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Is it possible to run any miter gears up close to 30k rpm? This would be driven by a porter cable router, so around 2hp.
Any advice is welcome, I would hate to spend a bunch of time just to have gears detonate on me. I am not finding much info in this area!
Could plastic gears handle the hp?
If no gear could stand up to it, do you have any other suggestions for transmitting power at 90degrees?
Joe
There are air tools with right angle heads - they spin pretty fast. As does an angle grinder. But those might not have the power capacity. If a right angle drill could handle those speeds (might need to change grease to some other lube method) it should be fine for the power.
Sounds like a tough problem. Your best answers will be from the gear companies -- Boston Gear, Martin, Berg, SDP-SI, etc.
I agree keeping lube on the gears will be an issue, and also heat buildup and noise. Plastic would probably melt, although would be quiet until then. One thing in your favor is that Power = Torque * RPM; so the more RPM, the less torque, and the smaller the gears and teeth can be.
Martin http://www.martinsprocket.com/docs/d....pdf?sfvrsn=12
says their straight miter gears are good for a pitch line velocity of 1100 FPM. The formula is FPM = 0.262 * PD * RPM, so at 30,000 RPM the max PD would be 0.14" -- tiny and hard to imagine 2 HP through that. Martin's smallest gear (M2424) has a PD of 1.0". Berg and SDP specialize more in the small pitch gears -- I'd ask them about your app.
Angle grinders use spiral bevels, probably to reduce noise and diameter for a given torque capacity. But they have big reductions, so a 30k rpm output would need a super fast input. Even good angle grinder gears tend to self-destruct under heavy use -- they may have pushed the pitch velocity, anticipating the tools don't usually see long use.
Is there a good way to make your part without a right angle head?
Even these very expensive aggregate heads for larger routers only have a max spindle rpm of 10,000. I don't think you'll get anything to last at 30k.
Techniks Function Line Mono Agggregate Head For CNC Routers
I guess I could put a variable speed on the router, and limit it to 10 or 15 thousand. Or I could do a 2:1 reduction, but wouldn't it still be a problem that the input was at 30k? I really don't need the horsepower for my application. I need to produce a part in one setup in a relatively high production manner. I planned to build a head similar to what Gerry posted, but with a second tool out the opposite side. The whole head has to rotate 180 degrees. I could mount a router horizontally, but two routers horizontal that have to rotate start to take up a lot of room.
If 1/3 HP is enough, how about 2 of these: Ingersoll Rand 302A Heavy Duty 1/4-Inch Angle Die Grinder - Amazon.com
If 1/4 HP is enough, HF has a $15 version.
If not and if two routers would fit horizontally (even taking up a lot of room), that seems far easier than designing and making a right angle head.
Ok, I think I decided to mount two opposing routers horizontally with 180 degree indexing. I am going to jack the whole gantry up to help with the clearance. Saves a lot of potential for failure.
Thanks!
Joe
Here is the final solution, ready to start building. The indexing is pneumatically driven, locking at 0, 90 and 180.Attachment 213576