Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
This document shows how to build a stand for the Harbor Freight portable bandsaw shown at left. The stand converts the saw into a benchtop cutoff saw, as well as a benchtop vertical bandsaw. In order to use the bandsaw for metal cutting, the bandsaw blade supplied with the saw is replaced with a 24 tpi metal cutting blade.
Harbor Freight item #47840 portable bandsaw.
Additional photos and details can be found at this link: https://sites.google.com/site/lagadoacademy/machining---lathes-mills-etc/tools---portable-bandsaw-stand
Horizontal cut-off mode
Vertical cutting mode
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 1 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
BRACKET
2"
Angles: (see note 1) A = 127° B = 90° C = 123°
C
7.6 2
6.2"
"
Bracket
Position of blade.
2"
A
B 5"
3”
Material is cold rolled steel plate, 3” width and 1/8” thick. Drill holes after bending (see notes 1 and 2).
2"
5"
6.2"
2"
Exaggerated vertical scale. Actual thickness is 1/8” (0.125”); mill groove to depth of 0.025”.
15.2”
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 2 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
CLAMPS
.625” (5/8”)
Drill and tap for 1/4”-20
.625” (5/8”)
Cut 1-1/4” angle iron to make clamps.
1.25“
Cut here
1”
0.09"
BANDSAW FRAME
BRACKET
This detail shows how the clamp is used to clamp the bracket to the bandsaw frame. Note that the hole in the clamp is threaded to fit the socket head screw (see note 3).
1/4”-20 x 1/2” socket head screw
CLAMP
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 3 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Clamp and Hinge Placement The photo below shows how the bracket is fastened to the bandsaw and hinge (note: the washers under the hinge were an early attempt to adjust the blade angle, and were not used in the final assembly). The screws from the original blade cover are used to screw the bracket to the frame, and two clamps are also used on either side. Holes are drilled in the bracket (not the bandsaw frame) for the frame screws, clamp screws, and hinge bolts.
screw
clamps (2)
Bolts, washers, lock nuts
screw
Lag screws
clamps (2)
washers under the hinge were an early attempt to adjust the blade angle, and were not used in the final assembly
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 4 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
BASE
See note 3
24”
3”
5-1/4”
TOP VIEW
11-3/4”
See note 4
Hinge block
Rubber stop See note 6 Vise Block See note 5
Base is made of 3/4” plywood. Vise block and hinge block are made from multiple pieces of plywood glued up to required thickness. Hinge block is 2-7/8” H x 5-1/2” L x 2-3/4” W. (see Note 4) Vise block is 4” H x 8.5” L x 3.5” W. (See Note 5)
SIDE VIEW Vise Block
“foot” See note 7
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 5 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Hinge, Hinge Block, and Vise Block
Hinge is fastened to the hinge block with lag screws, and to the bracket with bolts, washers, and lock nuts.
Hinge block showing “steps” cut for hinge clearance, and corner cut for bandsaw clearance.
The original hinge pin was replaced with a fitted pin (see Note 4).
The vise block is made to fit the vise I had on hand. A hardwood block in front of the vise provides a level surface extending to the blade. The small wood block screwed to the front acts as a stop for the bandsaw as it cuts through the workpiece.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 6 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Blade Cover
Cutting the side piece (large section to the right is waste).
Gluing on the cover.
Cover trimmed and fitted to the bandsaw.
The blade cover is an important safety requirement, especially because when using the bandsaw for horizontal cutting there is a natural tendency to place the left hand on the frame, which would also place it immediately over the blade if there were no cover. Since I didn't want to make any permanent modifications to the bandsaw, I made a new blade cover out of plywood instead of cutting down the provided cover. I glued up scraps of plywood to 1" thickness and cut out a side piece on the bandsaw; the bandsaw itself was used as a template to lay out the curve. The side piece was glued to a cover made from 1/4" plywood , which was then trimmed down on the bandsaw as shown in the photo below right. The cover was fastened to the bandsaw using the existing screw holes for the provided blade guard, but using longer screws to compensate for the thickness of the plywood. "benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 7 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Electrical
To improve control of the saw, I added a switched outlet at the front (see photo above left). The cord from the saw is looped under the stand, coiled on a simple wooden cleat (see photo above right), and then plugged into the front. The switch on the handle of the saw has a lock down button, so the bandsaw switch can be locked in the on position, and then switched on and off with the switched outlet.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 8 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Adjustments
Adjusting the cutting blade square to the vise is easily done by making slight adjustments to the vise and hinge before fully tightening the lag bolts that hold them down. To verify that the blade is making a proper vertical cut, make a test cut in a good sized piece of metal. When I did this, the cut was seen to angle outward from the vise. On close inspection, it could be seen that the blade was actually tilting very slightly off vertical, such that the bottom of the blade was tilted outward from the vise by a barely noticeable amount. To correct this, I removed both sets of blade guide rollers and inserted a washer between the roller bracket and the saw frame as a shim to give the roller bracket a tiny bit of compensation tilt. Blade guide rollers (there are two sets of these).
