wateroftyne Posted May 10, 2008 Share Posted May 10, 2008 (edited) Hi all I have a lovely Boschma 2U rack case. It has fixing holes at the extreme top-and-bottom of each side, and another pair very close together in the middle. Here it is: My current (now old) 2U amp fits in perfectly, screwing into the extreme top-and-bottom holes. You can see where the holes are here: So far, so good... Now, though... I have a new head. It's also 2U - exactly the same height as my old head - but... the holes on the rack ears are much closer together, but nowhere near close enough to line up either set of holes in my rack head. Here's where the holes are: GAH! I thought all this stuff was standardised? Is this a limitation of the rack case? Would an SKB case (for example) have more holes in it and accomodate the new head? I could drill new holes in the case, but I wouldn't be able to fit the cage nuts in (as they fit into a square hole). Is there a way around this? Or... am I buying a new rack case? Ta in advance. Edited May 10, 2008 by wateroftyne Quote Link to comment Share on other sites More sharing options...
warwickhunt Posted May 10, 2008 Share Posted May 10, 2008 Give me a bell MB as I have a rackcase (not a poly one) that 'might' accommodate the amp but it depends on depth! You could also consider trading your 2u for a 3u (not a huge size difference and the amp gets ventilation), someone on here might be up for that. Quote Link to comment Share on other sites More sharing options...
lozbass Posted May 10, 2008 Share Posted May 10, 2008 (edited) Are the holes in the Mesa 1u apart? 'Seems like a strange place to put them unless Mesa expects you to rack with ventilation space. It looks like you're in for a bit of drilling and filing ('should pass an hour though it'd take me a day and I'd still cock it up). I have an SKB (4u) but can't get to it just now - I'll take a look later Edited May 10, 2008 by lozbass Quote Link to comment Share on other sites More sharing options...
Huge Hands Posted May 10, 2008 Share Posted May 10, 2008 As the previous poster said, it looks like it's been made to fit a 1U mount, but then overhang so you are forced to give it top and bottom gaps in a larger rack. From your photo there are no vents on the top casing, which doesn't really appear to back this up. Strange. The side mounts on your case are probably aluminium, so with a good pilot hole you may be able to use decent self tappers? Middle Atlantic (expensive pro install racks) often work on a self tapping theory, so you may be able to get bolts (and possibly even correct thread dies) from them. If you do have to go down that route, PM me and I may be able to have an ask (we deal with their distributor at work). Quote Link to comment Share on other sites More sharing options...
obbm Posted May 10, 2008 Share Posted May 10, 2008 Your rack case and the Warwick are certainly standard. It's the MESA that at first sight appears not to be. What is the distance between hole centres on the MESA? Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 10, 2008 Author Share Posted May 10, 2008 Cheers for all your advice so far! Mr. Hands & Hunt... I may well be in touch. Thanks. The amp doesn't have a vent on the top or bottom, but does on one side. [quote name='obbm' post='195913' date='May 10 2008, 11:48 AM']Your rack case and the Warwick are certainly standard. It's the MESA that at first sight appears not to be. What is the distance between hole centres on the MESA?[/quote] And the answer is... 45mm. Does that shed any light on it? Quote Link to comment Share on other sites More sharing options...
Steve Woodcock Posted May 10, 2008 Share Posted May 10, 2008 (edited) [quote name='wateroftyne' post='195834' date='May 10 2008, 08:40 AM']Would an SKB case (for example) have more holes in it and accomodate the new head?[/quote] SKB and Gator cases do have an extra hole in between the ones on your rack. See here: [url="http://www.pjbproductions.com/SKB-2-space-rack-case.jpg"]2u Rack[/url] Edited May 10, 2008 by Stickman Quote Link to comment Share on other sites More sharing options...
BassBod Posted May 10, 2008 Share Posted May 10, 2008 I've had the same problem with 90's SWR stuff - 2U case but hole spacing requires a 3U space. I'm sure they did this to make sure there was cooling space around the amps (they do get hot, and use aluminium cases to get rid of the heat, as well as noisy fans). SKB have more holes, so you can use them with no problem - but check they haven't changed their designs recently. The new "roto-moulded" stuff also doesn't have the aluminium rack rail that bends when it gets dropped. BB Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 10, 2008 Author Share Posted May 10, 2008 (edited) Thanks again! Huge Hands... are you suggesting that if I got these self-tappers, I wouldn't need a cage nut or anything on the other side? That might be a goer, because a ) I really like my Boschma case and b ) I'm now totally skint... Edited May 10, 2008 by wateroftyne Quote Link to comment Share on other sites More sharing options...
warwickhunt Posted May 10, 2008 Share Posted May 10, 2008 [quote name='wateroftyne' post='196063' date='May 10 2008, 04:35 PM']Thanks again! Huge Hands... are you suggesting that if I got these self-tappers, I wouldn't need a cage nut or anything on the other side? That might be a goer, because a ) I really like my Boschma case and b ) I'm now totally skint...[/quote] Sent you an email wit a poss solution if you are self-tapping Quote Link to comment Share on other sites More sharing options...
