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wrightracing.net
03-22-2007, 09:15 PM
This is my first post and I am new to Mils and Lathes.

I am a weld/fabricator of Off Road Race trucks and Buggys and I am trying to speed up the job of notching tubing for roll cages. Until now I have been grinding the notch or a hole saw was used.

I want to find a end mill holder that bolts to the mounting plate of a lathe.
I tryed to use a 3 jaw chuck to hold the end mill and it held for a little bit but the jaws can not hold the 1.24" shank well enough to notch tubing.

The Mill/Lathe I have is a Cetral Machinery combo with a 4.25" mounting plate and a 1.560 bore that threads onto the lathe.

One idea I have if I can't find a premade tool holder is to get some 4.25" bar stock and bore out the center to 1.25", Drill and tap a set screw and drill and tap mounting bolt holes on the back so it would mount to the Lathe mounting plate.

I would rather buy one already made but I just wanted to hear from people with experience in this area.

David Wright
http://www.wrightracing.net
rookie-wantabe mechinist

Fasttrack
03-22-2007, 09:39 PM
Any reason not to hold it in your mill?? You can get end mill holders, even MT3 endmill holders that will accept large shank endmills.

Otherwise, you could take a short piece of hexagon stock, say 2.25" in diameter and bore your hole for the endmill with a set screw. It would save you some time and hastle making the mounting holes and should be alot cheaper. The hexagon stock could be held in the three jaw and would not slip since it has three flat surfaces for the chuck to grab. Thats the quick and dirty...

Should be nice and easy; just cut you off a length of the stock, hold it in the chuck, face it, and bore a hole in it. Drill and tap your set screw and your done.

<edit>
Note that it won't be super accurate, you have some runout drilling your hole with the three jaw and then that runout is compounded when you take out the adapter and put it back in. It should be fine for notching tubing, but not great for precision stuff.

and you might wait to here from some of the more expierenced guys to chip in thier wealth of knowledge.

mochinist
03-22-2007, 09:39 PM
I would think your idea would work, but I have never done any milling in the lathe. Cool site you have there, I grew up around offroad racing in Parker Az always wanted to get into it, but the kids I had ate into my racing fund.:o

BadDog
03-22-2007, 10:57 PM
Buy or make a Weldon style EM holder with straight shank. Cut (if soft enough, maybe carbide?) or grind flats on 3 sides at 120*. Now you have a positive lock on the EM, and 3 flats to positively lock in the 3 jaw chuck.

That or do as suggested, just get an R8 or straight shank Weldon holder to mount it in your mill...

Joel
03-22-2007, 10:58 PM
Use a hex collet block, hex stock, or any variety of ways to put 3 flats on the chucking end of the holder (would have to be 1 1/8" or less if using a collet block). Number one of the flats and one of the jaws so that they are indexed. The resulting runout should be fine for your purpose.

J. Randall
03-23-2007, 12:18 AM
Another thing thats not been mentioned, if your lathe has a taper in the front of the spindle( a lot of lathes use a morse taper), get or make an endmill holder with the taper needed and drawbar it in to the spindle. You can do this with a home made drawbar or even allthread and large washers on the outboard end.
James

Rex
03-23-2007, 11:07 AM
I'd go with Fasttrack's suggestion and bore a piece of hex stock, if you can find it in a big enough size. Mark which hex goes to the #1 jaw (they should be numbered) and put your setscrew in that face. Then everytime you use it, align the setscrew with #1 jaw and you should be concentric.

If you don't do that, your original idea of bolting barstock to the faceplate and boring your hole would work fine. If possible, I'd want to dedicate that faceplate to this task so you won't have to break it down and lose the concentricity.

There's a nice commercial jig to do just what you are shooting for:

http://www.torchmate.com/tubenoch.html

Note that it uses hole saws, but the tubing holder is basically a milling attachment grooved to hold tubing.

By the way, check out their power tailstock feed. May have to make one.

pcarpenter
03-23-2007, 11:28 AM
I know I may often sound like a pessimist, but it comes from a personality type that makes me always re-examine the root problem with relation to the end solution, first.

