| Author |
Message |
Brent
Samba Member
Joined: April 28, 2010
Posts: 1614
Location: San Tan Valley, AZ
|
 Posted: Sun Jul 28, 2013 12:55 am Post subject: Re: frozen |
 |
|
| daneibling wrote: |
Figured Id let you all know whats working,....or NOT as the case may be.
Ive used most a can of the hig end wd-40 for loosening bolts,...forgot what its called. as well as a good portion of a can of Liquid Wrench
Ive also used a cold chisel and knocked out a notch into the head of the bolt and used the largest flat head at Lowes I could find to try to get it to back out
I even tried cold chiseling around the edges, figured it might loosen it up, worst case figured Id break off the head of bolt and have to drill her out
Dry ice is easier to come by for me than a torch,....so tried dry icing the bolt to get it to shrink even a smidge,..just enough to loosen something
Also have gotten REALLY good grip with a vice grip and tapping wrench with a hammer to loosing things up. Considering that the head of the bolt is rounded, I can get a few good taps in before the wrench slips off
I've also tried filing down a side of the bolt head to allow better grip with the wrench.
None of this has worked that bolt hasn't so much as budged.
At this point, I figure I'm just going to have to get some drill bits and drill her out,....the bolt is toast anyways,...and I just want to get this job done. I have yet to take of the other wheel,...so who knows,...I might have two more frozen bolts to deal with after this one. |
You can get a butane or MAP torch from Home Depot for about $10-$15. Heat will make a huge difference in getting a stuck bolt loose. Just heat the drum around the bolt.
_________________
69 Fastback Build
Berg5 Build |
|
| Back to top |
|
 |
Yabbadubbadoo
Samba Member
Joined: May 21, 2012
Posts: 914
|
| Posted: Fri Sep 25, 2020 3:46 pm Post subject: Re: Rear Drums? |
|
|
Might as well revive an old thread. I searched for rear drum brake fitments issues and come up with sporadic evidence that Brazillian repops are machined out-of-round and off centre bolt holes etc. etc.
Anyhow recently I bought 4 stud (Brasil) rear two piece drums without the center hub flange as I already had what appeared to be good vw ones.
Upon fitting the units on fully rebuilt internals with new parts I found a degree of scrub on half the rotation indicating some sort of run-out issue.
Thinking perhaps my centers were out of whack I purchased a set locally as they weren't too expensive, yes Brasilian not genuine but exactly the same issue appears. Approximately 0.40mm of run-out.
Tried different stub axles - same issue.
I tested run-out by inverting the drums so the inside was facing outside and I set up a dial indicator.
I took drums to a brake specialist and he and I deduced that the drums were machined round but the centre of that circle was near impossible to locate because the centre hole of the drum.portion is a bit too large therefore it does not locate well on the hub centric locating lip of the centre hub flange.
From what I can gather Vw designed it such that the lip on the center part locates the outside drum portion. If it's a very loose fit how can you centre the drum on the hub when you tighten the lug bolts?. The bolt holes have a degree of clearance built in so it should work even if the bolt holes are slightly out of centre however there is absolutely no way the system can cope with the drum centre hole being too large for the locating lip.
I'm thinking perhaps I should have bought the same brand centre hub but I thought it was designed in two pieces so you didn't have to buy the hub flange and remove the axle nut every time you need to change the drums.
Looking to try and come up with a work-around to centre the drum on the hub better so I can get them machined as a complete assembly.
_________________
Sydney, Australia.
66 Type 3 Fastback |
|
| Back to top |
|
|
Bobnotch
Samba Member
Joined: July 06, 2003
Posts: 22425
Location: Kimball, Mi
|
| Posted: Fri Sep 25, 2020 8:43 pm Post subject: Re: Rear Drums? |
|
|
The best work around is to find some good used German drums. The ultimate best would be a set of NOS drums. 
_________________
Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
| Tram wrote: |
| "Friends are God's way of apologizing for relatives." |
| Tram wrote: |
| People keep confusing "restored" and "restroyed". |
|
|
| Back to top |
|
|
Yabbadubbadoo
Samba Member
Joined: May 21, 2012
Posts: 914
|
| Posted: Sat Sep 26, 2020 12:20 am Post subject: Re: Rear Drums? |
|
|
| Bobnotch wrote: |
| The best work around is to find some good used German drums. The ultimate best would be a set of NOS drums. |
The brake machinist said its very common on two peice drums to require machining before installing new drums. On trucks its normal to machine new drums. Am I missing something?. Did people just fit them and drive off back in the sixties and seventies or did they give them a lick on the brake lathe first?
Slim pickings on this side of the pond for Nos parts.. I think i can work it out though. I have a spare stub axle which I cut the cv flange off so I have a spindle for the lathe to hold the hub and drum.
I'm thinking of drilling two new m8 locating bolts through the whole assembly but I'll use shoulder bolts on the drum so that its a more accurate fit. I'll punch some reference marks so it goes on the same spot if I pull it apart.
