Beginning the Thomas Penrose Planing Forms

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Titelines		#41	[url]	[-]
Posts: 1419 05/22/2009 10:37 Admin	Battenkiller wrote: JimmyB11 wrote: After reading all of this and after making 4 sets of forms in a machine shop my advice to anyone thinking about doing this is to a) spend the money on decent forms or b) find a second hand set. It is so much work with no guarantee that the forms will be decent. The whole draw filing thing is scary. Spend your time and effort on a more fruitful rod building adventure. It was seeing three different sets of commercially available forms that made me and a friend decide we could do better ourselves. Lots of little annoyances and a few really bad mistakes in the ones he had before. As I said before, I subcontracted the drilling and tapping. I have completed the scary draw filing thing without a hitch. I have cut the grooves for the roughing form with a 60º thread cutting lathe tool as recommended and it worked great. Now all I have to do is to cut the final two tapers on the finishing form and I've saved myself $900 and I have forms made of 1" square stock that are a full 7' long. What seemed impossible when I first read about it was just a lot of work and some very sore thumbs. The money I saved is more than a bale of cane and all the parts I will need for about a dozen rods, plus a really nice Mitutoyo 2904S dial indicator. I will have enough for a large blowtorch and the parts for a beveler if I ever go that way. Maybe even enough left over for a binder and a rod wrapper. But most of all, it was a really fun project for me that left me with a very satisfying sense of accomplishment. Now, the question is whether or not to go with .005 or .006" spacing between the bars. .006" will give me pretty close to the standard Garrison slope of .001"/inch while going to a .005" spacing will give me a slope about 15% less steep. Is there any advantage to a slower rise (i.e. making the straight sections in the regressive butt tapers of many of the Young designs)? Any disadvantages? Well, the Garrison forms are on 5" centers and have a slope of .001" per inch, so I'm not sure how you got a slope of .006" per every five inches. Most all the tapers available out there today are based on 5" centers of the adjusting bolts. Did you make your forms on 6" adjusting bolt centers? A difference of .001" of slop per 5" could cause some interesting effects over the length of the section. Mark Si vis pacem, para bellum.
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Lewis B		#42	[url]	[-]
Posts: 7 05/27/2009 07:57	things I learned were: dont use hot rolled steel, Its real real hard to file, use cold rolled like the instuction say! Second, If you are like me and own a cheap table top drill press, use 3/4 stock, one inch is even better. The reason is that its hard to drill all the hole dead center. With larger stock your holes can be slightly off center and your file will not hit the bolts when your filing the groove. Looking down the side of my forms you can easily see that my bolt holes are not all on center, whats important is that the holes are straight (at a 90*) and that they are not so far off center that the file will hit the bolts. the last thing to keep in mind; the tip end should be .025 deep . mine ended up at about .031 and it does cause a problemon lighter rods. I built mine for around 70$ . One more thing. When tapping one of my set screw holes I broke the tap off and could not get it out, I moved to the other side of the sholder bolt and drilled a new hole.seems towrk just fine Lewis B
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Battenkiller		#43	[url]	[-]
Posts: 15 05/28/2009 01:35	Titelines wrote: Well, the Garrison forms are on 5" centers and have a slope of .001" per inch, so I'm not sure how you got a slope of .006" per every five inches. Most all the tapers available out there today are based on 5" centers of the adjusting bolts. Did you make your forms on 6" adjusting bolt centers? A difference of .001" of slop per 5" could cause some interesting effects over the length of the section. Mark Didn't mean to be confusing. The Penrose instructions call for the use of a dial caliper to measure the distance between the two bars at 5" intervals. Since this gives you the spacing between the bars rather than the actual depth at that station, you need adjust for this difference. To quote what he has to say about this on his website (the underlining is mine): Since we want the depth of our groove to decrease by .005 inches from one station to the next, the width of the groove will actually end up needing to be greater than .005, and should actually be .00577" (since .005/sin60 = .00577. Another way of looking at it is that the side of an equilateral triangle is approx 15.5% greater than the triangle's height). Hence, if we set the width between the forms so that each station is .00577" more widely spaced than the previous station, the groove we cut would end up being .005" shallower from one station to the next, and this is what is correct. However, using this .00577 measurement poses its own problems, since we are now dealing with ten thousandth of an inch increments, which are not practical for our purposes. Likewise, rounding these numbers off might result in problems keeping the slope of the groove uniform, and uniformity is our main concern here. Whether the slope of the groove falls at .001" per inch or .0015" per inch is not really important, since the adjustability of the bolts at each station of the forms will allow you to set the forms to make virtually any rod taper you want to make. What is important is that this slope is uniform and has no dips or flat spots in it. Consequently, I will suggest that you simply use a .006 increment between stations, or .005, and not worry about using a .00577 width increment. For the sake of these instructions I will simply stick with .005, since it is what I have used in the past. However, a .006 width will actually give results that are closer to the .005 groove depth that is commonly prescribed. So my question is if there is any advantage/disadvantage to a slower rise in the planing form taper. Of course, you still have to set each 5" station to the correct depth for the taper chosen.