You can get R-8 end mill holders that will hold a 1.25" end mill. You can buy the cheapies for around $15 and I would be tempted to buy one as the start for anything else you do as it should be nice and concentric.

On the other hand, I would first look at whether this is a good solution. I would think that milling the end of a tube would be less than ideal and probably not the fastest solution. Tubing notchers that use a hole saw are most common for this sort of thing and should produce better results on thin material (like tubing) than would a 2 or 4 flute end mill. In general, you want several teeth in the work at all times to avoid chatter in cutting. This is the reason you use a finer blade on a band saw for cutting thin stuff, for example. The type of cutter that provides this in this sort of application is a hole saw.

Were you having problems with using the hole saw? If so, were you using one of the tubing notching fixtures that holds your work well? They are available cheap from Harbor Freight and other sources. You may want to fabricate one, too. I recall that there was an article on making one in either HSM or MW some time back (maybe years?) but it should not be hard to fabricate one on your own.

Paul

wrightracing.net
03-23-2007, 06:58 PM
I know I may often sound like a pessimist, but it comes from a personality type that makes me always re-examine the root problem with relation to the end solution, first.

You can get R-8 end mill holders that will hold a 1.25" end mill. You can buy the cheapies for around $15 and I would be tempted to buy one as the start for anything else you do as it should be nice and concentric.

On the other hand, I would first look at whether this is a good solution. I would think that milling the end of a tube would be less than ideal and probably not the fastest solution. Tubing notchers that use a hole saw are most common for this sort of thing and should produce better results on thin material (like tubing) than would a 2 or 4 flute end mill. In general, you want several teeth in the work at all times to avoid chatter in cutting. This is the reason you use a finer blade on a band saw for cutting thin stuff, for example. The type of cutter that provides this in this sort of application is a hole saw.

Were you having problems with using the hole saw? If so, were you using one of the tubing notching fixtures that holds your work well? They are available cheap from Harbor Freight and other sources. You may want to fabricate one, too. I recall that there was an article on making one in either HSM or MW some time back (maybe years?) but it should not be hard to fabricate one on your own.

Paul


Hey Paul

First yes I have been using a Hole saw Fixture for a while. It works OK for 90deg notches, but it is a pain to notch 2"X.120 Dom tubing of length’s longer than 4 Feet. Also with tubing of this size the angle notches are a pain.

The best way to go is buy an end mill notcher but the cheapest one is $3400.

I just got a deal for a 1.75” end mill, 1.25 shank with 6 flutes and a 1.25 end mill holder. I am going to try it in the 3 jaw chuck.

I do not expect it to work without chatter, but we will see.

My plan is to bore a 1.25” hole in a 4.25” piece of Bar stock and turn down 2” of that and leave a 4.25” mount I can tap and mount to the spindle. Then I plan on drilling two set screw holes and tap them to hold the end mill.

Like I said I hoped someone had a product already made but I may have to make it myself.

I have notched some test tubing with the lathe and it only takes 4-5 minutes to do and angle notch where as if I had to cut and grinder it takes a lot longer. And the just stinks and jams when cutting and angle notch with big tubing. With the mill it works great the first time instead of cut fit, grind, fit grind fit.

dalee100
03-23-2007, 08:21 PM
Hi,

If I understand you correctly, what you want is something like this.

http://img.photobucket.com/albums/v602/dalee1002000/Pipe_Notcher_Housing_and_Die.gif


That's a pipe notcher. It can be used in a simple hydraulic press to notch the tubing you use.

HTH,
dalee

wrightracing.net
03-23-2007, 08:37 PM
Hi,

If I understand you correctly, what you want is something like this.

http://img.photobucket.com/albums/v602/dalee1002000/Pipe_Notcher_Housing_and_Die.gif


That's a pipe notcher. It can be used in a simple hydraulic press to notch the tubing you use.

