I need a manual for a Delta TP300 Planer

Go to http://servicenet.dewalt.com, put your model number in the search box and you'll be able to view/download the parts breakdown and owner's manual.

It is involved so I recommend going to "dewaltservicenet.com" and under manuals on the left hand side type in your model number and it will redirect you to a page so that you can download the owners manual, it is 17 pages long and the area you need is around pages 10-11 which deals with blade changing. REMEMBER to unplug the tool before starting this. Let me know if you need more assistance

make sure the blades are seated and locked down correctly

You can get the manual on the link below.

http://dl.owneriq.net/d/d56363f4-6fd3-34b4-edad-2156452f698c.pdf

Try tu make a jumper at the switch, if it start change the on/off switch.

http://powertool.manualsonline.com/manuals/mfg/delta/tp300.html

when standing at the back of the planer you should be able to see the beveled edge, the flat side of the blade should be facing the front of the planer.

I replaced blades on my planer and now the wood is getting chatter on it, why?

Heres your Manual:

http://powertool.manualsonline.com/manuals/mfg/delta/tp300.html

you will need the directions from the owners manual , do not guess at this it can be a hazard if not done properly i have manual and will try to look it up and figure how to get the info to you