Ill tighten up the lug bolts, drill and tap the locating pins (shoulder bolts) then machine the brake surface once its all solid.
_________________
Sydney, Australia.
66 Type 3 Fastback |
|
| Back to top |
|
|
gt1953
Samba Member
Joined: May 08, 2002
Posts: 13848
Location: White Mountains Arizona
|
| Posted: Sat Sep 26, 2020 8:08 am Post subject: Re: Rear Drums? |
|
|
When I changed out my rear drums for new one from Rock Auto, they were out of round. Had them turned, they are still within specs luckily.
Still watching for some better ones.
_________________
Volkswagen: We tune what we drive.
Numbers Matching VW's are getting harder to find. Source out the most Stock vehicle and keep that way. You will be glad you did.
72 type 1
72 Squareback
({59 Euro bug, 62, 63, 67, 68, 69, 73 type ones 68 & 69 type two, 68 Ghia all sold}) |
|
| Back to top |
|
|
Bobnotch
Samba Member
Joined: July 06, 2003
Posts: 22425
Location: Kimball, Mi
|
| Posted: Sat Sep 26, 2020 8:11 am Post subject: Re: Rear Drums? |
|
|
Well, VW didn't want you to "cut" the drum at all IF possible. And if you had to cut the drum, only take the minimum amount needed for clean up. As they really didn't say it out loud, the drums were pretty thin (like the front rotors). New rotors were only 3mm thicker than the wear limit. I'd have to check a Bentley manual, but I think drums were less than that.
A big part of the problem with the Brazilian drums, is their construction, as they are cast in 1 piece. If you look at a German drum, you'll see that the braking surface is a cast part, that's fused to a "sheet tin" part. The casting is thick where it should be thin. Just something to keep in mind.
_________________
Bob 65 Notch S with Sunroof
71 Notch ...aka Krunchy; build pics here;
http://www.thesamba.com/vw/forum/viewtopic.php?t=249390 -been busy working
64 T-34 Ghia...aka Wolfie, under construction... http://www.thesamba.com/vw/forum/viewtopic.php?t=412120
| Tram wrote: |
| "Friends are God's way of apologizing for relatives." |
| Tram wrote: |
| People keep confusing "restored" and "restroyed". |
|
|
| Back to top |
|
|
raygreenwood
Samba Member
Joined: November 24, 2008
Posts: 21519
Location: Oklahoma City
|
| Posted: Sat Sep 26, 2020 11:06 am Post subject: Re: Rear Drums? |
|
|
| Yabbadubbadoo wrote: |
| Bobnotch wrote: |
| The best work around is to find some good used German drums. The ultimate best would be a set of NOS drums. |
The brake machinist said its very common on two peice drums to require machining before installing new drums. On trucks its normal to machine new drums. Am I missing something?. Did people just fit them and drive off back in the sixties and seventies or did they give them a lick on the brake lathe first?
Slim pickings on this side of the pond for Nos parts.. I think i can work it out though. I have a spare stub axle which I cut the cv flange off so I have a spindle for the lathe to hold the hub and drum.
I'm thinking of drilling two new m8 locating bolts through the whole assembly but I'll use shoulder bolts on the drum so that its a more accurate fit. I'll punch some reference marks so it goes on the same spot if I pull it apart.
Ill tighten up the lug bolts, drill and tap the locating pins (shoulder bolts) then machine the brake surface once its all solid.
|
Two piece drums commonly needing machining?....not really. Maybe on truck drums....maybe on other cars.....but the type 3 and 4 rear two piece drums from the factory were SURPRISINGLY concentric.
The problem has been....and its been since the 90's with "0" improvement.....the Brazilian drums are machined out of round. How much out of round?...all over the place. The last set I bought many years ago...I found a shop that was nice enough to do the footwork because I was a good customer. I bought a pair. Had to return them both. Easily 0.060". Got two more. One was decent at about .010-.015" out of round....the other had to go back. Had to order two more to find one that was "round enough".
On the stock VW drums....the center plate is STEEL....with a nice accurate fit on the flange and with nice accurate M-8 holes. They are done this way...because ....both the outer drum and center locating plate is placed on a precision jig for machine welding.
So yes...back in the 60's and 70's .....you just pulled the drum out of the box and slapped it on and it was within spec.
The only issues were very slight warp areas where the welds were....that causes a high spot. That just creates a short break in period where the edge of the shoe needs to wear to make clearance. But....the original drums were pretty damn concentric.
The reason why other two piece drums might COMMONLY need to be put n the lathe...is because they did no work to get them centered. They just slapped them together.
