The 'Pocket Rocket 2000' is the complete five-minute line boring tool specially designed to bore VW cases for installation of oversize bearings. Factory preset cutters (.020'.040'.060'.080' oversize) mean you won't have to use a micrometer and you will get perfect results every time. The hydraulic feed is built into the chrome alloy steel bar for quick and easy setup. You also receive a thrust cutter as standard equipment.
If you have been sending out this profitable work, now is the time to order a 'Pocket Rocket 2000'. You will find it pays for itself after line boring only 25 cases. Easy to use, professional results every time, and a fast payback are solid reasons why the 'Pocket Rocket 2000' is a money maker for any shop rebuilding VW engines.
(A 3/8' drill is the recommended power source.).
Counterbore & Sleeve Cutting ToolsApex Tool Company carries a full range of upper and mid stop counterbore tools. Our M series upper counterbore tools are designed to be low profile and allow in chassis shim cutting on most vehicles. These tools are designed to last for years of constant use and the plates will interchange with the Kent-Moore Porta Tool Machine. We also carry midstop and a ISX dedicated counterbore tool.
Why wait for a mobile machine shop to do your counterbores? These machines are easy to use and get the job done fast and to perfection.
. Location: » » » What About Line Boring Sometimes you are forced to use a line bored case, this could be from financial reasons to time. Whatever the requirement, it is your choice to be responsible for and it is critical you know that it is unlikely to provide 100% life and will never stand up to any hard use. Treat it tenderly and it will give back the most it can.
When the case is only slightly worn and you want to line bore and reuse it, the #1 question will be, 'Who is qualified to do it the correct way? Do they have the correct tools? How can I tell if they did it right if I don't have any precision tools?' Those are the $64,000.00 questions.
Most shops use a simple electric drill (some use a lathe to feed the same tool) driven tool that centers on the pulley and seal holes. This is a poor way to be assured of a precision center. The pulley end will rarely be round and straight. The tool, which is inserted in both ends of the case, is bushed to allow the bar to turn. These bushings are fairly good when brand new. As they wear they get sloppy and allow the alignment to change and have no adjustment to them. These will determine whether your line bore is maintained in the same place or moved as well as what size it is.
When it is perfectly straight to the pulley, cam tunnel, and flywheel, all is great. However, most of the time it ends up out of alignment, then the gear size is way off, pulley and/or flywheel seal leakage’s show up after a few thousand miles. The one failure seldom connected to a line bore problem is wrist pin keeper failure. Because the crank is no longer lined up, the rod runs at an angle and pushes against the pin loading the keeper beyond it’s capabilities.
All of these are undetectable with normal measuring equipment so it is really a gamble. When the case is mounted on its original (tooling) fixture pads to be line bored the chances of a proper line bore are much better, there are only a couple of these machines in the USA. Now it gets down to the capability of the machinist. How close can he dial into the original center line and how close can his machinist perform the operation?
How close can he set his tools? The message in all of this is buyer beware. Do not just listen to their story. Check out what they can do. Look over the equipment. What I do is have them tell me what they use for equipment and how they measure it for alignment to the cam, pulley, flywheel seal hole, and cylinder seating surfaces.
If the answers do not support what has just been covered, just say 'Thank you' and find someone else. Whatever you do, please do not use this information to make them wrong or you will get to hear their story on how they have done 250,000 cases this year and never had a failure, low oil pressure or overheating problems. There are no products to list in this category. Quick Find Use keywords to find the product you are looking for. Information Sunday, August 19, 208 requests since Thursday, December 16, 2004 by Canvas Dreams LLC and by Pearl Compass. Please about errors or questions. We value your input!
Any and all references to the company Volkswagen, or the VW name are strictly for reference only. The GENE BERG name and GENE BERG products are protected under trademark, copyright and patent law, any violations will be pursued. GENE BERG ENT. Is not a part of any companies mentioned or linked to this website and any beliefs of those companies are not necessarily the beliefs of GENE BERG ENTERPRISES.Site maintained by Copyright ©2018 GENE BERG ENTERPRISES all rights reserved.
