[harryn]

Hi - I have a reasonable amount of experience with common wood working tools, and just enough with metal cutting mills to be dangerous.

I am toying with buying a fully ready to go, off the shelf, 3925 with all of the rigidity upgrades and their recommended routers, etc. I mostly work with 7000 series Al, some wood, and some polycarbonate. This is for hobby use, not heavy use, but when it is running, I would like to be able to set it up and walk away while it makes several parts.

One of the parts I want to make includes 2 holes approx 20mm dia bored 200mm deep in 7000 series Al. I don't need perfection, but +/- 0.1mm would be nice for roundness and alignment of the holes through the piece.

Since the Z axis max is 8 in, I was wondering if there is a way to have a router mount which would allow the router to be boring horizontally instead of vertically ? This would make it sort of a horizontal boring machine for making these longer holes, which can be helpful for chip removal.

Drilling speed is not an issue, as this is a hobby / proto machine, not for production, but the drill holder must be large enough to hold the bit, which is slightly larger than 3/4 inch. I already have a bit like this which was used in my brothers manual vertical mill. (He lives 2000 miles away, so no, I am not considering upgrading his with cnc controls)

Any comments on the sense / non sense of this idea ?

[ger21]

I wouldn't think that machine is up to that task. 8" deep in aluminum? How long is the tool?

[RICHARD ZASTROW]

Sounds like a gundrill application. How many holes? 1 pc. or 1,000 pcs?

[harryn]

Hi, thanks for the note. I decided to also write an email note to the mfg for their opinion on the application. I will post the general answer if it is ok with them.

I am sure once I get the router, I will use it for many wood applications around the house as well. I use a hand held router now, and it works fine, but the operator has problems sometimes.

As far as Al machining, I use 7000 series because although it is hard, it machines very well, even without lubricants, and forms nice, small chips with conventional metal tools. I also like the hardness aspect.

The most common Al part I have in mind is actually quite a bit smaller. Sort of an oval approx 3 in high x 1 wide x 2 long with 2 each 1/2 in dia x 2 in deep. I would really like to be able to make 100 of these.

The 8 in deep part - probably more like 10 - 20 protos. If it ever got into production, I would have it extruded with the holes and just have the final shapes machined in. I know gun drilling would work, but at this stage, I really want to understand if this would be close enough for my hobby stuff.

The existing tooling is not really a big deal, as I can always get something else to drill the holes with. My brother did some machining for me using the maual mill, and we used a long custom drill bit that was approx 10 in long + some for the collet, and we also tried it with an end cutting mill. He has a bridgeport style manual mill and it is very accurate (when he uses it) but he lives 2,000 miles away, and is too busy to really do work for me quickly. Also, some of the shapes I want to build are difficult to do manually.

The end mill was nice in that it was a bit stiffer so it ran straighter than the drill bit, but he also had played with the end to modify it for better drilling. He was trained as a machinist, so he dabbles a lot with tooling. Sometimes, this part takes longer than the actual machining.

The long vertical holes were a pita when it came to chip removal. We made it work, but it made me appreciate the idea of horizontal boring.

I guess the cautions I should take here are:
- The routers max dia collet is probably 1/2 in ?
- The speed control is limited ?
- There would be a limit on how much metal removal could be done - I am hoping for at least 0.025 in per pass in rough cuts.
- The bearings might not be good for the side load milling / cutting / drilling Al ?

Thanks

Harry

[sploo]

I guess the cautions I should take here are:
- The routers max dia collet is probably 1/2 in ?
- The speed control is limited ?
- There would be a limit on how much metal removal could be done - I am hoping for at least 0.025 in per pass in rough cuts.
- The bearings might not be good for the side load milling / cutting / drilling Al ?

Thanks

Harry

Yes, I think most routers are limited to 1/2". The PC 892 comes with 1/2" and 1/4" collets.

The minimum rpm of the PC is 10k. I don't have any experience with metal cutting, but I'd suspect that's a little high.

There's a video on the K2 website showing them cutting 6061 AL. The details are: 0.25 Carbide End Mill, 0.050 Depth, 0.25 Cut width. So 0.025 sounds possible.

I can't comment on the bearings. They were using a Porter Cable router for the AL cuts, but I don't know how long it would last.

EDIT: Looking at the AL cutting videos, I don't think that is the Porter Cable router, but the text on the site claims it is.

[edmunds]

Hi Harryn!
We have made a solution with Atemag GMBh custom made angle head, suitable for drilling horizontally and also attaching sawblade on in. For producing a single custom made head it took 4.5000 EUR and four weeks for waiting.
I believe that in Your case the clutch joint with CNC spindle will be slightly customised and You can make the aggregate much shorter than we have.
My contact was [email protected].

B.R.
Edmunds

P.S. Has anyone dealed with Z origin sensor? Maybe someone know how it works?

[harryn]

Thanks for the information. 4500 Euros is a bit more than I had planned for an angled head. I guess I was thinking of just mounting the router on its side and drilling in that way.

I am still deciding on how to approach this project - K2 or home built.

[sehast5]

Harryn,
Did your ever get anywhere with the horizontal conversion idea you had? I have a KG3925 and would like to find a way to horizontally mount a router to better do various wood joints.

[9lrac9]

WOW... you guys have great ideas. Next think........................... what it's going cost to fixture the router motor and then the exotic fixturing for those 8" holes will the 3925 be enough. And the z will all be almost used up by the router itself. There is expensive high end motors out there you can adapt to the 3925 that has a 90 head on them around 3000.00 to 4000.00 just the head and your still limited on Z travel, that's almost what a striped 3925 goes for. Maybe another machine would be better suited for horizontal work. I too have a k2 cnc and I love the machine for the way it's designed.

9lrac9

[harryn]

Harryn,
Did your ever get anywhere with the horizontal conversion idea you had? I have a KG3925 and would like to find a way to horizontally mount a router to better do various wood joints.

Hi - I never got a reply that I know of. I don't own a K2 yet, but wanted this general capability. That is one of the reasons I have not purchased anything yet. Budget is the other.

As far as Z axis range, I was not to concerned about that range for the particular project, as it was pretty much a straight drilling application, and I could mount the work to deal with it.

Instead of all that, I am slowly working my way toward a home built, and have a project "log" in the wood working router area. (vertical router project) No real building yet, I am just creating a parts list so far based on the design ideas I have. So far, I keep coming up with more $s to build than I really want to spend, but I guess that is normal.

I would think that it should be feasible to use your 3925 to build up a mount to hold the router horizontally. Once you have the main unit, it seems like it should be possible. Good luck.