They ...and even VW's drums....are assembled two piece because they need to have a very flat thin mounting plate. That works far better in steel sheet than it does in thick cast steel or cast iron. And....the center plate is not prone to cracking, the whole assembly is lighter and is also less prone to warpage. Ray |
|
| Back to top |
|
|
Yabbadubbadoo
Samba Member
Joined: May 21, 2012
Posts: 914
|
| Posted: Sat Sep 26, 2020 1:47 pm Post subject: Re: Rear Drums? |
|
|
Thanks guys for the information. Excellent depth of knowledge on this forum. Im still a bit stuck though. Dont have many options at present except to work with Brasilian drums and then keep an eye out for some better oem ones if they appear.
_________________
Sydney, Australia.
66 Type 3 Fastback |
|
| Back to top |
|
|
Qldelsie
Samba Member
Joined: September 22, 2019
Posts: 518
Location: Queensland Australia
|
| Posted: Sat Sep 26, 2020 4:24 pm Post subject: Re: Rear Drums? |
|
|
| Yabbadubbadoo wrote: |
| Thanks guys for the information. Excellent depth of knowledge on this forum. Im still a bit stuck though. Dont have many options at present except to work with Brasilian drums and then keep an eye out for some better oem ones if they appear. |
I feel for you, Yabbadubbadoo - It must be really frustrating, more so because it probably wasn't a problem you ever thought you would have !
I never even thought about the issue - I guess mine are all original so don't have that problem.I just had them refurbished and re-shoed and put them back together, although my brake man is very "old-skool" and always makes sure the new shoes are matched to the drums. He refuses to put new pads on shoes unless he has the drums as well.
I will make sure I brake less often so they wear out more slowly !!
G |
|
| Back to top |
|
|
Yabbadubbadoo
Samba Member
Joined: May 21, 2012
Posts: 914
|
| Posted: Sun Sep 27, 2020 4:35 am Post subject: Re: Rear Drums? |
|
|
| Qldelsie wrote: |
| Yabbadubbadoo wrote: |
| Thanks guys for the information. Excellent depth of knowledge on this forum. Im still a bit stuck though. Dont have many options at present except to work with Brasilian drums and then keep an eye out for some better oem ones if they appear. |
I feel for you, Yabbadubbadoo - It must be really frustrating, more so because it probably wasn't a problem you ever thought you would have !
I never even thought about the issue - I guess mine are all original so don't have that problem.I just had them refurbished and re-shoed and put them back together, although my brake man is very "old-skool" and always makes sure the new shoes are matched to the drums. He refuses to put new pads on shoes unless he has the drums as well.
I will make sure I brake less often so they wear out more slowly !!
G |
Sooner or later you'll hear those words, "they're too far gone mate".
I have an old set, there's not much life in them but going to swing past the brake place and get a professional opinion. I dont have calipers that large but steel ruler puts it very close to the wear limit of 249.5 actually looks more like 250mm
Today a friend came past who just bought type 3 drums from a different aftermarket manufacturer but they were no better on the centre bore displaying a similar degree of loose fit on the hub centre. Also 0.6mm of brake surface run-out on one drum and 0.25 on the other. Even my worn to hell vw drums were only 0.1mm and 0.15mm out. Hes taking them back asap and going to stick with wide five.
I also sent an online query to the supplier of my drums about the issue but haven't got a response yet.
_________________
Sydney, Australia.
66 Type 3 Fastback |
|
| Back to top |
|
|
Cptn. Calzone
Samba Member
Joined: June 27, 2007
Posts: 1855
Location: S>E>Alabama
|
| Posted: Tue Sep 29, 2020 1:30 am Post subject: Re: Rear Drums? |
|
|
Try Autohauz in Az they have good drums from time to time
_________________
71 westfalia
67 912 Porsche Quintilla
67 Single Cab aka my work horse |
|
| Back to top |
|
|
Kepler
Samba Member
Joined: September 27, 2020
Posts: 13
Location: Newburyport, MA
|
| Posted: Sun Nov 21, 2021 4:44 pm Post subject: Re: Rear Drums? |
|
|
| I am trying to figure out if I need to replace the rear drums on my 1970 Type 3. They are original, but I am wondering if they are too worn and should be replaced. There is a bit of a "lip" around the edge so it is clear that they have a bit of wear. Does anyone know the minimum thickness for drums? Any other other recommendations on how to determine if they can be turned vs need to be replaced would be greatly appreciated? |
|
| Back to top |
|
|
gt1953
Samba Member
Joined: May 08, 2002
Posts: 13848
Location: White Mountains Arizona
|
| Posted: Sun Nov 21, 2021 6:05 pm Post subject: Re: Rear Drums? |
|
|
According to the VW Without Guesswork book/manual Maximun wear limit is 249.5mm or 9.823 inches that is the inside diameter. I had the auto part store that turns drums measuer them while I watched. I have no what to measure them.
_________________
Volkswagen: We tune what we drive.
Numbers Matching VW's are getting harder to find. Source out the most Stock vehicle and keep that way. You will be glad you did.
72 type 1
72 Squareback
({59 Euro bug, 62, 63, 67, 68, 69, 73 type ones 68 & 69 type two, 68 Ghia all sold}) |
|
| Back to top |
|
|
|
