leegscott

H-M Supporter - Diamond Member
H-M Lifetime Diamond Member
Joined
Mar 2, 2021
Messages
26
I am so glad I found you guys this morning. I have been watching you tube videos for the past 6 months trying to decide on which mill to purchase. The general advice that I have been given is buy as large as I can afford. I have also been told that regardless if I purchase a new one (import) or a used one there will be things that I will need to adjust or correct. However, at least with a new mill, parts will be easier to find. As of last week I was down to two, the Grizzly G0755 & G0731. However; it was recently suggested that I consider the PM-940V mill. Wow, it does look good to me and there are quite a few videos of them being converted to CNC capabilities which is what I would want to do - so there are footsteps I can follow and hopefully some of you will be willing to coach me along the way.

My primary hobby is experimental rocketry. I am needing to machine aluminum parts as well as I would like to be able to machine composite parts from composite plates that I make.

If anyone has any advice on the mill PM-940V or might have another suggestion, please share it with me. I know that it has been done before but I will post pictures and a video of the build. I will continue going through the you tube videos as well as this forum (a lot of info to sort through) for upgrades that I should consider when I have the mill apart.

I plan to call Precision Mathews this month and get it ordered.

Thanks again and I am excited I found you! There is a huge amount of knowledge on your forum which I recognize the value as well as the time that has been put into it.

Lee
 
One idea if you are definitely going to go CNC is to see if there is one with a full CNC conversion kit available. Then buy the kit, install it and you are done. Otherwise you will need to source parts and figure out how to get it altogether.

Maybe search CNC conversion kit for mill and see what comes up. There may be one for the PM machine you want too.

Would be nice to know before you bought something that would be a major project to convert to CNC.
 
Hi Lee,

Honest, I am NOT trying to make your machine decision any more difficult.
But I have a few thoughts.

I dunno about "as large as you can afford"......I do subscribe to "as large as you need for your largest part or project"

Much of rocketry stuff is cylindrical (nose cones, engine nozzles, etc.) have you thought about a lathe?

Welcome to the group!

-brino
 
Welcome! Always nice to see another rocketry nut around here. I know some of the PM mills have CNC conversion kits available, and some others that have done it. I have a PM lathe and I've been very happy with it.
 
Welcome Lee. I don’t have a PM mill but like others above, I have a PM Lathe and have been very happy with it. I have a Jet mill drill and if I had found PM before buying it, I would have preferred a PM mill. Will likely upgrade to one at some point. Like Brino, I am curious if you need a lathe for all the round parts on your rockets? What projects are lined up for the mill? Space is also a consideration when picking the machine. Largest you can afford is OK, but consider the space, what other equipment you will need to add etc. Space gets used up fast.
 
Guys thank you so much for the responses! I do have access to a lathe and have used it a few times. I am planning on purchasing one at some point but my current bigger need is a mill.

I am wanting to machine rocket fins out of both aluminum and composites. I believe the maximum dimensions of the fins will be 9” in the y axis and 18” in the x axis (mill terms). I am hoping that I can machine them in a circular arc airfoil or a double wedge from the leading edge to trailing edge with an option to taper from root to tip (all rocket terms). I believe that both of these shapes will be difficult to machine which is why I am planning on spending the money for CNC which appears to be as expensive as the lathe.

Now if you guys think I can possibly do it with a smaller mill that would be great!!! I was planning to look at the y travels tonight of the smaller mills.

Again I am so glad I found you guys!

lee
 
I mentioned lathe when describing price of cnc for lathe I meant to say mill but I think the dollars would apply to both. You never can have enough room in the shop. If you guys think it would be close with a smaller mill, I would be willing to take that chance to be able to invest more in the cnc
 
Sounds like you have done some research and have a plan. 9x18” is a good size piece. You should be able to find the best PM mill for the job, and likely one of the larger ones. Sounds like a lot of fun. I only used CNC during my apprenticeship many years ago so don’t know much about that other than videos I see. Very cool indeed. Enjoy!
 
Even if the largest part you now have need for will fit a smaller mill that doesn't mean you won't want to make a larger part next year! I mostly do repair work so I've pushed the limits of the part sizes my machines can handle. My 9x49 Jet knee mill only has an X travel of just over 30", i don't remember exactly what it is. Y travel can be increased by sliding the ram out and ending up with quite a lot. Z travel is the most likely to be run out of, for me. Especially for boring
 
I plan to call Precision Mathews this month and get it ordered.
.......oh one more thing, and I am still not trying to be a downer.....

From what I have read here, you should set your expectations that there will likely be some delays, just like everything else these days.
Not sure if it's the unloading delays and container ship backups in California or what.

Please let us know where it leads.
Good Luck!

-brino
 
Back
Top