Here Goes Nothing...

[BobLWeiss]

I decided to jump in and build Joe's model because the machine I have now (which was based on LionClaw's model) was cut out by hand using my wood shop tools but its not 100% lined up right and I can't get it move faster than 40ipm on any axis except Z.

I used 1/2"-10tpi Acme threaded rod from Enco on all axis and EMT pipe for the rails. I am basically happy with it except for the speed. I tried re-aligning the rods once or twice and its not getting much better so I decided to use that machine to cut out the parts for Joe's design and then move all the parts over to this one.

I have a question if someone could help me out, I have access to Solidworks 2007 and converted all of Joe's DWG files to DXF format then used ACE to convert those to GCode. What diameter bit should I use to cut the 1/2" MDF with? Also in ACE it says Default Z Offset -0.750000 and you can change this value. What is this for? And is the Default Max/Z Pass value the amount of depth it will plunge the bit for each pass? It has it at 0.25 as the default, is this good enough or too much you think?

Thanks for the help and I will post pictures as I start building,

Bob

[bp092]

Originally Posted by BobLWeiss I decided to jump in and build Joe's model because the machine I have now (which was based on LionClaw's model) was cut out by hand using my wood shop tools but its not 100% lined up right and I can't get it move faster than 40ipm on any axis except Z. I used 1/2"-10tpi Acme threaded rod from Enco on all axis and EMT pipe for the rails. I am basically happy with it except for the speed. I tried re-aligning the rods once or twice and its not getting much better so I decided to use that machine to cut out the parts for Joe's design and then move all the parts over to this one. I have a question if someone could help me out, I have access to Solidworks 2007 and converted all of Joe's DWG files to DXF format then used ACE to convert those to GCode. What diameter bit should I use to cut the 1/2" MDF with? Also in ACE it says Default Z Offset -0.750000 and you can change this value. What is this for? And is the Default Max/Z Pass value the amount of depth it will plunge the bit for each pass? It has it at 0.25 as the default, is this good enough or too much you think? Thanks for the help and I will post pictures as I start building, Bob

I believe joe will be able to answer some of the questions better but I will do my best. I think that the z offset was -3/4" because you have to set (or should) a safe z for the machine to travel at and rapid rate at. This is a height in which the tool bit can safely clear any obstructions on the cutting table. IE: screws, clamps, etc. 1/4" stepdown is a bit much for a small machine, I like to go with 1/8" - 3/16" max on joe's 06 machine for best results and cut at around 60 IPM for MDF and solids. If you're generating your own toolpaths you can use any size bit you want. I believe joe cuts those parts with a 1/4" upspiral bit to maximize those tight spots in what he can cut. Lastly, welcome aboard!

Have fun, any questions, ask; there are a lot of us here running the machine!

[ger21]

Z offset in ACE is the depth of cut, and needs to be a negative number, which assumes the top of your part is Z=0. What you're calling the safe Z height is called the release plane in ACE, and can be found by double clicking the layer in the priority window.

[BobLWeiss]

Thanks for the help, I just got done converting all of the parts for the Z Carriage and used .125 for the Default Max Z/Pass number and -0.50 for the Default Z Offset. This is assuming I am cutting 1/2" MDF. Does this sound right to you guys? I am going to test cut one of the parts tonight and if all goes well continue on with the rest.

Bob

[bp092]

1/8th inch pass on a 1/2" thick mdf sounds okay, and -.50 would be 1/2" mdf yes. Mdf that I've seen is usually right on, plywoods are all over the place sometimes between units and even sheets within the units. That's why its always nice to cut through the material into your spoilboard a tad (even a few thousands) to ensure you are making it through your material. But the mdf shouldn't be a problem. Sorry for the confusion on the z-, wasn't familiar with ace!

[BobLWeiss]

I see that most people are using the Hitachi router as a spindle for their builds and I was wondering if you can change the brushes on this motor if and when they finally burn up?

I was using an older Sears router for my spindle until I ran a job that flattened my table top and just as it reached the end it burn up and had to be replaced. There was no way to replace the brushes nor get to them easily. I am using a Ryobi router now but want to upgrade to something that will last a long time or be able to be repaired easily.

Has anyone thought of using a motor and making their own spindle? I just read a thread on here somewhere about the same thing but it I am not sure where to get the body for the spindle and how to handle the collet issue. I like the idea of the router because you can easily use different diameter shanks with it.

Bob

[fade2black]

Not sure about replacing the brushes, but I have been abusing a Hitachi M12V in my router table for over 3 years now and it hasn't missed a beat. It probably runs a total of 2-3 hours almost every day too. Best darn router I ever bought and I have a couple of Porter-Cable's as well, but the Hitachi's are one heck of a good router for the price.

[joecnc2006]

I have used the Hitachi router on my machine, going on 1.5 yr and never had a problem, have not even replaced the bushings with the spare ones provided in box yet.

Joe

[BobLWeiss]

Glad to hear it is working that good.. I guess I am going to Lowes tonight!

[BobLWeiss]

I finally got all the parts cut out using my existing machine and began assembling last weekend. The longest part of this build is waiting for paint to dry!

These are some of the parts after painting...

Bob

[BobLWeiss]

I decided to order 1/2"x10 (5 start) for the x axis and 1/2"x8 (2 start) for the y. The z I am going to leave the 1/2"x10 (1 start) as is since the speed is adequate already. I am anxious to see what kind of rapids I get with the 5 start screw on x.. my calculations figure I should see around 300+ ipm on it.

Bob

[joecnc2006]

Looks good, with the 1/2-8 two start i get over 200ipm rapids.

joe