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Titelines		#44	[url]	[-]
Posts: 1422 05/28/2009 09:52 Admin	Okay, I understand what you are saying now. I mis-read slope for spacing between the bars. My mistake. If you can get a hold of an inside micrometer similar to this one: inside mic, you can dead-nuts the .00577" spacing of the forms fairly easily, contrary to what is written in the penrose directions. All depends on how anal you want to get... Mark Si vis pacem, para bellum.
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RokSAN	Grinding bell	#45	[url]	[-]
Posts: 4 09/10/2009 03:29	Hello to all! Firs of all forgive me about my English! J Yesterday I try to finish my planning form for making tapers. Before half year I try to make this form with filing but I quote on the half way under 2 days of filing. My hand was exhausted and destructed. So I give up! Until yesterday! I was finally got what I was looking for a half year. The tool which I was looking for was grinding stone like bell or pot for filing steel. In the past I use it a lot for grinding stones, but those one was for stone and not for steel. So I buy this grinding stone and set up on grindery (flex machine). I start to grind the form and on my surprise it goes very good. The only problem was that the grindstone and the form start to overheated. Although I us leather gloves I get burned on my hand! So be careful! But best of all was that I finished just in 1 hour!!!! Can you imagine! Then I was filing with fine file ½ hour that I make fine surface on form. Today is my plane that I make 60° "canal" in both sides on form. I'm thinking that I will make one more form for the first part (first form for making 30° and 60°angle). I try to put some picture on but I can not. Any advice?!?! Grinding machine http://images.google.si/imgres?imgurl=http://www.nakupovanje.net/images/250x/Makita-9557HN-kotna-brusilka--1195584.jpg&imgrefurl=http://www.nakupovanje.net/makita-9557hn-kotna-brusilka--pr-1195584&usg=__uXRpFUc_4AD0p2SS5OLasMesqP0=&h=250&w=250&sz=10&hl=sl&start=24&um=1&tbnid=GXGRq6zyXwV6LM:&tbnh=111&tbnw=111&prev=/images%3Fq%3Dkotna%2Bbrusilka%26ndsp%3D20%26hl%3Dsl%26sa%3DN%26start%3D20%26um%3D1 Grinder http://www.domet-prom.hr/images/program/rezneploce/lonci.jpg Have a nice grinding! SPLETNI MUHAR My flyfishing WEBstore
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RokSAN	Filing 60° canal	#46	[url]	[-]
Posts: 5 09/11/2009 03:03	Yesterday I start with filing 60° canal in still form and must admit frankly that is one big hard work. In only 1h I destroy triangle file. I don't know how you guys make your still form like that. When I was preparing the form and the distends batwing steps on form (every 5'' .005'' withers) I didn't know on which depth must I start to filing. I start from but side with distends .170'' and on the next step .175'' and so one. Is this OK? What kind of file are you using for filing? (Pictures) SPLETNI MUHAR My flyfishing WEBstore
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satbuilder	Look Here	#47	[url]	[-]
Posts: 34 09/21/2009 20:46	In particular, David Bolin's form making tool. http://www.bamboorodmaking.com/html/jigs__tool_building.html
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Beginning the Thomas Penrose Planing Forms

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