Depending upon how your test cut looks, you may need to shim one side or the other of the roller guide assembly to compensate.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 9 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Vertical Cutting Mode To cut in the vertical position, the bandsaw is simply raised to the full upright position. In this position, the bandsaw frame rests on a hard rubber block. I had initially planned to add some sort of locking mechanism to lock the saw in the upright position, but in testing this does not seem to be necessary as the saw is quite stable in this position, and while cutting the tendency is to push the saw more firmly into the upright position. One disadvantage of the design of this stand is that when cutting in vertical mode, you have a to reach quite a bit to get to the blade; this also makes it more difficult to see how the cut is proceeding. This can be alleviated somewhat by standing to the side while cutting. In the few times I have used the bandsaw in the vertical position, this has been more of a minor annoyance than anything else, so it may not be an issue worth addressing. Cutting table: A cutoff table was constructed from sheet steel, together with some mounting adapters made from stainless steel (any type of steel or other hard metal would likely work for the mounting adapters – I just happened to have some stainless steel of the right dimensions on hand). Note that while I have given precise dimensions (for the most part) on the following pages, the actual required dimensions are somewhat arbitrary (except where the adapters need to be fitted to the bandsaw frame). It should also be noted that bandsaw dimensions may vary from model to model, so the dimensions given should be used as a guide, and should be verified with your particular bandsaw.
I should note that fitting the cutting table to the bandsaw was very much a trial and error process. Cutting the blade slot in the table top allows the sheet to be used for test fitting. Using this method, I fitted the clip (located to the left of the blade, on the under-side of the table) by locating the clip and table in the desired final locations and sticking the two together with double-sided tape; I could then use a transfer punch to mark the hole locations in the plate. With the plate drilled and countersunk, and the clip screwed in place, I could then mark the required location of the other mounting adapter by a similar test fitting process.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 10 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
.562” (9/16”)
Cutting Table Mounting Adapter - Vertical Cutting Mode 1.245” .602”
The positions of the 7/32” holes for mounting the adapter to the frame of the bandsaw are determined by the positions of the existing screw holes in the bandsaw for the blade stop. The 10-32 screw holes for mounting the cutting table top are somewhat arbitrary, and are determined by test fitting the table before drilling. Screws used are 10-32 x 1/2” flathead screws.
1.758
.310”
Drill and tap for 10-32
The mounting fitting is attached to the bandsaw by two "screws" made from drill rod - one end of the rod is threaded to fit the blade stop mounting holes (M5 x .8), the other end is 10-24 with a washer and lock nut. The length of the drill rod is determined by the width of the adapter, which is somewhat arbitrary.
.928”
7/32” diam.
2.989
Thread 10-24 Thread M5 x .8
The picture to the left shows the mounting adapter in place for test fitting, before table mounting holes have been drilled.
Above is the “screw” that fastens the adapter to the bandsaw. Length is as required to fit the adapter.
The picture to the right shows the mounting adapter with the “screws” that fasten it to the bandsaw.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 11 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Cutting Table Mounting Clip - Vertical Cutting Mode The photo to the left shows the completed clip; note that the positions of the screw holes for mounting are somewhat arbitrary. The photo to the right shows the clip mounted to the under-side of the table. The exact position of the clip is determined by test mounting the table before drilling and countersinking holes in the table.
