[Jason Marsha]

Here is the bracket I promised. I am not sure how smooth the curves as I did no editing of the dxf file before converting it to G-code.

Jason

[Lionclaw]

Zoltan,
The supports are not perfect as I drew them with my rather poor CAD skills. The one with the 5 cutouts although not perfect are copies of each other.

Lionclaw,
Did you have a problem with stripping the threads while using the drill?


Jason

So long as I didn't run the chuck into the piece, the threads would work out just fine. The threads in the adjuster blocks eventually came out though and I went to UHMW PE instead of MDF. I threaded the PE blocks with the drill though too

[Jason Marsha]

Had to do some running repairs to the JGRO today, the bolts holding the aluminium angle to the MDF blocks had started to loosen up. After months of hard running I suppose they had to loosen at some point. The pics show threaded inserts in the face of the MDF, this was done since constant removal of the Z axis plate would have stripped out the threads eventually. if you are going to put threaded inserts into the face of MDF you must clamp over the hole with a c-clamp and then screw them in so as to prevent the MDF from seperating laterally, as it is very weak along the fibres.

Jason

[Jason Marsha]

I cut a simple design in my MDF drawer faces using the Spiro program that Splam wrote. I ran the code twice so that the router would clean up a tiny flaw at the deepest end of the cut. Maybe I should slow it down some more to 508mm/min (20" min). I scaled the smaller design up 1.25 times to get the larger design using NC-PLOT.I will get a clear picture of the error from another drawer face and post it.
I suspect the X-axis rails (attached to the Z axis) are weak and I may repalce them with shafting rod if the correct size is in stock at the metal supply.

Jason

[ShayArnett]

Whats the specs on your motors and what driver are you using?

Trying to guesstimate what my speeds will be like.

[Trainhound]

How accurate is the machine? about how much did it cost to build?

[Jason Marsha]

ShayArnett,
Its the Hobbycnc kit with the 127oz/inch motors 3.6 Volts 2 Amps. I choose to use the 24Volt transformer. Go for the 200oz/inch motors, the only reason I have the 127oz/inch is that the 200's were out of stock at the time.

Trainhound,
I do not live in the USA so my price would not apply to you, but I've seen somewhere on this site a price of approximately $500.00 including electronics.
As for accuracy I don't have a figure but after engraving my dog's tags with all the fine lines of the letters matching up perfectly, that was good enough for me.

Jason

[ShayArnett]

I already have 276oz/in autmoation direct motors and a 24v freebie powersupply i will be using. My machine will be using 1/2x10 acme and I have been trying to decide between direct coupling or gearing 2:1 to double my speed. But I should be able to cut double what you are cutting with the 1/2x10 instead of 1/4x20 so maybe i'll be happy with it for a while Probably be alot safer too not having 30k rpm spindles zipping around at 120 ipm while i'm still learning to program

[Jason Marsha]

ShayArnett,
It would be great to see what speeds you can achieve with direct coupling of acme rod as I may upgrade to this option with a change of motors. I suspect at 120ipm you may have to deal with some whipping. Also remember that the faster a stepper spins the more torque it loses therefore gearing 2:1 may cause you to lose significant torque even with the 276oz/in motors.
Keep us informed, we look forward to lots of pics and build updates.

Jason

[Jason Marsha]

Searching the storeroom yesterday I came accross a chair destined to be dumped at some point(I am a pack rat). The folding chair was in need of a foot so I decided to try to model the part and see if I could actually save this chair. Before anyone asks, glue would not work as the plastic is very hard and got slightly deformed during the break.
I am planning to use 1" thick cutting board plastic for the replacement part. The white stock I used for the test part is some type of signage stock, the name I have forgotten.

Jason

[spalm]

Jason,
It has been fun to watch your work. I really like your support mod to the long axis using threaded rods. It is simple and not to “over engineered”. Good job. You a smart thinker.

You seem to be having a blast, and really using your machine.

Thanks for the inspiration,
Steve

[Jason Marsha]

Thanks for the kind words Steve.
Yes I am am having a blast with the machine and I try to use it everyday. I just drew up a motor plate like you used on your machine so that I could line up my X-axis (short) threaded rod and motor more easily. I should have some pics of that tomorrow depending on work load.

Jason

[WarrenW]

Jason,

I also like the idea of using the 3 threaded rods holding the sides tight. Is the piece of wood on each side of the black pipe being used for the pipe? I guess this prevents the pipe from flexing any?

Thanks,

Warren

[Jason Marsha]

Yes that piece of wood fills the space between the "pipe" (seamless shafting rod) and the sides of the machine thereby preventing outward movement when the gantry passes by. There is also a piece of wood supporting the pipe from below to prevent any sag. The shafting rod is very rigid but the cost to support it just in case was negligible.

Jason

[Jason Marsha]

Well it had to happen, the lead nut failed and has to be replaced. :violin: As luck would have it I had a spare knocking around. It was the first nut I ever made just never used it. This gives me a chance to show the bottom of the table with the T nuts as well as inside the base of the machine. The tensioner part of the nut is still good but the nut is stripped out, how strange. I am thinking this would be a good time to change this axis to 3/8-16 threaded rod but that would involve trying to find a latheman to cut the ends down to 5/16" to fit into the bearings and the machine would be down for a little while, oh well.

Jason

[Jason Marsha]

I have to change the threaded rod as both ends have burrs on them which would damage the threads of the leadnut. To speed up the process I will stick with the 1/4-20 thread for now but in stainless steel, hopefully the whip should reduce. I cannot find acme rod in my neck of the woods but in time I will aquire some.

Jason

[joecnc2006]

I have to change the threaded rod as both ends have burrs on them which would damage the threads of the leadnut. To speed up the process I will stick with the 1/4-20 thread for now but in stainless steel, hopefully the whip should reduce. I cannot find acme rod in my neck of the woods but in time I will aquire some.

Jason

I used 5/16-18 but modified my anti-backlash nuts to use actual nuts within them, and just keep it lubed, they work really well and have several hours on them and have not had to adjust or replace them yet.

http://www.cnczone.com/forums/showpo...9&postcount=60


Joe

[Jason Marsha]

Thanks for the tip Joe. I have changed again and will now use 5/16-18 as I got some couplings done today, cannot find it in stainless 6' long though. I will post the picture results tomorrow.

Jason

[scorpio2367]

Jason Try www.mscdirect.com for you threaded rod. I know you can order it from them I saw some stainless rod in there today............Mike

[Bob Hutchinson]

Jason,

Looks really great.....did you buy the vcarve software...i cant believe how fast it cuts stuff out.....my small signs take more time to lock down that to carve.....i finally got some paint mask and am going to try it tomorrow......will post painted stuff over the weekend ont the other thread.

Grizzmo