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I was surprised to see negative postings about the Porta-Tool Mainliner. I am 60 years old and have been a machinist/mechanic all my life.
I started rebuilding VW motors while I was still in high school. Over the years I've learned a lot.
In 1980 I purchased a Mainliner, I READ THE INSTRUCTIONS. I used this tool to line bore dozens of cases over the years and it has always done an excellent job for me. As a machinist who has made precision bearings for virtually all aircraft engines that fly today as well as the bearings for the Space Shuttle I am well trained on making products with tolerances sometimes down to 30 millionths of an inch. I always gauged bored cases with a dial bore gage after I bored them. I was always impressed with how accurate the bores were time after time, even when switching between cutters. The only problem I had with this tool was after years of use I needed to put some oil in the hydraulic feed unit as some evidently had leaked out. The only addition I added to the Mainliner was I made my own setting tool for the cutters so I didn't have to bother sending them out to be sharpened.
I did know of one person with a mainliner that had problems with it, but the problem was self-inflicted. When he machined a case, he only torqued down the six large case nuts and neglected to tighten the two 13 m/m nuts that straddle the small main bearing near the crankshaft pulley.
Having said that. There are people in this world who shouldn't pick up a hammer, never mind a line-boring machine. I have certainly had blocks over the years that were not rebuildable because they were heat warped or severely pounded, but if everything else was o-k, the Mainliner did an excellent job of machining the main bearing seats.
Old Fart, been there done that, in some cases may have been the first to do dat. I agree with mji1198, in the hands of a reasonably competent individual equipped with an electric drill of sufficient capacity a Porta-Tool can do wonders.
We always sharpened our cutters and sent the whole mess to a really good local machine shop for calibration every 100 uses or so (or at the first hint of there being an issue - a cutter that was starting to dull would leave a typical 'interference pattern' on the machined surface). I guess we were lucky, ours never leaked fluid.but if it did I would've gladly paid whatever it cost to fix that. True, it can only pick up the existing centers of the front & rear 'seal' openings so there are cases (pun intended) where it's inadequate, but they're few in number.
Another tool that was great to have around was the cutter which pilots in the #1 and #3 cam-bearing bores to whack #2 back out to standard on a slightly-warped case.can't remember who made that one, but it saved hours of handwork when you had to salvage a hammered case for a low-buck build. With just those two tools I was able to recycle several mismatched case halves into functional engines.including one that set a track record at the local circle track - when it went through the mandatory tech inspection there were dropped jaws over it having 8mm head studs on one side and 10mm on the other Yeppers, IMO the Mainliner is an underrated piece of equipment. The tool that you are talking about for the cam tunnel was made by cold form tools and after screwing around in the eighty's with cams bores being tight i purchased one and use it on all the cases that i line bore.
I also have 3 cold form line-bore bars a.020.040 and a.060, and a mainliner99 portatool line-boring bar that i have all the cutter for.020.040.060.080 and.100 cutters the portatool works great and i haven't had any troubles with it when used correct i bought my mainliner back in the 70s. The tool and the tech must not be to bad because Caterpillar bought portatool for the hydraulics's to use on their repair of bucket bushings repair.
I also make a setting fixture for setting the tool bits and sharping them as there is no one that i could find to do this except an older fellow in calif that's out of business now. I was/am thinking about offering this service but have now persued it lately. And didn't know if there was enough interest in doing it. I use regularly the earlier version of the portatool. The vw 700, with new and enlarged centers. I have them done on precision lathe and fitted them also with self lubricating bushes. It gives a very good service.
