Steel Guitar Builder

a new keyless tuner im working on, thought someone might like to see it , comments welcome. Russ

Russ,I'm gonna follow the progression of this one! Maybe I'll learn a thing or 2 about milling procedures.
Question: How do you hollow out the stock? Plunge cutting or side milling?
I feel I am having too many vibration problems on side cutting. No matter what I try for rpm, feed rate depth of cut etc...I can't seem to find the ideal everything.
What size its that end mill? Looks like 1"

Hi Bent , that end mill is 1/2 inch.Ive watch your progress and your doing really good , you have milled some very nice pieces. As far as plunge cutting goes , id never do that myself , what i d rather do is follow along just inside my finished marks takeing cuts all around the area i want removed gradually going deeper every time i make a new pass untill i get close to the finish depth (or size), then takeing cuts 5 thousands or less to finish up all the way to my finish marks, side milling should very light as far as milling goes the less you mill the better the finish .Going around and around might take up more time but it eliminates chadder and vibration as well as a wavy finish . Keep your end mills sharp. I think was cutting at 2 3/4 inch pm useing the auto feed on my long cuts and by hand on the short cuts stopping just short of my finish marks then back around and cutting the inside out then back to the beginning then doing it again and again.Thats the way i do it Bent ,hoggin out .I hope this can help you , you keep at it your doing very well . Russ

Russ, Plunge cutting works best for me at the moment. I have tried side milling but there is just too much vibration and I have to take such small cuts so it is just too slow. My machinist buddy showed me how to plunge cut the safe way. This mill handles a 1" endmill which is excellent for plunging. But he also showed me side milling ...did about a 1/4" cut in a 1" thick piece and it cut like butter. I have not been able to replicate that combination of ideal feed rate/rpm. I guess I am too timid. Just have to keep trying I guess.

Bent,
Plunge/hog milling, as you describe in your other post is the way to go. I would suggest getting a set of bed clamps, Harbor has them reasonable. Also you can make a 30 deg fly cutter that (with a properly ground tool) works really good on wide flat surfaces. On aluminum, if you set the flycutter so the back side makes a cut that looks like fine hair when it follows, (see video)there will be a minimum of prep for polishing...... BTW your last project was over the top!!!!!!!!


Bill

Like the pic, except the body needs to be at least 2" dia, (so you can extend the tool to get a 3" cut.) and angle no more than 30deg with a well rounded tool. I can send you a print of one that I made if you like.

http://www.youtube.com/watch?v=FMNkPCtk ... =endscreen

Bill, pics and drawings from you are welcome any time. I still have the best rod bender in the world, courtesy BIFF.

I have been wondering if I should try a fly cutter. But seeing as I already have a 3" face mill, I don't know if the fly cutter would do a better job than this one. You can see the one insert. I only use one insert on the recommendation from my engineer buddy. That's what he and his shop had come up with as the best for aluminum.
I take up to 1/32" in one pass, with the finishing pass set to .005 deep at 14- 1800 RPM and feed rate of 8" a minute and lots of coolant/lube.
Still, the finished end plate has minute marks and is ready for a quick sanding with 180 grit followed by 220 etc etc. up to 600 grit. I thought it were possible to get a finish off the mill to start buffing. What do you say?

Bent,
Sounds like you have it covered, the insert system is good but, as always DIY/free is good also. If your cutter has even number of inserts, use two @ 180deg, and tilt so the trailing insert is cutting to look like hair(or, just tilt with one insert). Look at the video, and you will see what I'm talking about. Give me a couple days, and I will try to find my print, or draw another.

Bill

Bent...edited to say...On your last pass with the 3" index mill, if you can spare another couple thousands, just reverse the feed, and do a reverse pass without changing the depth of cut, or try on a piece before you get to your desired size.

http://www.youtube.com/watch?v=lepvntEd3Jk

Russ,

How is this coming along? I'm really interested to see how this works out. You may even have finished it by now...

Will C
Huntingdon UK