[John Bear Ross]

Just wanted to show off my spindle upgrade. I had bought a Bosch Colt palm router about the same time I bought my Taig from Nick Carter. I tried to make an erzatz mounting bracket for it, but didn't really like the results. I also didn't like being limited to 1/4 shank tooling. I shelved the project, and learned to cut with the conventional ER-16 spindle.

Still, I wanted something more in the performance department from my mill. So I looked around, saw that K2 sold a bracket for the Colt, and ordered it. Simultaneously, I found a source for precision collets and a closer nut from precisebits.com. I ordered the parts, fabbed up a mounting plate for the bracket, and here are the results. A Taig CNC mill with a 1 HP spindle, capable of up to 35K rpm. We'll see how the bearings hold up to extended duty, as my tool paths can take hours, if not days, though the Bosch is reputed to be quite solid.

And if I need to switch back, it's only a matter of 4 10-32 bolts.

Here's the pics...








Best,
John Bear Ross

[fretsman]

Interesting, John as I considered doing this same exact thing at one point.

Unfortunately I saw the inconsistencies in the Bosch Colt laminate trimmers as I own one and the runout is just too great for the work I do.
http://www.precisebits.com/lab_repor...h_colt_TIR.htm

How much runout are you getting and, if you don't mind me asking, what kind of work to you do? What's the smallest cutter you use?

Thanks for sharing-
Dave

[ger21]

Dave, that link you posted says they've only seen two Colts that have not worked with their precision collets.

[fretsman]

Dave, that link you posted says they've only seen two Colts that have not worked with their precision collets.

Hi Gerry, yes but that's what "they" have found

And mine would be a 3rd-

Dave

[jemmyell]

Hi Gerry, yes but that's what "they" have found

And mine would be a 3rd-

Dave

Have you measured the runout on your Colt without the standard Bosch collet and nut? Was it new when you got it? Any play in the bearings?

-James

[fretsman]

Have you measured the runout on your Colt without the standard Bosch collet and nut? Was it new when you got it? Any play in the bearings?

-James

Hi James,

Don't get me wrong, I love the colt by bosch as I use it for numerous other jobs, but it's just not near as accurate as my taig spindle. I do small engravings and I just can't afford to have any runout at all but I would love to have the versatility of the Laminate trimmer speeds and the mounting.

The colt taper is not "true" as the runout is indeed .003-.004" with a bit installed and to purchase the precisebits.com collets and nut would be useless at this point or at least a crap-shoot (for me!). I think that's why they (precisebits.com) say to try and buy the collets first and THEN go buy a colt and try the collet in the spindle to check for slop. Well that's going to be a needle in a haystack kind of thing and I'm sure the store would just love the customer opening up all the boxes just to find a good one, lol!

This is why I asked John, to see what his runout was and what kind of work he was doing. Not trying to stir anything up here at all.

Thanks,
Dave

EDIT: Yes the colt was indeed new and no, no play in the bearings.

[noisillator]

John, that mounting plate looks really nice. Did you fab it on the Taig? Also, what material(s) would you cut with a laminate trimmer at 35K that the 10K standard mill doesn't do so well?

[John Bear Ross]

Not to worry, Dave.

I'm doing sci fi models in wax and delrin, maybe epoxy, too. Nothing too high-tolerance. I'll check the runout with a dial indicator tonight.

Best,
JBR

[John Bear Ross]

John, that mounting plate looks really nice. Did you fab it on the Taig? Also, what material(s) would you cut with a laminate trimmer at 35K that the 10K standard mill doesn't do so well?

noisillator,

I did fab it on the Taig. If the spindle head knew it was assisting in creating its replacement/supplement, I'm sure it would have gone on strike. Heh.

I'm really on a quest to reduce my tooling marks, more than anything. Surface finish is pretty important to my clientele, and even the tiny milling marks of a 10K rpm cut at 5 ipm brings questions of "can that be buffed off?" I'm just trying to avoid that. I work mostly in wax and delrin, sometimes epoxy, too.

Best,
JBR

[TDA]

The colt taper is not "true" as the runout is indeed .003-.004" with a bit installed and to purchase the precisebits.com collets and nut would be useless at this point or at least a crap-shoot (for me!).

You have .004" runout? Would you mind telling me where you got it? We are trying to narrow this down since it is the vast minority of people that have had issues we think it might be from a single source that these are coming from.

I think that's why they (precisebits.com) say to try and buy the collets first and THEN go buy a colt and try the collet in the spindle to check for slop.

I don't want to say where the 2 we know of came from (you can imagine why) but I don't know of anyone so far that has got one from a retail store that has had a problem.



One last thing if you do ever want to try them and they don't work for you you are alway free to return them per our standard policy:

At PreciseBits our goal is 100% satisfaction. We believe in our products and are willing to stand behind them.

If you are not satisfied with the tools that you have received, for any reason, you can return any of our products back to us, in the original packaging, within 30 days of the invoice date, and we will refund your money*. All you have to pay for is the shipping and for any tools you do not return. It is as simple as that.

We have built our reputation on quality products and services that are delivered in a timely and cost effective manner. That's not going to change.


