Otto Posted May 28, 2012 Share Posted May 28, 2012 I picked up a bunch of AM B-25 kits for next to nothing. I know the cowlings are useless on this kit. I also know there are replacement aftermarket cowls available. The question is, which are correct. Some people say that the cowls should be round by the firewall and some say they are oval. Both the AM and Monogram and Revell kits are oval. will the new cowls Fix this? If so than how since the nacelles are still oval in the front? Any thoughts? Quote Link to post Share on other sites
DonSS3 Posted May 28, 2012 Share Posted May 28, 2012 I wouldn't say that they're useless. My understanding is that the major issue with them is that the cowl openings are slightly two small. A few minutes with a "tube" of sandaper should take care of that. Just MHO, of course… Quote Link to post Share on other sites
Otto Posted May 28, 2012 Author Share Posted May 28, 2012 (edited) I wouldn't say that they're useless. My understanding is that the major issue with them is that the cowl openings are slightly two small. A few minutes with a "tube" of sandaper should take care of that. Just MHO, of course… I took the advantage of this wonderful holiday and did some research. I found out three things about the cowls. The first thing is that you are correct that enlarging the hole to 36" scale .75" ours is the first step. That makes a big difference. The wonderful tool for that is a step drill. i bought mine at Harbor Freight Tools and use it for 75% of my drilling duties. I used it to mount my roof rack rails on my Jeep Unlimited Sahara Safari yesterday and used it to enlarge the openings today on the B-25 cowls. Two weeks ago I used it to cut the hole on my Skyraider cowling. Amazing tool. http://www.harborfre...ills-96275.html http://www.harborfre...ills-91616.html The second of the three things I found out, is that the upper ogive curve is wrong. So first I enlarged the hole with the step drill which took about a minute or less, and than I examined the upper shape from the profile. It is quite square at the top and has a pronounced drop off at the front. Looking at pictures that is quite wrong and quite noticeable. OK if I'm going to replace them anyway, why not try to reshape them before I do so. I pulled out some 320 wet dry paper and started sanding in a circular motion around the upper half of the front speedring in about a 45* angle to the opening. I concentrated on the area in front of the panel line detail. I figured that I can slightly intrude over the panel line to continue the smooth shape but I did not want to loose the panel line or the Zeus fastener heads. I slightly deepened the panel line and made sure that i did not sand more than 50% the depth of the fasteners. The third thing I found out is that replacement cowlings cost money. More money than I want to put in a project hat is not at the top of my list and as i just found for myself can be fixed quite easily just by using my modeling skills and about 20 minutes of time per cowl. Thanks Don, for saving me some money which can be used elsewhere more efficiently and productively. Here is the kit part stock and re-shaped one next to it. It may not be perfect but is 100% better than the stock part, 100% cheaper than an aftermarket part and more than close enough to look good on the kit. Edited May 28, 2012 by Otto Quote Link to post Share on other sites
100th BG Posted May 28, 2012 Share Posted May 28, 2012 I purchased a set of the Quickboost 1/48th B-25 cowls and found them to be way too small. They will not fit the AM or Monogram kits. Don't know if I just got a bad set or if it is a common problem. Their 1/72nd B-25 cowls are a perfect fit though. Like the previous posters have said, just open up the front and you will improve the looks considerably. Quote Link to post Share on other sites
Otto Posted May 28, 2012 Author Share Posted May 28, 2012 I purchased a set of the Quickboost 1/48th B-25 cowls and found them to be way too small. They will not fit the AM or Monogram kits. Don't know if I just got a bad set or if it is a common problem. Their 1/72nd B-25 cowls are a perfect fit though. Like the previous posters have said, just open up the front and you will improve the looks considerably. I have noticed that everything I have purchased from Quick Boost was WAY too small. Thanks for letting us know, that was going to be my #1 choice if my endeavor failed. I have had bad luck with Quick Boost. They may not take into account the shrinkage of the resin they use. As I mentioned and you can see from the pictures, I am EXTREMELY happy with my reshaped kit cowls. I bought 4 extra sets for $2.50 each on eBay so I have plenty to play with. I have already toasted one set for a different experiment but still have plenty left. Quote Link to post Share on other sites
metroman Posted May 28, 2012 Share Posted May 28, 2012 B-25B kit with too small openings was later fixed with the C/D version - according to Cybermodeler and MM sites. Quote Link to post Share on other sites
