Share Your Secrets and Shop Tricks!

Thought a thread of tricks would be nice.....

Here is one of my favorites I use it weekly....

Need a good finish for a clearance hole, but don't have a reamer or want to take the time to set up a boring head?

offset an endmill with shimstock or piece of paper in the collet of your mill.....enlarges the radius size by about 80% of thickness of shim....if your paper is .0035....hole usually enlarges by about .0055 diameter.....

worth taking a test cut the first few times if tolerances is tight, but for clearance holes, I just should in a piece or two and go for it....works perfect

works well with powerfeed or just feed by hand

here are a pic




Enjoy!

Care to share any of yours?

xdmp22 said:

enlarges the radius size by about 80% of thickness of shim....if your paper is .0035....hole usually enlarges by about .0055 diameter.....

Click to expand...

Good tip. I'll steal it if you don't mind. Thank you.

Here's a few more:

http://www.practicalmachinist.com/vb/general-archive/tricks-trade-96842/

Steve

One I have used in cases where I needed some clearance- the best example is drilling screw clearance holes on location in the mill, and then coming back and using an endmill as a counterbore. Of course, the drill has been a clearance drill, say 17/32" for a 1/2" screw.

In the same example, the screw head will be 3/4", requiring a 25/32" diameter. I will use a 3/4" endmill and plunge cut my counterbore depth. Then I will come back +/- .015" at each axis and plunge the same depth. This will normally be enough for clearance, but to finesse it a bit, I will move at 45 degrees in each direction by multiplying .015" x .7(sine/cosine of 45 degrees). Most of the time this is just a head calculation; 70% of .010" is .007, plus half again is .0105.

So this movement is x =+.0105, y =.0105, work it all four directions and make a plunge cut each time. The result rarely looks "scalloped," it's clearance anyway, and usually can have the job done (unless I have a lot of holes to do) in a shorter time than it takes to find a proper counterbore (if I even have one).

^^^^^^^

That works, I have been known to use my the shim trick for counterbores with endmills too.....end mills do work good for counter bores...




Thanks for the link...my search foo must have been broken.....

Brazing :

In case you are not exactly shure, add more flux, you can never have too much of it. (Unless you are doing volume production and care about those 5 cents)

Brazing wire with seperate flux generally flows better than flux covered or cored rod without additional flux. In really difficult cases where the flux might try to escape you can use both at the same time, flux and flux covered wire.

Be shure to get even heat distribution, especially silver solder is extremely sensitive to heat distribution. If you braze a cap on something, dont place the cap on your firebrick, it may look like it insulates the cap from heat loss, but in reality it insulates it from the flame.

If parts are a rather loose fit , hit the mating surfaces with a centerpunch, if you do it right it will create a uniform gap for the braze to fill and it will give you a fake interference fit so the initial bubbling from the flux cant move your parts.

If that doesnt work, use a brazing spider. Its a wire tripod with a weight on top. Place one leg on the part that might try to swim on the flux and move.

A good brazed joint is hardly visible !


(Yeah , i do a lot of silver brazing and soldering because it is the perfect method for a lot of problems, i once broke a bolt on the Colchester, oddball OEM part with a BSW thread we dont have tooling for, silver brazed it back together, the layman wouldnt see the joint. typical example)

Zonko said:

If that doesnt work, use a brazing spider. Its a wire tripod with a weight on top. Place one leg on the part that might try to swim on the flux and move.

Click to expand...

A.k.a. "welder's finger".

Brazing and Aluminum Tips

When brazing, make sure your parts are vertical if possible, 30-40 degrees, Total vertical is best, NOT FLAT, that way the bronze will only flow when the part is tinned correctly, then the bronze shelf can be made and layered upon each other. No joint strength with out proper tinning, I also use 3 types of flux if parts will not tin correctly, a little dip in each can and you can be sure the tinning will take effect.. if brazing is done correctly, the joint will be stronger than the part itself..

I have brazed many Euclid Truck transfer cases, (when i was much younger) these bare transfer cases weigh about 3-4000 lbs. 7ft high and 5-6ft wide, I would build a wall with fire brick and (back then) cover every thing with asbestos sheets,,, then have 4 or 5 propane torches going for 3-4 hours, until the case was glowing red and the crack has closed, (the crack was sometimes 5-6ft long)

Then reach in as far as the heat would let me and start tinning and brazing, maybe 2-4" at a time,, then cool off awhile, then back to brazing, got to be a long day.. from start to finish, could be a very hot 12-14 hr day, profit was great, new cases were in the thousands of dollars... THE GOOD OLD DAYS...

Also, when gas welding aluminum, or pot metal, about 4-6 degrees before the part sags, you will see very small beads of moisture form, Time to get the heat of or apply filler rod.

If you ever need to weld a carburetor, melt down an old one, pour it onto a 3/4" of angle iron, now you have your filler rod, and of the same similar material... use the same process as with aluminum.

Tim

Very good tips Zonko,

Hear hear, now thats some experience there, intresting, very.

You said bronze, i suppose bronze as in spelter , high temperature braze ?

