Trying To go FASTER!!!

[daniel]

Hey Guys, I have a possible job that doesn't leave a lot of room for profit
So I'm using it as an oppurtunity to figure out how to cut faster, therefore increasing my profit.(As long as edge quality doesn't decrease)

I have a standard PRT 48 with a Makita Router,
and a vacuum table running on one Fein.

Here is what I'm currently cutting:

3/4" Birch Plywood

I'm using a 1/4" downspiral bit (Bosch)
I am running it 1.7 inch/min at .25 inch depth per pass.
I run the router between 15,000 and 18,000

How can I cut faster? Does increasing to a 1/2" bit help? I think I could make deeper passes with the 1/2" bit, but I don't know how it would effect the feed speed?

I also see alot of 1/2" and 1/4" speacialty bits from onsrud ( Chipbreakers, finishers, O flutes)
Anyone using any of those with good results?

Any info is great!
Thanks!

[richards]

The small cutter (1/4) has less load on the router motor, when compared to 3/8" and 1/2".

Before I changed to a spindle, my favorite cutter for cutting plywood was a 3/8", 1-flute, down-spiral cutter.

In your case, you might try running a 1-flute 1/4" cutter at 3/8" depth per pass. That would cut 1/3rd off the machining time. Then, you might try setting your feed speed a little higher. (Go as fast as you can until you start to loose steps, and then back off a little.)

Also, run the router as slow as possible, even with a 1/4" cutter - if your feed speed maxes out at 1.7 - 2.0 IPS. You want a chip size 0.010" to 0.15" to keep from burning up cutters. Most routers loose power as you turn the speed down, so you might have to keep the speed up to make the cut. A little testing in some scrap will help you find the best compromise.

[seana]

Daniel,
I cut alot of plywood with an older prt.
I had a pc router and changed to Milwaukee, i realize i cut a lot more aggressive then most but it might work for you.
Fist cut 1.9ips, 13,000rpm depth of .6 with an .04 offset
Second cut 1.9ips, 13000rpm depth of .75 on profile.
For both cuts i use a 2 flute .25 compression. I used to use a single flute but found that the cost for the 2 flute was half the cost so i swithced to them and still get 16-20 sheet out of a cutter. Most of what i'm cutting is bamboo plywood and it is full of silica so it eats the cutters.
very little to no sanding of edges.
I use two riged vacs for hold down and tabs on the smaller parts.

Give it a try, on a sheet of scrap and see how it does for you.

Sean

[tree]

Well a good thing to keep in mind when tring to bump up speeds and feeds in the method in which you are holding you parts. I have a PRS 60"x96" with 6 zones and I stay around 3.00 - 3.80 IPS @ 13000 RPMs with a 2 flute downspiral .250 bit in .750 baltic birch with an average cut depth of .250. I know I could prob get alittle more, but I only need to work so fast. Also keep in mind that it might be more effective to cut aggressively eventhough your bit may ware faster. Just look at the cost of the bit in return to the profits of the production gained by faster machining.

[daniel]

Thanks for the input guys. I will heed these suggestions next time I cut. As for this time, After a good nights sleep, I think I'm going to turn the job down after all. Just not enough profit to be made

Thanks again!