I have also a ML-99, rebuilt too, but i prefer the earlier one because it is more precise. The earlier ones have also chrome bars that ride better in the bushes. I bought 4 set of early tools, so i have the bars ready with cutters numbered and dedicated to the bar. I keep track of every cut and sometimes i adjust the individual cutter that gave deviation in measure. I use also and old german tool for adjusting the center cam bore. For machining thrust i prefer the truline dedicated cutter.
(assenmacher?) very fast and precise.
Having described my invention, what I claim as new and desire to secure by Letters Patent is 1. BACKGROUND OF THE INVENTION One or more of the crankshaft main bearing bores in the block of an engine frequently become worn or axially misaligned due to warpage from heat distortion or the like which requires that the engine be torn down for repair.
The crankshaft bores are individually partially formed by a semi-circular bearing saddle integrally cast and machined within the block with the saddle having a semi-circular machined bearing cap releasably fitted thereto so as to define a cylindrical bore. Presently, the factory provides fully finished precision replacement caps for those caps that have experienced some type of failure, distortion or other malformation such as having become scored or otherwise worn to the point of impairing proper engine operation. Such caps are adjusted in the field by the use of shims which is a tedious, time-consuming job. Furthermore, true concentricity of the bores cannot always be accurately re-established by this method nor precise axial alignment of any particular bore with its adjacent bearing bores even if true cylindricality of each bearing bore is obtained.
Conventional field boring bars for this purpose usually mount a single tool bit within a slot in the boring bar itself. Consequently, the boring bar must be axially repositioned during the boring operation for each main bearing bore. The tool bit has to be tediously set for each cut through the individual bearing bores with a micrometer after installation of the boring bar in its desired central position within the existing bores of the block. This operation is extremely difficult accurately and conveniently to accomplish in view of the relatively small space afforded within the block adjacent to the main bearing bores.
Furthermore, such conventional bars are required to be of a sufficiently large diameter rigidly to hold the tool bit to prevent chatter and the like so that the weight thereof is extremely difficult to be handled by a single workman. The only other line boring machine presently available accommodates the entire block which is similar to the machine employed during initial manufacture of the block which is too cumbersome and expensive for use in the field. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an improved line boring bar assembly. Another object is to provide such an assembly that is portable. Another object is to provide such an improved portable line boring bar assembly for in-line boring the main bearing bores of engines. Another object is to provide an improved portable line boring bar assembly of the character described which is relatively lightweight, simply constructed, and economically manufactured. Another object is to provide an improved portable line boring bar assembly which can be conveniently employed in the field.
Another object is to provide an improved portable line boring bar assembly which permits the use of semi-finished bearing caps which are easily and conveniently finish-bored in assembly upon the bearing saddles of an engine block. Another object is to provide an improved portable line boring bar assembly which is ideally suited for boring one or a plurality of main bearing bores in an engine block with a single set-up of the boring bar on the block, thus obviating the inaccuracies, inconveniences, lost time and expenses of repetitious re-setting operations. Another object is to provide an improved portable in-line boring bar assembly which utilizes an elongated boring bar adapted to be rotatably driven at one of its ends by a conventional electric drill and positively axially driven at its opposite end by an hydraulic feeding device mountable on the block. Another object is to provide an improved portable in-line boring bar assembly in which said drive devices are selectively connectable at either end of the boring bar. Other objects and advantages of the present invention will subsequently become more clearly apparent upon refernece to the following description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of the lower side or pan rail of an engine block having a portable in-line boring bar assembly embodying the principles of the present invention installed therethrough and illustrated as adapted for boring at least two of the main crankshaft bearing bores of the engine. 2 is a vertical longitudinal section taken substantially centrally through the block of FIG. 1, showing the in-line boring bar assembly of the present invention in side elevation. 3 is a somewhat enlarged end elevation of the engine block, as viewed in the direction of the arrows on line 3-3 of FIG. 4 is a somewhat enlarged transverse vertical section through the block and in-line boring assembly, taken on line 4-4 of FIG.