Because this "keep it vertical thing" i have never seen, read or used in connection with silver solder.
Work i do is usually less than one kilogram, so while i have brazed a bit with other stuff like silphos bronze , i usually use the finest grade of silver solder which is really expensive but gives the superb results because it flows as thin as acetone does when you drip it on something.
No need for "tinning either" , just distribute the heat evenly, hit and go watch as the solder penetrates 1" of joint or more just by capilliary action.
Its quite pretty.....

Zonko, You are correct,

Filler metal is also called brazing rod, spelter, or brazing alloy. ... As the name implies, brazing is usually done with a filler made of some form of brass or bronze, (GOOGLE)

I have only used silver solder for bandsaw blades, This is how I do It...

1) Create a 1/4 - 3/8" scarf joint
2) Clean with a touch of acetone
3) Apply flux to scarfed surfaces
4) Securely mount to blade welding fixture
5) Cut a piece of Silver Solder the width of blade
6) Lay Silver Solder at joint were they meet
7) Slowly heat joint with a neutral flame opposite the Solder
8) Be Patient, when Solder flows by capillary action, remove heat immediately
9) Let cool, cleanup joint of flux and use small file if needed

If done correctly, blade will wear out before joint failure.

NOTE: Use compatible flux and silver solder, or else you will have problems

ZONKO: Any Sugestions ????

Thats by the book ehh, couldn't add a thing. Alas, we dont have a bandsaw.


But you made a good point : If you have difficult joints you can just put a piece of solder on the joint and heat it up. You will usually be a able to make due with a little less heat, and you shure as hell wont cause misalignment to parts with a careless twitch of the solder wire.

But keep the wire on the table, in case you can see a defect in the joint, thats the Moment you should fix it.

I learned this timesaver tip on one of these forums. If you have something in your hand and your'e not going to use it, put it away where it belongs. Won't take you half an hour to find it next time you need it. Peter

HELP!! I need to know a good way to cut 85/8"hole in SS piping

We need to find a cleaner way to cut large holes in 12 inch & large stainless steel 304 sch 5 & 10 piping with the holes needed 8 & 5/8". We use a plasma cutter now but the holes are too jagged and the pipe gets smoked up with slag in the pipe. We need to know what others would do to make the holes cleaner and faster in the pipe. Any ideas would be helpful.

SS Pipe

Sidecar, so the plasma wont work, are you using a template of some sort to cut the hole? I know they can be smokey and dirty but you should get a good cut if you have plasma setting correct. Just cut some today at my shop and barely any cleanup.

Many years ago I did use a 10" diamond hole saw to cut transition holes in 16" SS, sch 10, took about 10 min a hole, and used soluble oil for lubricant and cooling. Don't know cost of hole saw. Anything with diamond impregnation is not cheap.

Have used a 1/8" carbide bit in a router on aluminum with a template and worked great, but SS is not Aluminum

Good Luck
Tim

Agreed, use a template or jig for the plasma....it will smoke and a little slag, but won't be jagged like freehand cutting......

Also, the hole to be cut is within arms reach of the end, get some pam or other cooking sprey and spray the backside of the hole and the enitire OD where the slag will hit....slag will just rub/scrape off with a welding glove or light putty knife...if you use the stuff with butter in it, it will smell like breakfast too

Cutting SS with Plaz

I haven't used the plaz to cut much stainless, but make sure you have a high enough setting. When I have had trouble in the past with slag, I have just turned up my air pressure some more. Also try using an inert gas. I know your gas supplier will be able to help with the gas selection. The gas should cut your slag down.

Josh

add to the bandsaw blade silver solder. I use a propane torch and only heat on the bottom of the joint till the silver flows. Its easy to get too much heat with a oxy-act. Another thing I do is hammer the joint on a flat surface after it has cooled completely to flatten out the blade.
Regards
Greg Hornbostel

I could tell you some of my secrets from my government days... but then I'd be thrown jail for violating state secrets, but heres a handy hint for all you working in the nuclear industry

When machining plutonium, make sure the pile of chips in the bottom of the lathe does'nt get beyond 9.8kg in weight, otherwise it all goes very hot and runny and you die several minutes later...

Boris

More handy tips tommorrow

Not to be a critical (m)ass Boris but it's past tomorrow*.
*counter to Annies philosophy.

Inquiring minds (and subversives) want to know...more.

Like: is it necessary to squeeze the chips or does fluffy become runny @ 9.8Kg too?

Funny how mixing elements of fusion and fission, like throwing deuterium, well, it's deutrons, at U238....

....never mind, I don't want to be on the exclusive list you are on....can discussing anything (or everything) in the public domain...does MI6 chat with CIA...are they related through their mutual middle initial......is Intelligence otherwise banned...is Iran intelligent...is this like using the four letter word "bomb" on a commercial flight...?

Back into my midsummer night's dream....

Puck..er.. Bob

Does anyone know a trick for keeping flux and silver solder out of regions of the workpiece ( e.g. threads, gearteeth) where you do not want it to go?