Cylinder honing

[Jeff02]

Anyone ever used a Brake Cylinder Hone on a .750 Steam Engine cylinder?
Or do you have a better way?

http://www.mytoolstore.com/kd/kdbrak08.html

http://www.toolsource.com/brake-cylinder-flexhone-grit-p-98075.html

Thanks,
Jeff

 

[erik58]

A fixed adjustable hone would be better. you can make adjustment if the cylinder is tapered or out of round. a automotive machine shop could do it for you. the hones are pricey. good luck Erik ;D

 

[Bogstandard]

Jeff,

I have one of those hone sets.
You have to be careful about the size you select, as they come in a range of sizes.

I only ever used it on the last ic engine I made. A 1" bore cast iron liner, and it worked a treat.

The bore distorted slightly as the liner was pressed into the ali block.
I did purchase some very fine stones to use in it though, and plenty of oil while in use. Only took about 5 minutes to straighten everything out.

John

 

[jpaul]

Jeff,
For a piston and cylinder you want a cylinder that is truly round and without a taper. The finger stones you reference will not assure this result unless your cylinder is round, non tapered and smooth to begin with. These finger stones are fine for polishing or cross hatching the surface, removing very little material (.0005" or less) . For anything more, like removing tool marks, scoring, and pits and for truing an out of round cylinder, you need a different tool.

Examples of calender laps have been featured on this site. Hopefully someone can direct you to previous post. Meanwhile I will photograph several laps I have made and post my pictures tomorrow.

 

[carbide_burner]

I found an excellent e-book (pdf) on stirling engines on the net. Unfortunately I don't know the name of the book, as it has no cover page... I will attach a page of how to make a wooden lap. Enlarge it about double size to get the text clear enough to read. I used this technique with great success. One important note: This is by no means (as any other honing operation) a fix for taper or oval bores. Machine it right, then hone it, then admire your work ;D

 

[jpaul]

Three cylinder laps. From left to right.

A 1 inch plastic union (pipe) between Two 1" pipe nipples. When fitted the plastic pipe was turned to size.

The middle lap is brass cylinder with a 2MT2 bore. It is drawn over a 2MT arbor that has a sheet metal key to mate a slit in the brass lap.

The Third lap is a 3/4" commercially made product. It uses a tapered draw screw to expand the lap cylinder.

 

[Florian]

And this is how i do it:

I apply polishing compound and lots of oil to hone the cylinder. This works really good. For expanding the slotted mandrel, I grinded a flat cone on the screw. (Is it the way to express this?)The threads in the mandrel are shorter than the screw but the center hole is deep enough to allow the screw expanding the single "jaws"
I used 1000 u/min for honig with this 8mm tool. Oh, by the way, it was a brass cylinder i honed.

Florian

 

[Willy]

Hi Guys

Has anyone made a Lap that can be used in a blind cylinder. (The cylinder and head are as one) Most Laps I have seen have a short stub on them that prevents it from lapping right out to the end of the Lap.

Willy

 

[Florian]

Hi Willy

You just need to redesign my kint of lapping mandrel and it will work. The chamfer on the front of the tool ist just for better entering the hole. But you can also make a chamfer on the part to hone, so this isnt any problem. If you want, you can also make the center hole through the mandrel and cut the threads from behind.
If you don't get it, I'll make a sketch for you.

Florian

 

[Jeff02]

Thanks for ALL the great Ideas and Help!

The cylinder in question is a STUART V10 it was bored and not drilled so it should be in the round and not tapered, I Hope!

Thanks again for you Help!

 

[Paula]

Hi Jeff,

I have also used the commercially made expanding laps -- with very good results. Though there are numerous sources, I got mine from Travers Tool:

There is also a version for blind hole lapping:

Paula

 

[raym 11]

Paula;

I have a set of the barrel laps to 1". Do you know of a source for larger ones 1 1/8" or 1 1/4"?

Ray M

 

[Paula]

Hi Ray,

Yes, Travers has these same laps in 1-1/8 "and 1-1/4" sizes. They also have a 1-1/2" size, but not in the blind-hole style.

Travers Catalog page 940

Paula

Addendum: I have successfully lapped larger size bores by just using an accurately-turned steel rod, a few thousandths under the bore size. This is the method that Phil Duclos describes for lapping his "Odds'n Ends" engine.

 

[raym 11]

Thank you Paula.

I just ordered some stuff from Travers and I didn't know about that. They didn't charge me postage so I'll order the lap.

Raym

 

[Jeff02]

Paula, Thanks Again for the tip.

I will be ordering one of these, looks like it will do the job just fine.

 

[Tin Falcon]

Here is another option for smoothing out cylinders
http://www.mytoolstore.com/kd/kdbrak08.html
K & D tools makes hones for rebouilding brake cylinders available at your local auto parts store and of course e-bay.
Tin