Dummy Brake Drum?

[Greg51T&CWagon]

I saw this mentioned in Motors 14th ed manual. A drum made with an open face to adjust the shoes with a feeler gauge. Obviously you'd need to know the difference between your drum and the dummy or keep them turned to the same size. Is it feasible to create a dummy drum by machining a port or ports on the front face? Thinking since i'm converting the front to disk,  I'd only need one for the rear

If this has been discussed before I apologize, I've searched high and low for any mention of this.

Greg

[desoto1939]

Before cutting the drum i would suggest that you take the two old rear drums off the car and then take them to a good brake shop and have them mic the drums to get th exact measurement.  With this information than you might possibly find a good used drum that might have the same or very close measurement. If this can be found then cut the hole inthe spare drum and then you would have a better brake drum relationship to your permanent drums.

 

If the distance is too great then you are close as we say in horseshoes and quates but no real cigar.

 

Rich Hartung

desoto1939@aol.com

[DrDoctor]

Greg51T&CWagon,

   I saw this nifty tool in the accompanying (sorry, but I don’t recall exactly where I saw it), and tho’t it’d make adjusting these Lockheed brakes a snap. When I inquired here about where to find such a contraption, it didn’t go well. I still think it’d be a great item to have, but I seemed to be the only one who tho’t so. Warmest regards . . . .

 

[desoto1939]

42 minutes ago, DrDoctor said:

Greg51T&CWagon,

 

   I saw this nifty tool in the accompanying (sorry, but I don’t recall exactly where I saw it), and tho’t it’d make adjusting these Lockheed brakes a snap. When I inquired here about where to find such a contraption, it didn’t go well. I still think it’d be a great item to have, but I seemed to be the only one who tho’t so. Warmest regards . . . .

 

 

 

 

 

The tool is good for adjusting the brake linings but remember the fact that the tool in the picture is probably set to the eact meaurement of say 10 or 11 or 12 depending on your particular car.  If you drums have been turn or cut as we say then the internal diameter of you original drums will have a larger diameter than you tool. You will be close enought ot get a good setting and then might have to do a minor adjustment with the upper half moon  cam.

 

can be done and I think with good results.

Rich Hartung

[Greg51T&CWagon]

I was thinking I'd get a drum in good condition and take mine with it to be turned and ask the machinist to cut, mill? the ports in the extra one. So they're all the same. That red gage above? could someone print one of those with enough integrity/rigidity to work? but i'd assume cutting an old drum would be much cheaper.

greg

 

[casper50]

I"d say that the red one most likely has a metal inside the plastic coating.

Edited June 22, 2018 by casper50

[jeffsunzeri]

The purpose of such tools is not to set the shoe-drum clearance. The tool is meant to use on non-self centering brakes, where the first adjustment is to make sure the shoes are centered in the drum. There is an eccentric on the non-centering brakes that allows this centering adjustment that is adjusted while this open-drum tool is used.

After centering using the open-drum tool, it is removed and the running drum is replaced and the fine adjusters are used to take up clearance as the drum is rotated to feel and hear the shoes drag.

[DrDoctor]

   Hmmmmm . . . . . Gentlemen, it seems as tho’ the reaction to that red brake gizmo is significantly more positive than the first time I presented. For that, I thank each and every one of you. I looked all over the internet for it, and got bingo results. On the larger photo I have of it, it doesn’t look home-made.  I tho’t, and still do, that using some ¼” strap, and some heavy-walled tubing, one could be fabricated, but getting the concentric tolerance close enough would be the major problem, which is why I’ve not pursued fabricating one. Does anyone know where such a tool could be acquired? Or, do you think one could be constructed that could be maneuvered to be closer than “close enough for gov’t work”? Best regards to all of you . . . .

