The future of the "engine kit"

[stevehuckss396]

Steve, are you really running the spindle at 1000 RPM?

I will include this in the documentation but Mach3 does not have control of my spindle speed. Cutters are maxed out at 3500RPM and drills are about 1/3rd of that. You will have to override the mach controls to suit your taste.


If you guys would like I can put spindle speeds in and repost the code. How do you calculate a spindle speed for a specific size drill bit drilling at 5 IPM

 

[mu38&Bg#]

That's definitely something you have to work out in the code. If somebody ran it as is, it would likely break all the tools. Two or four flutes, HSS or carbide? The instructions don't specify, does it matter? Manually changing the code for speed and feed wouldn't be a big deal, but it could also be done with variables. This is the tricky part, some will know what to change, some won't.

All feeds should be based on feed per tooth, including drills. Surface speed will be limited by spindle speed in virtually all cases. This means you have know spindle speed to set feed rate.

Greg

 

[stevehuckss396]

Cant that be reversed engineered. If I know cutter size and feed rate can't the spindle speed be calculated?

Spindle speed on most small mills is 3500-4000 max

 

[stevehuckss396]

That's definitely something you have to work out in the code. If somebody ran it as is, it would likely break all the tools. Two or four flutes, HSS or carbide? The instructions don't specify, does it matter? Manually changing the code for speed and feed wouldn't be a big deal, but it could also be done with variables. This is the tricky part, some will know what to change, some won't.

All feeds should be based on feed per tooth, including drills. Surface speed will be limited by spindle speed in virtually all cases. This means you have know spindle speed to set feed rate.

Greg

Most people set spindle speed manually and wont have any problem. I have to get "safe "numbers in the code for those who don't.

 

[mu38&Bg#]

The question is, can your customers do it? If not, you need to do it. Get my thinking? I looked at the code and when I saw S1000, the feed rates looked ridiculous. Who else noticed or even checked? Reading this thread, that is the major concern, setting feed and speed that works for any customer or teaching them to do it.

How do you do it now? I calculate for every tool/material I use. It's simple math. Any major brand tooling supplier will have it in their catalog.

 

[stevehuckss396]

The question is, can your customers do it? If not, you need to do it. Get my thinking? I looked at the code and when I saw S1000, the feed rates looked ridiculous. Who else noticed or even checked? Reading this thread, that is the major concern, setting feed and speed that works for any customer or teaching them to do it.

How do you do it now? I calculate for every tool/material I use. It's simple math. Any major brand tooling supplier will have it in their catalog.

I plan to do it. Up til now I manually adjusted my spindle speed for the feeds that I put in the code. That is what most people "have to do" in the hobby word. If i move forward with this I need to learn to calculate these things. Where do I find this simple math?

 

[Scott_M]

I use HSMadvisor, it used to be a free download and is also available online here http://zero-divide.net/?page=fswizard oh here it is, if you want it as a download. http://hsmadvisor.com/index.php?page=Download

It works very well , and for drills too, it also has a rather extensive "material" list.

Scott

 

[stevehuckss396]

OK Everybody Stop!

I have overlooked a very important aspect of the code. I set my spindle speed manually with a speed controller. It's not something I have ever had to do and it is something that must be done. I'm asking everybody who does not have manual control of your spindle not to run the code until I get this situation taken care of.

Thanks! & Sorry!

 

[stevehuckss396]

I just downloaded a calculator and I found out that at the depth of cut and other things considered, i am dam close with my feeds. The problem here is i never setup the spindle speed in the cam because I just dont ever do it and it was overlooked. According to this calculator I should be at 24.40 IPM with the 1/8 inch cutter at the depth of cut im taking. I was set for 25.00. I checked a few cutter sizes and they were all in the ball park.

Were good. Let me post new code for the guys who have mach set the spindle. If you do it manually drill at 2500 and mill at 4000 RPM

Carbide end mills
HSS drills

 

[kjk]

I get those numbers for a 4 flute carbide cutter. Halve that for 2 flutes. That's for roughing - halve again for finish cuts.

 

[aonemarine]

Since were on the speed and feed thing, i have a question for everyone who has a cnc mill and would be considering running other people's codes.
Whats your max spindle rpms?
Unfortunately my g0704 is limited to 2300 rpms. Maybe it would be best to limit the feed rate to whatever the slowest mills can handle by thier rpms? Doesnt matter much to me, i manually set my spindle speed and would just set the feedrate in mach3.

