on the leadscrew and nut. On the x and y-axis the weight is supported on the bearings. People often have the...
I haven't looked into emc2, The only thing I had to setup in mach3 to get them running was the port and pin #s for step and direction. I remember seeing a chart of drives and their timings on a...
That video is pretty cool. I wish my college offered courses in SolidWorks, the only progams they used were ANSYS, ProE, and AutoCAD. The first time I tried SolidWorks it was enough for me to...
Yep, the bearings are for the pulley shafts. I need 2 more, I'll probably just get another pack of 10 off ebay, They were only $12 and some change for a pack of 10 shipped but the same seller...
I got my belts from polytech today. I think that pretty much does it for the parts I needed to order for the machine itself. I still need to pick up the little things like wiring, hardware, etc.
...
I understand how the forces work, I just graduated with a BS in mechanical engineering. It's been a while since I've taken statics so if I'm wrong about this someone point it out and I'll kick...
Have you decided on a particular router yet. I'm still trying to decide on what I'm going to use.
I'd be careful buying a router off ebay unless they are new or cheap. Saving $20 wouldn't really be worth it if the bearing are worn or you have to replace the brushes.
I don't think it's hijacking, he asked how the drives compared so I think it's on topic. I'm not trying to argue with you, I know you weren't knocking the drives, I'm not defending them. I was just...
I'm not sure I agree with that, maybe I'm looking at this wrong but the way I see it all forces resulting from the cutting tool are going to be transferred to the x-axis through your gantry beam....
As I said I'm no expert on the subject but looking at the manuals I still think its a more advanced drive than the geckos. But as I said that doesn't mean they are better suited for a CNC machine....
I'm just the opposite, I like the belt setup better. I don't see any disadvantages over a direct drive and I can name a few advantages.
1. Ability to change out the pulleys for gearing up or down....
You could also just extent the table out past the rails to get the lost space back. That's what I'm planning to do with my machine anyway.