HTH,
dalee

That works for tubing that meet at a 90deg but when you get to strange offset joints that will not work.
but here is what I would like to buy but can't afford at this point.
http://www.bii1.com/images/new/RMD/TN-800.jpg


I have the lathe I just need to hold the end mill correctly.

Fasttrack
03-23-2007, 09:31 PM
Hey Paul

First yes I have been using a Hole saw Fixture for a while. It works OK for 90deg notches, but it is a pain to notch 2"X.120 Dom tubing of length’s longer than 4 Feet. Also with tubing of this size the angle notches are a pain.

The best way to go is buy an end mill notcher but the cheapest one is $3400.

I just got a deal for a 1.75” end mill, 1.25 shank with 6 flutes and a 1.25 end mill holder. I am going to try it in the 3 jaw chuck.

I do not expect it to work without chatter, but we will see.

My plan is to bore a 1.25” hole in a 4.25” piece of Bar stock and turn down 2” of that and leave a 4.25” mount I can tap and mount to the spindle. Then I plan on drilling two set screw holes and tap them to hold the end mill.

Like I said I hoped someone had a product already made but I may have to make it myself.

I have notched some test tubing with the lathe and it only takes 4-5 minutes to do and angle notch where as if I had to cut and grinder it takes a lot longer. And the just stinks and jams when cutting and angle notch with big tubing. With the mill it works great the first time instead of cut fit, grind, fit grind fit.




If thats what your set on, go for it. I still think time wise and setup wise it would be alot faster just to make a little holder out of hexagon stock, or mill three flats on a holder you do have to hold in the three jaw. But if hexagon stock isn't readily available or you just want to give it a go, have fun!! Thats what i think is so cool, most of the time you can dream something up and then actually build it.

Sometimes, more often in my case, our skills fall short... :( :D

mochinist
03-23-2007, 11:37 PM
That works for tubing that meet at a 90deg but when you get to strange offset joints that will not work.
but here is what I would like to buy but can't afford at this point.
http://www.bii1.com/images/new/RMD/TN-800.jpg


I have the lathe I just need to hold the end mill correctly.That looks like a pretty simple machine to make

wrightracing.net
04-05-2007, 11:56 PM
I got it working!!!

I had some problems with the vise I had but I got a bigger one and did some fine tuning of the riser.

http://www.wrightracing.net/other/notcher3.jpg

http://www.wrightracing.net/other/notcher2.jpg


http://www.wrightracing.net/other/notcher1.jpg

comerrm
04-06-2007, 12:08 AM
That looks like it would work pretty slick. For the Formula SAE cars we build up at school we often use a holesaw in the mill, but even with the finest tooth blade it manages to tear off teeth especially in .035 wall chrome moly tubing. Other times we use the roughing endmills like you are. I would like to try it in the mill, but the only problem for us is the fact that it would be hard to get compound angles on a conventional lathe.
-Rob Comer

Swarf&Sparks
04-06-2007, 12:15 AM
My BIL is in the stainless fab business (yachts mainly).
His notcher is a sorta belt sander setup.
You use different dia nose rollers to suit the required notch size.
Extremely fast and precise but it cost him $$$$.
Shouldn't be hard for the HSM to build/adapt something though.

BadDog
04-06-2007, 12:46 AM
The belt sander notchers do work VERY well. One of my "to do" projects is a KMG style grinder with interchangeable rollers for just that purpose...

wrightracing.net
04-06-2007, 02:12 AM
I have a friend with a belt sander he uses for notching and they do turn out great. But the belt sander cost over $3000 for the big ones that have enough HP. I got a 3/4 Hp one and it is to slow and stops if I push it to much.

That is why I went with the end mill. I got the mill/lathe for $400, the 1.25" end mill holder with a 1.75" end mill for, $20 on Ebay, a 2" cobalt 6" LOC end mill for $50 and a good 4" vise for $80. So $550 is a great way to notch tubing and I can do other things than just notching.