Huge Hands Posted May 11, 2008 Share Posted May 11, 2008 [quote name='wateroftyne' post='196063' date='May 10 2008, 04:35 PM']Thanks again! Huge Hands... are you suggesting that if I got these self-tappers, I wouldn't need a cage nut or anything on the other side? That might be a goer, because a ) I really like my Boschma case and b ) I'm now totally skint...[/quote] Yup. Let me check into it at work tomorrow before I make a fool of myself, unless Mr Hunt's solution beats me to it! Quote Link to comment Share on other sites More sharing options...
warwickhunt Posted May 11, 2008 Share Posted May 11, 2008 [quote name='Huge Hands' post='196486' date='May 11 2008, 12:48 PM']Yup. Let me check into it at work tomorrow before I make a fool of myself, unless Mr Hunt's solution beats me to it![/quote] Not trying to steal your thunder HH. I just suggested a local (to WoT and I) retailer that specialise in fixings and fastenings, they do all sorts of self tappers and bolt fastenings so I suggest he try them Quote Link to comment Share on other sites More sharing options...
Huge Hands Posted May 14, 2008 Share Posted May 14, 2008 WoT, I spoke to the guys at work about the Middle Atlantic racks. Apparently their holes are a tapped hole for their own bolts (no cage nuts required). Apparently our guys then often drill and re-tap them to the standard M6 size. They reckon the Mid Atlantic steel is too tough to self tap. They reckon you could probably self tap the aluminium sides on your case, but would always recommend doing it properly by tapping out the hole with a die and then using bolts I don't know if that's of any use whatsoever, and probably too late! Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 14, 2008 Author Share Posted May 14, 2008 It's very useful, Mr. Hands - ta for that. I'll get my Pa on the case ('scuse the pun) 'cos he's good at this stuff and I'm rubbish. Quote Link to comment Share on other sites More sharing options...
DanOwens Posted May 14, 2008 Share Posted May 14, 2008 Sorry I'm late guys but my Warwick Rockbag has an unusual system that would really solve this problem. The nuts for the items are in runners up each end of the case, thereby allowing you to dictate where the screws go. The tension between the nut and runner caused by the tightening of a screw keeps all the gear in place, and allows you to bypass any unusual hole-configurations. Dan Quote Link to comment Share on other sites More sharing options...
Huge Hands Posted May 14, 2008 Share Posted May 14, 2008 Grrr! I used to hate these rack cases, the nut would always slide away up the channel behind the rack ear when tring to fit! Quote Link to comment Share on other sites More sharing options...
DanOwens Posted May 14, 2008 Share Posted May 14, 2008 I got past this by making sure the opening of the case is facing up, and fishing inside with a watchmaker's screwdriver so the nut's aligned. Then the nut won't drop. Dan Quote Link to comment Share on other sites More sharing options...
Mokl Posted May 14, 2008 Share Posted May 14, 2008 Oh, so this is about mounting amps into cases?! When I saw the topic title "Rack sizes and holes", I was expecting something else :blush: Actually, is it just me or is this thread full of double entendres? e.g. [i]The tension between the nut and runner caused by the tightening of a screw keeps all the gear in place, and allows you to bypass any unusual hole-configurations.[/i] I'll get my coat. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 14, 2008 Author Share Posted May 14, 2008 [quote name='Mokl' post='199084' date='May 14 2008, 09:43 PM']I'll get my coat.[/quote] Might I suggest a cold shower instead? Quote Link to comment Share on other sites More sharing options...
stoo Posted May 14, 2008 Share Posted May 14, 2008 (edited) Surely the obvious solution is to drill the rack ears on the amp in the conventional place, so that the holes line up with the mounting holes on the rack? Drilling the rack and using self tappers strikes me as a bit of a bodge solution. There'd be a fair bit of force against the threads on the screws for a rack mounted amp, and so self tappers into a fairly thin sheet of ally or steel just aren't going to have enough meat to dig into to guarantee a solid, lasting, fixing. IMHO, anyway - and I've been bodging things for years. Edited May 14, 2008 by stoo Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 15, 2008 Author Share Posted May 15, 2008 [quote name='stoo' post='199222' date='May 15 2008, 12:53 AM']Surely the obvious solution is to drill the rack ears on the amp in the conventional place, so that the holes line up with the mounting holes on the rack?[/quote] It would be, but then the cage nuts wouldn't fit... Quote Link to comment Share on other sites More sharing options...
Mottlefeeder Posted May 15, 2008 Share Posted May 15, 2008 [quote name='wateroftyne' post='199351' date='May 15 2008, 10:17 AM']It would be, but then the cage nuts wouldn't fit...[/quote] I'm not sure what you read into that post, but to me it means: drill the amp to match where the cage nuts already are. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 15, 2008 Author Share Posted May 15, 2008 [quote name='Mottlefeeder' post='199475' date='May 15 2008, 12:23 PM']I'm not sure what you read into that post, but to me it means: drill the amp to match where the cage nuts already are.[/quote] Oh, right... *slaps forehead* I'd rather buy another case, to be honest..! Quote Link to comment Share on other sites More sharing options...
Jobiebass Posted May 15, 2008 Share Posted May 15, 2008 oops, i came to this post by mistake, thought it was an off topic post about women. Quote Link to comment Share on other sites More sharing options...
wateroftyne Posted May 15, 2008 Author Share Posted May 15, 2008 Sorted! WoT Snr. drilled new holes in the case, and shaped them so the cage nuts fit. I would have done it, but... err... umm.. I was busy doing something really important. Quite smart it looks, too... Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.