T-Molding Slot Cutting Techniques (What did I do wrong?) ** Noob Question **

[JohnEDollar]

Hi Gang.

I been reading the forums for a while now, trying to "pick up" some good pointers, and techniques, on cutting a t-molding slot in 3/4" MDF.

I've purchased a slot cutter bit and arbor assembly, from http://www.groovygamegear.com.

Following the advise posted in this forum, I've made several "practice cuts" on scrap material, to ensure I had the proper settings on my router. (Test Cut)

When I made the cut on what will be my control panel front, I got the results shown below.  (Pass One) It's as if the router is boring downward in the material.

I'm using a plunge router, with a 1/4" shaft.  I've held the router at the same "angle", and used the same speed and direction, when making my cuts on the "control panel", as I did on the "scrap material".  (Control Panel and Scrap Material are from the same sheet of 4'x8' 3/4" MDF.)

Any ideals of what I may be doing wrong?

(Control Panel slot is bondo-ed and sanded...  ready for attempt number 2!)

Any advice is greatly appreciated.  Thanks.

- John

[Nacimroc]

Is the handle that holds your plunge depth in place becoming loose ? Once the plunge debth is set you should not be able to change it with force. So when you are cutting maybe you are putting pressure on it downwards and its not tight enough to hold it in place?

[JohnEDollar]

Nacimroc:

Thanks for the info.  I'm pretty sure I had all settings securely tight, before making the cuts. 

I'll double-check, and make some more practice cuts.

Would cutting the t-molding slots be easier using a router table?

Thanks again.

- John

[Nacimroc]

As I've never used a router table I couldn't say, but I would assume it would be easier with a hand held router. It is also possible that the bit isn't securely fastened into the collate properly and the shaft is coming out of the router as you move along ?

[JohnEDollar]

Nacimroc:

Thanks again for the tip.  I'll check the collet again, and report my status.

(I won't be able to make any practice cuts/attempts until this weekend.  I'll report my results then.)

Thanks again! 

- John

[Vulgar Soul]

As already said, check the security of your routers locking mechanisms, the collet, and the router bit. All should be tight and secure to keep it in place. Kind of scary actually knowing a 3-wing blade spinning at 3,000 rpm is coming out of place during operation. That should be a cause for alarm to stop and check that all security on the router is in place.

[gryhnd]

As already said, check the security of your routers locking mechanisms, the collet, and the router bit. All should be tight and secure to keep it in place. Kind of scary actually knowing a 3-wing blade spinning at 3,000 30,000 rpm is coming out of place during operation. That should be a cause for alarm to stop and check that all security on the router is in place.

FTFY

(although usually 24,000 is about where they top out)

[spoot]

I had some blade "drift" when I was going to fast....but not the "drift" you got going on there.  Definately check the plunge lock and collet.

[Nacimroc]

And for anyone who think mozii is exagerating, the pic below was taken recently when the hand tightener on the cheap crap router I was using decided to come loose.  The bit went flying across the room and lodged into a piece of MDF.  So be very careful. It would have taken a nice chunk out of my leg if it flew the other way.

[eds1275]

Double check you have the blade facing the correct direction! If your plunge depth is not the culprit, this is a telltale sign of you cutting the wrong way and the blade being pulled from the router by catching on the material.

[Vulgar Soul]

Double check you have the blade facing the correct direction! If your plunge depth is not the culprit, this is a telltale sign of you cutting the wrong way and the blade being pulled from the router by catching on the material.

This to! blade should be spinning clockwise. Turning in the same direction you would tighten a soda cap.

[Nacimroc]

There would probably be burn makes if he had the blade was backwards though ??

[JohnEDollar]

Double check you have the blade facing the correct direction! If your plunge depth is not the culprit, this is a telltale sign of you cutting the wrong way and the blade being pulled from the router by catching on the material.

This to! blade should be spinning clockwise. Turning in the same direction you would tighten a soda cap.

Mozii and eds1275:  Double checked to ensure the slot cutter bit is installed correctly:
(Not my pic, found it on another post on the site. "Flat edge" of router bit strikes the MDF first.)



(Note to RandyT:  An "arbor and slot cutter bit assembly diagram" included with the packaging, or on your website, would be an extremely helpful document for us "noobs" ordering T-molding slot cutters from you!)

I had some blade "drift" when I was going to fast....but not the "drift" you got going on there.  Definately check the plunge lock and collet.

spoot:  I'll check the plunge lock, and collet again.  Thanks.

There would probably be burn makes if he had the blade was backwards though ??

Nacimroc:  I checked the slot cutter bit. No burn marks.

Will have updates over the weekend.  Thanks everyone for all the suggestions and pointers! 

- John

[Vulgar Soul]

(Note to RandyT:  An "arbor and slot cutter bit assembly diagram" included with the packaging, or on your website, would be an extremely helpful document for us "noobs" ordering T-molding slot cutters from you!)

I believe traditionally it goes like this, from top to bottom:

Bearing
Blade
Washer(s)
Nut

Make sure the nut is fastened tight! If that blade slips off, you will be waking up in the hospital lol.

[mgb]

I have an older router that slip down a bit if you press too hard. Maybe thats happening here??
On my bit, the bearing is below the blade and then the nut. so the bearing rolls on the surface below the cut.

[JohnEDollar]

Success!!!!

Double-checked all my settings, and made sure everything was tightened properly. 

Made a few "test cuts" again, and PRESTO!!!  Perfect t-moulding slot!

I guess my plunge depth adjustment wasn't as tight/secure as it could have been previously, and the adjustment changed when making my cuts.  Also, I think I may have "pivoted" the angle of the router on the material, causing the cutter to "dig" into the MDF, as shown in (Pass One).

Thanks, gang, for all your help, and suggestions on this issue.  (I love this forum!)

(Sorry, no pics - camera got stolen.)

- John