Order of Operations

[chucketn]

I'm making an ER32 collet chuck for my 7x lathe. I have 2 pieces of stock. One is 1/2" steel from a scrap plate from a fixture or machine I got from a friend, the other is a piece of 2" steel barstock , also from a friend.I have cut out a circle from the plate with the bandsaw and mounted it on a 1/2" x 13 arbor and cleaned up bothe faces and the circumfrence. Same with the bar. I intend to bore the flat plate to fit the round, MIG weld them together, and turn and bore the chuck on the lathe.
My question is, should I set up the plate on the RT and drill and tap the attaching holes and turn the spindle registry before welding the two together?
I also plan to chamfer the flange plate on both sided of the hole to allow me to get a good weld.
Am I working in the right direction? Any suggestions?
Is welding better than sliver soldering/brazing?

Chuck

Edit: I'm following plans from http://mikesworkshop.weebly.com/er32-collet-chuck.html

 

[purpleknif]

I just bought one on flea bay for around $35. Just sayin'.

 

[chucketn]

Where's the fun in that? If I had more money than I needed, I would probably buy it also. I ran out after buying the collets, that I saved up for...

Chuck

 

[Swifty]

In answer to your original question regarding method of manufacturing, I would machine the hole and rough out the location step in the plate and machine the register on the front piece, then weld them together. If you have some method of heating the welded assembly up to stress relieve the part, it would be great. By heating up and cooling as slow as possible, it will relieve any stresses caused by welding and hopefully stopping future movement. A dull red heat would be ideal, but failing that I would use the kitchen oven on its highest setting, let it stay there for a while, then turn it off and leave it in there until cool. Final machining can then be done.

It would be a shame to put a lot of work into machining the part and then have the runout alter on a hot day. Maybe I'm being over cautious, but it's not a lot more work to stress relieve.

Paul.

 

[bazmak]

Just made the same collet from solid see my thread
I usually fabricate for similar items.I usually bore and face plt
Turn spigot and chamfer round stock and fully electric weld
Front or back but no need for both.Grip in 3 jaw face/recess to fit spindle
Drill and tap 3 no M6 and fit grub screws as studs.Fit to lathe and finish turn everything bore,taper for collet and screw thread.Its easy. No need for stress relieving. Ambient temperature will not have any significant effect.And everything should be within half thou

 

[Brian Rupnow]

Chucketn--as a rule of thumb, all welding should be completed before any machining is done. Metal will move an astounding amount when it is welded.---Brian

 

[bazmak]

Thats correct Brian,but machining for assembly has to be done first
After welding the 50dia stock can be held in the 3 jaw to fully machine for
spindle.When bolted to lathe all finish maching can be done.I skimmed the OD and the 50dia true and then clocked I demounted and remounted 3 posns
to check for concentricity/repeatabiliy.If Ok then rough turn and bore
Finish machining should then be completed in light cuts.
As a footnote an experienced fabricator can judge how much and what direction
distortion will take place.As a general rule i tack weld each end to form a pivot point then stitchwelding alternately each side will pull and hold square.I have just made a large angle plate with gusset plate.The actual distortion was kept to a minimum using this method keeping machining to a minimum