 

[stevehuckss396]

Since were on the speed and feed thing, i have a question for everyone who has a cnc mill and would be considering running other people's codes.
Whats your max spindle rpms?
Unfortunately my g0704 is limited to 2300 rpms. Maybe it would be best to limit the feed rate to whatever the slowest mills can handle by thier rpms? Doesnt matter much to me, i manually set my spindle speed and would just set the feedrate in mach3.

If I were in your shoes I would just override your feed rate down to about 60 percent

 

[aonemarine]

If I were in your shoes I would just override your feed rate down to about 60 percent

Yes, thats what i meant i would be doing.

 

[stevehuckss396]

OK heres whats going on. I have tried a few of the calculators and my feed rates were not out of line. The problem I had was I did not set a spindle speed so anybody that has the spindle speed set automatically would have been set to slow. Other than that, unless you see anything I missed, here are the new files with the spindle speeds. Guys with spindles that cannot achive 3500RPM will have to lower there feed rates accordingly.

Thanks for your patience. It's real hard to think of everything so things will improve as time goes on.

View attachment CylinderHeadInstructions.pdf

View attachment Step1HeadTop.doc

View attachment Step2HeadFixture.doc

View attachment Step3HeadBottom2D.doc

View attachment Step4HeadBottom3D.doc

 

[Buchanan]

I have been giving this a try. Every thing works fine so far except I did not have Mach 3 set to stop for a tool change. You might want to mention that in your instructions.

I have the basic shape of the head finished,and am starting the fins.

The basic concept is awesome. Far better than trying to fit dimensions into a casting.A waster is not a disaster and the fun part of machining starts immediately. I find the drawing/ G code part is still daunting.

Please don't stop now.

Buchanan

 

[stevehuckss396]

I have been giving this a try.

Buchanan

So how did it go so far? Other than the tool change did you hit any snags?

 

[kjk]

Steve: Looks fine. I note that the sizes of the #28 and #32 drills are both annotated as being 0.116 rather than 0.116 and 0.1405.

I'll run the part as soon as I can put my hands on some 1/16 carbide endmills.

 

[michael-au]

I run the code today, being new to cnc and a bit nerves, i for got to lower the feed speeds in mach3
The holes drilled fine and the tool change was ok ( a bit more on this latter) then I had to change to the 1/8th milling cutter, this is where the feed became to fast
The spindle cam down to fast and hit the top of the stock just hard enough to make the stepper loose its place, I hit the stop button in mach3
I then realised I forgot to lower the speed
So I set the speed over ride down to 25% and because the X,Y axis was still in the right place I reset the Z o 0 on top of stock and set mach3 to run from the 1/8 tool change
This worked out ok, except that the stock must have moved down slightly when hit with the Z axis, anyway the program run with out any problems until i cam to the tool change for the 1/16, I don't have a 1/16 mill so I used a 2mm instead , next problem the z came down and seem to go full depth of the cutter and it broke (bummer)

All tools were set to the same length so that end of tool would be 0 on top of stock

It seems to me that on the tool change the Z wants to move up around 3.5 inches, not sure if thats been set in the code, I assume it is

So I am wondering if the z height for the tool change can be set at around 1 or 1.5 inches, not sure if it is posible to do this in mach3 or it can only be done in the code before post processing

It was a good learning curve regardless of breaking a new cutter (lucky it was a cheap chines one)

Will give it another go when I get a new milling cutter

This was as far as I got, time to go to work will try again

 

[stevehuckss396]

Z height should be set every time a new tool is put in.

When a tool change occurs, the tool pops up to the clearance height of. 125 or. 250 depending on which program you have loaded. You should then have to raise the tool to a comfortable height manually.

 

[michael-au]

It's all a learning curve, I will try a gain and make double sure the set up is right

This could be the first dumb question: is it right that on the tool change the mill goes to the home switches?
And the waits for the cycle start to be pressed
So before pressing the cycle start I can move the piece back under the spindle and then reset the z and then press cycle start from there?

I'm leaning toward something I did wrong when I set it up

Thank you for make the code available for us to try, I have drawn parts in mastercam and machined the parts, but I have never had tool changes it the code, just used the same cutter for the whole job

Anyway thank you again

Michael