zoltan Posted December 29, 2011 Report Share Posted December 29, 2011 Last season I bought Head boots and modified them to use the BTS, and used it successfully all last season. However, when drilling the boot for the BTS pins, I think I may have used a slightly too large bit. The pins are still snug in the holes, but I don't need a hammer to push them out - I can do it by hand (with some effort). So, I'm worried if the pins aren't tight enough the holes in the shell might deform or get bigger, which might lead to damaging the shell or losing the pin, neither of which would be good. So, is this something I even need to worry about? If it is, I was thinking of maybe using a spring pin to make sure it's really snug. With the pins I've found, I'd only lose 15% sheer strength going to a spring pin. Alternately, considering I just picked up a new mini lathe, I could make pins which are slightly larger than the stock ones. Quote Link to comment Share on other sites More sharing options...
jp1 Posted December 29, 2011 Report Share Posted December 29, 2011 zoltan, If you have a caliper or a micrometer, measure the OD of your pins. I don't remember (without looking back thru the threads what they 'should' be, but pretty sure they were metric) I may have some material around that I could cut to length and send to you ? Quote Link to comment Share on other sites More sharing options...
zoltan Posted December 29, 2011 Author Report Share Posted December 29, 2011 The pins are 4.95mm diameter. If I turned some new pins myself, I'd probably go 5.1mm (and make the BTS holes slightly larger). The spring pins I'm considering are these: Quote Link to comment Share on other sites More sharing options...
piusthedrcarve Posted December 29, 2011 Report Share Posted December 29, 2011 ......I was thinking of maybe using a spring pin to make sure it's really snug. With the pins I've found, I'd only lose 15% sheer strength going to a spring pin. Alternately, considering I just picked up a new mini lathe, I could make pins which are slightly larger than the stock ones. Those pins are what I used for upper pins. I used HSP stock one for lower pins. When I first put them in, I hammered in. Now, I can use my hands to put them in (of course, with some effort). Since the HSP's upper parts are not rigid plastic (more like rubberish one), I think the tightness will not be matter as much as rigid plastic like deeluxe/raichle. Quote Link to comment Share on other sites More sharing options...
jp1 Posted December 29, 2011 Report Share Posted December 29, 2011 zoltan, personally (JMO) I would not use a Roll Pin (Spring Pin) as their static tolerances are not precise. I've never seen a Roll Pin that was round / concentric, because they are desinged to compress when installed in a hole of a specific diameter. Remember the Top Mount of the BTS has to pivot on this pin. An 'oval' shaped pin would be asking for accelerated wear. Sorry, I couldn't find any left over shafting. I did look in McMaster Carr Catalog (#112, older so prices are probably not current) and there are a few choices that would work better than Roll Pins (IMO). Stainless Steel (18-8) Metric Dowel Pins would be my first choice if they are long enough (45mm long) # 91585A138, pkg. of 10 = $7.41. Miniture Precision Stainless Steel (316) Shafting (metric) 5mm X 200mm # 1265K44 $ 10.49. Tool Steel (page 3460) .201" diameter. Drill Rod (page 3451) Tight Tolerance Rods, .201" dia # 88645K36 = $ 2.89. Metric Shafting (page 988) 5mm X 200mm #6112K37 = $ 6.37 Hope this helps ...... Quote Link to comment Share on other sites More sharing options...