[Greg51T&CWagon]

Thought I'd post the passages in the Motor Manual that I referred to showing how to use a dummy drum to set the shoe clearances in lieu of a Ammco gage.

greg

 

[DrDoctor]

Greg51T&CWagon,

   That’s GREAT!!!!! Now comes the challenge—where to locate a dummy drum fixture. I think that doing so maybe problematic. So, I’m really warming to your idea of creating a dummy drum fixture by making openings in a brake drum. I’m of the opinion that it’d be less stressful than trying to fabricate one from scratch, or trying to locate one already made. By chance, did your Motor Manual make any mention of where such a dummy drum fixture could be obtained? Again, Thank You for the drawing, and for the idea of modifying a drum.   Warmest regards . . . .

Edited June 23, 2018 by DrDoctor

[Greg51T&CWagon]

Sorry it only says that little bit I copied. I shouldn't think it would be that expensive to convert a drum? just need to start with one identical to the two you have on the car. Or know what the exact difference is. The Dummy would have to be bigger but not smaller obv. 

Greg

[P15-D24]

My .02 worth. With a flangette, bearing and dial indicator you can have a proper adjustment tool for less than $20.00. Plus it will be more accurate.  If you want to go really cheap, skip the dial indicator and just use feeler gauges. 

[Mike36]

These brakes can be accurately adjusted using a cheap dial caliper. Example: if you have a 10 inch drum, the distance from center of axle to contact area of shoe is 5 inches. Since you cannot measure from center of axle, add 1/2 axle diameter to 5 inches, and measure from outer edge of axle to outer edge of shoe. Very simple, very easy, very cheap, and it works good. No expensive tool needed. Subtract desired shoe clearance from 1/2 drum inner diameter, add 1/2 axle diameter. 10 inch drum, with 1 inch axle, and .010 clearance equals 5.490 reading on dial caliper.

[dmartin_egroup]

Hi:

Regarding the tool called a dummy drum, If it could be fabricated with the inside diameter a little less than the desired final size, and IF it replicates the real drum, then a drum turning machine should be able turn/cut the I.D. of the tool to any reasonable size.  Just my humble opinion!

 

Dennis M. in W. Tenn.

[brian b]

I  tried pretty much this same trick, having a shop cut a piece out of an extra drum to use to adjust the shoes.  Didn't work as well as I hoped,   didn't get the improvement in stopping power I wanted.  Later learned of the practice of  honing the shoes to match the drum diameter.  I had no shop able to do this,  and wound up converting to a disc set up.  

   That said,  if you want to be able to use a feeler gauge, consider a hole or two in the backing plate.  This would be easier to do  at home, and you could probably get a rubber plug to go in the hole created.   Placed in the right spot, you could see the shoe/ drum contact, and get a feeler gauge in to set the adjustment.

 

                                                                                                                                                                                brian b

[desoto1939]

1 hour ago, brian b said:

I  tried pretty much this same trick, having a shop cut a piece out of an extra drum to use to adjust the shoes.  Didn't work as well as I hoped,   didn't get the improvement in stopping power I wanted.  Later learned of the practice of  honing the shoes to match the drum diameter.  I had no shop able to do this,  and wound up converting to a disc set up.  

   That said,  if you want to be able to use a feeler gauge, consider a hole or two in the backing plate.  This would be easier to do  at home, and you could probably get a rubber plug to go in the hole created.   Placed in the right spot, you could see the shoe/ drum contact, and get a feeler gauge in to set the adjustment.

 

                                                                                                                                                                                brian b

I think that trying to cut two holes for a total of four into the very outer edge of the backing plate is going to be very hard to do becasue the  holes have to be so far out so that you are almost on the entire outer edge of the backing plate to get the  feeler gage into the slots and then you would have to have the car up on a lift to beable to set the shoes.  The dummy drum was used by alot of old time mechanic and should get you very close to a good brake,  After doing a brake ajustment with the ammco brake gage 1750 which I have several of them and also the factory Miller MT19 tool you still need to perform a minor adjust by using the upper half moon adjuster not the eccentric adjuster to get the final setting of the shoes.  Also remember that you need to depress the brake pedal after setting each indidual wheel this feels with getting the shoes set properly for each wheel.  This is how I was taught to do this by an old time mechanic.

 

Rich Hartung

desoto1939@aol.com