DeWalt DWS780 put on new blade and when I manually rotate blade I hear/feel grinding. Is brake doing its thing or some other new problem if I plug in and start up. Thanks

Have it trepaired under warranty.
https://servicenet.dewalt.com/documents/English/Instruction%20Manual/N466020,DWS780.pdf

Most Dewalt manuals are available here: https://servicenet.dewalt.com/Home . There are 40 Dewalt power tools with 321 in the model number. Several are jigsaws. There are two types for the DW321 (TO3PAK-2LE JIG SAW) jigsaw. Please look at the label on the jigsaw to ensure that you get the correct model and type. The direct link to the manual for the DW321 Type 1 is currently https://servicenet.dewalt.com/Products/GetDocument?docName=402086-01,DW321.pdf&productId=2841&productType=3001&documentId=24909&translatedFileName=http://documents.dewalt.com/documents/English/Instruction%20Manual/402086-01,DW321.pdf .

To change the regular blade on the DW321 type 1, unplug the power tool. To remove the blade, pull the knob on the top of the jigsaw up about 1/4". Rotate the knob counterclockwise until the clamp opens. Do not force the knob after it stops. Insert the blade making sure that the back edge of the blade fits into the support roller. Rotate the knob clockwise until it clicks and then push it down.

I hope this helps.

Cindy Wells

Hit in the rear axle may have damaged bearings or brake parts. Jack up the side you hear noise from, put on stand, then have helper rotate wheel while you look underneath and listen to see where noise is coming from. Use length of old fuel or heater hose, one end in ear, to locate exactly where noise comes from.

Have you checked the manual. My Dewalt Dws780 was not turning on, then I checked the manual and able to start it. There was some sort of plug issue with my saw but thankfully it sorted out quickly. I got this saw from this video recommendation.

You can get the manual on the link below. Look to the rigt of the picture to get the manual.

http://servicenet.dewalt.com/Products/Detail/DW735

Point tool away from body.

2. Rotate blade clamp collar (the knurled diamond pattern knob just at the back of where the blade goes) to release position.

3. Insert blade shank from the front.
4. Rotate blade clamp collar to lock blade into position.

Make sure this unit is NOT plugged in. The blade needs to be in a lock position to loosen the blade nut. Most units have a safety pin that engages into the revolving portion. Once you locate this pin, press it in then SLOWLY rotate the blade by hand until you feel it engage. At this point the blade will no longer rotate. Keeping the blade locked, use your wrench and place it around the center nut and turn CLOCKWISE. The thread is left handed, so when startup the unit, the blade nut continuously tightens up.

remove the blade guard, should be a big nut holding on blade remove that nut install new blade, make sure the rotation arrow on your new blade is going same direction as old blade reinstall the big nut and washer , put guard back on you should be set! good luck

I guess that you are releasing the handle for the tilt? When released does it feel like it did? Does the carriage move any? What I would do is unplug the saw and put it on a workbench or floor and carefully tilt the saw on its back edge, holding the guard to keep if from falling quickly. Look under the saw for a bent rail and if not try to push the saw tilt by hand pushing on the bottom guard. You might have to lubricate the slide underneath or loosen up the locking mechanism. If you need a copy of the owners manual I would go to Dewaltservicenet.com and typing in your model number to download it. I really don't think it is anything major. Let me know