Vw Tools Special Tools
5 is a top plan view of a bridging member of one of the upright bearing supports for the in-line boring assembly removed from the engine block. 6 is a somewhat enlarged front elevation of one of the cutter bit holders of FIGS. 1 and 2 shown in clamping relation about the boring bar of the present invention. 7 is a somewhat enlarged transverse vertical section through the boring bar, taken on line 7-7 of FIG. 1, showing the cutter bit holder in side elevation. 8 is a somewhat enlarged rear elevation of the cutter bit holder of FIGS.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly to the drawings, a portable in-line boring bar assembly embodying the principles of the present invention is generally indicated by the reference numeral 10 and is shown in an operating position extending through an engine block 11. The engine block is of conventional construction and is shown in an inverted position to present its lower surface or pan rail 12 during the line boring operation.
The block has a plurality of semi-circular integrally cast bearing saddles 14 disposed therein in predetermined longitudinally spaced relation. A corresponding number of semi-circular bearing caps 16 having diametrically oppositely extended pads 17 are conventionally bolted by cap screws 18 to the saddles 14 to form a plurality of main bearing bores 19 in the block. After removal of the bearing caps 16 and the engine crankshaft, not shown, only one or two of the bearing bores may need attention in instances where the associated bearing cap has been damaged by fatigue failure or the like or through heat distortion the block and saddle 14 have shifted out of alignment with the adjacent main bearing bores. On the other hand, such warpage of the block or damage to the bearing caps may be so severe that all the bores require reworking. In either instance, the present invention is ideally suited for the task. The repair of the main bearing bores 19 of the block 11 is easily and conveniently accomplished by the boring bar assembly 10 of the present invention which provides an elongated cylindrical boring bar 20 of a length to extend entirely longitudinally through the block. The boring bar includes opposite ends 22, each of which has a drive adapter socket 23 therein with a locking setscrew 24 extended radially through the end of the boring bar for extension into its associated socket.
A pair of annular centering rings 30 are employed initially to locate the boring bar in a precisely coaxial centered relation with respect to the bearing bores in the engine block 11. Each of the centering rings has a circular aperture 32 through which the boring bar is axially slidably received and an outer periphery 34 of a size adapted to be received within the bearing bores of the block in tightly wedging relation. The boring bar assembly 10 of the present invention also includes a plurality of upright bearing assemblies 40 which are particularly useful for supporting the boring bar intermediate its ends when rebuilding relatively long engine blocks such as diesel tractor engines and the like. However, the embodiments of the present invention are also readily adapted to be provided in various sizes including a relatively small boring bar assembly for the relatively small engines utilized in Volkswagen automobiles and the like.
As best shown in FIGS. 4 and 5, each of the bearing assemblies 40 has an elongated mounting post or arm 42 having a predetermined lower bifurcated end 43 and an opposite upper end 44.
The upper end includes a pair of diametrically opposed outwardly extended pins 46. An annular bearing 50 is pivotally mounted on the lower bifurcated end 43 of the mounting post to permit relative movement between the bearing and the mounting post during initial assembly of the boring bar 20 into the block 11. The bearing has an upwardly extended tab 52 which is slidably received between the legs of the bifurcated lower end of the post and which is pivotally held in assembly therewith by a capscrew 53 screw-threadably extended through the legs and tab. The bearing further includes a pair of clamping pads 54 in lateral extension from the bearing which have a locking setscrew 55 extended therethrough to adjust the tension of the bearing around the boring bar. The bearing mounting posts 42 are individually supported on the engine block 11 by an elongated bridging member or bracket 60 having opposite ends 62 and an intermedite enlarged boss 63 disposed centrally thereof. The opposite ends of the bridging member include elongated bolting slots 65 through which are extended mounting capscrews 66 which are screw-threadably received in selected pairs of a plurality of screw-threaded holes in the pan rail 12 of the engine block. A transverse bore 67 is formed through the central boss 62 of the bridging member and a pair of diametrically opposed clamping slots 68 extend through the boss in communication with the bore.