zoltan Posted January 1, 2012 Author Report Share Posted January 1, 2012 Good point. I was looking at McMaster myself (it might be my favorite site) and was thinking of either just getting a 5mm dowel, a plug gauge (available in 0.005" increments), or just buying some stock and turning the pins myself. The BTS' pivot hole is 5.1mm diameter, and I'd rather not drill it larger unless absolutely necessary, so that limits me. Do you think 316 stainless would be strong enough, or should I stick with carbon steel? zoltan, personally (JMO) I would not use a Roll Pin (Spring Pin) as their static tolerances are not precise. I've never seen a Roll Pin that was round / concentric, because they are desinged to compress when installed in a hole of a specific diameter. Remember the Top Mount of the BTS has to pivot on this pin. An 'oval' shaped pin would be asking for accelerated wear. Sorry, I couldn't find any left over shafting. I did look in McMaster Carr Catalog (#112, older so prices are probably not current) and there are a few choices that would work better than Roll Pins (IMO). Stainless Steel (18-8) Metric Dowel Pins would be my first choice if they are long enough (45mm long) # 91585A138, pkg. of 10 = $7.41. Miniture Precision Stainless Steel (316) Shafting (metric) 5mm X 200mm # 1265K44 $ 10.49. Tool Steel (page 3460) .201" diameter. Drill Rod (page 3451) Tight Tolerance Rods, .201" dia # 88645K36 = $ 2.89. Metric Shafting (page 988) 5mm X 200mm #6112K37 = $ 6.37 Hope this helps ...... Quote Link to comment Share on other sites More sharing options...
John E Posted January 2, 2012 Report Share Posted January 2, 2012 I think the intended fit is to have the press fit of the pin into the plastic of the boot and a slip fit into the aluminum upper BTS "head". If you use a roll pin, it will likely reverse this fit. If you get a press fit into the aluminum, I think you'll be OK. The pin will then rotate in the plastic. This may not be ideal but should work OK at least for a while. I wouldn't worry about the strength of a roll pin (versus a dowel). I think if there is a failure, it will likely be the plastic of the boot cuff. McMaster-Carr is possibly my favorite site as well. So easy to find exactly what you want. I think you'll be OK. Let us know how it works. Quote Link to comment Share on other sites More sharing options...
SEJ Posted January 2, 2012 Report Share Posted January 2, 2012 I assume you're doing this at room temp. The colder it gets the more the plastic will shrink in relation to the metal. Typically, plastics have a MUCH higher coefficient of thermal expansion compared to metals. Quote Link to comment Share on other sites More sharing options...
zoltan Posted January 2, 2012 Author Report Share Posted January 2, 2012 That's a really good point I never even considered. Gracias. Quote Link to comment Share on other sites More sharing options...
michael.a Posted January 3, 2012 Report Share Posted January 3, 2012 I used some threaded bolts, I think 5mm, then cut off the heads and hammered everything em in. However, after a few years, the bolts slowly push themselves out about 5mm, so every 2-3 days of riding I got to hammer them back in. But if you can push them out/in by hand, then they are too loose IMO. Quote Link to comment Share on other sites More sharing options...
lafcadio Posted January 3, 2012 Report Share Posted January 3, 2012 Maybe I missed it in an earlier post, but can't the pins for the Raichle/Deeluxe boots be used? Bomber stocks these and the BTS is made to fit them. http://www.bomberonline.com/store/boots/parts_pins.cfm Quote Link to comment Share on other sites More sharing options...
piusthedrcarve Posted January 3, 2012 Report Share Posted January 3, 2012 Maybe I missed it in an earlier post, but can't the pins for the Raichle/Deeluxe boots be used? Bomber stocks these and the BTS is made to fit them. http://www.bomberonline.com/store/boots/parts_pins.cfm Deeluxe's long pin is about 1.5". Mod. on HSP needs about 2" Quote Link to comment Share on other sites More sharing options...
bumpyride Posted January 3, 2012 Report Share Posted January 3, 2012 How about a stainless bolt and lock nut smaller in diameter to keep the pin from backing out? Quote Link to comment Share on other sites More sharing options...
Gossamer Posted January 4, 2012 Report Share Posted January 4, 2012 I've been riding like this for 3 years and it's never come loose, find the right size bolt to thread into plastic, put a drop on it before installing and Dremel to length. Quote Link to comment Share on other sites More sharing options...
jp1 Posted January 4, 2012 Report Share Posted January 4, 2012 I hope you guys that are using Stainless Steel bolts are using long bolts that are not threaded all the way and the 'shoulder' (non threaded area) is the bearing surface in the BTS and the bolt then cut to length. Otherwise I wouldn't want to see what the inside bore of the Aluminum BTS looks like from the Stainless Steel threads (just saying). Quote Link to comment Share on other sites More sharing options...
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