Starting dimensions are 562” x .562 x 1.748” Chamfer here
Drill and tap for 10-32
Below is shown how the clip mounts to the under-side of the cutting table. Screws used are 10-32 x 1/2” flathead screws. Note that the countersinking for the screw head extends into the clip (i.e., screw hole must also be countersunk); this is also the case for the other mounting adapter. 10-32 x 1/2” flat head socket screws used in all cases.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 12 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
Cutting Table - Vertical Cutting Mode 10"
Mounting adapter
7.5"
“Clip”
3.5"
5"
The top of the cutting table is a steel sheet 10" x 7.5" x .110" which I had picked up at a garage sale. Building on this, I built a mounting system to attach the sheet to the bandsaw. a slot for the bandsaw blade was cut in the steel plate, using a 3/32" end mill. This could probably have been done by just using the bandsaw to cut a slot, but I felt that the mill would do a neater job. The result is a good size metal cutting table which can be mounted to the bandsaw with only two screws. - this makes adding or removing the table simple and quick (note that although there are four screws shown in the picture, only two screws need to be removed to un-mount the table). The exact location of the screw holes is determined by test fitting the table and marking the required locations, which are then drilled and countersunk. The positions of the “clip” and the mounting adapter are shown in dashed lines.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 13 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
My design goals for this stand were as follows: ● ●
●
No welding required (I don't have welding equipment up to the job) No drilling, cutting, or irreversible altering of the bandsaw (if the saw broke during the warranty period, I wanted to be able to return it) Use materials already on hand as much as possible
To accomplish the above goals, I used plywood for many parts of the stand. The plywood is coated with wipe-on polyurethane to protect from oils and such. Further, I intentionally "overbuilt" the plywood sections to make sure the stand would be solid, sturdy, and would hold up to usage. Also, one of the first things I did was purchase metal cutting bandsaw blades, so I could use the bandsaw to help build the stand. I was able to find a package of three 24 tpi blades at a local big box store for about $24; these are not bimetal blades, but seem to work OK anyway. I used one of these blades to do all of the metal cutting for this project, as well as numerous test cuts of various pieces of steel and aluminum, and I am still on the first blade. If I ever manage to break all three blades, then I'll consider buying something more expensive. I should also note that the vise I used for this project was a small drill press vise I happened to have on hand. You will of course have to make adjustments to these plans to accommodate the vise you will be using. My suggestion if to purchase a cheap drill press vise if you do not already have one available; an appropriate vise can likely be purchased for $20 - $25 if necessary.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 14 of 15
Bandsaw – Benchtop Cutoff Modification Oct 26, 2013 By Kaje at https://sites.google.com/site/lagadoacademy/home
NOTES 1. The bracket is bent by heating with a MAPP gas torch along the scored line (I did this with a 90° end mill on a mini-mill, but this could also be done with a hacksaw), and then bending with one end clamped in a vise. Do the middle bend first, then the two end bends. The holes are drilled after bending, so that the metal does not bend where the holes are. The angles should be considered somewhat approximate. Also, note that the sides of the bladesaw skirt are angled slightly inward, so this must be accounted for. 2. The positions of the holes in the bracket are determined by test fitting the bracket to the frame and drilling the holes to match. One hole in each end of the bracket is drilled to match the existing screw holes in the frame where the blade cover was attached. An addition two holes are drilled for the clamps; the clamps must be test fitted as the frame has internal webbing. Locate the clamps to avoid the webbing, and drill holes accordingly. I had some concern that the clamp material would not be thick enough to provide a good depth of thread, but it seems to work. 3. BASE: The base is made from 3/4” plywood. The exact size is not critical, and is determined in part by the size of the vise that will be used. 4. The hinge block is made from glued-up solid wood pieces. It is basically a 2-3/4” W X 2-7/8”H X 5-1/2” L block. “Ledges” were cut in the front of the block to provide room for the hinge and its fastening bolts, and one corner was cut away to allow room for the bandsaw skirt. For the hinge I used a door hinge from my junk box; however, this hinge has a very small amount of wobble, which is “amplified” by the effective lever of the bandsaw, so that the blade moved by about 1/8”. To address this I removed the hinge pin, drilled and reamed the hinge to 0.250”, and replaced the hinge pin with 0.250” drill rod, threaded at both ends; the drill rod hinge pin was fastened in place with lock nuts and washers. 5. The vise block was made from glued up pieces of plywood. The dimensions shown are for the vise I used, and must be adjusted for a different vise. One corner of the block is sawed out to make room for the bandsaw skirt. A hardwood block is attached to top (blade side) to provide a level support form the vise to the blade. A small wood block screwed to the side of the block acts as a stop for bandsaw. 6. A “stop” is provided to keep the bandsaw at 90° when raised to the vertical position. I just happened to have suitable piece of hard rubber in my junk box, but a pine block would probably do just as well. 7. A strip of hardwood (approx. 3/4” thick) was run down each side of the base. This provides room for cord storage underneath, and also makes it easier to get hands under the base for lifting.
"benchtop-cutoff-by-kaje" © 2013 by Kaje at https://sites.google.com/site/lagadoacademy/home. This work is made available under the terms of the Creative Commons Attribution-ShareAlike 3.0 license, http://creativecommons.org/licenses/by-sa/3.0/.
Page 15 of 15