BadDog
04-06-2007, 02:53 AM
Yeah, it takes a significant grinder to do notching and other heavy/rapid material removal work. I have a 2 hp Baldor 3 phase motor setting among the other accumulated parts for the project. If I manage to bog that grinder down, something is VERY wrong and sure to be broken and/or flying across the shop shortly. :D

A.K. Boomer
04-06-2007, 03:07 AM
Looks good to me, I would rather use a cutter for something to be welded --- I think the sander impregnates the steel with grinding grit and am no expert but believe it to be a factor for a contaminated weld regaurdless of how much pre-cleaning is done.

BadDog
04-06-2007, 03:41 AM
I gotta disagree on that. I've used grinders, both stone and belt, on so many welds over the years that I can't begin to count. I will state without hesitation that for normal welding processes in steel, sanding belt or grinding wheel grit is not a factor. Perhaps for GTAW in nuke bound xray tested welds, maybe you might find something, but I seriously doubt it. And I would expect it to be FAR more likely for stone ground/fitted joints than belt finished joints. I routinely use either or both stone/belt to prep for welds and there is no discernable difference. I also come from a family of pipe fitters (who worked nukes), boiler makers, and ship builders who also never commented on it's use. These are the men who taught me pretty much everything I know about welding and fabrication, and they never mentioned it even when working with me and using belts and stones for that purpose. I'll also state that if it causes problems, I'm in a heap of trouble since every single piece in my rock crawler buggy's rear 4 link suspension was cleaned, dressed and fitted almost exclusively on a belt sander. That is a VERY high stress weldment and has welds as nice as any I've ever put down. I'm no expert and my evidence is purely anecdotal, but I have no reason to believe otherwise.

BadDog
04-06-2007, 03:46 AM
Also, if you don't use grinding, how do you bevel edges for welding? Or fit multiply constrained pieces of a weldment? This is paricularly important for the most sensitive of common welding processes, GTAW, which needs a VERY close fit. I can't imagine trying to fit any but the most trivial joint for GTAW (or O/A) without using a grinder.

Your Old Dog
04-06-2007, 08:10 AM
One of the belt grinder companies has a movie clip that shows just how easy it is to use their belt grinder to do the fishmouth. It has the added advantage of needing to be clamped to increase speed. You just set the miter on the rest and hold the tube up against it.

Looks like you have found a workable solution for prototype work but the belt grinder method just has to be much faster. 60 grit would cut that tubing like butter and give you a nicer finish.

edited to add:
I found the demo. Would be a great machine for fab work. http://www.youtube.com/watch?v=BYllaxuzMk0 My guess is he's using 60 grit here in the demo. Note that these belts about 2x72 and cost about $3.00 each and last really well. It's what Knife makers use to make custom knives out of exotic metals.

Carld
04-06-2007, 10:07 AM
wrightracing, I like your setup. That's very creative and very much like the machine you posted a photo of. Machine work is only limited by the creative imagination of your mind. Good machinists have creative minds to solve problems.

wrightracing.net
04-06-2007, 04:56 PM
One thing I noticed with that sander video is that it blued the steel tubing a little. I do know that on my freinds sander it did not blue the metal but he uses 30 grit to remove metal faster and not heat up the tuding. With the mill it does not blue the tubing so that is a plus. It does take about 2-3 minutes to notch a 45deg in 2"x.120 tubing. That is compared to 15-20 minutes to grind and fit, grind and fit and fit again.

The problem with blued metal is it could cause a weak welding surface do to the metal being heated and made weak.

Rex
04-06-2007, 06:24 PM
[COLOR=#0000ff][COLOR=blue][FONT=Arial]
I just got a deal for a 1.75” end mill, 1.25 shank with 6 flutes and a 1.25 end mill holder. I am going to try it in the 3 jaw chuck.

I'm sure you've tried this by now.
I'm betting that 3-jaw chuck turned loose of that endmill!

That's asking a lot from a 3-jaw chuck.
You really need a positive way of gripping that thing.

JCHannum
04-06-2007, 07:05 PM
It looks good to me. It will be faster and more accurate than a belt grinder, and it provides a lathe for other operations. I am not a big fan of the 3 in 1 machines, but for 1/6 of the investment of a belt sander, he has a machine that will have many other uses.