Ron Reed
President

Inevitable fine print:

* If your payment was made with a credit card or PayPal, the 3% non-refundable processing fee that is charged to us by the credit card company will be deducted from your refund. Carbide bits that have been used in any way will not be covered by this warranty, so please do not return dull or broken tools.

[Jeff-Birt]

This is an interesting idea for a Taig. For certain types of work it should do a good job. Given that the spindle speed only goes down to 15k it would not be good for use with machining steel. For use on wood, wax, PCBs, and aluminum (with smaller cutters) it would work fine.

[John Bear Ross]

Mr. John Torrez,

I sent a memo via the website, asking for a 3/16th collet to be made in the future for my new Colt rig, so I can use my tooling with that shank diameter. Any chances of that happening?

Best,
JBR

[Jeff-Birt]

This discussion is in the TAIG section of the forum, and my comments were aimed towards the applicability of using the Bosh Colt with a TAIG mill. The TAIG cannot do high speed machining as I guess was the point in the PDF you attached. The Taig is not rigid enough nor is a Bosh colt powerful enough.

Please refer to a good feed/speed reference for various steels and you will see my point. You won't be cutting steel with a 3/8 end-mill at 15K RPM on a TAIG.

Bosch specs the speed rang of the router motor from 15K to 35K as that is the range where the motor can generate usable power. So for certain types of work the spindle speed would work great for other work it is not appropriate.

[fretsman]

Hi John,

You have .004" runout? Would you mind telling me where you got it? We are trying to narrow this down since it is the vast minority of people that have had issues we think it might be from a single source that these are coming from.

I don't want to say where the 2 we know of came from (you can imagine why) but I don't know of anyone so far that has got one from a retail store that has had a problem.

Well I'm not sure it would be fair to say who it is just as you would prefer to keep your info quiet. Let's just say it's a major retail chain store.

One last thing if you do ever want to try them and they don't work for you you are alway free to return them per our standard policy:

I understand that and that's why I posted the link for all to see. Not trying to ruin anyone's credibility here, just wanted to get John's (Bear Ross) feedback that's all. It would be fantastic to have a retail store that would be willing to do that, I just don't think it's going to happen that way. It may benefit you, since you've only found 2 (and now 3) that maybe you could look into purchasing a batch of these that you know the runout is reasonable, and sell them right off your site as a package. I'll tell ya, if you did, I'd be first in line.

Thanks,
Dave

[jemmyell]

Hi Dave,

I also am not trying to be contentious, but the problem with the Bosch, Porter Cable and other routers has been found to be the STOCK COLLET / NUT combination. When you put a router bit into that and measure runout you are NOT measuring the actual capability of the router itself.

-James

[cameraguy]

I know that the donut guys comments were more to troll a fight than actually discuss anything rational, but I thought I'd put another point into the mix;

I do high speed machining of camera parts, often on steel, and with small enough bits (under 1/16") to require speeds that high. On paper it looks like it would work. It doesn't work in real life however.

You can't go over 5% of a bits diameter in runout without trashing it. Even that is pushing it. Runout of .001 won't bother a larger bit, but with small enough bits to require these high speeds it simply destroys the bits.
For bits small enough to require 20k+ RPM, the runout has to be in the tenths. Just not router territory.

Even if a routers runout was only .001 (and it usually isn't) it still won't work for high speed machining of steel as it can't handle tools small enough.

[Jeff-Birt]

Looking at the tools you found and the 0.020" DOC listed they are showing 90.55 IPM at 28.5K RPM. I don't think the Taig will be stiff enough to pull that off. Also as you move up in bit size if you figure out the actual HP required to make the cuts at the feeds/speeds suggested you'll find that it is more than the Colt can provide and would no doubt put more side load on the bearings than they were designed to handle.

Now, if making circuit boards were your thing you could feed about 35 IPM with the router motor at 35K and it would work great.

Thanks cameraguy! It is nice to see another source of real facts and good conversation.

[joeybagadonuts]

Jeff Birt,

Here is the high speed, high rpm cutting data you requested.

JoeyB

[cameraguy]

I have to chip in and say that Taig can indeed do 25k+ RPM machining of steel, but only with a stupidly expensive Japanese spindle costing significantly more than the Taig, and with a runout listed in nanometers.

A router just doesn't work, as much as I would have liked it to.


The bits themselves will snap with only a few ounces side pressure, they can't load the machine. When you get to tiny bits and that high speed, side loading isn't the limiting factor.
Either the chips are clearing or the bit just snaps. Rigidity isn't as big of a deal as you might think. Its all about runout, chip clearing, and damping oscillations.
Its just a completely different form of machining entirely.

[Mini Beast]

This is an interesting project, thanks for posting the pics. I like your clamping bracket, it looks very cool. Will those pockets in the clamp fill up with chips? I might have put tapped holes in the clamp, then countersinks on the mounting plate for screws to come in the other direction to fasten the parts.

Interesting stuff about high speed steel machining with small bits. It makes sense how runout would be the limiting factor in that style of milling. I definitely don't have the knowledge to add anything to the discussion, but I like the approach of just trying something and proving it works. The OP is definitely proving that this mod works really good for his type of application.