cutting sonotube caps (1 Viewer)

Hey everyone,

I've been lurking on this forum for some time now, but I've reached somewhat of a problem. I've purchased my MDF, drivers, and sonotube, but for the life of me I can't cut my end caps. I attempted using a Craftsman router with a Bosch bit. The problem is I got about 1/4 of the way around my 20" diameter cap and the bit was dull and would no longer cut. I know the answer is probably simple, but I must be missing it and only have a limited time to complete this before going back to college. How did you guys cut your caps? Thanks.

Oldham Viper 1/4", solid carbide, spiral cut, up-twist bits.

$17 or so at evil orange

Yep, make sure you are using carbide and take it slow; you should probably do about 2-3 passes in order to cut through the 3/4" MDF. If you try to cut all at once it puts too much stress on the bit and router causing premature failure.

i prefer Whiteside bits, haven't had a problem with the 5 or so that i own.

I use a Whiteside sprial upcut bit I got from www.woodcraft.com. Also make sure to obey Kyle's suggestion of taking a few for going through the MDF, I usually take 3 passes.

Cut around using a jigsaw first, leaving about 5mm (1/4") for the router to take off. Makes things MUCH easier for the router.

I'm happy with Whiteside as well. There are a lot of good router bits out there but Whiteside has given me the best bang for my buck. They are not the cheapest but are usually the cheapest of the high quality bits. Woodcraft has them but they charge too much for them. I get them from www.routerbits.com.

If you do go with whiteside, the spiral bit you need to order is: RU2100. At routerbits.com it is $14.60. Woodcrafts part number is: 03K33 for the same bit, and they want $21.99 for it.

Another good one is CMT. I like CMT better than Whiteside but they are usually out of my price range on most of their bits. The CMT 1/4" spiral bit is not that bad of price. The CMT bit you would need is model: 191.008.11 and you can get it from sommerfeld tools: http://www.sommerfeldtools.com/products.asp?id=78 for $16.90


Ronnie

Alright I think I got this down. I have a bandsaw at my disposal that I'll use for the outside cut... Thanks all for the help... If anyone else has anymore pointers keep them coming.

Eric,

Getting the bulk of the MDF cut away using a jigsaw (like RodN said) is an excellent suggestion. I didn't have a router, so I made just about all of my cuts using a jigsaw and then finished off the endcaps/plugs with a RotoZip spiral saw. Worked fine for me.

JKS

Try to use router bits with a 1/2" shaft. Much less vibration. The skinny shafts don't hold up nearly as well.

I would use a 1/2" shaft if I could but the collet on my router is only a 1/4". One bit if properly used should get the job done though, correct?

The Oldham Viper bits at Home Depot have a lifetime warranty, so if it dulls on you, return it for a new one.

I made several speakers before my 1/4" shaft bit broke. Like others have said, take your time.

I use a single Oldham bit to built 4 tube subs. That included cutting 1.5" thick bottom plates, in addition to the endcaps