Vw Align Bore Tool
A locking setscrew 70 is screw-threadably extended through one of the slots in order tightly to clamp the bridging member about the mounting post 42 of the bearing assembly extended therethrough. As best shown in FIG. 1, it will be noted that the pins 46 in the mounting post 42 are angularly related to the plane of the slots 68 through the bridging member in order to provide a stop in the event that the boring bar is inadvertently removed from the bearing to preclude complete separation by downward gravitational descent of the mounting post through the bridging member. The boring bar assembly 10 of the present invention further includes a plurality of cutter bit tool holers 75 which are adapted to be individually clamped about the boring bar 20 in any desired location between its opposite ends 22. As best shown in FIGS. 6 through 8, the tool holder provides a semi-circular tool mounting portion 76 and an opposite clamping portion 77. Pairs of outwardly extended assembly flanges 78 and 79, respectively, are releasably constrained in assembly by a pair of screw-threaded locking setscrews 80 extended therethrough for tightly clamping the tool holder about the boring bar 20.
The tool mounting portion 76 of the holder provides a radially outwardly extended protuberance 82 which has an elongated tool bit mounting slot 84 extended therethrough and a tool bit clamping screw 85 laterally extended through the protuberance in communication with the slot. A conventional carbide-tipped tool bit 87 is adapted to be mounted within the slot 84 of the protuberance and tightly clamped by the locking screw in any desired extended position therefrom corresponding to the size of the main bearing bore to be finished or initial cut to be made. The boring bar 20 is adapted to be rotatably driven by a conventional electric drill 90 having a drive chuck 92. A universal coupling adapter 94 is employed by the boring bar assembly 10 of the present invention for connecting the electric drill to either end 22 of the boring bar. The adapter has an end 95 which is slidably receivable within the socket 23 in the selected end of the boring bar which is constrained therein by the setscrew 24. The adapter includes an opposite end 96 which is tightly received and clamped within the chuck 92 of the drill. The boring bar 20 is adapted to be axially indexed or traveled through the block 11 by an hydraulic feeding device generally indicated by the reference numeral 100.
Such feeding devie is substantially similar to that employed with the boring tool of my prior U.S. 3,331,266 to which attention is directed for a full description of its internal mechanism and operation. Briefly, however, in its present use, the hydraulic feeding device provides an elongated cylindrical body 102 having an elongated piston actuating control rod and handle assembly 103 extended from the outer end thereof and an opposite coupling member 104 extended from its opposite inner end for extension into the socket 23 at the opposite end of the boring bar from the drill 90. The hydraulic feeding device is adapted to be rigidly mounted on one end of the engine block 11 by an anti-rotation torsion bar mounting frame 106 adjustably secured to the end of the block.
The mounting frame 106 provides an elongated torsion bar 107 having an elongated adjusting slot 108 therein which is bolted to the end of the block 11 by a capscrew 109. The bar provides an elongated rod 110 which is extended therefrom in spaced substantially parallel relation to the cylinder body 102 of the hydraulic feeding device.
The feeding device has an arm radially extended therefrom providing a sleeve 112 circumscribing the rod. A thumbscrew 114 is screw-threadably received in the sleeve for tightly clamping the feeding device on the rod 110. The hydraulic feeding device is adapted axially to drive the boring bar in either direction by extension or retraction of the connector 104 relative to the body 102 upon appropriate manipulation of the actuating handle 103 depending upon the direction of rotation of the boring bar and location of the tool bit holders 75 relative to the main bearing bores 19 of the engine block 11. OPERATION The operation of the described embodiment of the subject invention is believed to be clearly apparent and is briefly summarized at this point. Prior to extension of the boring bar 20 through the main bearing bores of the engine block 11, a pair of the centering rings 30 are rested within the selected bearing saddles 14 and the bearing caps 16 installed by manipulation of the capscrews 18 through the mounting pads 17.