Robertson Posted May 28, 2012 Share Posted May 28, 2012 (edited) B-25B kit with too small openings was later fixed with the C/D version - according to Cybermodeler and MM sites. Not true for a 2006 limited edition C/D AM kit I have (so 6+ years after it came out): This problem was, as far as I know, never fixed in any AM or even Italeri issue, and what Otto succeeded in doing with the cowlings is quite hard to do concentrically with just sandpaper... I can also confirm the Quickboost cowls are too small, and certainly won't cover the oval firewall shape of either B-25 kits, and may even be too small just in diameter. Robertson Edited May 28, 2012 by Robertson Quote Link to post Share on other sites
Otto Posted May 28, 2012 Author Share Posted May 28, 2012 (edited) The step drill sets are one of the best tools I have ever bought. If you need to open a hole in anything that is 3/16" deep or less there is no better tool. The one I used for this project is the one on the right on the 3/4 step. The 7/8 I used for the Skyraider cowls I made in the Monogram Skyraider Thread. http://s362974870.onlinehome.us/forums/air/index.php?showtopic=246859 Edited May 28, 2012 by Otto Quote Link to post Share on other sites
DonSS3 Posted May 29, 2012 Share Posted May 29, 2012 Glad I could inspire you, Otto, and save you money to boot! Cheers Quote Link to post Share on other sites
Otto Posted May 29, 2012 Author Share Posted May 29, 2012 Glad I could inspire you, Otto, and save you money to boot! Cheers I would much rather model than spend the money for something some other dufis muddled. Quote Link to post Share on other sites
dnl42 Posted May 30, 2012 Share Posted May 30, 2012 Don't quite grok the description of the 2nd mod, after enlarging the opening. Can you provide a sketch? Quote Link to post Share on other sites
Otto Posted May 30, 2012 Author Share Posted May 30, 2012 (edited) The curvature drop at the top is too sharp and too far forward on the kit cowlings. The radius should be greater and start quite a bit farther back. It should be more "sweeping" threw the upper cowling than dropping off at the front like it do. The sand paper did a nice job with out taking off all the detail. Edited May 30, 2012 by Otto Quote Link to post Share on other sites
Otto Posted June 1, 2012 Author Share Posted June 1, 2012 Don't quite grok the description of the 2nd mod, after enlarging the opening. Can you provide a sketch? OK I hope you can see the shape differences between the tops of the two cowlings. The openings are both enlarged to the right size and than I rolled up a piece of paper and let it unroll between them to hold them perfectly aligned. Ironically the darkest picture shows the difference the best. The kit part is on the left and the modified part is on the right. I am providing the same picture in three different illumination intensities. Hopefully the difference is visible on the curvature of the top front of the cowlings. It is much more apparent to the naked eye than it is in the photo. Quote Link to post Share on other sites
Otto Posted June 3, 2012 Author Share Posted June 3, 2012 Has anyone ever figured out why AM put those stupid cut-outs at the top of the cowls below the scoops?? Quote Link to post Share on other sites
Prop Duster Posted June 5, 2012 Share Posted June 5, 2012 Has anyone ever figured out why AM put those stupid cut-outs at the top of the cowls below the scoops?? 'Cause they would look stupid anywhere else??......Never Mind Seriously your drilling and sanding has got'er done. Good work, may not satisfy some, but for my money a real cool solution, that I'll use on my B-25. Quote Link to post Share on other sites
Otto Posted June 5, 2012 Author Share Posted June 5, 2012 (edited) 'Cause they would look stupid anywhere else??......Never Mind Seriously your drilling and sanding has got'er done. Good work, may not satisfy some, but for my money a real cool solution, that I'll use on my B-25. Since the Cutting Edge ones are no longer available there are no others. I am not even sure that anyone ever did a set for the early version and the ones from the Czech Republic (I forgot their name at the moment) are greatly undersize.I started filling in those cut outs on mine and it is working out nicely.Quick Boost !!! thats it! By the way, the Cutting edge ones had a big problem also, they made the cowling round like it should be but left a big step in the transition to the nacell at the bottom.Those also had to compensate for the scoop at the top with a small releaf but it was not a cutout like the stock ones. The more I look at mine the more I like them. Edited June 5, 2012 by Otto Quote Link to post Share on other sites
KSL Posted June 5, 2012 Share Posted June 5, 2012 Since the Cutting Edge ones are no longer available there are no others. DMold makes them as well: http://dmold-modelworks.com/contents/en-us/d2_01.html Sergey. Quote Link to post Share on other sites
Otto Posted June 5, 2012 Author Share Posted June 5, 2012 DMold makes them as well: http://dmold-modelwo...n-us/d2_01.html Sergey. Thanks for the notification Sergey. I saw those some time ago. Unfortunately, every time I have looked at them, they are not available. They are out of production. Quote Link to post Share on other sites
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