Dimpling True Temper OX Platinum
#1
Full Member
Thread Starter
Dimpling True Temper OX Platinum
I have a bike with a little less tire clearance at the chainstays than I'd like. As far as I know, it's made of True Temper OX Platinum - the frame is a 2009 Gary Fisher Presidio. It's identical to the Lemond Poprad when they were built with TT.
Now, I don't actually know for sure if the stays are OX Platinum, or only the main triangle. But if they are, is it a bad idea to attempt to dimple them? Is there a higher chance of causing damage compared to a non-hardened steel, or is it just more difficult?
Any advice is welcomed. I've researched dimpling stays on this forum and elsewhere, but the materials question has me wondering if it's even feasible.
Now, I don't actually know for sure if the stays are OX Platinum, or only the main triangle. But if they are, is it a bad idea to attempt to dimple them? Is there a higher chance of causing damage compared to a non-hardened steel, or is it just more difficult?
Any advice is welcomed. I've researched dimpling stays on this forum and elsewhere, but the materials question has me wondering if it's even feasible.
#2
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,053
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4194 Post(s)
Liked 3,837 Times
in
2,295 Posts
The wonderment as to whether the stays are OX Plat is a valid one. Many frames likely only have two tubes of it, the top and down tubes. All the others often need some forming or machining during the build and that goes easier with more common 4130.
Have you dimpled any stays yet? How many MMs of added clearance, per side, are you seeking? What tool would you use? Andy (who has used a broom handle and a hammer to do this before)
Have you dimpled any stays yet? How many MMs of added clearance, per side, are you seeking? What tool would you use? Andy (who has used a broom handle and a hammer to do this before)
__________________
AndrewRStewart
AndrewRStewart
#3
Randomhead
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 24,385
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 3,686 Times
in
2,509 Posts
if it is oxplat, dimpling it successfully will be difficult. you will probably dent it
#4
Full Member
Thread Starter
If it helps - the chainstays are approximately 31mm x 18mm oval at the bottom bracket, transitioning to 12mm round at the dropout.
#5
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,053
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4194 Post(s)
Liked 3,837 Times
in
2,295 Posts
Being already fairly ovalized I'd be hesitant to further narrow them down too much. 5mm out of 18mm is a lot even before brazing them up. Even if just 4130. I might consider an inside only indent of about 3mm. I would do this with a localized contact form or rounded blade. Not a wood form. But it's your bike and whatever happens is what happens. Andy
__________________
AndrewRStewart
AndrewRStewart
#6
Full Member
Thread Starter
Thanks for the advice. I fully expected to be told it was a bad idea, I think I'll shelve this for now.
#7
Team Beer
Join Date: Apr 2004
Location: Sacramento CA
Posts: 6,339
Bikes: Too Many
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 114 Post(s)
Liked 159 Times
in
104 Posts
How much clearance are you trying to get? I have 40 mm Nanos on 23 mm rims on my OX Plat Poprad. They are snug but work really well.
__________________
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
#8
Banned.
Join Date: Jun 2004
Location: Torrance, CA
Posts: 3,061
Bikes: Homebuilt steel
Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 2193 Post(s)
Liked 425 Times
in
337 Posts
According to info on the Henry James website the tall 30mm chain stays are made from Verus heat treated steel. I've worked with this material before and it's nowhere near as hard as the OXPlatinum alloy. I think you could dimple it 3mm but I agree that localized dimpling would be preferable over flattening the stay over a large area.
Likes For Nessism:
#9
Full Member
Thread Starter
Currently I have 37mm WTB Riddlers mounted on 17mm internal-width rims. They measure 37mm wide at the knobs, and only have around 2mm clearance on either side. Ideally I'd like to be able to fit a 38mm or 40mm tire on a wider rim with a little more clearance than this.
#10
Full Member
Thread Starter
According to info on the Henry James website the tall 30mm chain stays are made from Verus heat treated steel. I've worked with this material before and it's nowhere near as hard as the OXPlatinum alloy. I think you could dimple it 3mm but I agree that localized dimpling would be preferable over flattening the stay over a large area.
When you say localized dimpling, can you provide a picture with an example? I interpret that to mean a dimple that doesn't extend very far along the length stay.
#11
Team Beer
Join Date: Apr 2004
Location: Sacramento CA
Posts: 6,339
Bikes: Too Many
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 114 Post(s)
Liked 159 Times
in
104 Posts
How snug is snug? I'm surprised you are able to make that work.
Currently I have 37mm WTB Riddlers mounted on 17mm internal-width rims. They measure 37mm wide at the knobs, and only have around 2mm clearance on either side. Ideally I'd like to be able to fit a 38mm or 40mm tire on a wider rim with a little more clearance than this.
Currently I have 37mm WTB Riddlers mounted on 17mm internal-width rims. They measure 37mm wide at the knobs, and only have around 2mm clearance on either side. Ideally I'd like to be able to fit a 38mm or 40mm tire on a wider rim with a little more clearance than this.
__________________
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
#12
Senior Member
Join Date: Feb 2012
Location: Rochester, NY
Posts: 18,053
Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Stewart 650B ATB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4194 Post(s)
Liked 3,837 Times
in
2,295 Posts
These two shots show a couple of different tools I've made for crimping. The thick block tool was #1 and for pre brazed stays works really well. The erector set tool fits an already made frame and also works well but with more bits going on takes longer to set up. Note the indenting forms, they are hand cut and filed. I decided that the crimps I will do will tend to be rather localized to clear at a specific point for a specific tire or ring need.
Here's a shot showing both tire and ring crimps as I am setting up a chainstay fit/brazing. This frame is a fixed gear rollers bike and has rather tight clearances overall, note that the stays are not ovalized much to begin with.
I did try to make a crimper out of a large channel lock pliers. I brazed a cupping piece of tubing on one jaw and the form on the other jaw. But for the stay wall thicknesses I played with found that I didn't have enough strength to indent much at all. So onto screw pressured tooling I went. If you were local to me I'd offer to help you out. Andy
__________________
AndrewRStewart
AndrewRStewart
#13
Senior Member
I just made a crimping tool from an old Vise-Grip. Had to crimp in steps so that the tool could be closed, but it did work. The form was the wrong shape so I have to redo it and make it more like the form in the picture above.