The salvagable bearing caps are replaced on the bearing bores not requiring attention while new semi-finished bearing caps are utilized on those bores requiring the reworking operation. As shown in FIG. 2, the centering rings are disposed in the end main bearing bores which, in this particular instance, do not require re-boring.
When, however, the end bearings are required to be re-bored, the centering rings can be disposed in any of the selected inboard main boring bores in sufficiently spaced relation to afford the necessary stability to insure precise centering of the boring bar through the bores in the engine block. After installation of the centering rings 30 and proper tightening of the bearing cap mounting screws 18, the boring bar 20 is oiled, extended through one of the centering rings and axially shoved into the block for extension through one of the upright bearing assemblies 40 which may be held in any selected position between a pair of the main bearing bores. The boring bar is also extended through a second upright bearing assembly adjacent to the opposite end of the block and through the centering ring 30 to a position where the opposite ends 22 of the boring bar are outwardly extended from their adjacent ends of the block. The bridging members 60 are installed over the mounting posts 42 of their respective upright bearing assemblies 40 by sliding the bore 67 in the boss 63 over the upper end 44 of the mounting post with the pins 46 sliding through the slots 68 in the bridging member to permit downward sliding movement of the bridging member until rested upon the upwardly disposed pan rail 12 of the engine block. The bridging member is rotated slightly about the mounting post in order to dispose it in a plane substantially normal to the axis of the boring bar so as angularly to misalign the slots 68 with the pins 46.
Accordingly, in the event that the boring bar is inadvertently removed from the block, the upright bearing assemblies 40 will be supported by engagement of the pins with the top surface of the bridging member. The lock bolts 70 are then tightened into selected threaded holes in the pan rail of the block and the bearing 50 locked by tightening of the lockscrew 53 so as precisely to hold the boring bar in centered relation with respect to all of the main bearing bores in the block as established by the centering rings 30. At this point, the centering rings may remain in their initially installed positions or removed from the block, as desired. Such removal may be necessary in instances where the main bearing bore in which they were disposed is required to be reworked. In any event, the tool bit holders 75 are mounted in circumscribing relation about the boring bar 20 in any desired location closely adjacent to each of the main bearing bores to be reworked.
The electric drill 90 is installed at one end of the boring bar and the hydraulic feeding device 100 disposed at the opposite end of the boring bar in the manner previously described. Upon energization of the hydraulic feeding device and the electric drill, the tool bit 87 is rotated in cutting relation into and through its adjacent main bearing bore to finish the same to the desired size. While only one or two of the main bearing bores usually require re-boring, it is apparent that a sufficient number of the tool bit holders 75 can be simultaneously mounted on the boring bar for concurrent boring of all the main bearing bores in a single pass. As shown in FIG. 2, the boring bar tool bit holders 75 are axially fed from right to left upon retraction of the connector 104 into the cylindrical body 102 of the hydraulic feeding device 100. However, if there should be insufficient clearance to the left of the main bearing bores to permit the bore to be fully finished by the tool bit 87, the holders can be initially mounted on the left side of the bearing bores and the actuating handle 103 of the hydraulic feeding device appropriately manipulated to cause extension of the connector 104 from the cylinder body thereof for feeding the boring bar from left to right, as viewed in FIG. In view of the foregoing, it is readily apparent that the structure of the present invention provides an improved portable in-line boring bar assembly which enables the main bearing bores of an engine block easily and conveniently to be re-bored in precise axial alignment and individually returned to precise cylindrically and concentricity.
The boring bar assembly of the present invention utilizes a conventional electric drill as a rotary drive member and a known hydraulic axial feeding device which is borne by the engine block so that such in-line boring operation can be successfully accurately accomplished in the field. Such assembly enables the use of semi-finished bearing caps which are accurately finished after installation into the engine block so as to provide a custom assembly with their associated main bearing saddles to re-establish the same optimum tolerances as initially provided by the factory. Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the illustrative details disclosed.
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