Pullout of the end mill will not present a problem with that setup as it is only milling thinwall tubing. Using the live center adds further support.

wrightracing.net
04-06-2007, 07:28 PM
The 3 jaw chuck has worked great so far. The shank of the end mill hoder goes into the bore of the chuck. Yes the live center stops it from chatter and pull out. At first I did not have the live center on the end mill and I had some major chatter problems. The LOC of the end mill is 6" and OTL is 8". The big vise and live center almost got rid of all chatter but a little bit is still there if I feed the tubing to fast. The thickest tubing I will notch is .120" maybe .250" but not that often.


Does anyone know where I can get these end mills cheap.

The person I got this one from does not have them anymore.

NIAGARA 2" DIA 1 1/4" SHANK 6" LOC 8 FLUTE NON CENTER CUTTING ROUGHING END MILL COBALT EDP # 45495

http://i22.ebayimg.com/07/i/000/7f/c8/6089_1.JPG

One thing I like about this end mill is thatit has a place to put the live center on the end of the tool. It is like they were reading my mind.

BadDog
04-06-2007, 07:41 PM
Does anyone know where I can get these end mills cheap.

Hehe. Ha ha ha ho ho. That's funny... ;)

And the need to have these in various sizes and the related expense is exactly what put me off of going this route. And frankly, for all the notching I do, the typical hole saw works fully well enough, at least until I get the belt grinder done. And speaking of speed, have you guys ever seen a belt grinder with coarse belt at work? I saw a video of one built specifically for this type of work in a custom fab shop. With 2" x 0.125" tube (IIRC), it looked like you were feeding an oak 2x4 through a table saw. Full notch at about 45*, start to finish, I would guess NO more than 5 seconds (which is longer than I recall, just playing it safe to not exaggerate). I seem to recall that one was about 5 hp? Maybe 3, not sure, it's been a few years...

wrightracing.net
04-06-2007, 07:51 PM
Hehe. Ha ha ha ho ho. That's funny... ;)

That end mill only cost $50

It would be nice to find it under $100:D

I am building a Class 3 Bronco Roll cage right now and the notcher has made life so much better.

I have gotten two other end mills a 1.75 for $20 and a 1.25 for $20.

I need to get a 1" end mill and thats all I will need to do off road race cages.

jacampb2
04-06-2007, 08:44 PM
Check the local surplus machine tool dealers. A lot of them, even the ones who sell on ebay will not bother to put up their odd ball tooling if they dont think it will bring much cash. Local surplus place near me, actually takes most of their inserts, carbide, and tool steel stuff to the recycler for scrap. Carbide brings roughly $8 a pound around here, so the lack of hassel of not haveing to sort the crap, and mess around w/ 1 at a time on ebay for maybe a dollar more than scrap price; scrapping it looks pretty lucrative to a surplus dealers.

Later,
Jason

JCHannum
04-06-2007, 08:50 PM
I agree with that. I often end up with large end mills that have a corner knocked off the end or a ding on a flute. They end up being pitched. You might take a look for tool sharpening services in your area, they may have some larger cutters with good flutes but trashed ends that are not worth regrinding.

BadDog
04-06-2007, 09:05 PM
That end mill only cost $50

It would be nice to find it under $100:D

I am building a Class 3 Bronco Roll cage right now and the notcher has made life so much better.

I have gotten two other end mills a 1.75 for $20 and a 1.25 for $20.

I need to get a 1" end mill and thats all I will need to do off road race cages.
Nice prices, much better than I would have guessed. When I was sniffing around seems like the cheapest I found a long 1.75" corn cob (the main one I need for rock crawler tubing) was around $50 surplus, and that took a lot of looking and calling. But that was quite a while back, and I know my way around in those circles much better now, so maybe I could do better with less effort if I tried again. Haven't really thought about it since I'm generally only looking for Bridgeport class end mills...

In any case, nice work and good luck! And thanks for posting your results too!